The wacky world of bladder stones – Episode 2

The wacky world of bladder stones – Episode 2


April 3, 2014


From the Desk of Dr. Voorheis


When last we spoke, we had reviewed the pesky business of bladder stones including types of stones as well as the process of diagnosis and a brief overview of treatment options. Here in Episode 2, I will address treatment options for specific stones in greater detail as well as share the story of Feline Lower Urinary Tract Disease or FLUTD.  Yes, my cat clients finally have a blog to call their own!  

On a personal note, I hope you are all well and that the recent earth moving events caused no problems for you. I know that a few of our clients had damage to their homes. I wish you all the best as we all may be a little hypersensitive to rattles and vibrations. I was typing in the dark this morning at the kitchen table when one of my cats jumped on the table to help (of course). This caused the table to vibrate and I jumped about 3 feet. No kidding. Anyway, back to these pesky stones.

There are two basic principles of treatment for bladder stones. The first is the relief of any urethral obstruction. We do this through passing a small catheter around the stones, tapping into the bladder to relieve pressure on the bladder, or dislodge the urethral stone by moving it back into the bladder. This process is called retrograde hydropulsion. Rarely, an emergency urethrotomy is necessary. A urethrotomy is a surgical procedure where an incision is made into the urethra to relieve the urinary obstruction. Decompression of the bladder may also be necessary.  The second option for dogs who are obstructed is that they may require emergency relief of their obstruction. Those dogs need IV fluids, electrolyte monitoring and correction. Sometimes electrolytes can be so disturbed that it causes heart problems. Heart problems because of an obstructed bladder?  Yes!   More commonly, an obstructed urinary tract shuts down kidney function resulting in signs consistent with acute renal failure. In this instance, treatment is initially directed at life saving measures prior to stone removal or dissolution attempts. 

 After the initial clearance of urethral obstruction, we arrive at a place where more decisions need to be made. The reality faced by most veterinarians who see dogs and cats with bladder stones is that in most instances we don’t know what the chemical composition of the stone is. In order to treat the animal in a non surgical way, we need to have that information. Sometimes if the stones are small enough we can use a procedure called “Urohydropropulsion” to push some of the stones out of the urinary tract. More often than not the stones are too big to be pushed out of the bladder. There are some cases and some types of stones where the stones are of various size and we can get enough for a diagnosis prior to surgery.  In those instances we may be able to avoid surgery if the stone is amenable to dissolution. I am often asked if it is cheaper to avoid surgery by medical dissolution. The answer is no. Dogs undergoing medical dissolution will require multiple trips to the veterinarian for urinalysis, radiographs to monitor progress, and bacterial cultures. That being said, remember that every case is unique and a treatment plan will be specific for the individual animal. At WBAH, we do not practice cookie cutter medicine.

 When we do not know the chemical composition of the stone, the animal will require a surgical procedure called a cystotomy. In MANY cases, even if we do know the chemical composition of the stone, surgical removal is still the best choice for relieving the problem. Once we know what stone type we are dealing with, our job is to try and prevent stone formation. In general, whether we have managed the stone by medical dissolution or surgical removal, prevention is directed to the induction of diuresis (dilute urine) and the eradication of urinary tract infections. Giving dogs an opportunity to void frequently and performing frequent urinalysis to monitor for urine pH, crystals and bacteria should be done. Preventing stones is certainly an ongoing effort.  

 So what kind of non surgical options do we have based on knowing what type of stone we are dealing with? Well, let’s break that down.

Struvite uroliths (stones)

These are stones made up of magnesium-ammonium-phosphate and often referred to as triple phosphate stones. These stones are often associated with bladder infection.  By performing a urinalysis and culture, we can get hints that it may be a struvite stone. If the animal has a UTI (urinary tract infection) confirmed by a culture and the owner wants to try medical dissolution, struvite stones may be dissolved by feeding a struvite dissolution diet I recommend Hill’s Canine Prescription Diet S/D or Royal Canin canine URINARY SO.  On average, it takes two to three months to dissolve struvite stones using this method but the range can be as little as two weeks to as much as 7 months. The animal’s UTI must be controlled during this time or the dissolution won’t work, or certainly won’t work as well. In addition, dogs with medical conditions such as congestive heart failure, hypertension and certain kinds of kidney disease can’t be feed the stone dissolution diets. Many Miniature Schnauzers can’t be fed the stone dissolution diet because the diet has a relatively high fat content and they are prone to developing pancreatitis which can be caused by eating diets high in fats. The key to dissolving struvite uroliths is preventing or treating infection and feeding the dissolution diet EXCLUSIVELY.

 Calcium Oxalate Uroliths (stones)

There is no diet to dissolve oxalate stones. So their treatment is always surgical removal. A diet of restricted protein, moderate restriction of calcium, sodium and oxalate with a normal intake of phosphorus, magnesium and vitamins C and D, is recommended to prevent recurrence of calcium oxalate stones. The prescription diet we most often recommend is Hill’s Prescription diet u/d. The issue with this diet is that some dogs don’t like it. I’ve recently been working with certain recipes for home cooked diets to provide an alternate option. In addition, potassium citrate given orally helps prevent recurrence of oxalate stones. Citrate complexes with calcium and forms a relatively soluble calcium citrate and in the right dose causes mild alkalinization of the urine pH. BUT, if we make the urine pH to alkaline we end up forming a different kind of stone. So this stuff takes monitoring of the urine, i.e. frequent urinalysis. Lastly, I add thiazide diuretics to decrease urinary excretion of calcium and to help form dilute urine. Both are key in preventing stone formation. 

Urate Uroliths (stones)

Urate stones are relatively rare. They are seen most often in Dalmatians, English Bulldogs and in dogs with certain types of significant liver diseases. Dalmatians and some English Bulldogs have a defect in the liver transport of uric acid. Uric acid is a product of purine metabolism. Uric acid is not converted to allantoin which is soluble in urine. Uric acid is not soluble in urine. The stones that form are ammonium acid urate stones. These stones also develop with increased frequency with urinary tract infections because many UTIs increase urine ammonia concentrations. The goals in trying to dissolve urate stones are feeding a low protein diet, giving a medication called allopurinol which decreases the formation of uric acid, controlling UTIs and sometimes giving potassium citrate to balance urine pH. A low protein diet is a key. The recommended diet is Hill’s U/D. Too high of a protein diet in dogs who take the medication allopurinol can result in a stone called a xanthine stone.  These dogs are complex and require continual management. The dogs who develop these stones that are caused by their hepatic insufficiency have even more trouble. We must try to correct the underlying liver disorder if possible. If we can improve hepatic function, the stones may spontaneously dissolve. 

 Silicate Uroliths (stones)

There are no known ways to dissolve silicate uroliths. After surgical removal, diets to increase urine volume and alkalinization are recommended. So prevention is similar to that recommended for calcium oxalate uroliths (Hill’s canine U/D, potassium citrate, thiazide diuretics).  Oh, and don’t let them eat soil. In some parts of the country, silicate can be found in soil, so it’s best not to take a chance with these dogs. 

 Cystine Uroliths (stones)

As with many of the above stones, dissolving or preventing cystine stones includes a protein reducing diet, alkalinization of the urine and administration of thiol-containing drugs. Again, Hill’s U/D is the appropriate diet. Keeping the urine alkaline using Potassium Citrate is indicated too. There are two possible medications to use to try to prevent cystine stone formation.  Both complex with cystine and the resulting product makes cystine much more soluble in the urine. Of the two, d-penicillimine and N-2mercaptopripionyl-glycine a.k.a MPG, MPG has fewer side effects. 

 The key to prevention of recurrent stones is monitoring the urine. Monthly urinalysis to check for UTI, stone formation and urine pH is key. If the urinalysis suggests UTI, a culture should be performed. After stones have been removed, the next goal is to prevent them from coming back. Too often, we take a sigh of relief, and think we are done. But continuing to monitor is crucial in the prevention of new stones.  

“Ok, wait a minute doc. Didn’t you promise us something about cats and urinary tract something or another? Well, yes I did! So now let’s talk about Feline Lower Urinary Tract Disease or as we call it…FLUTD. After all, bladder stones and urinary tract infections et all…’s all living in the southern region of the animal. Partners in crime if you will. 

 So what is this FLUTD thing anyway? The signs of feline lower urinary tract disease are frequent urination, blood in the urine, difficulty or straining to urinate, inappropriate urination and partial or complete obstruction. It is equally common in females and males and overweight animals are at higher risk. These are typically young to middle aged cats and it is seen more often in winter and springtime, although it can be seen at anytime of the year. It is also seen more often following rainstorms, even in indoor cats. Go figure that one! The worst thing about FLUTD is that it can be fatal. I will explain this more in a moment, but please know that cats can die from their lower urinary tract disease. It’s no joke. 

 strained cat                

 There are a number of ways to try to get a handle of FLUTD. It can be divided into two broad categories based on the presence or absence of an identifiable cause of the lower urinary tract signs. As clinicians, we examine an animal and quickly identify the FLUTD as either obstructive or non-obstructive.Obstructive is always a life threatening emergency which requires immediate treatment.  Identifiable causes of FLUTD include urinary tract infections, anatomic abnormalities (defects in the bladder wall or urethral strictures), trauma, irritant cystitis, neurologic disorders, behavioral disorders and neoplasia and uroliths (stones! Partners in crime as I said!) can all mimic FLUTD.  However, in many cases despite a thorough check, the cause for the FLUTD is classified as idiopathic (unknown).

 FLUTD may occur in association with uroliths (stones), with microcalculi (crystals) and or mucous plugs, which also contain crystals. Just as with dogs, struvite (triple phosphate) and calcium oxalate are the most common feline stones. Different from dogs, most struvite stones in the cat are NOT associated with a bladder infection as the urine is sterile. As with dogs, there must be a high concentration of urolith forming constituents in the urine, there must be a favorable pH and there must be time for the crystals to form. 

 Urethral obstruction is more common in the male cat which is due to the length and the narrow diameter of the male urethra. Many obstructions are a combination of mucus plugs that also contain crystals. In addition, there is local inflammation that develops in response to the urethral crystals and plugs and that makes things worse as the diameter of the urethra becomes even more narrowed when it is inflamed. Even catheterization which is designed to relieve an obstructed urethra can contribute to urethral inflammation and edema. 

 A second common urolith in cats is calcium oxalate. These stones/crystals are becoming more common in cats, in part due to urine acidifying diets that are prevalent and designed to prevent struvite related FLUTD which is a true conundrum. Primary bacterial infections causing signs of FLUTD are rare in young cats (as compared with dogs). 


Urinary tract infections do occur in cats, they are more common in older cats, and more often seen in cats whose host defense mechanisms have been altered. Huh? Host defense mechanisms are those things that keep us protected. Complete voiding of the bladder is a host defense mechanism. So that means the things that prevent complete voiding of the bladder can contribute to UTI. Things like partial obstructions, anatomic abnormalities, detrusor (a muscle in the bladder) atony (weakness) all interfere with complete emptying of the bladder. Thus they can contribute to a UTI. Catheterization, especially the placement of an indwelling urinary catheter, can contribute to UTI. Chronic inflammation associated with FLUTD can also contribute to the development of UTI in cats.  

 Now here is an interesting bit of information. There are similarities between cats with idiopathic FLUTD and women with interstitial cystitis. These similarities include chronic irritative voiding patterns, sterile urine, a prominent bladder mucosal vascularity, decreased mucosal production of glycosaminoglycan and increased numbers of mast cells and sensory afferent neurons. The cause of interstitial cystitis in women is also unknown. 

Contributing causes and risk factors

  • Decreased urine volume and decreased frequency of urination. 

What are some of the things that contribute to decreased urinary volume and frequency? Dirty cat boxes.Poorly available litter box. Decreased physical activity as a result of cold weather. Obesity. Illness or confinement. Decreased water consumption due to water taste, availability or temperature. 

Ÿ • Stress 

Increased plasma concentrations of norepinephrine have been documented with cats with idiopathic FLUTD. This leads to increased nociceptive nerve fiber activity and activates neurogenic bladder inflammatory responses. Furthermore, decreased cortisol concentrations have been observed in these cats too. Although the role of stress is difficult to prove, it is often implicated. The history often indicates recent stress, boarding, cat shows, a new pet or new baby in the home or rainy weather. An inordinate amount of FLUTD shows up following rainy weather. 

Signs and Symptoms

Signs depend on the component of disease present, meaning unobstructed vs. obstructed. Unobstructed cats have frequent urination, straining and difficulty urinating, and blood in the urine. These cats will often lick their genitalia and vocalize during voiding. They will also urinate in inappropriate places. For whatever reason, urinating in sinks and bathtubs is common. Cats with either partial or complete obstruction will strain and strain in the cat box and vocalize during voiding. They will hide. Their abdomens are painful. Some will throw themselves on the floor they are so uncomfortable. Sometimes their penis will be extended from prepuce. 

 I feel like this next bit should be prefaced by a warning. What I’m about to describe is not pleasant. The above description fits an obstructed cat early in his obstruction. This is what an obstructed cat looks like in the first 6 to 24 hours. If the obstruction is not relieved, the symptoms become characteristic of post renal azotemia, including anorexia, vomiting, dehydration and depression. Weakness, collapse, stupor, hypothermia, hyperventilation and slow heart rate, then death. This isn’t a maybe. It happens. And it is a tough way to die. I will say it again. You know your cat better than anyone else. You live with your cat every day. If you see or hear something that just isn’t right, bring the cat in to get checked out immediately. Given what I just described, it is always better to be safe than sorry.  

The physical exam and treatment plan

The physical exam will determine whether or not we are dealing with an obstructed cat or a nonobstructed cat. Non obstructed cats will frequently present with a small, thickened bladder. For the initial presentation, a urinalysis is performed. If bacteria are seen in the urinalysis, a culture and sensitivity is performed. A dietary history is also performed to see if the cat needs to be moved to an acidifying diet. For cats with recurrent non-obstructive lower urinary tract signs, radiograph and ultrasound exams will likely be recommended. Signs will be managed with anti-inflammatory drugs (NSAIDs, glucocorticoids) anti-spasmodics (phenoxybenzamine), glycosaminoglycans, narcotic pain relief. Diet changes will also be suggested. Switching from a dry diet to canned diet to help increase water consumption and decrease urine concentration is recommended. Decreasing stress is another beneficial idea. 

The obstructed cat

This guy is different. There is urgency in relieving his obstruction. How this guy is treated depends on the shape he is in when presented. If he is alert and does not yet have blood values indicating the renal failure associated with urinary tract obstruction, he will be sedated, the obstruction will be relieved and a urethral catheter will be placed. However if he is depressed, lethargic, has a slow heart rate and/or is hypothermic, we must address his hyperkalemia (elevated blood potassium) before moving to anesthetize prior to placing urethral catheter. Hyperkalemia develops when the cat cannot urinate and get rid of potassium. The elevated potassium has effects on cardiac conduction. Remember an obstructed cat has a life threatening condition and without prompt treatment these cats can die. Depending on the severity of the signs, he may need to be hospitalized for a few days. The hyperkalemia is addressed in a relatively rapid fashion, followed by relieving the obstruction. Continuous fluids are administered over the next 24 hours as some obstructed cat will undergo something called a post-obstructive diuresis. Fluids and other supportive measures are needed for the next few days. The urinary bladder may have been so stretched from over distension that it needs to be expressed several times a day or an indwelling urinary catheter is left in place while the overstretched bladder muscle regains it’s tone.


If the causative factors to a particular cat’s FLUTD can be identified, then prevention may be possible. For example, the cat with a bacterial UTI can have his UTI treated and resolved. The cat with struvite stones can have them dissolved through diet and the cat with alkaline urine and struvite crystalluria can be treated with a urine acidification diet. For those cats that already have acid urine, a urine acidification diet will not help. However, they can be helped by feeding canned food to encourage water consumption resulting in more dilute urine. Some cats with idiopathic FLUTD can be helped with glucosamine and some with amitriptyline. 

Perineal Urethrostomy

There is a subset of cats, that will continue to obstruct no matter what dietary and medical means have been undertaken to try and prevent their repeated obstruction. For these cats, perineal urethrostomy is an option. This is a surgery, in which the penis is cut “lengthwise” deep towards the urinary bladder. The incision is carried forward until a wide spot in the urethra is reached. The urethra is then sutured to the skin. The advantage is that cats who have successful urethrostomies do not obstruct again. Because we have altered their host defense mechanisms, they are at some risk for bacterial urinary tract infections. I would propose that dealing with a UTI is better than dealing with an obstructed and potentially dead cat. 

 So, there you have it. FLUTD in a nutshell. And now a bit of trivia. As I sat here writing this, I was listening to Adagio for Strings. Do you know which movie soundtrack lays claim to the most infamous use of this piece?


Until next week……


Dr. Voorheis  

The Wacky World Of Bladder Stones – Episode 1

The wacky world of bladder stones – Episode 1

March 20, 2014

From the desk of Dr. Voorheis


 Here I sit again preparing for blog Thursday and thinking about what I see consistently in my practice of veterinary medicine. One thing high on that list is definitely bladder stones and urinary tract infections. Many of you are already intimately aware that some dogs and cats develop bladder stones. I’ve walked that path with many clients and critters over the years. This week, I will talk about the why and how of it all and provide some information about how we diagnose and treat this pesky problem.

As usual, let’s start at the beginning to set this up so that everyone can get a handle on the basics. I’ll start by explaining that urine is a complex solution in which salts such as calcium oxalate and magnesium ammonium phosphate can remain in the solution under conditions of “supersaturation“. Super what you say? Ok, think of it this way. Put some salt in water and stir. It dissolves, right? Put enough salt into the water and there will be a point where it can’t dissolve anymore. The water is saturated with sodium and chloride ions. And here begins “supersaturation”.

Many dogs and cats have urine saturated with these complex salts. This saturated urine has the potential to form solids from the dissolved salts. Crystalluria is a consequence of urine supersaturation and uroliths (stones) may form if crystals aggregate (get together) and are not excreted. Stones can damage the uroepithelium and result in urinary tract inflammation. Now we start to see signs including blood in the urine, frequent urination, straining to urinate, difficulty urinating and possibly even excessive licking of the genital area. This will predispose the animal to the development of a bacterial urinary tract infection, especially in dogs. If the stones lodge in the urethra, urine flow may be obstructed. If they form or lodge in ureter, urine flow may be obstructed and kidney damage can and will occur. Fortunately, most stones are found in bladder. Some are found in the urethra while only about 5% are found in the kidneys or ureters.

Just like people, these stones come in all shapes and sizes and are made up of different “stuff”.  We classify stones based on what “stuff” they are made of, i.e. their mineral content. About 40% of all canine bladder stones are made up of Calcium oxalate. Another   40% are made of struvite which is magnesium ammonium phosphate. About 5% are urate stones and another tiny 1% are cysteine stones. Another 1% are silicate and the rest are mixed or compounded. The numbers for the first two crystals are similar in cats. Calcium oxalate is slightly more common than struvite stones but they both make up more that 80% of feline bladder stones. Urate stones and dried solidified blood are found in cats more than in dogs. Bladder problems in cats are often lumped into “the feline lower urinary tract diseases”, or FLUTD. That is the subject for an upcoming blog because it is such a large subject and worthy of an entire blog. Besides, my feline clients are going to get a little tired of blogs about dog problems with a little cat thrown in for good measure. Oh believe me; cats have their own set of interesting issues. Coming soon to a blog near you….. FLUTD.

We know that certain conditions make it easier for crystallization of salts to occur and for the formation of bladder stones to happen. For example, having a sufficiently high concentration of salts in the urine and time in the urinary tract to crystallize can contribute to the creation of stones. Having a urine pH favorable for the salts to crystallize (come out of solution) and a center on which crystallization can occur can also contribute to bladder stones forming.  A high dietary intake of minerals and proteins coupled with a dog’s ability to produce concentrated urine contributes to “supersaturation” of urine with salts. Some dogs that don’t drink enough water have a greater chance of urolith formation. In certain breeds there is decreased tubular resorption of calcium, cystine and uric acid in the kidneys. Increased production of these salts is secondary to bacterial infection. There are different theories of urolith formation with the primary factor being the supersaturation of urine with salts vs. substances in the urine that promote or inhibit crystal formation. The most common bladder stones are:

• Struvite uroliths – also known as magnesium ammonium phosphate stones. Because most canine diets are rich in minerals and protein, canine urine frequently becomes saturated with magnesium, ammonium and phosphate. However, a UTI (urinary tract infection) is an important factor predisposing to the formation of struvite uroliths in dogs. Staphylococcus and Proteus are the most common bacteria associated with struvite stones. These bacteria contain enzymes which help turn the urine alkaline (by splitting urea) which decreases the solubility of struvite (so the crystals come out of solution easier). Bacterial infections produce organic debris available as a crystallization surface. These stones are more commonly associated with female dogs.  Interestingly, cats form struvite stones without concurrent bladder infections but cats produce far more concentrated urine than dogs do.  Most common breeds affected: Miniature Schnauzers, Miniature Poodles, Bichon Frises, Cocker Spaniels

•Calcium Oxalate Uroliths- The causes of formation of calcium oxalate stones are poorly understood. Hypercalciuria (high concentrations of calcium in the urine) is certainly a factor. In some dogs this occurs after eating. Others don’t reabsorb calcium in their kidneys resulting in excess urine calcium production. Treatment of some dogs with furosemide which is a diuretic can lead to formation of these types of stones.  Treating other dogs with corticosteroids where there is naturally occurring increased corticosteroid production can lead to formation of these types of stones as well. Increased dietary intake of certain vegetables high in oxalates, grass, and vitamin C may play a role in development of calcium oxalate urolithiasis.  There has been an increase in these types of stones over the past 15 years or so corresponding to the increased use of urine acidifying diets. These crystals come out of solution in an acid pH urine.  About 70% of the calcium oxalate uroliths are found in male dogs.  Most common breeds affected: Miniature and Standard Schnauzers, Miniature Poodles, Yorkshire Terriers, Lhasa Apsos, Bichon Frises, Shih Tzus.

bladderstone1          bladderstone2

•Urate uroliths -These stones are composed of ammonium acid urate. It is hypothesized that the hepatic transport of uric acid is defective in Dalmatians and some English Bulldogs because uric acid conversion to allantoin has been found to be decreased in them. In addition to decreased hepatic metabolism, in some Dalmatians the kidney does not reabsorb uric acid. End result is that the Dalmatian excretes about 10 times the urates that other dogs do, although urate stones form in only a small percentage of them. Male Dalmatians form urate stones at a much higher rate than females (like 16 to 1).  Other at risk breeds include the English Bulldog. Any dog that has hepatic insufficiency (esp due to hepatic cirrhosis, portosystemic shunts) is at risk for developing urate stones (although for these dogs bladder stones are the least of their problems).

•Silicate Uroliths – remember playing with jacks as a kid? Silicate stones are shaped like jacks. It is thought that silicate uroliths form due to dietary intake of silicates, such as eating large amounts of corn gluten or soybean hulls.  Remember in blog 2 on nutrition where I wondered when corn became bad? Well, this is a place that is could be a problem. Commonly affected breeds: German Shepherd Dogs, Old English Sheepdogs, Golden and Labrador Retrievers. Older dogs, 6 to 8 years of age.

•Cystine uroliths – cystinuria is an inherited disorder of renal transport and is the primary cause of cystine uroliths. More accurately stated it is a predisposing factor. Not every dog with cystinuria develops cystine uroliths. Dachshunds are the breed principally affected but it is also seen with Basset Hounds, Tibetan Spaniels, English Bulldogs, Yorkshire Terriers, Irish Terriers, Chihuahuas, Mastiffs, and Rottweilers.


Signs, Symptoms and Diagnosis

The signs depend on the number, type and location of the stones within the urinary tract. Most often, the stones are in the bladder so the symptoms are those consistent with cystitis. Symptoms include blood in the urine, frequent urination, straining to urinate, difficulty urinating and excessive licking of the genitals.

In male dogs, smaller stones may pass into the urethra causing partial or complete obstruction. This takes a mild to moderate problem and catapults it into a life threatening emergency. Urethral obstruction can be just as fatal to a dog as it is to a cat. Renal uroliths (kidney stones) are uncommon and can range from being asymptomatic to causing hematurina, chronic kidney infection and pyelonephritis. Ureteral uroliths can be asymptomatic or they can cause hydroureter. The condition is diagnosed from a combination of history, physical exam, radiographs and ultrasound. Sometimes radiographic contrast studies are done to find the stones. Finally, ultrasound examination confirms the findings.

Treatment possibilities

The general principle is prompt relief of any urethral obstruction. This can usually be accomplished by passing a smaller than normal urethral catheter and drawing urine out of the obstructed bladder. This process is called cystocentisis. Another method used is retrograde hydropulsion which is where a stone is forced back into bladder. Only rarely do we have to perform an emergency urethrotomy. With any treatment option, fluid support is key. After the initial wave of support, a decision must be made between surgical removal of the stones and medical dissolution of the stones. Next week I will discuss the treatment of each type of stone in detail but I can provide a bit of information now so that I don‘t leave anyone grasping for answers.

Bladder stones can potentially be eliminated by the dog without any intervention. However, if the stones are not eliminated in a few weeks they may cause damage to the bladder tissues or urinary tract. At that point, the bladder stones should be removed through surgery which is known as cytology.

In many cases the stones can be dissolved over a period of several weeks to several months by feeding the dog a specially formulated diet. Some of the diets I recommend are Hill’s Prescription Diet s/d, Royal Canin Urinary SO 13 or Hill’s u/d. This depends on which type of stone we are dealing with. There is also a drug called haloperidol that is often used. In some cases, feeding a diet such as Canin Vegetarian Formula may help prevent urate stones. There are no methods currently available for dissolving calcium oxalate and silica stones. However, diets and supplements can be used to reduce the risk of recurrence.

Surgical removal makes the most sense for urethral stones that cause obstruction and for bladder stones that fail to respond to a diet change and medication.

To end this week’s blog, I will say again that taking your dog to the vet for regular checkups is your best defense against big medical issues and huge vet bills. Stones that are caught early are much easier to deal with than those left to fester into larger problems. Your dog or cat will thank you for catching it early as it causes them much less pain and discomfort.

Next week…..bladder stones and UTI in cats…it’s a whole wide world of drama!

Until next week……..

Dr. Voorheis

Prevent A Litter, Fix Your Critter!

Prevent a litter, fix your critter!

March 13, 2014

From the desk of Dr. Voorheis


I’m sitting here contemplating at 5:00 am and recalling my wife’s recommendation, “Write about what you see”.  I’m thinking this is the best time of day, surrounded by 4 dogs in various stages of repose and two cats sharing the table with me (literally the cats are sharing the table with me – my cat clients know exactly what that means. The cats have seen fit to allow me to garner a small bit of space on this table for my laptop). More musings and sharing thoughts with clients and Mozart’s 527 Overture playing in the background. Well that is something most of you didn’t know and wouldn’t have guessed. Dr. Voorheis is a classic rocker who also likes classical music. And in the midst of all this, here is what presents itself to me for this week’s blog – spay and neuter et all. 

“Really Doc, you’re going to write on spay and neuter? Hasn’t that topic been done a million times?” The answer is obviously yes but new information is abreast! Remember my first blog when I shared that I am awake at 4:45am every morning reading veterinary journals, research papers and the like?  All in an effort to bring the most current knowledge to my clients and their critters? Well, of late I have come upon some very interesting findings that absolutely need to be shared with all of you. This will be different than what you have always understood to be true with regard to the topic of spay and neuter. New information tells us that we need to continue discussion and interpret new information in an appropriate light and pass that information on to clients. In addition, you will get my take on ovariohysterectomies and castrations as surgeries learning what is actually involved and when they should be done. But first, let’s start with what we have always known to be true.

Traditionally, my recommendation has been to spay and neuter at approximately six months of age. I have two main reasons for this recommendation. The first reason is to prevent unwanted litters. The second reason is to prevent mammary cancer.

 Mammary gland cancers are the second most common cancers outside of skin cancers. If a dog is spayed before her first heat, there is almost no chance of her developing breast cancer. If she is spayed before her second heat there is a 90% reduction in the incidence of breast cancer. If she is spayed after her second heat, there is no reduction in the incidence of breast cancer as compared to the unspayed female. There are several different types of breast cancer in dogs, just as there are with people. Some of these can be fatal. That is important to keep in mind as we discuss the new information below.

There is a third reason that I have recommended ovariohysterectomies and that is to reduce the incidence of pyometra which is an infection of the uterus. This infection is common in older female dogs. We have seen an unusual number of cases of pyometra at WBAH recently.

Traditionally, I have also recommended castration for male dogs at about six months of age. It reduces marking and roaming behavior as well as reducing the size of the prostate. This is important because benign prostatic hypertrophy (BPH) is common in dogs. Castration also removes the possibility of testicular cancer which is also seen in dogs. 

My traditional “con” when I talk about spaying a female dog is the tendency towards obesity. Metabolic requirements change as dogs age. Without the sex hormones such as estrogen, progesterone and testosterone, those metabolic requirements really change. One of the best ways to counteract that change is to feed less, almost from the moment the dog is spayed or neutered. Usually about 10% less will do it. In some dogs even less, and in some dogs no change is necessary. The second “con” to be aware of is that in a small percentage of spayed female dogs, they develop urinary incontinence with age. This is easily corrected with medication and in no way should be taken as a reason to not spay the female dog.

Without going in to too much graphic detail, I do want to briefly discuss the actual surgical procedure for a spay as well as a neuter. I believe that ovariohysterectomies are one of the more difficult abdominal surgeries that veterinarians perform. Surprised? It is a difficult surgery that is made to look easy by veterinarians. This is done through experience and practice. Removing a spleen or an intestinal foreign body or a bladder surgery is probably technically easier. The lifting and stretching of an ovary in order to position it for removal is actually a procedure that is difficult and requires a true “feel” for the technique.  As with any surgery, things can go wrong. But because we do them so often, veterinarians and clients often dismiss the difficulty of the surgery.

A castration surgery in the dog is a technically easier surgery to perform as the testicles are removed through a prescrotal incision and an abdominal incision is not used. Tissue handling is key with this surgery as prescrotal and scrotal skin is very sensitive. Many male dogs require an “E-collar” following surgery to prevent excessive licking which may traumatize the skin.

My goal with starting this blog was to educate both my clients as well as our entire community of clients here at WBAH. So, at this point I’d like to go over the reasons for recommending spays and neuters in the first place and we’ll also discuss the pros and cons. In addition, there were two journal articles published last year that started new conversations about ovariohysterectomy and castration. I will also give a response to those conversations that I deem appropriate. 

The first and most “well known” reason to spay and neuter is of course to save lives by preventing unwanted pregnancies and thus unwanted litters. To quote Dr. Janet Scarlett, Professor of Epidemiology at the College of Veterinary Medicine, Cornell University; “There is no disease or condition of companion animals that takes more of their lives than euthanasia.” In fact, no other disease even comes close. If any infectious disease caused the death of as many animals every year as euthanasia does, the veterinary profession would be in overdrive trying to find a solution to the problem. Yet euthanasia in shelters gets little attention outside of the shelter and rescue community.  Every year in the United States, 13% to 20% of owned dogs and cats have litters. Of those, 50% are “accidents”. The vast majority of those animals who have accidental litters are spayed later. The ideal situation is to spay them before they have a litter. Ten million dogs and cats are in shelters every year. Ten million. Of that ten million, 3 to 4 million are killed and most of those are healthy, adoptable animals. If we can reduce the incidence of delayed spay by 25%, we can reduce the number of unplanned puppies and kittens by 3 or 4 million, which turns out to be the number of animals euthanized in shelters every year. Interesting isn’t it?    

kittycage2   doggycage2

I think we can agree that spaying and neutering is important.  I also think that early spay and neuter is still an important concept that needs to be discussed. We’ll get to that in a moment. But first, let’s look at this new information I keep talking about. 

In 2013, two articles about two different studies were published by separate groups that set the “when to spay and neuter world” on its ear. These articles were presented by the University of California, Davis and at the University of Georgia, Athens.

 The University of Georgia study looked at over 40,000 dogs of all different breeds. The study showed that sterilization was associated with an increase in lifespan which was 13.8% longer in males and 26.3% in females. The study also showed decreased death from infectious disease but an increased risk of death from some cancers such as lymphoma, osteosarcoma and hemangiosarcoma.

 The UCD study looked exclusively at Golden Retrievers. It was a much smaller study, looking at only 759 dogs. There was an increased risk of hip dysplasia from 5% to 10% and an increased risk of cruciate rupture which was 5% in males and 8% in females compared to 0% in intact dogs. It is postulated that this may be due to changes in how the growth plates of these joints close in an intact dog vs. a dog with absent gonadal hormones.  Interpreting the portion of the study on cancer is more difficult. Female dogs who had undergone an early ovariohysterectomy had a higher incidence of lymphoma as well as splenic and liver cancers.  Intact females have a higher incidence of breast cancer than spayed females.  Interpreting these studies across all breeds of dogs will require more work but we think there is enough evidence to make changes in our recommendations for ovariohysterectomy and castration in dogs. This is especially true with large and giant breed dogs.  

 According to Julie Bulman-Fleming, DVM and Diplomate ACVIM (Oncology) of the Veterinary Cancer Group, allowing female dogs to have one heat is reasonable except for breeds that have high incidence of breast cancer. The report from UCD is actually challenged by the oncologists in light of the comments about MCT (mast cell tumors). They said that if dogs were spayed after the first heat but before the third or fourth heat, those dogs had higher incidence of MCT than the dogs spayed after or spayed before the first heat. Rottweiler breed male dogs kept intact for 2 to 2.5 years lowers incidence of bone cancer and orthopedic disease but increases incidence of dog to people biting.  

Those in the field of Osteo-Oncology have been heard to say that they would prefer the growth plates to be completely closed prior to a spay or neuter taking place.  If you spay or neuter your dog before the growth plates close, it prevents the growth plates from closing properly. For this reason, dogs that are spayed and neutered at a young age are often more prone to osteosarcoma (bone cancer), hip dysplasia, and other health problems. 

 The Bottom Line

For years, the veterinary medical profession has promoted spay and neuter. We have even promoted early spay and neuter. For WBAH that has meant recommending spay and neuter at about six months of age.  Ovariohysterectomy and castration is still recommended. No question about it. But there is a question about “when?”  This should be an individual discussion between client and veterinarian and specific for each breed and dog’s circumstances.  We do not want to get into a situation where this information is misinterpreted and clients forego spay and neuter.

What about small breed dogs? It turns out that the cancers discussed in this blog are fairly uncommon with smaller breed dogs. For the vast majority of the small breed dogs including the spaniel breeds, neutering before they have a heat is just fine. With male dogs, we are recommending neutering at the same time. With giant breed male dogs, waiting until the dogs have all the effects of the sex hormones is preferable.  In other words, secondary sex characteristics reduce the risk of bone cancer. Any negatives on that type of decision? The owners of these animals must be truly ready to handle a giant breed dog who is a fully mature male.  It won’t matter much if we have prevented a future cancer, if we are euthanizing the dog because it bit someone in the neighborhood.  

In general, large breed dogs should be allowed to mature and have one estrous cycle.  If we wait past two cycles, we will see increased breast cancer. If we go too early, we may increase the chance of cruciate injury. This calculates out to anytime after the first birthday, maybe approximately 14 to 16 months of age for large breed dogs and 18 to 20 months of age for giant breed dogs. My bet is that this information will result in a “more will be revealed” type statement. I have heard some clients say they will never spay their female dogs because they have heard some of this data. My opinion is that this is a huge mistake. Huge. One word – pyometra.


I alluded to this earlier. This disease is the reason for this week’s blog more so than any discussion on timing of spaying a female dog. Over the last two weeks, we have diagnosed and treated 5 cases of pyometra. What the heck is pyometra?  Stay with me….here comes more medical vocabulary.  

In intact (non spayed) females, the lining of the uterus changes with exposure to estrogen and progesterone. This change in the lining of the uterus is called cystic endometrial hyperplasia which you can think of as the uterine wall thickening over time. Pyometra develops secondarily to cystic endometrial hyperplasia. It develops when there is a bacterial invasion of the abnormal endometrium (uterine lining) which leads to intraluminal accumulation of purulent exudate. Where do the bacteria come from? They ascend from the vagina through the partially open cervix during the phase of the reproductive cycle called proestrus and estrus. This is what we commonly call “heat”. The most common bacteria that invades the uterus is E.coli. Most commonly affected are intact females greater than 6 years of age, although I have seen it in dogs as young as 3. Cats are more variable, and it is less common in cats.  The most common presenting signs are lethargy, increased thirst and in general not feeling well. It is so common that IF your dog is middle aged and is not spayed and she is presented as “sick” in my office, pyometra must first be ruled out over almost any other illness.

 Pyometras can be both open and closed. Closed means the cervix is closed and there is no vaginal discharge. Open means the cervix is open and there is a vaginal discharge. The diagnosis is made through history, physical exam, lab work, radiographs and ultrasound. These dogs can develop marked derangements in their CBC’s including markedly elevated white blood cell counts. They can also become anemic if their disease is chronic. The E.coli bacteria elaborate a toxin which impairs kidney function so they often present with signs of kidney failure as well. Pyometra is a life threatening condition. The treatment is fluid support, antibiotics and surgical removal of the uterus. There are cases in which medical (non surgical treatment) can be used, but many of these treatments do not result in cure and the animal ends up needing to go to surgery in the long run. In my opinion this is best treated surgically. The prevention to pyometra is to spay your dog before the 18th month of life or second heat of her life. By doing so, you will also gain the benefits of breast cancer prevention and all other things discussed in this blog above. 

It is clear that there are benefits to spaying and neutering our pets. The only controversy at this point is when the ideal time is for your dog or cat. Again, for small dogs we can recommend what we have been recommending for years. For medium and large dogs we can wait a little longer. For giant breed dogs we wait a little longer still. For our kitties, there is no evidence to my knowledge that the six month old spay/neuter causes health problems in cats. Honestly, if a decision must be made between spaying at 6 months and forgetting about it because it wasn’t on your mind, then go with the early spay. The benefits tend to out way the risks.

I realize this might be something new to your ears, but I hope that I have been able to provide the most up to date, valuable information possible so that you are all able to make the most informed and educated decisions for your critters.

Until next week…………..

Dr. Voorheis  

My Pet Is Allergic To What ?

My pet is allergic to WHAT?

 March 6, 2014

From the desk of Dr. Voorheis


“Wow Doc, last week I read all about fleas and all the drama they cause with my pet. Now you tell me my pet can also be allergic to the same stuff I am allergic to? Like pollen, dust mites and even certain foods?”

 The short answer to that is of course “yes”. This week’s blog will finish up our trilogy on allergies. Since we have extensively covered fleas, we will now talk about food allergies and atopy. As I sit at the keyboard to write this, my first thought is “I’ve got to be crazy to write about food allergies and atopic dermatitis in one blog.” My eyes are already crossing with the load of information that needs to be shared. A blog could easily be devoted to each of these. Heck, there are veterinary dermatologists who focus almost exclusively on atopic dermatitis. Attempting to distill this subject into something readable and understandable is this week’s challenge. But I’m always up for a good challenge as you know, so I shall give it the old college try! You’ll have to bear with me and excuse my language this week. No, I won’t be doing any cursing but there will be a ton of medical terms being used to try and explain this topic. It may get confusing but I will do my level best to explain it as we go along. Let’s start with some basic definitions:

 Atopic Dermatitis –  a predisposition to become allergic to normally innocuous substances, such as pollens such as grasses, weeds, and trees, mold, house dust mites, epithelial allergens and other environmental allergens. Susceptible animals become sensitized to allergens by producing allergen-specific IgE which binds to receptor sites on cutaneous mast cells. Further allergen exposure such as inhalation and more importantly percutaneous absorption causes circulating basophils (a type of white blood cell) and tissue mast cell degranulation. This is a type 1 immediate hypersensitivity and results in the release of histamine, heparin, proteolytic enzymes, cytokines, chemokines and many other chemical mediators.


 Food Adverse Reactions – Food Adverse reactions are itchy, non seasonal reactions associated with ingestion of one or more substances in the animal’s food. Pathogenesis (development of disease) is not completely understood with regard to immunologic (pertaining to the immune system) vs. idiosyncratic (pertaining to the individual animal in this case). Immunologic reactions are both immediate and delayed reactions to specific ingredients presumed to be type 1 and type 4 hypersensitivities.

 So why talk about these two together? The signs of each can look very similar. There is significant cross over in the distribution of “signs”. Typically, food allergy signs are not seasonal whereas atopic signs are seasonal. However, they do merge or blend. Why? Frequently, dogs and cats with atopic dermatitis have multiple allergies simultaneously which make their signs appear nearly year round. Couple that with frequent skin infections that also cause pruritus (itchiness) and you can have a seasonal dermatitis that affects the animal all year long.

 So now that we have the basics down, let’s talk about each topic individually and do a bit of comparing to point out the differences.

 Atopic Dermatitis

 In 2001, the American College of Veterinary Dermatology’s task force on Atopic Dermatitis, publishing in the journal Veterinary Immunology and Immunopathology, outlined significant change in the thinking of the pathophysiology (functional changes associated with disease)   of Atopic Dermatitis. Huh?

 Up until that point our understanding of Atopic Dermatitis went something like this: Atopy is an IgE- mediated disease like hay fever in people.

Inhaled allergen


Mast Cell Degranulation


Itchy skin

We now know that while the above may describe a small percentage of what happens in the atopic dog, this is not the main pathogenesis of the disease. Allergens are absorbed across the skin. Due to both genetic and environmental factors, there is epidermal barrier dysfunction. This leads to increased transepidermal water loss, deeper penetration of allergens and colonization of skin by bacteria and yeast. Yuck! There is some fairly complex pathophysiology that is happening in the skin of an atopic dog. Key proteins are affected, key lipids are deficient, the skin cells shed in an abnormal fashion and there are structural abnormalities in and between the skin cells.

 We know also now that IgE (antibody) is important but not essential. T-cell lymphocyte imbalance appears to be the key in atopic dermatitis. These T-cell lymphocytes produce cytokines. One of these inflammatory molecules is a molecule called IL-31. Blocking IL-31 is a key to treating the itching from atopic disease and a number of other allergic skin diseases.

 Remember, I told you there would be language this week! I wasn’t kidding. I hope you are all still with me. The bottom line is that we used to think that atopic dermatitis was caused by inhaled allergens such as pollens, house dust mites etc. We even had another name for it. We called it allergic inhalant dermatitis or AID which was easy to understand, BUT, that is not how it works. Atopic Dermatitis IS caused by pollens, molds, house dust mites and dander etc., but not by inhaling them. It happens when they cross the skin. Why? Simply because the skin is abnormal. The longer the dog or cat has untreated atopic dermatitis, the more abnormal the skin becomes.

What does atopic dermatitis look like?

Generally speaking atopic dermatitis starts early, often younger than 3 years of age. It can even start younger than 18 months of age. Occasionally, as young as a year. Affected dogs scratch their face, feet, the perineal area (area around anus and vulva), and the axillary (armpit) area. This condition tends to run in families. It is usually seasonal but can be year round depending on the allergen that is causing the problem. We also see recurrent skin or ear infections which are bacterial or yeast overgrowth. There is usually a positive response to corticosteroids. It seems that every year signs worsen. The number one sign is of course itching and scratching, especially at the areas mentioned above. Relapses are very common.


         Dogderm Canine Atopic Dermatitis         

Felinederm Feline Atopic Dermatitis

Differential Diagnosis– Atopic Dermatitis and food hypersensitivities can cause identical lesions. The main difference is that food hypersensitivity lesions should be non-seasonal. The problem here in Southern California is that we have long pollen seasons and as mentioned above, secondary skin infections conspire to make the dog itch all year long. Flea allergies cause itching to take place in different areas from those affected by atopic dermatitis or food allergy. Sarcoptic mange usually affects young or stray dogs and is relatively easy to treat with miticidal therapy. The difficult animals to diagnose are the “AND” dogs and cats. I think I mentioned last week that many dogs may have a flea bite hypersensitivity AND atopic dermatitis. They can have adverse reactions to food AND flea bite hypersensitivity. They can have all three, much to the dismay of many pet parents!

 When treating atopic dermatitis with injections of allergens or the new oral way, you are basically “vaccinating” or using the animals immune system to protect it against what it is hypersensitive to. Let me be very clear. Injections need to be given for a long time to determine whether they are effective or not. This could mean an entire year.

 Allow me a quick word about bathing the atopic dog. Statistics show that frequent bathing reduces the amount of corticosteroids needed in the dog’s lifetime by 50%. The challenge with this is you wash off flea control which is a crucial part of the treatment regimen as well. The solution is to use the oral medications for flea control with these dogs.

 Adverse Reactions to Food (Food Allergy)

 You wouldn’t know it by the multi-billion dollar pet food industry but food hypersensitivity represents only 5% of all skin disease and 10% of all allergic disease in dogs and cats. Get ready for another “huh?” Generally speaking, there is an immune reaction between one or more glycoproteins (allergens), either before or after digestion. Sensitization may occur at the gastrointestinal mucosa, after the substance is absorbed or both. Some specialists theorize that juvenile parasitism contributes to damaging intestinal mucosa resulting in absorption of allergens and subsequent sensitization.

 The signs of food hypersensitivity mimic any of the other hypersensitivity reactions such as flea or atopy. Most common are itching in any location on the body and chronic ear infections. They can look exactly like atopic dogs. Occasionally, they will also have gastrointestinal disease, vomiting, diarrhea, more frequent bowel movements and flatulence.  Not every dog with skin disease associated with adverse reactions to food has gastrointestinal signs so the absence of GI signs does not rule out food hypersensitivity.   In cats, severe facial pruritus is a hallmark of food hypersensitivity. As with atopic dermatitis, chronic skin infection with both malassezia (yeast) dermatitis and bacteria are common sequelae to food hypersensitivities.


 felinefood1   Feline Food Allergy    felinefood2  

Differential diagnosis:

Flea bite hypersensitivity, atopic dermatitis and scabies are the main differentials. This is interesting because this differential diagnosis list is exactly the same as the differential diagnosis list of atopic dermatitis. See what I did there?

 “Ok Doc, I get your point. Apparently, food hypersensitivities and atopic dermatitis can look the same. Can’t you just run a blood test for this? Get the diagnosis? I know I found a laboratory on the internet that can do exactly that.”  Unfortunately, there is NO correlation to serum antibody and food hypersensitivity. None. Not at all. Did I say none? Good.

 This is the point in the blog where I issue this plea. Patience and lots of it. To solve complex dermatology problems takes time. One of my many jobs is to explain why it takes so much time. These guys don’t come in to the office waving a flag or poster that says “I’ve got a food allergy” or “I have atopic disease”. Remember that they may have a combination of flea allergy, food allergy and atopic dermatitis. Many have secondary skin infections which by themselves cause itching. Remember the allergic threshold term from a couple of blogs ago? The goal is to diminish as many of the factors causing itching as we can to get to the bottom of it.

 When a dog or cat is presented with clinical signs that point to an Adverse Food Reaction or Atopic Dermatitis, a number of things will be done to try to start helping right away. Smears and scrapings will be made to examine the skin for bacteria and yeast infection with appropriate antibiotics and antifungals selected for treatment. The animal’s flea control regimen will be improved upon.  A detailed dermatology history will be performed.  The process of determining whether this is a food related dermatitis or atopic dermatitis will begin at that point.

 It usually starts with a food trial. “Whoa, wait a minute Doc. You have been harping on the fact that food is the least common of the main allergy groupings. So why start with a food trial?” Many dermatologists make the statement that “we might as well because you have to feed the animal anyway”. We don’t have to do it that way, IF the signs fit Atopic Dermatitis which means strong seasonality, intradermal skin testing or blood testing could be done first. Most of the time however, we start with a food trial. 

 A food elimination diet is considered the definitive test for food hypersensitivity. There are a few ways this is done. Many dermatologists believe that having an owner cook for the dog for a period of 9 weeks is the best way to perform a food trial. Other’s believe that using a prescription diet (Hill’s Z/D, Royal Canin Anallergenic), whose proteins have been broken down into fragments so small that the body cannot mount an immune response, is the best way to perform a food trial. In the former, a solitary protein and a solitary carbohydrate are chosen. These must be foods that the animal has never been exposed to before. In a 9 week food trial, nothing and I repeat nothing else can pass the lips of the dog during the trial but the designated food (Z/D, anallergenic, or the solitary protein/CHO that owner is cooking for dog). Nothing else – No treats. No table scraps. No nothing.  Chewable medications, Pill Pockets, treats, are all culprits in negating a food elimination diet and must not be offered.

Changing from one brand of dog food to another brand of dog food that the nice young man at the pet supply store recommends does not in any way constitute a food trial. No way, no how.  

 Now about that trendy gluten/grain free thing. It’s our latest kick in this country. Most of the allergies to foods in dogs and cats are due to hypersensitivities to proteins, not grains. Yes, there are proteins in the hulls of some grains the biggest culprit being wheat. But grains and glutens constitute the smallest fragment of adverse reactions to foods and remember that adverse reactions to foods are the smallest percentage of hypersensitivities that dogs have. Although they are second to flea bite hypersensitivity in the cat.

 If any skin infection has been controlled and the dog or cat has completed the 9 week trial and remains itchy, it is safe to say it doesn’t have food hypersensitivity. If the food trial results in a dramatic improvement, we can either challenge the dog with its old food, continue to feed it the prescription diet, or add single ingredients back into the elimination diet waiting for ten days for each single ingredient to determine whether or not the ingredient stimulates the allergic response. So what about those guys that didn’t improve? Time to move to diagnosing and treating atopic dermatitis.

 The basic mainstays of diagnosis are Serologic Allergy Testing and Intradermal Skin Testing. It is my belief that Intradermal Skin Testing is best performed by someone who does it every day such as a board certified dermatologist. Skin Testing is when a large area of skin is shaved and then a large number of allergens are injected into the skin and the reaction is measured. Serologic testing is simply drawing blood and submitting to one of a couple of labs in this country that measure the immune response to over 120 allergens. At our hospital we use either of two laboratories with strong reputations in the field of veterinary dermatology.

 The idea is that the 10 strongest reactors of either skin testing or blood testing are then put into a vial and injected into dog in gradually increasing dosages in an attempt to reduce their sensitivity. This form of treatment successfully reduces pruritus (itching) in 60-80% of dogs and cats. The downside? Response is slow; it often takes 6 to 12 months to see a true response.

 There is a new idea beginning to take hold in the field of veterinary dermatology. It is called Regionally Specific Antigen Therapy. In this model, no allergy testing is done. Rather, a set of antigens is chosen for the region of the country in which the animal lives. This is based on the knowledge that there is considerable cross reactivity between the various allergens. That is, that protection against ragweed pollen might also protect you against some other inhaled pollen. This new form of treatment offers the advantage of being just as effective as and less expensive than traditional treatment modalities. The allergens are either administered as injections or oral medication.

 Other aspects of treating atopic dermatitis include soaking in cool water, water plus emollients, frequent bathing which removes allergens and reduces infection and the ever popular use of topical treatments to try to restore the normal skin barrier. Some of those products are Duoxo Seborrhea Spot On and Allerderm Spot On.

 Successful treatment of either food allergies or atopic dermatitis may also involve the use of omega 3 Fatty Acids as an oral food supplementation and the use of either the new IL-31 blocker Apoquel or corticosteroids to manage the itching. Apoquel is the newest drug to fight inflammation. It is not a corticosteroid and has none of the corticosteroid side effects. It is very effective and specifically developed for atopy. It has definitely shown to be effective with flea allergic dermatitis and I suspect it will be just as effective for food hypersensitivities too.

 Dogs and cats that have adverse reactions to food, or that have atopic dermatitis are the most challenging skin disease cases that we see. They are time consuming and require a ton of patience. But with patience, time and painstaking willingness to go through a process, these animals can be well managed.

 Okay, allergy education complete. You all get at A+ for sticking with me through this very intense crash course. I hope I have provided some valuable information. Thanks again for reading my blog each week. It really has become quite a labor of love and your comments are certainly appreciated and welcomed!


Until next week……


Dr. Voorheis

Fleas – Those Blood Sucking Little Vampires!

Fleas – those blood sucking little vampires

February 27, 2014

From the desk of Dr. Voorheis

To produce a mighty book, you must choose a mighty theme. No great and enduring volume can ever be written on the flea, though many there be that have tried it.” (Herman Melville)

Well, I’m going to try it! But you might be asking “are you kidding me Doc? A whole blog devoted to fleas?” Yes, absolutely! With regard to the amount of disease and visits to the veterinarian regarding fleas and flea related illness, I could devote two blogs or more! You’ll come to realize that I am NOT a fan of fleas…nor should you be. They are the enemy.


From Wikipedia: Fleas are wingless insects (1/16 to 1/8-inch (1.5 to 3.3 mm) long) that are agile, usually dark colored (for example, the reddish-brown of the cat flea), with tube-like mouth-parts adapted to feeding on the blood of their hosts. Their legs are long, the hind pair well adapted for jumping: a flea can jump vertically up to 7 inches (18 cm) and horizontally up to 13 inches (33 cm),[3] making the flea one of the best jumpers of all known animals (relative to body size), second only to the froghopper.

Charming, right? That’s just the beginning. Historically, fleas have been the harbinger of tragic, wide spread illness. The most famous instance was “The Black Death” or “Black Plague” which decimated Europe in the mid 14th century, wiping out roughly 1/3 of Europe’s population. More than 75 million people lost their lives. This plague was caused by a bacterium called Yersinia Pestis and you guessed it, it was carried by fleas. These fleas lived on rats that traveled on merchant ships from the Far East to Europe. We still see plague today, such as the bubonic plague, which is still caused by the Yersinia Pestis organism. And yes, this is still carried by fleas. The charming little flea that carries it is found on ground squirrels and other rodents. Every now and then, we will read about a campground in the local mountains being shut down because plague was found in a ground squirrel. The good news is that the disease is now easily treated with the tetracycline class of antibiotics.  

“Ok Doc, nice history lesson. But what about my pets?” Nope, not yet. Sun Tzu’s second century book, “The Art of War”, tells us to “know our enemy”. So let’s learn a little bit about the flea that likes to make a convenient meal of our pets.

The most common flea that affects both our dogs and our cats is the cat flea, Ctenocephalides felis. Virtually all of the fleas affecting both dogs and cats in the United States are the cat flea. Fleas have 4 life cycle stages which are eggs, larva, pupa and adult.

Below, you’ll find a picture of an adult flea. In the words of a line from my favorite movie, Ghostbusters, “it’s an ugly little spud isn’t it”?


So, what came first, the chicken or the egg?  I think we should start with the egg and work our way forward. 

Eggs:  These are tiny white fleas eggs can hatch in as little as two days, or as long as few weeks depending on environmental conditions. The eggs can be found where the pet sleeps, on bedding, carpet, floor boards etc.

Larva: The larval stage is skinny, long and semitransparent. It has small hair on its body. They eat the feces of adult fleas, made mostly of dried blood. Depending on the amount of “food” and other environmental conditions, this stage can last from 5 to 18 days. The larva then spins a cocoon.

Pupa: The cocoon phase. This is the last phase before emerging as an adult. The adult flea can emerge in as little as 3 to 5 days, or it can stay in the cocoon phase waiting for the right time to emerge.

Adults: Emergence is stimulated by vibration, warm ambient temperatures, high humidity and increased CO2 levels. They are about 1 to 3 mm in size, reddish brown to black in color and possess powerful hind legs to jump and run through the animal’s hair coat. Adult fleas begin feeding immediately once they acquire a host and defecate flea feces (digested blood) in as little as 8 to 9 minutes. Adult cat fleas require blood to produce eggs. This is the only stage in the life cycle when the fleas live on the pet. They live 4 days to a couple of months and can lay up to 50 eggs a day. Yikes!

So let’s add it up:

  • Eggs can hatch in as little as 2 days.
  • Larval stage lasts from 5 to 18 days
  • Pupal stage – 3 to 5 days
  • Adult – A flea can go from egg to adult producing eggs in as little as 11 days in optimal conditions.

Optimal living conditions for an adult flea can be defined as Southern California spring, summer and fall. Less optimal is winter time, however we NEVER get cold enough to stop fleas altogether.


So what’s the big deal?

“So what is the big deal Doc?  A little itch? Fido scratches a bit? Big deal.”  

It actually is a big deal. Close to 70% of the itching, scratching dogs that are presented at a veterinary hospital have flea bite dermatitis or flea bite hypersensitivity which we commonly call flea allergic dermatitis.  That is a huge number of cases. To be more accurate, flea bite dermatitis is caused by direct irritation at the site of the bite while flea bite hypersensitivity is caused by immediate (type 1), delayed (type 4), and cutaneous basophil hypersensitivities.

Have you ever seen tapeworm segments in the feces of your dog or cat? I know, gross! Dogs and cats get tapeworms from ingesting fleas. Fleas get tapeworms from the flea larval stage ingesting tapeworm eggs. If your pet has tapeworms, your pet has fleas. Bottom line, end of story. I told you fleas were the enemy!

Every year, we see kittens, puppies, and less mobile older dogs that are suffering from such a large flea load that they are actually anemic. In case you didn’t catch that I will say it again – ANEMIC….caused by fleas! Those blood sucking little vampires.

Flea and other parasite control is essential to your pet’s good health. Essential. I will describe the best methods of flea control below, but for now I will talk about the skin disease caused by fleas. It isn’t pretty and it can make your pets absolutely miserable.

Flea bite dermatitis and flea bite hypersensitivities are the most common form of skin allergy in the dog and cat, comprising 70% of all skin allergies in dogs, and approximately 50-60% of all skin allergies in cats.

Flea saliva contains histamine like compounds, several complete allergens and haptens which are substances that when combined with other molecules act like allergens.

Do you remember my description of the allergic reaction? Type 1 reactions are a form of acute inflammation that results from the interactions of antigens, i.e. in this case the proteins in a flea’s saliva with mast cell bound IgE which is a type of antibody. This leads to the release of mast cell contents which in turn cause acute inflammation. This excessive release of inflammatory mediators is also happening with other cells in the skin like white blood cells called eosinophils and basophils. The end result is a very itchy, miserable dog.

Flea allergies are also type 4 hypersensitivities where the itching can occur days after the bite. This type of inflammation is mediated by different cells called T-cells.

The important take home point here is that allergic reaction from flea bites can be immediate, and can also be delayed. You don’t have to find fleas on your dog or cat for the pet to have flea related skin issues. That is worth repeating. Remember my second blog, in which I talked about the microbial world we all live in. Somehow, we humans would like to think we are above all that and we extend that vision to our pets. As a clinician, I am not judging you if your dog or cat as a flea allergy. I don’t make an assessment as to your housekeeping or general character if the dog or cat has an allergy to the bite of a flea. Many people are actually offended when I talk about flea allergies. Comments I often hear are things like “my groomer has never seen fleas on my dog”, “I’ve never seen a flea on my dog”, “my cat couldn’t have fleas – it’s in the house all the time”, “I give yeast tablets so they can’t have fleas”, “I add garlic to the food to repel fleas”.

All and I repeat all dogs and cats in Southern California, unless they are residing in a plastic bubble, will pick up fleas. Some more than others, and some with bigger reactions to fleas than others.

What does a flea allergy look like?

The textbooks say the age of onset of a flea bite hypersensitivity is usually 3 to 5 years. My experience is that I have seen flea allergies start as soon as 15 months of age and in some cases even younger. They tend to worsen with age, with fewer and fewer flea bites required to stimulate the allergic response. It tends to develop with intermittent exposure to fleas as opposed to continuous exposure. The same holds true for cats. Please do not take that as a reason to not treat for fleas.


Some signs to look for are:

  • a mild rash (small red bumps)
  • broken hair follicles (from chewing)
  • significant itching on the BACK half of the body

Hair loss and itching occur especially in a “triangular patch”. This looks like a backward “V” extending from the base of the tail to the middle of the back. The back of the thighs, the tail and the area of the belly between the rear legs are also affected. The incisor teeth will even wear down with chronic chewing.  


Secondary skin infections with both bacteria and yeast organisms are common especially with chronic conditions. These secondary skin infections complicate treatment, requiring additional treatment to resolve the patient’s discomfort.

Dogs with flea allergies will also develop painful “hot spots” or “pyotraumatic dermatitis”. These are deep skin infections and inflammation associated with the trauma of scratching an itchy spot.

In cats, this often takes on the appearance of a skin condition called “miliary dermatitis” which can be generalized over the cat’s entire body or confined to the same area as the dog seen above. The other place we see it is the head and neck region. Cats also get a condition called “eosinophilic plaques” which can be caused by flea bites.


Differential Diagnosis

Whenever a case of “itchy skin” is presented to me, I have a mental checklist to go through. Many dogs and cats have multiple allergies but fleas and flea bite hypersensitivity must be brought under control prior to tackling those other conditions. So I have to bear in mind that the apparent flea bite hypersensitivity in front of me could be a food allergy or atopic dermatitis masquerading as a flea allergy. I may require skin scraping to determine whether or not one of three different types of mange may be involved, those being sarcoptic mange, demodectic mange and chelyetiella mange. I also may perform cytology on the skin to determine the level and type of secondary skin infections contributing to the skin disease.

It is my experience, that flea bites and flea bite hypersensitivity are not glamorous diagnoses. Folks would much rather have their dog allergic to food than fleas. Think of it, a brightly lit store with an “oh so friendly” helper in a blue shirt, solving your dog or cat’s problems with a bag of food. Unfortunately, things don’t usually work that way.


There are two forms of treatment. First, we must treat the affected pet. The dog or cat brought in with the kinds of signs mentioned above is miserable. We must bring some relief to that patient. Flea control and flea elimination will be a critical factor in treatment. However, the dog or cat is itchy now. Relief of itching can be accomplished by using a variety of anti-inflammatory medications. Relief of itching may also involve use of antibiotics and antifungals to treat secondary bacterial and/or yeast infections. Relief of itching may be brought about by the use of topical or systemic corticosteroids, omega-3 fatty acids, anti-histamine therapy, or the new medication Apoquel. Corticosteroids and Apoquel are used to get the majority of the inflammation under control while flea control measures are undertaken. In mild cases, relief may be achieved by a combination of topical corticosteroids, omega 3 FA’s and flea control. In more significant cases, systemic corticosteroids or Apoquel will be needed to bring the inflammation under control and relief to the pet. Traditionally, that control may look like an injection of a corticosteroid and oral corticosteroids to bring about relief. In January of this year, a new medication to control skin inflammation called Apoquel was released and it has been proving very effective at controlling skin inflammation and itch thus far. Its cost per pill is higher than corticosteroids, but is about the same as what you would pay if an injection of corticosteroids was given along with a prescription to take home.

A word about corticosteroids. It is my belief that the judicious use of corticosteroids is safe and effective. The key word is judicious. Most of us in veterinary medicine are reluctant to use them long term because over the long haul they can have side effects. Appropriate management involves discussion with your veterinarian and monitoring your pet. It may include laboratory work to assess how the animal is handling the medication.

For the most part, both Apoquel and corticosteroids can be used the same way in flea bite hypersensitivity reactions. We use them to get the inflammation under control and use our flea control to keep things that way.

What about omega-3 fatty acids and/or antihistamine therapy? Omega 3 fatty acids work their way into an inflammatory cascade, blocking the body’s ability to make arachidonic acid which is a key component of inflammation. This is effective in both arthritis and skin inflammation but slow to work and certainly cannot “hold” the severely affected dog. The dose is 180 mg of the EPA fragment per 10 lbs of dog per day. This means a 40 lb dog would require 4, 1000 mg fish oil capsules per day. There are super concentrated forms available.

Antihistamine therapy? We all use it to try to decrease the amount of corticosteroids used to control itching. I think if you actually pin down a veterinary dermatologist they will admit that antihistamines are not very effective at all in controlling itching in the dog and cat. This is mostly because histamine is not the main chemical mediator of inflammation in our pets.

What about cats? Can we use this new anti-itch medication in cats? Sadly, no. Once again, I must remind everyone that cats are not small dogs. Dogs and cats have entirely different metabolisms and this new drug is not tolerated in cats. And while we are on the subject, cat flea control should NEVER EVER be applied to a dog and dog flea control should NEVER EVER be applied to a cat. Did I say NEVER EVER? Good. Cats bring the added challenge of sometimes being a little reluctant to be medicated. Again, corticosteroids may make up an important part of inflammation relief. However, the type of corticosteroid and the method of its administration mandate a discussion between veterinarian and client. In some middle aged and older cats, corticosteroids may not be used and a drug called cyclosporine will be substituted.

The prime aim of treatment of flea bite dermatitis and flea bite hypersensitivity is flea control. Appropriate treatment will be directed against certain life cycle stages mentioned above. Remember that we and our animals live in a microbial world (second blog) and the organisms we are trying to eliminate and control will, over time, develop resistance to the products designed to eliminate them. In fact, continued use of these products will exert selective pressure on flea populations and will most likely result in resistant flea populations.

New populations of fleas are being brought into our yards by untreated animals, feral cats, raccoons, and opossums. In suburban United States, the raccoon is a main carrier of fleas.

There is no question that those of us on the frontlines of daily flea treatment believe we are in a situation that is worsening with regard to flea related illness. There are some basic principles that need to be followed if we are going to achieve success in treating fleas and flea bite hypersensitivity.

1. Every animal in the household, symptomatic or not, needs to be on a monthly flea control program. That includes the outside dog with no skin problems and the cat who “never gets fleas” along with his brother who “always gets fleas”. Please understand that in that situation, the cat who “never gets fleas” may have just as many fleas as the cat who is symptomatic for his/her flea allergies.  That can be daunting for those of us who have multiple cat/dog households. The bottom line whether you like it or not is: Everybody. Every month. Did I say every animal in the house every month? I hope so.

2. Understand that the only life cycle stage of the flea that lives on the pet is the “adult”. The larva, the pupa, and the eggs are in the environment. Where? Here’s a hint: wash the bedding where the dog or cat sleeps at least once a week. Vacuum your carpets at least once a week.  Fleas hide and do their business in these areas.

There is a dazzling array of flea products with more being produced every year. In addition there is a large number of products that are claiming to be “just like” a well known or better product with slick packaging store prices. Many of these are recycled products that the veterinary profession knows are ineffective and in some cases not all that safe.

The following is an abbreviated list of products that are available. I will make some recommendations but please keep in mind that as it is with vaccinations, not every animal needs the cookie cutter recommendations for flea control. Depending on housing, skin problems and multiple animal households, we make different recommendations for your pets. I prefer to treat the individual pet and not make blanket recommendations.


Program, Advantage, Advantix, Advantage-multi, Advantage II, Topspot, Frontline, Frontline Plus, Parastar, Parastar plus, Knockout, Ovitrol, Adam’s Spray, Biospot, Preventic Plus, Revolution, Sentinel, Capstar, Promeris, Vectra 3D, Comfortis, Trifexis.

For some dogs and cats with flea bite hypersensitivity, a topical adulticide applied monthly to every animal in the house will work and will be effective. The key is every animal, every month. There are veterinary parasitologists who recommend that you rotate products to try and prevent resistance to product. For example, I might recommend Revolution applied every month to all pets in the house for six to nine months and then rotate in with Comfortis for six months. The same thought process can still be used using Frontline or Advantage, although for these two older products I am currently recommending the application frequency be changed to every 3 weeks.

For dogs with the severe flea bite hypersensitivities, consider using two products. For example, use Revolution once a month, e.g. on the first of every month along with Sentinel every month, e.g on the 15th of every month. The revolution would act as an adulticide and the Sentinel as a flea sterilizer. Fleas that lay eggs after ingesting the blood of a dog who takes Sentinel will not hatch.

There are some dogs whose flea bite hypersensitivities have resulted in such severe skin disease that frequent bathing will be needed. “Wait a minute Doc, am I going to wash off product”? Yes. For those dogs I would recommend Comfortis once a month AND Sentinel once a month. The products will still be on the dog even if they have to be bathed once a week. For severely affected cats, very similar recommendations in that Comfortis and Program should be used.

The bottom line is a conversation with your veterinarian is going to be needed to decide together what flea products are necessary in your home, for your pet or pets.

Treatment failures

The number one reason for treatment failures is interrupted or intermittent flea control. Poorly applied or inadequately applied product is also a big problem. Another epic failure is treating only the affected dog or cat and ignoring the pets who have fleas but don’t have flea allergies. How many people apply monthly product, but give their dogs and cats weekly or biweekly baths? Poor products are another problem. Those products being marketed as “just like” the better products mentioned above, but somehow the magic of Wal-Mart or Costco makes them cheaper. Don’t believe it. Problem is they contain product that we discarded as effective more than 20 years ago. Recycling and repackaging ineffective product has become commonplace. Buying these products saves a few dollars now but believe me when I tell you that you will spend A LOT more money later treating the dog or cat that is now infested and miserable because the bargain stuff didn’t work properly. You get what you pay for, buyer beware. Your pet’s well being is worth a lot more than a few dollars saved, is it not?

As I mentioned above, a flea allergy is not glamorous.  It seems like people would sooner have their pets allergic to food or have atopic dermatitis. Atopic what?  We shall talk about these two topics next week. I hope you have enjoyed your crash course on fleas and flea prevention…on a parting note I will say once more….. : Everybody. Every month. Did I say every animal in the house every month? I hope so.

Until next week…………………….

Dr. Voorheis

Those Darn Allergies!

Those darn allergies!

February 20, 2014

From the desk of Dr. Voorheis

Allergies. They make us sneeze and cough. They make our eyes burn and our skin itch. They give us headaches. They can even cause severe allergic reactions to things like certain foods, medications or even insect bites. They are inconvenient at best and miserable at worst. But did you know that our pets can have allergies too? Indeed they can! The main difference is that when pets are allergic to something, they usually itch instead of cough and sneeze etc. Allergies are one of the most common things we treat at WBAH. We see it day in and day out with so many of the critters entrusted to our care. And just as it is with humans, allergies cannot be cured but they can be successfully treated and managed.

“Allergies” is a massive topic to take on in one blog entry.  I think the best approach, so as not to overwhelm anyone, is to provide an overview this week and then concentrate on the specifics over the following 2 weeks. By then you will know everything you ever wanted to know about pets and allergies! It is interesting information and you will be an expert by the time we’re done.

You might recognize some of the terms used in discussing allergies from my entry on vaccinations a few weeks back. Skin allergies are the most common type of allergy in my patients, so my blog will focus on skin allergies over the next two weeks. I will also touch base on allergies that affect the GI tract (gastrointestinal). So let’s get started with that overview!

In the world of an immunologist, an allergy is a type of “hypersensitivity reaction”.  Immunologists classify hypersensitivity reactions at type 1, 2, 3 or 4. Hypersensitivity reactions 1 and 4 are concerned with the skin. Type 1 is called an “immediate” hypersensitivity and type 4 is “delayed hypersensitivity”. Unfortunately, knowing something is an “immediate” hypersensitivity does not tell us WHAT that hypersensitivity is caused by. Clinicians like myself classify allergies by type of allergy. Examples are food, atopy (pollens, molds, house dust mites), contact dermatitis or proteins of foreign creatures (fleas, insects etc). To help us decide what categories an apparent allergy falls into, we consider the location on the body where the animal is itching. Here is a more detailed breakdown:

Type 1 hypersensitivity

You’ve heard of people who carry an epinephrine injection where ever they go because they might die if stung by a bee? In veterinary medicine, life threatening allergic anaphylaxis is uncommon.  I’ve seen it very rarely and most often I see it associated with a vaccine reaction. With better vaccines available today, it is extremely rare. Many skin allergies, from flea allergies to atopy, fall under this category. So what is Type 1 hypersensitivity? In a nutshell, this type of hypersensitivity is also commonly called an allergy, although it is not the only type of allergy. If an immediate hypersensitivity reaction is life-threatening, it is called allergic anaphylaxis or anaphylactic shock. This is probably a term that is familiar.  More about how and why this happens in parts two and three of the allergy blog series.

 Type 2 hypersensitivity  

I will not be discussing this in detail in the allergy blog. In brief, these reactions are called cytotoxic hypersensitivity.  These occur when antibodies (and some other proteins) destroy normal cells. Examples of this are the destruction of transfused red blood cells when administered to a mismatched recipient (blood transfusion gone wrong). Certain drugs and infectious organisms can bind to the red cell membrane and change its shape. Thus, it is no longer recognized as “self” and is now considered “foreign and dangerous”. So the cell is removed from circulation, resulting in hemolytic anemia (low red blood cell count). However, most cases of IMHA (Immune Mediated Hemolytic Anemia) in dogs cannot be linked to a medication or infection.

Type 3 hypersensitivity  

This is tough stuff.  With this, we are dealing with reactions or immune complex reactions.  Complicated immune reactions occur when antigens and antibodies combine to form immune complexes. Immune complexes can trigger severe inflammation when deposited in large amounts in tissues. In a localized form, this can be a cause of “blue eye” which is seen in dogs infected with canine adenovirus type 1 or vaccinated with a vaccine that contains adenovirus type 1. Cases of blue eye from vaccinations resolve spontaneously in dogs. Immune complex disease is also responsible for a type of kidney disease called glomerulonephritis.

Type 4 hypersensitivity

When injected into the skin, some antigens induce a slowly developing inflammatory response called a “delayed” or type four hypersensitivity. These reactions are mediated by T Cells which are a type of white blood cell. A good example of delayed hypersensitivity is the TB test. Some of you may remember how you have to go back to have a TB test “read”. This reaction falls under the category of “delayed” or type IV hypersensitivity. Skin allergies, allergic contact dermatitis, flea allergies and atopic dermatitis can also be delayed.

So as you can see, there can be considerable cross over between type 1 and type 4 allergies. Knowing whether something is type 1 or type 4 doesn’t change much about how we treat it. Nor does it help too much to know the reason behind why an individual animal is “itching”.

Location and Season

Ok, so far we have learned that if we are talking about skin allergies, we are talking about type 1 and type 4 hypersensitivities. We also now know that knowing what type of allergy it is doesn’t help too much in diagnosing what our pets are allergic to. But how about the location of the itching? Or time of year? Do these things help at all in our quest for answers? In general, these things can help anywhere from a little to a lot. It turns out that “location, location, location“ is important in more than just real estate. It’s also important in diagnosing what your dog is allergic to.

It is important to note that these are general guidelines and there is cross-over. This is by no means an exact science.  In other words, a dog with a food allergy can look like a dog with atopy (allergy to pollens, molds, house dust mites, etc).  And a dog with atopy can look like a dog with a flea allergy. In addition, dogs can have both a flea allergy and atopic dermatitis. They can have a flea allergy along with a food allergy. Some dogs hit the lotto, and have allergies to all three! Tons of fun for mom and dad! What about our kitties? Same holds true for them unfortunately.

So what do I mean by “location“? It turns out that where a dog licks and itches, gives us a big hint as to what is causing the itch.  Let’s start with the “front half” of the dog vs.  the “back half” of the dog and ask ourselves where the signs/symptoms are appearing. If the dog is itching at the back half meaning the area just in front of the base of the tail and sometimes extending in a V shaped wedge along the middle of the back as well as the back of the thighs and the underbelly then that dog has a flea allergy. Period, end of story. Ever wonder why this particular problem is far more prevalent in warm seasons than winter time?  It’s because a flea can rapidly go through an entire life cycle in warm weather. I will go into far more detail about flea allergies in next week’s blog.  Fascinating stuff!

What about the “front half” of the dog? In general, dogs that rub their face and ears and lick the tops of their front feet (and in some cases their rear feet as well) are giving us strong hints that they may have atopy or a food allergy. Let me be very clear here. There is no way to tell the difference between an atopic dog and a food allergy dog based on those signs. They look exactly the same. Seasonality may come into play for some atopic dogs (those dogs allergic to certain pollens that are only in high numbers during certain times of the year) but some atopic dogs may be allergic to house dust mites and they have year round signs.

Now, a word on food allergies. Walk into any pet supply store. There are an overwhelming number of dog and cat foods available which I mentioned in the blog on nutrition. There is a multibillion dollar pet food industry in this country determined to get you to feed the “right” food. The implication and sometimes the outright statement by the “oh so friendly clerk” is “Feed this food and your dog will not itch”.  And how did this person draw this conclusion? You have to wonder. Veterinary dermatologists have determined that food allergies represent the lowest number of allergic dogs seen in general practice, comprising only about 10% of allergic dogs. Of those dogs, allergies to “grains” are a small portion. There is currently a huge push on “grain free” diets being touted to solve skin allergy problems. While not harmful, grains fall under the category of “probably unnecessary” for most dogs because dogs are most certainly carnivores.

Allergic Threshold

The body is constantly exposed to environmental allergens such as molds, pollen, dust mites and fleas. Both healthy and allergic dogs will produce antibodies (IgE, IgG, IgM) to combat these foreign proteins. The allergic dog is thought to produce significantly higher levels of IgE (considered the most important antibody in producing allergic signs/symptoms) than the clinically “normal” dog. There is no specific IgE that will produce pruritus (itching). Each dog has its own “threshold” (an allergic dog is often thought to have a lower threshold or tolerance, which makes it more susceptible). This becomes important in treatment. For example, let’s say we have a dog that is a known controlled atopic dog (pollens, molds, house dust mites etc.). For this dog with known atopic allergies, flea control becomes even more important because even though the primary allergy is not to fleas, flea bites could cause enough of a reaction to push the dog past its threshold for itching and then the dog becomes symptomatic for its primary atopic allergy.


When the itchy dog walks into my exam room, I think about the 3 most common allergies. Fleas, atopic disease, and food allergies. I must also think of other causes of itching such as:

Ÿ•   Sarcoptic/Notoedric mange (you know it as scabies)

•Ÿ   Cheyletiellosis (walking dandruff mite)

•Ÿ   Demodicosis (another type of mange)

•Ÿ   Pediculosis (lice)

•Ÿ   Dermatophytosis (ringworm fungus)

•Ÿ   Bacterial hair follicle infection

Ÿ •  Malassezia dermatitis (yeast infections)

In a cat, throw in all of the above plus mosquito bite hypersensitivity and eosinophilic granuloma complex. How is all of that figured out? The dermatologist’s tools are 1) detailed history and physical 2) visual and olfactory clues and 3) laboratory testing. These tests include skin scrapings where we visualize directly under a microscope looking for parasites, tape preps and hair plucks. Other tests are the Wood’s lamp (a black light that illuminates certain fungal infections) and smears of skin for cytology (looking for organisms such as yeast or bacteria) or specific cell types that populate certain itchy skin lesions.

The key to solving dermatological issues is patience and lots of it. Diagnosis can be slow and is often done by process of elimination. No matter what you read on the internet, there is NO blood test that will tell you what food your dog or cat is allergic too. Maybe I should state that differently. There are blood tests that CLAIM to tell you what food the dog or cat is allergic to but they are inaccurate and have poor correlation if any with true food allergies. Food allergies are diagnosed by feeding a special hypoallergenic diet for a period of nine weeks. Inhaled allergies are diagnosed by either intradermal skin testing or by specialized blood tests which test for over 64 different allergens.

Tune in next week when we will talk about something that should be important to every pet owner, whether your pet is dealing with allergies or not. I’m talking about the importance of flea control and what happens when you don’t protect your pets from fleas and other parasites. Not pretty.

Until next week………

The tooth, the whole tooth and nothing but the tooth

The tooth, the whole tooth and nothing but the tooth….about teeth

February 6, 2014

From the desk of Dr. Voorheis

“Whadaya mean I have to brush my pet’s teeth?”  “Are you serious?” “How do I do that?” “Why do I have to do that?” These are questions I hear all the time from clients. These questions are great because it gives me the opportunity to provide answers and educate people about the importance of oral hygiene in our pets. And believe me….it is VERY important.  Things that happen in a pet’s mouth can not only cause poor dental hygiene, but they can also cause residual health issues in the body’s major organs. So let’s talk about teeth!

February is National Veterinary Dental care month. This is a month devoted to highlighting your pet’s dental care. My disclaimer on this subject is while I think it’s a fantastic way to get clients and veterinarians to focus on dental care for their pets, it shouldn’t be a focus for only one month each year. Our pets need dental care year round, much like flea control. But that’s another week in the life of the blog. Let me put it to you this way – are you going to brush your teeth for only one month of the year? Are you going to have your kids brush their teeth for only one month of the year? So why should we focus on our pet’s dental health for only one month every year?  Let’s make dental care an ongoing goal for our pets.

I’m going to give you some fun facts before getting into more depth on teeth and oral care. For starters, mammalian teeth are pretty cool and they are not all the same. The shape of the tooth pretty well allows us to classify the animal’s eating habits such as carnivore, omnivore, herbivore, etc. Teeth are either polyphyodont or diphyodont. Huh? Polyphyodont teeth are continuously replaced like in kangaroos, manatees, and elephants. Diphyodont teeth are teeth that have two sets, i.e, deciduous teeth (baby teeth) and a permanent set of teeth. Some baby teeth are lost before birth (or shortly after) like in rabbits. Dogs and cats lose their deciduous teeth between 4.5 and 5.5 months of age. And the human mammal? We keep our deciduous teeth through childhood and when they fall out, the tooth fairy sticks a quarter under your pillow. Well, that’s what happened in my house back in the day. In veterinary medicine there is a general rule of thumb which is that no two teeth of the same type should be in the mouth at the same time. What does that mean?  There should not be a “baby” canine tooth sitting next to an “adult” canine tooth. Never, ever. This leads to dental disease in a more rapid fashion due to overcrowding of the teeth. Now, more fun facts-Dental Formulas.

A dental formula indicates the numbers of teeth in the mouth. Here is more than you ever wanted to know about teeth: The “I” corresponds to Incisors, the “C” corresponds to Canine teeth, the “P” corresponds to Premolars and the “M” to Molars. The number in the numerator corresponds to upper jaw (maxilla) and the denominator represents the lower jaw (mandible). The number 2 indicates that this formula occurs twice, once on the left side of the mouth and once on the right side of the mouth.

Dog:    2 (I: 3/3,  C: 1/1,  P: 4/4, M: ⅔ ) total number of teeth = 42

Cat:     2 (I:  3/3,  C: 1/1,  P:3/2,  M 1/1) total number of teeth = 30

Ferret:  2 (I 3/3,  C: 1/1,  P: 3/3,  M ½) total number of teeth = 34

Rabbit  2 (I: 2/1,  C: 0/0,  P: 3/2,  M 2-3/3) total number of teeth = 26-28

Opossum 2 (I 5/4, C: 1/1, P: 3/3, M 4/4) total number of teeth = 50

I, for one, am glad to not be cleaning Opossum teeth, they have very full mouths!

So where do we start in trying to determine whether or not our pet needs dental care? A ha! Trick question! They all do. I’ve included pictures in this blog (fancy!) and each picture represents a mouth that needs dental care. The “at home” examination begins with you, specifically with your eyes and your nose. If your dog or cat has bad breath, further investigation is needed. To put it bluntly, breath should not stink. If it does, you need to look at your pet’s mouth. I promise it’s not hard. Simply lift up the lip, one side at a time, and take a look. I’ve included some pictures in this blog to help you identify where your own dog or cat may fit in the grading scheme. Cats have the same stages of dental and oral cavity disease as dogs, plus a couple that are unique to cats (of course). Cat’s teeth are more prone to resorptive lesions which are erosions of enamel and painful. Cats are also prone to lymphocytic-plasmacytic stomatitis which is extremely painful. Keep in mind that a painful mouth, just like in humans, can lead to your dog or cat not eating.

While we’re on the subject of bad breath, allow me to elaborate. Halitosis (bad breath) is not always caused by dental or oral cavity disease. It can be caused by any one of these diseases:

  • metabolic disease (diabetes mellitus, kidney disease)
  • respiratory disease (inflamed nasal passages)
  • gastrointestinal disease (megaesophagus – enlarged esophagus traps food – trapped food smells, stomach or intestinal foreign bodies, cancer)
  • dermatologic disease (skin fold infections in the lip folds), trauma (electric cord injury, caustic agents, open fractures)
  • infectious diseases (bacterial, fungal or viral) of the oral cavity, and masses within the mouth caused by cancer or autoimmune disease.

Bad breath can also be caused by our pets eating malodorous or offensive smelling items. Here is a disgusting dose of reality – some of you (and you know who you are) have “poo eaters” in your house. Yes, dogs who prefer to snack on their own poop. And let’s not forget the dogs who venture into the cat’s litter box. Cat poop is a magnificent delicacy for a dog. Gross but true. For so many reasons, best to keep them out of the litter box and out of their own poop piles.

But let’s get back to oral hygiene.  Often, multiple components of halitosis are acting at the same time. A dog or cat may have periodontal disease and one of the situations mentioned above. It will take a trip to the veterinarian to sort this out and prioritize treatment. Since the subject of this particular blog is on dental care, let’s focus on periodontal disease. Perio what?

Periodontal Disease – How does it happen?

Periodontal disease is the most common dental disease and the major reason for loss of healthy teeth and oral pain. Periodontal disease affects the supporting structures of the tooth, which are the gingiva, alveolar bone (tooth socket bone), periodontal ligament (connective tissue attaching tooth to bone) and cementum which covers tooth roots. These structures make up the “periodontium”. Now, bear with me here: Plaque is the major cause of periodontal disease. Plaque is a soft, cream/light grey amorphous deposit. It consists of bacteria, salivary glycoproteins, extracellular polysaccharides mixed with cells, inorganic substances and water. It adheres to teeth and must be mechanically removed. It begins to calcify about 3 days after it is deposited. Calcified plaque is dental calculus (tartar). With me so far?

As plaque calcifies, and calculus thickens, it begins to extend beneath the gingiva. Harmful bacteria get involved and cause gingival inflammation and pain. The gingival margin and epithelial attachment begins to recede. The epithelial attachment begins to recede beyond the cementoenamel junction and a periodontal pocket forms (now we are beginning to abscess the tooth root). Eventually, alveolar bone and periodontal ligament is destroyed and when 50% of the periodontium is lost, teeth become mobile. The mobility results in pain, and continued infection results in tooth loss. In addition, periodontal disease can result in systemic bacteremia which may have a deleterious effect on organs such as the liver, kidneys and even the heart.

Time for a dental check up!

As veterinarians, we stage teeth and periodontal disease during a dental examination. You can ask your veterinarian what stage (or grade) he or she is giving the teeth. When we, as veterinarians, examine the oral cavity of a cat or dog, we will look for things like obvious masses or foreign bodies in the mouth. We will also look for evidence of gingivitis (gum inflammation), gingival hyperplasia (gum thickening), bleeding gingiva, small fractures of the teeth, dental calculus, receding gingiva, exposed roots and loose teeth. We will look for retained deciduous teeth (baby teeth). Based on what we find, we will rate or grade the condition of the oral cavity with one of the following categories:

Normal – Gingival tissue is coral pink or pigmented. It is firm and resilient. There is a sharp knife like border.


This is a normal mouth – note the pope smiling in the background – he agrees with me.


Stage 1 – Gingivitis – Gingival edema, erythema (redness), and loss of stippling occur (stippling can be best explained as a healthy orange peel texture to the normal gum), bleeding is found with minimal manipulation (probing with a dental instrument), there is no attachment loss. This stage of periodontal disease is completely reversible with performance of a complete dental cleaning and daily maintenance of oral health.

Stage 2 – Early periodontitis – Same as stage one, but minor attachment loss is present. Treatment is the same as stage 1.


This is a late stage 1 early stage 2 mouth. There is some calculi present on the upper canine tooth, and the lateral surface of the fourth premolar tooth. Increased pink color over PM4 indicates some gingival inflammation.  This mouth can be managed with a professional cleaning, and followed up with home care.



The above mouth is a grade 2 mouth moving to grade 3. Even though there is not a lot of calculi present, this dog has more advanced gingival hyperplasia and is a heavy plaque former. Teeth cleaning followed by home care will make a significant impact in the health of this mouth.

Stage 3 – Moderate Periodontal disease – Moderate loss of attachment with the development of moderate to deep pockets (space between tooth and gum when probed). Gingival hyperplasia (thickening) and or recession may be present. Gingival recession will limit pocket depth. Bone loss of 30-50% may be found and only slight tooth mobility is present. Treatment is prophylaxis (cleaning), root planning (cleaning under the gum line) and possible gingival surgery). This stage is manageable but not curable. Following a cleaning, home dental care is a must.

Stage 4 – Severe Periodontal Disease – Severe pocket depth, major gingival recession is present. There is greater than 50% bone loss. Teeth are very mobile. Treatment will involve removal of severely affected teeth, with gingival surgery, possible sliding-flap surgery (which involves sliding gum tissue along to cover fistulas (holes) that communicate into nasal passages. This stage is manageable but not curable. Following a cleaning, home dental care is a must.


This is a grade 4 severe periodontal disease mouth. There is severe pocket depth and major gingival recession. There is greater than 50% bone loss, and there are several mobile teeth. Root planning and gingival surgery will be performed on less involved teeth. Severely mobile teeth with greater than 50% bone loss usually require extraction.

After your cleaning – it’s time for “at home” care

After this photo exhibit, I think I can safely assume that we might be willing to do a little bit of work to ensure oral cavity health for our pets. There are 5 different categories of home dental care to consider. The more of these you can manage, the better off your pet will be. The 5 options are tooth brushing, breath enhancers, diet, hard treats, and gingival exercises.

Tooth Brushing

I must make a confession here. For years, I didn’t recommend it. I thought it impossible or ridiculous. In the pictures above, the late 1 early stage 2 mouth, and the normal mouth are my own dogs. In this blog I will repost pictures of them in six months, as I am committing here to brushing their teeth. I’ve been doing it for a while and they both tolerate it. “So wait a minute Doc, why do their mouths look so good, if you haven’t been brushing their teeth their whole lives?” The answer is below but first let’s talk more about brushing those teeth.

The trick to introducing tooth brushing to dogs is to go slow. Tooth brushing care should begin about one week after a dental cleaning. Remember, the gums may be painful due to the cleaning and/or extractions. Start by rubbing teeth with a piece of gauze dipped in bouillon and wrapped around the index finger. Start with the front teeth and as the dog becomes accustomed to having the teeth rubbed, proceed to rubbing the outside surface of the teeth between tooth and cheek tissue. When the dog is comfortable with this procedure, move to a soft child’s toothbrush or a veterinary designed toothbrush. There are also veterinary designed toothpastes – don’t use human toothpaste – they foam too much, dogs don’t like it and it can upset their stomach if swallowed.

Brushing a cat’s teeth is a different challenge. Good luck to you! Many will not tolerate it. You can start by gently rubbing on the outside of the mouth, from nose to the direction of the back of the mouth. You can then move to raising the lip and massaging gums with a finger, with the following step moving to gum massage with a piece of gauze wrapped around a finger. Some cats will then allow introduction of a toothbrush – definitely not all cats will allow this. Cat dental care is more challenging and many times will simply just have to rely on tooth cleaning diets rather than brushing.

Breath Enhancers

These are over the counter chewable tablets designed to “improve the breath” and therefore the sociability of our pets. Make no mistake – this is a band aid for bad breath, not a cure for the reason behind the bad breath.


There are specific prescription diets designed to clean teeth while the dogs or cats eat. The best option is T/D by Hill’s Science Diet or a maintenance diet called oral care is the next best choice. These diets are designed to clean the teeth while a dog or cat eat. They are manufactured in such a way that the fibers in the kibble all run in one direction, thus scrubbing the tooth as the kibble is crushed from crown to gingiva. These have been around long enough for me to form an opinion of them. They work. Simply put, T/D works better than oral care, but both work to improve the condition of the teeth. They are maintenance diets that can be lifelong diets for dogs and cats.  For over 13 years, oral care diets are the only foods I have fed my dogs. Pure and simple, I have been impressed with their effectiveness.

Hard Treats

Hard treats are good, but mostly only clean the crown of the tooth. Carnivores (cats and dogs) generally gulp their food or give one quick crunch and then gulp it down. Even though the benefit is brief, treats do help by providing abrasion to the supragingival (above the gums) tooth surface.

Gingival Exercises

The goal here is to recreate the natural carnivore oral behavior as it hunts prey, kills it, tears the skin and meat from the carcass and devours it bones and all. However, bone chewing can cause significant gastrointestinal problems in domestic pets. Chewing on bones or other hard objects that are harder than the teeth can also damage and break dog and cat teeth. A pink, purple, gray, or tan tooth is a dying or dead tooth and is a condition caused by chewing on objects harder than the teeth. Bone chewing also causes slab fractures on the cheek side of the largest premolar tooth, and tongue side fractures on the lower canine teeth. Rawhide chew toys, biscuits, synthetic bones, knotted ropes, and other such products provide exercise for the gums and abrasive action to help provide gingival exercises and to remove plaque from the crowns of teeth. It is safest for dogs to chew on items softer than their teeth.

I’ve enjoyed writing about periodontal disease in dogs and cats and I’ve only scratched the surface of what we could talk about with the oral cavity of dogs and cats. I will commit to another blog about other oral cavity diseases and specifically will write something about plasma cell stomatitis in cats. Fascinating stuff!

Your pet’s oral care will certainly take a commitment from you. There is work to be done after the dental cleaning so keep in mind it’s not a one stop shop when it comes to a healthy dog/cat mouth. Fortunately, there is significant reward for the commitment you make – a healthier pet with a healthier oral cavity. I can’t see a downside, can you?

Until next week………

Dr. Voorheis


Pet Health Insurance – Friend or Foe?

Pet Health Insurance – friend or foe?

Pet Health Insurance – here we have another topic where opinions vary widely and debates over pros and cons are in no short supply. You may ask, “Do they really have such a thing?” The answer of course is “Yes.” They actually even have pet life insurance. But for this week, we’ll concentrate on the health insurance topic.

Insurance of any kind is one of those things that you buy and hope you never have to use. Having said that, given our pet’s relatively short life spans in comparison to our own, I think it’s common sense to realize that it’s highly likely our pet’s are going to get ill or have accidents and at some point in their lives require significant medical care. And that care can be expensive.

I suppose I could summarize the entire blog at this point with a statement like “Pet Insurance – Get It”. There you have it – my opinion is out of the ‘proverbial’ bag. But I think we can certainly expand on the “why?” of it all and look at some of the pros and cons.

First let’s talk about what it is. Pet health insurance, much like human health insurance, helps cover the cost of medical expenses for illness or accidents. Some pet insurance plans even offer options to cover routine health and wellness visits to include things like vaccinations, annual exams, spaying/neutering, heartworm testing and medications for an additional cost. However, I think the best use of pet insurance is for the unexpected, catastrophic accident or medical events that are difficult to budget for.

Oh come on Dr. V, what are the odds of something really bad happening? Can’t I wait to purchase the insurance until my pet achieves middle age and then purchase it?” I suppose the answer to that is “Yes you can.” But is that the best choice you can make for your pet? That answer is no. To elaborate, let’s look at who is in the hospital right now. Or more specifically, let’s look at a typical day in the life of WBAH.

.. 4 year old dog, whose owners woke up and thought ”let’s go for a walk on the beach with our dog”. It’s a beautiful Saturday morning in January” They were walking on the beach with their dog on a leash, when a much larger dog, broke away from his handler and attacked….. severe lacerations requiring surgery

.. there’s the cat that swallowed a small cork from a bottle….fit perfectly into the diameter of his small bowel….plugging it up completely… requiring surgery

.. the little dog, who lived happily with a big dog, until there was a disagreement…. again lacerations and muscle damage

. middle age dog, runs out in back yard…. comes back holding up rear leg… ruptured cruciate ligament. Requires surgery

…….Senior dog’s entire back right leg is completely swollen from hip to toes within a period of 24 hours and dog can hardly walk. Dog needs surgery to relieve massive swelling. Leg is shaved to begin surgery and puncture wounds are found with skin already dying. Leg is opened up and it looks like a hand grenade had gone off inside the muscle. This dog was bit by a nasty spider…black widow? In its own back yard!

Each of these clients was faced with unexpected veterinary medical bills. These situations are ideal examples of cases that could benefit from the owners having pet health insurance. The sad part is only one of these clients actually has pet health insurance.

Your next question might be “how does it work?” Pet insurance is similar to human health insurance in that it has premiums, deductibles, co-pays and maximum payouts. Covered California doesn’t exist for our pets, so it does not cover pre-existing conditions. Pet health insurance does have waiting periods that define when coverage starts, usually 30 days for the most part but this can be longer for more serious conditions. It differs from human health insurance in that it is a reimbursement program. This means you pay the vet bill and then you file the claim with the pet insurance company for reimbursement. Most insurance companies do have a fairly quick turn-around time for reimbursement and payments are usually in your hands by the time your credit card bill is due. A great benefit with this type of insurance is that pet insurance companies do not use networks so you are able to visit any licensed veterinarian in the United States.

Selecting an insurance company is an individual choice because each person has different needs based on the pet’s breed, the owner’s geographical location and the owner’s budget. Here are my personal suggestions to consider when shopping for your pet insurance:

  • Make sure the plan has good medical coverage. The most comprehensive plans cover accidents/injuries and illness.
  • Make sure the plan has coverage for cancer and coverage for chronic illness and make sure the coverage for chronic illness/disease has a continual coverage option. Some companies will only cover the chronic illness/disease in the policy year it was diagnosed in, after that you will have to pay for continuing coverage.
  • Check to see if it has coverage for hereditary and congenital diseases? Does it cover diseases that are common to your pet’s breed?
  • Pay close attention to “per incident limits” as well as “annual maximums”. Always buy the policy with the highest “per incident” limit that you can afford.

Accident Only policies are cheaper and as the name implies, only cover accidents. They do not cover medical costs caused by illness. Remember that as a pet ages, the number of accident related injuries decreases in comparison to the number of illness related conditions. I would recommend asking many questions of the insurance company. In particular for the middle aged dog who will be running in the backyard and come in limping with a torn cruciate ligament in his knee. You might think this an accident while your insurance company might consider it a chronic disease due to the breed of your dog.

The pros seem fairly obvious. Pet gets sick or pet gets injured and pet insurance helps you pay for that unexpected expense. One of the hardest things I see on a regular basis is an owner that loves their pet and has to make the decision to euthanize because they don’t have insurance and simply cannot afford to treat the animal. And I will say it again – “Pet Insurance – Get It”. I have no reason to promote one brand of insurance over another and it simply does not matter to me or any of us at WBAH which insurance you choose. We just don’t want to see our clients forced into a decision of euthanasia due to lack of funding. That’s just heartbreaking for everyone involved. We do offer Care Credit, but in this day and age, not everyone will qualify for that financing option. Pet insurance on the other hand is available to everyone, regardless of your credit score.

Are there any cons to consider? Pet health insurance has been available in one form or another for more than 20 years. However it still seems to be a subject that confuses people and even makes some wonder if it’s really worth the cost. How do you compare companies and policies without spending hours on end trolling through every available website? I have an answer! There is a website called Pet Insurance Review that can help you. There is a lot of great information on this site, including a way to compare rates and coverage.

Another resource is a website called Pet Insurance University. It’s written by a veterinarian by the name of Dr. Wilkerson and offers lots of great information as well. Dr. Wilkerson goes into far more detail on his site, in explaining the details of pet health insurance than I can go into here.  It’s well worth a look and a read.

In questioning clients who have pet health insurance for their pets, and who have had to use it, the general satisfaction with it seems fairly high. Like any insurance, I don’t think it is always easy to use and I think policies need to be carefully looked at when purchasing. I’ve heard so many stories from clients about how pet health insurance has saved the day for them. One client, we’ll call her JH, was kind enough to share her story with me as to the value of pet insurance in her situation.

I got insurance for Canela when she was about 9 years old. I had debated if it was worth it and finally decided to get it in case of cancer or other huge illness or injury. I researched the companies and realized some gave 80 or 90% return while others gave very little return.   I was still unsure if it was worth it.  However about six months after I got the insurance a mass was found in Canela’s lungs. Diagnostics alone were over $4,000. I paid a little over $400 of that.  She was diagnosed with cancer and given only a few months to live without treatment. Canela lived another year with cancer.  She actually became a little miracle dog.  The cancer never grew.  In the end it was something else that took her.  I never would have had that last year with her without insurance.  Her medical bills were probably close to $15,000 and I paid probably around $2,000 including premiums, etc.  She was my girl and, like so many pet owners, I loved her dearly.”


With the high cost of medicine, we have long reached the point where medical insurance for our pets should be a strong consideration. It’s food for thought in any case.

Dr. Voorheis

Preparing For The Unexpected – Disasters and your pets

Preparing for the unexpected

January 23, 2014


Last Thursday, as I left my home at 6:30 am to head to work, I turned the corner and looked smack at the distant hillside on fire. I knew it wasn’t likely to affect my home directly (wrong way of prevalent winds and it would have had to jump a freeway to do so). So I continued on to work, and paid attention to what was happening as did most of Southern California that day.   Later that day, this would be called the Colby Fire which burned in some capacity for several days.  On my way in, I began to wonder if my clients know what to do for their pets in an emergency situation like fire and earthquakes. It did get me thinking about how prepared I am or how prepared we all are as a community for the next big disaster. Certainly those who live in the common burn areas of Southern California experience these types of disasters more commonly than those of us who live in the more urban areas. However, we should all be equally prepared. Planning is crucial to surviving a disaster.

 Keep in mind that if you need to evacuate from your home, you should take your pets with you. They will most likely be unable to survive on their own and they count on you for their safety. In the event that you are separated from your pets during an emergency or disaster, being able to reunite with them will depend largely on what you have done prior to the incident taking place. Microchips are your best possible tool in being able to find your lost pet. I can’t stress this enough. Microchip your pets. The technology is there now, so that all major chip manufacturers’ chips are read by each other’s scanners. It used to be that one manufacturer’s chip reader would not read another manufacturer’s chip.  Universal scanners are now the norm. In a major disaster, stray animals will be gathered up and taken to the pound or other temporary shelters. Without an identifying chip, the likelihood of these pets returning to their homes is slim. Literally hundreds if not thousands of dogs and cats were relocated across the country following Hurricane Katrina. They were never returned to their homes of origin causing an immense amount of sadness for pets and owners alike. It bears repeating, “Microchip your pets”.


So, how do we best survive a “natural disaster”?  The first thing on your list in any emergency, disaster or otherwise, should be to remain calm. Slipping into a panic mode will not help anyone, including your pets. You’ll want to keep their stress level down so that things like running from the home and or biting someone to do not take place. Know ahead of time what to do, who to call, where to go and what to take with you. These same principles apply for humans as well. Spending some time preparing for an earthquake or other natural disaster removes some of its power over us.


The two main challenges in Southern California are fire and earthquakes. So let’s take a look at that earthquake kit you’ve got in the garage or back bedroom that you can use is either scenario. You know……. the one that isn’t there but you keep meaning to put together?  Yeah, that one. Your disaster kit should have a 5 to 7 day supply of food and water for each pet in your home. This is in addition to all suggested items that are needed to take care of your non furry family members. If you pet has a required prescription medication, keep an additional supply in the disaster kit. The exception is insulin which must be kept in a refrigerator. Your best bet in an earthquake is to keep the door to the refrigerator closed and hope that the fridge stays cold. Icepacks may help. Having a first aid kit specially stocked for pets is also a great idea. Make sure your pet carriers and/or leashes, harnesses and muzzles are readily accessible as well. There is a great pet survival guide available from FEMA on line that I recommend highly. Just click here:

It’s also a good idea to have all your emergency numbers in one place so that they are easily accessible, like on the refrigerator. Things like the veterinarian’s phone number, the pet poison control phone number, numbers to local animal shelters and the emergency vet’s phone number for after hours issues should all be at your fingertips. You should also know where the emergency vet is located. You won’t want to try and figure that out in the middle of an emergency. While things are calm, do a “drive by” to your local emergency vet’s office. Know how to get there quickly and where to park. This may save precious minutes later.

As discussed above, we should start in our own homes with being organized and prepared for the unexpected. Then, we can move on to our neighbors and community. This is where a website such as can be really helpful. It offers suggestions for a neighborhood contact list, neighborhood meetings, etc. Asking questions like who else in the neighborhood has pets or kids and how you can support one another can prove to be very useful in an emergency.  By involving and getting to know your neighbors (yes even the annoying ones), you will increase your odds of helping your family and pets, and others as well. We will all need to come together in the event of a disaster.


On a bigger scale, Los Angeles County has an Animal Emergency Response Annex, who has put together a manual for disaster relief operations for animals. areaanimalannex.pdf

The county provides emergency shelter for evacuated animals and there are provisions for temporary shelters being set up near where people are evacuated as well. Veterinarians have formed the California Veterinary Medical Reserve Corps (CAVMRC) The CAVMRC is guided by the Disaster Preparedness Committed of the California Veterinary Medical Association. Its mission is to preserve animal wellbeing and protect the public health and welfare by providing emergency medical care and expertise in all phases of disaster preparedness and response. Every veterinarian at Washington Blvd Animal Hospital is a CVMA member and supports the CAVMRC.  In the event of a major disaster, these resources will be taxed, but if you have taken the time to prepare then you will have a better sense of control over the situation and feel much more confident about your ability to care for your family and your animals.


Preparing for a disaster is something that most of us chose to ignore. I think we all live in denial to a certain extent and just try to wish it or will it away. But keeping our heads buried in the proverbial sand does no good at all for anyone, especially our pets. Do you need to be prepared for a disaster tomorrow? Who knows. Disasters don’t exactly give notice of their pending arrival. Even though it can be overwhelming to prepare these disaster kits and get ready for the “big one”, whatever that may be, it’s time to start. At least take some baby steps in the right direction. Maybe a New Year’s resolution? Before you know it, you’ll be ready and stocked up. Heck, you might even be the one that everyone else in the neighborhood looks to in a time of need.  Putting some type of disaster plan together, will make you feel better about the care of the critters in your charge.


Until next week……… 


Dr. Voorheis 

Vaccinations – Who, What, When, Why and How?

January 15, 2014

Vaccinations are a controversial subject these days with both humans and animals. There are certainly many varying opinions as to whether or not to vaccinate and when it should be done. So, this week let’s talk about the Who, What, When, Why and How of it all. I’d like to break this all down so that our valued clients have a clear understanding of why vaccinations are necessary and sometimes not necessary. I would also like to talk about the immune system which works hand in hand with vaccinations as well as offer some relevant information about the origin of vaccinations in order to provide a bigger picture and hopefully a better grasp on the topic as a whole. I promise an interesting read!

Before we get this ball rolling, let me say this. Bringing your pets in for an annual exam is crucial to their health and well being. I cannot stress this point enough. Often the exam is MORE important than the actual vaccinations. With the annual exam, things can be caught early before they turn into serious and expensive problems. With your senior pets, exams should be done every six months. Just like people, good health becomes a bigger challenge with our pets as they age. Sticking with one veterinarian is also key. If you see the same vet year after year, that vet knows your pet and will quickly catch any major differences in body condition or lab work. Again, this is crucial in catching things early and fixing things before they grow into larger issues. Now, on to vaccinations.

I’ll start with this statement:  there is a tremendous amount of information and misinformation that is readily available to anyone who has access to the internet, much like our topic from last week – nutrition. So I think a good place to begin is with a basic understanding of the immune system, how it works and how it does what it does so amazingly well.


How does the immune system work? Suffice it to say that the immune system provides multiple layers of defense for an animal (and for people too) to resist infection. These layers interact with one another in a complex dance that keeps us alive and healthy in a microbial world. Some layers of defense are effective against many different types of invaders while others are very specific in their area of protection. Some act against bacteria, some against viruses, and some against parasitic, fungal, or protozoal invaders.

Think of the animal (or human) body as having layered defense mechanisms against microbial invaders. The big three, would be physical barriers such as skin, innate immunity such as inflammation and adaptive immunity such as antibody production. In general, think of the innate immunity as the rapid response that keeps things at bay until adaptive immunity can develop. Adaptive immunity not only recognizes foreign invaders, but also destroys them and retains memory of the encounter. If the animal encounters the organism again, the adaptive response is quicker and more effective. Adaptive immunity can work in two ways. One is the humoral immune response – think antibodies directed against invaders. The other is the cell mediated response – think invaders have gotten inside of cells and antibodies can’t get to them, so then specialized cells destroy these abnormal or infected cells. Make sense?

I think sometimes we lose touch with the fact we, in our modern society, think we are somehow above or distant from a microbial world. In reality, it’s quite the opposite. A healthy immune system constantly protects us and our pets from disease.  Here is a vivid example: the animal body (warm, moist and full of nutrients) is extremely attractive to microorganisms. The magnitude of this can be seen at the time of death, where, within hours, a body decomposes rapidly as bacteria invade its tissues because the immune system is no longer working. So these invaders are there, always lurking and waiting for the opportunity to wreak havoc.  Are all microbes a threat? No. The world is full of microbes (bacteria, viruses, fungi, protozoa, and worms). Enormous numbers of these colonize the skin and intestines, but don’t seek to invade and normally don’t cause disease.  These are called commensal organisms. Others, are more aggressive and do seek to invade and those are called pathogens. Influenza (the flu) is a pathogen as is canine distemper, HIV, Brucella abortus, rabies and a host of others.

Where did vaccines come from and when did it all start? In the late 1800’s Louis Pasteur (of pasteurization fame) discovered that by using an aged culture of the bacterium to be known as Pasteurella multocida, he could protect chickens against “fowl cholera”. He then worked on anthrax, and discovered growing the anthrax organism at high temperatures rendered it avirulent (it wouldn’t cause disease), but the avirulent organism was protective against the virulent organism when injected in sheep. Vaccination was born. These early scientists did not know why or how the immune system worked; it had been left to others to determine the molecular and cellular basis of antimicrobial immunity. Knowing this has enabled us to use immune mechanisms to develop resistance to infectious diseases, thus creating more vaccine possibilities. And that work is still being done today.  I think this is a good time to get into the who, when and what. 


Ever wonder why we vaccinate at the age we do? Why 8 weeks of age? Why not 4 weeks of age? It’s called passive immunity. Newborn mammals are temporarily protected against infection by transfer of immunoglobulins derived from the mother. How that protection gets to the newborn depends on what kind of mammal you are. In humans and other primates, the placenta is hemochorial which allows certain maternal to transfer directly to the fetus. Dogs and cats have an endotheliochorial placenta, which basically means not a lot of passive transfer takes place in the uterus; 5 to 10% is transferred to the puppy or kitten. The rest is transferred in colostrum, the milk that is produced by the mother in the first couple of days of life. In horses, pigs, and ruminants, no transfer in the uterus takes place at all so colostrum is critical as their newborns are entirely dependent on antibodies transferred through milk. Maternal antibodies absorbed from a puppies intestine, reach maximal levels in serum by 12 to 24 hours after birth and have a half-life of about 9 days (kittens – about 10 days). On average, the level of maternal antibodies to distemper declines to insignificant levels by about 10 to 12 weeks, although this ranges from 6 to 16 weeks. Simply put, we don’t vaccinate puppies or kittens at 4 weeks of age, because passive antibody will block the vaccination. The vaccination will be not be effective. Several years ago, many people in an effort to “protect” their puppies were vaccinating against parvo virus at 4 weeks of age. Sadly, this resulted in no protection, a false sense of security and a waste of money. There is an exception to this rule which is the puppy or kitten that received no colostrum from the mother. These babies can and must be vaccinated “early”. For this colostrum deprived puppy or kitten, they can mount an immune response as young as 2 weeks of age.

The earliest age recommended to vaccinate a puppy or kitten with a reasonable expectation of success is at 8 weeks. Two additional vaccinations are recommended spaced about 4 weeks apart. Simply remembering 8, 12, and 16 weeks is the safest way to vaccinate a puppy or a kitten. This is because, some (and we cannot tell which ones), will be susceptible at 8 weeks of age, so they need to be vaccinated at that age. Some will still have maternal antibodies in sufficient numbers to block that vaccine so their first effective vaccination won’t be until the 12 week injection. All maternal antibodies will be gone by the time the 16 week injection is administered, with the 16 week injection acting to boost the amnestic (memory) response. A booster shot is then given at one year of age. Here are two charts for an easy and quick reference.

Core Vaccines for Dogs

##Dogs Distemper Adenoviru s 2 Parainfluenz a* Parvo Rabies
8 weeks xx xx xx xx  
12 weeks xx xx xx xx  
16 weeks xx xx xx xx xx
1 year xx xx xx xx xx

*Parainfluenza is not considered a core vaccine by many veterinary internal medicine specialists, however it’s inclusion in 4-way,   5-way and 7 way vaccine protocols is standard amongst vaccine pharmaceutical companies.

Core Vaccines for Cats



Panleukopenia or feline parvo virus


Calici virus


Herpes Virus or

































*Chlamydia, is often included by major vaccine manufacturers – in the “4 way vaccine” known as FVRCCP; it is felt by many to be a significant component of the feline upper respiratory disorders. It is not considered “core” by the American Association of Feline Practioneer’s Vaccine Advisory Panel. We include it in our core vaccination.

**Feline Leukemia Vaccination – as of 2013, the AAFP Advisory Panel has moved feline leukemia vaccination into the list of core vaccines. The reasoning – is that at 12 and 16 weeks of age, the ultimate type of home the kitten will be in is often unknown and the risk of Feline Leukemia is too great to overlook. At Washington Blvd Animal Hospital, a discussion of where the cat lives and with who, precedes a decision to vaccinate against FELV. If a decision is made to vaccinate against feline leukemia there must be a negative test for feline leukemia prior to vaccinating.

*** Feline Leukemia Core Vaccination at 1 year – at one year of age it is reasonable to know whether or not the cat is an outdoor cat, or an indoor cat. Or a mix of both. Outdoor cats, and indoor-outdoor cats, OR inside cats who have exposure to cats that are indoor-outdoor should be vaccinated against feline leukemia.

You will notice I didn’t fill out the chart for dogs and cats beyond the first year. In part, that is because I don’t think there should be a table of all possible vaccinations and when they should be administered. In addition, I believe the decision of how often to vaccinate, and against what, is a medical decision not just an automatic one. A discussion of your dog and cat’s vaccination needs should be part of every annual exam. For example, the dog that is frequently boarded and groomed at professional facilities and/or visits doggy day-care or dog parks certainly has different vaccine requirements than the 4 year old house dog that never leaves the house. In addition, while we now know that the core vaccinations have an effective “protective” life of 3 years or greater, many of the non-core vaccinations are only effective for six months (i.e. bordetella). 

The same thought process is true for cats, but with cats, we have the added dimensions of the stress of multiple cat households and lowering of immunity for that reason. Shelter cats, rescue cats, all change how we vaccinate.  The bottom line on vaccinations is that during the annual examination, the decision to vaccinate is brought up and discussed. In general with cats, this same every 3 years vaccination holds true, with the exception of the rabies shot, which is yearly.


Most of us see the requirement for a rabies vaccination, as a pain in the neck. It is seen as more of a government intrusion in our lives.  You might think “we have to pay for a license, we have to get this shot for our animals and we have never even seen a case of rabies”. Yet worldwide, rabies kills more than 50,000 people a year! Most of those cases are caused by being bitten by a rabid dog. The reservoirs for rabies in California are skunks and bats.  Rabid bats are also found every year in Los Angeles County believe it or not. According to the Veterinary Public Health and Rabies Control Program of the Los Angeles County Department of Public Health. Of note, LA County has reported record-setting numbers of rabid bats in the past few years. Usually between 8-12 are found per year, but 30-50 per year have been found in the last few years. These are not limited to mountainous regions. In fact, one was found in downtown Los Angeles not too long ago. You can find maps and more data on their website. Here is their rabid bat map for 2013:  Overall, in North America, the top three mammals affected with rabies (other than the bat) are Raccoons, Skunks and foxes. Coyotes have been found with rabies as well (South Texas).

Vaccination and licensing programs are the key to keeping human rabies cases low in this country. Without a doubt, rabies vaccination programs save lives.

A special section of this blog should be devoted to the subject of feline injection site sarcomas. Vaccine associated sarcomas were first recognized as an issue in cats in the early 1990’s. Initial studies suggested a rate of 2 cases/10,000 and in one study that jumped up to 13-36 cases/10,000 (that’s a huge increase). Finally, current estimates based on very large studies suggest the risk of sarcoma development is actually low, well below 1 per 10,000. BUT, there is a risk. Some cats, who have been vaccinated against feline leukemia or against rabies, developed cancer. The risk is low, but we can lower it even further by vaccinating only those cats at risk. By using the appropriate type of vaccinations and by placing the vaccinations in a location that would allow better management of a cancer should it occur. The flip side of the coin should be examined as well. If you’re an outdoor cat, there is a greater risk of catching the feline leukemia virus and dying from it than there is developing an injection site sarcoma. Feline rabies cases are more common than canine rabies cases, so the need to vaccinate, the need to protect feline and human lives against rabies is real.  So yes, I still recommend vaccinating against feline leukemia for at risk cats. I still recommend vaccinating against rabies in cats as well. In some areas, you are not given the choice because the county requires it. In other areas, it becomes a choice of looking at who is at risk.

Which almost brings me full circle and I would ask your indulgence in a brief discussion of vaccinations in both humans and animals. I have been practicing veterinary medicine long enough (31 years) to have seen animals infected with disease that my younger associates rarely see.  Prior to my entrance into veterinary school in the early and mid 1970’s – I worked at this same hospital as a technician (remember the first blog). I dealt with cages of cats with severe upper respiratory disease that dwarf the upper respiratory diseases we see now.  In the early years of my practice career, cases of canine distemper were frequent. Puppies with severe distemper pneumonia would manage to survive only to die from the neurologic form of the same disease. I remember when “any sick cat” that showed up first had to have feline leukemia ruled out because it was so common. Parvo virus wiped out thousands and thousands of dogs when it first broke out in the late 1970s and early 1980s. It is now primarily a disease of unvaccinated puppies, but the virus is resistant, long lived and is spread by flies. This year I saw my first adult dogs with parvo virus in years. It is my sincere hope that this was just a blip on the radar, but let’s get something straight. Vaccines, in both humans and animals save lives. In veterinary medicine they have been blamed for immune mediated disease, hypothyroidism and other disorders. There is no evidence for this at this time in peer reviewed journals. When a vaccination has been linked to a problem, (as with the feline injection site sarcomas) it has been studied, published and answers and recommendations have come forth. In human medicine, vaccinations have been unfairly linked to epilepsy and to autism. It is natural to confuse subsequence with consequence. Many of the babies that were vaccinated against pertussis that developed seizures and severe neurologic disorders ultimately were found to have a genetic defect in the sodium transport system in their brains. Same goes for autism, there are no credible links of vaccinations causing autism. When we don’t vaccinate our dogs and cats, when we don’t vaccinate our children… we put the “herd” at risk. We risk being revisited by the diseases of my early veterinary career, and we risk being revisited by the diseases of my parents and grandparents generations. To quote another colleague of mine, Kathleen Barry M.D., “Vaccinations are the crowning achievement of the 20th century”. I simply could not agree more. Until next week……………… 

Dr. Voorheis