Authors Posts by Michelle Gerhard Jasny V.M.D.

Michelle Gerhard Jasny V.M.D.

Michelle Gerhard Jasny V.M.D.
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Michelle Gerhard Jasny, V.M.D. has been practicing veterinary medicine on the Vineyard since 1982 and writing the Visiting Vet column for more than 25 years. She lives and works in West Tisbury.

Mayflower was a six-pound, nine-week-old rescue puppy arriving on the Vineyard from an animal shelter in Tennessee by way of Rhode Island. Her papers said she might be a Boxer cross…or maybe part Chihuahua. Now there’s an interesting mix. “I’ve only had her five days,” her mom reported when she brought May for an introductory checkup. “She’s the cutest little thing, but I just noticed today there’s something wrong with her front leg.” I took a look. Mom was right. Mayflower was pretty darn cute…and her front leg was definitely abnormal. The wrist portion, technically called the carpus, buckled forward, giving her a kind of “double-jointed” appearance. “She doesn’t seem to be in pain,” her owner added, “but it sure looks strange.” “Let’s take a few X-rays,” I suggested.

“Juvenile carpal flexural deformity,” I announced 20 minutes later, after finding no bony abnormalities on the films. “Also called ‘puppy flexor deformity.'” I couldn’t recall seeing a case exactly like May’s before, but my veterinary database was full of pictures of pups with identical, odd-looking forelimbs.

Usually occurring in dogs less than four months of age, this syndrome is actually one of two conditions collectively called “carpal laxity syndrome.” In flexural deformity, the wrists bulge forward. In other words, they are hyperflexed. Conversely, the wrists may be hyperextended, dropping down toward the floor, giving the dogs a sort of bowing appearance. Carpal laxity syndrome is thought to be the result of an inequity between the growth rate of the bones and that of the tendons. Some propose that malnutrition or, conversely, overnutrition, especially in rapidly growing large breed puppies, may weaken muscles and tendons or contribute to irregularity in the tension load, leading to the abnormal positioning. Hyperextension laxity is seen primarily in large breed dogs with some studies suggesting Doberman Pinchers and Shar Peis may be predisposed. Carpal laxity can affect only one front leg or both. It can occur in one leg and then later develop in the other. Occasionally it may resolve and then recur.

Although the funny, wobbly appearance of May’s forelegs might lead one to think they should be splinted, that is not the case. Splinting doesn’t change the course of this syndrome. Hyperflexion usually resolves all on its own in two to four weeks. Hyperextension also typically self-corrects though may take a bit longer, up to several months, depending on the severity.

“Make sure May is being fed a nutritionally adequate diet,” I advised, “but also that she is not being oversupplemented. Keep her on surfaces with good footing,” I continued. “And avoid too much exercise and activities like climbing stairs or jumping out of the car until her legs look normal again.”

Carpal flexural deformities also occur in the young of other species like calves and foals. Now, the closest I’ve gotten to a horse in 20 years is dropping my daughter off at the barn for her riding lessons. (Okay, I tried getting back in the saddle once or twice but ultimately succumbed to my fear of…well, horses. And broken bones.) But I digress. The point is, I’m going to tell you a bit about carpal flexural deformities in newborn foals, often called “contracted tendons,” but I’m no horse doc. If you’ve got a foal with funny forelegs, talk to an equine veterinarian.

Foals with carpal flexural deformity may look like they are standing on tippy-toe, or wearing high-heels. Proposed causes include genetics, malpositioning in the uterus, rapid growth, nutritional deficiencies, or conversely, feeding an excessively nutrient-rich diet. Each case is individual and must be assessed as such. Affected foals may have difficulty nursing due to pain and an inability to stand steadily, making them more prone to aspiration pneumonia, failure to thrive, and infections. In mild cases, if the foal can actually get the bottom of the foot flat down onto the ground, the problem may resolve spontaneously as the weight of her growing body helps stretch the tendons.

Listen carefully to your veterinarian’s advice about any recommended changes in feeding and exercise. Some exercise is good. Too much is bad. A balanced diet is good. Too much or too little of certain nutrients is bad. There is no one-size-fits-all prescription. As long as you see progressive improvement, then no further intervention may be needed.

More serious cases warrant more aggressive treatment. One technique commonly used involves giving the foal oxytetracycline, an antibiotic, administered very slowly intravenously and then applying a temporary splint to the leg. Why an antibiotic? Is there infection in the legs? Nope. Besides its antimicrobial action, oxytetracycline also binds calcium in the system, which temporarily causes muscles to relax. As the muscles loosen, the leg relaxes into a slightly more normal position and a splint can be applied. Your veterinarian will likely want to check your foal’s kidney function before and after this treatment, and give her pain medications and gastric protectants as well. The oxytetracycline may be repeated every other day for a few times and the splints are usually left on for only short periods of time. For foals that do not respond to conservative medical treatment and splints, surgery may be required. Carpal flexural deformity can also occur in mature horses, usually as the result of injury or malnutrition, in which case you should definitely be getting advice from someone besides me.

For little Mayflower, however, I was confident about sending her home with a prescription for “tincture of time.” Her owner very sensibly was content with our “wait-and-see” attitude and the recommendations about diet and activity, while we gave Mother Nature a chance to straighten things out. Three weeks later May’s legs look right as rain…but I still can’t decide if she’s more boxer or Chihuahua.

“What’s up?” I asked casually, ushering Thunderbolt and owner into the exam room.

“This may sound weird,” his mom replied, ” but last night I suddenly noticed one side of his head is all caved in.” By this time Thunder, a sweet ten-year-old Labrador-Beagle mix, was on the table where I could gaze into those big brown eyes. Yup. No doubt about it. Thunder had marked facial asymmetry. The muscles on the right side of his forehead were more pronounced than on the left, where the bony outline of his skull was clearly visible beneath the skin.

“Is he acting sick?” I continued my exam.

“Nope,” she assured me. “He’s feeling fine.” Everything else checked out normally. Thunder’s problem was unilateral, meaning only one side was affected, and symptoms were confined to the head. The first question in asymmetry cases is . . . which side is normal? Sometimes it’s hard to tell. Was the right side swollen? Or the left atrophied? In Thunder’s case the left side was clearly abnormal.

“Probably something wrong with the facial or trigeminal nerve,” I pronounced, rubbing my own forehead. Those pesky cranial nerves. Even 30 years ago in school I would mix them up. “I need to refresh my memory,” I admitted candidly and went off to review cranial nerves as well as inflammatory diseases of the masticatory muscles.

Unilateral facial nerve paralysis is a relatively common condition that often appears to occur spontaneously, especially in cocker spaniels, corgis, boxers, and domestic longhair cats. It can also occur as the result of trauma, middle or inner ear infections, or cancer. Signs on the affected side include drooping lip and ear, inability to fully close the eyelid, and reduced blink reflex. The neurological deficits lead to excessive drooling and difficulty eating normally, with food falling out of the side of the mouth. Chronic cases may develop sideways deviation of the whole face and are prone to eye ulcers and infections.

I stared at Thunder. His eyelid closed normally. I touched the corner. He blinked. His lips were symmetrical. I pinched them. He reacted. I tossed him a liver treat. He scarfed it down neatly. I pulled out my otoscope. Most dogs with deep ear infections will have other symptoms — a head tilt, loss of balance, or pain. Thunder showed none of these but I thought I should check. “Eardrums look fine,” I reported. “This doesn’t look like facial nerve paralysis.” Even if it were, unilateral facial nerve paralysis is usually idiopathic, meaning there is no known cause, nor is there specific treatment. Some dogs recover function spontaneously over time. Others never do, but manage just fine, even with a permanent deficit.

My next consideration was masticatory muscle myositis. MMM is an autoimmune inflammatory condition involving the chewing muscles on the head. Affected muscles are either swollen or atrophied, depending on the stage. Could Thunder have MMM? I reviewed my texts. Ah, that’s right. MMM is almost always bilateral and painful, presenting as an inability to open or close the mouth. Diagnosis involves muscle biopsy or a pricey test looking for those autoantibodies. With early diagnosis, prognosis is good, treating with corticosteroids to suppress the abnormal immune response. But Thunder’s mouth worked perfectly well. I pried it wide open just to be sure. No pain. No problem. No masticatory muscle myositis.

“Okay,” I concluded. “Must be trigeminal neuritis.” Cranial nerve number V, the trigeminal, is also involved with enervating the head muscles. That must be it. This time I searched my online veterinary database. Shoot. Trigeminal neuritis is also usually bilateral and manifested by a sudden inability to close the mouth. Affected animals have a constantly dropped jaw, leading to excessive drooling and messy table manners. No one knows the cause, although an autoimmune etiology is suspected and there is no specific diagnostic test other than ruling out other problems, and waiting. Most dogs recover fully within a month as long as they are given the necessary supportive care to eat and drink throughout that period. As I sifted through discussions of canine facial asymmetry, I stumbled across case after case of middle-aged dogs with the exact same signs as Thunder. Unilateral muscle atrophy of the forehead with no other symptoms. I read a number of cases, then went back to the exam room somberly.

“I think Thunder may have a trigeminal nerve sheath tumor.” I let the news sink in. “That’s cancer affecting the nerve covering. I’ll talk with the specialists and get you details.” The next day I reviewed options with Thunder’s mom. “The oncologist agrees,” I said. Considering Thunder’s age and symptoms, trigeminal nerve sheath tumor was far and away the most likely diagnosis although there was still a slim chance it could be unilateral immune-mediated trigeminal neuritis. “At this point she advises seeing a neurologist. An MRI can confirm the diagnosis and determine the location and extent of the tumor.”

“If it is cancer, what can we do?” his owner asked

Standard treatment is radiation therapy, five days a week for three weeks. A newer option is a “gamma knife” procedure — a much larger dose of radiation targeted at a much tinier area. This process consisting of only one to three treatments but is twice the cost and only performed at a few institutions. “There’s not much data about prognosis with either treatment,” I sighed. “The oncologist said a lot of her patients have done well . . . living one or two years.”

That didn’t sound like a very long time to either Thunder’s mom or me. She needed time to consider the choices. If she wasn’t going to go for radiation treatment, then we could just wait and see. If Thunderbolt improved, it was neuritis. With cancer, we would expect his symptoms to progress eventually. He might have seizures or other neurological abnormalities. It might become painful or prevent normal eating and drinking. But for now, those big brown eyes and wagging tail revealed nothing but a happy, albeit lopsided, dog wondering if he could have another liver treat.

When Snuffy, the 18-year-old cat, arrived with a complaint of chronic nasal discharge, I have to admit I wasn’t thrilled. My own geriatric kitty had this same problem for years and I had never been able to fix it completely. “Eeeuuuuwww,” my kids would shout. “Baby Buck got buggers on me!” I took to leaving boxes of tissues strategically around the house and cultivating an attitude of maternal acceptance of snot. I hoped to do better for Snuffy’s family.

I started by examining Snuffy’s face. Was the discharge from one side or both? Unilateral discharge often indicates a foreign body, tumor, tooth root abscess, or trauma. Bilateral discharge is more typical of infection. Snuffy was dripping from both nostrils. What about the nature of the discharge? Clear or opaque? Any blood?

Several months back, Snuffy had presented with a clear, watery discharge, but now it was a thicker yellowish-green. Holding her head in my hands, I gazed at her. Was her face symmetrical or were there any bulges? Tumors can cause facial distortion, as can certain types of infections. Everything looked even and she was blowing little bubbles from each nostril. That was good. It meant air was flowing on both sides. Tumors often completely obstruct one nasal passage so it is a worrisome sign if an animal is not moving any air through one side. I opened Snuffy’s mouth, looked down her ears, pressed lightly on her eyeballs, checked her temperature. All normal.

“Well, Snuffy has a nasal discharge,” I reported sagely, stalling for time as I collected my thoughts about how best to present our next steps. Full evaluation of persistent nasal discharge in cats requires general anesthesia, skull X-rays, or maybe CT-scan, then rhinoscopy, which means looking up the nose with a teensy-weensy fiberoptic endoscope. Then, if indicated, biopsy, culture, and/or flushing of the passages.

Before doing any of this, a panel of blood tests is advisable to be sure a patient doesn’t have an immuno-suppressive virus such as Feline Leukemia or Feline Immunodeficiency Virus and that there are no serious metabolic or clotting problems. The last thing we want to do is stick an instrument up the nose of a cat with a bleeding disorder and cause massive hemorrhage. The initial tests could be done at my office, but CT-scans and rhinoscopy? That would require referral to a specialist. Would Snuffy’s owners want to pursue definitive diagnosis, considering that she was 18 and her symptoms were not severe? What else could I offer?

Empirical treatment. “Empirical – adj. 1. Relying upon or derived from observation or experiment; 2. Guided by practical experience and not theory, especially in medicine.” Great. My observation was that Snuffy had a stuffy nose. My practical experience suggested her owners should buy stock in Kleenex. I had to do better than that. At the very least, I needed to thoroughly explain the differential diagnosis, treatment options, and prognosis.

One of the most common causes of acute bilateral nasal discharge in cats is upper respiratory tract infection (UTI), especially herpes and calici viruses. Other organisms such as Bordatella, Chlamydia, or Mycoplasma can also be implicated. A sneezing kitten or young cat with a runny nose is a no-brainer. It’s almost always a UTI, which is usually a mild, self-limiting disease. Animals may also exhibit fever, loss of appetite, dehydration, drooling due to oral ulcers, conjunctivitis, and general malaise. Treatment is primarily supportive and most animals recover uneventfully. Many, however, become chronic asymptomatic carriers of the viruses and clinical disease may flair up when an individual is stressed or has other illnesses.

Cats like Snuffy are often referred to as “snufflers.” No one knows for sure what role chronic UTI plays in creating or perpetuating their problems, but most have irreversible damage deep in their nasal passages, with secondary bacterial infection and inflammation. Taking a culture often isn’t helpful because clinically normal cats may have many of these organisms in their nasal passages. Identifying an organism doesn’t mean it’s causing the snotty nose. (One exception is a fungus called cryptococcus. If you find this little bug in a patient’s buggers, you’ve got a diagnosis, but it’s not very common.)

I told Snuffy’s owners that based on her history and presenting signs, the most likely diagnosis by far was chronic rhinitis/sinusitis syndrome, an evasive moniker that describes the problem in an official-sounding way without pinpointing an underlying cause. “If we want to rule out a tumor or fungal infection, we would need to do more testing,” I said. We discussed the situation. If it was a tumor, they felt Snuffy was too old to put her through surgery and possible chemotherapy. I concurred. In time, we would know if it was cancer. The tumor would grow and the clinical presentation would change. Fungal infection seemed unlikely considering her lifestyle. The option of anesthetizing her and flushing her nasal passages seemed unnecessarily risky, expensive, and uncomfortable in light of her age and the mildness of her disease.

Long-term use of antibiotics to control secondary bacterial infection is the usual first line of treatment for snufflers. Other options include anti-inflammatory medications, oral lysine to inhibit herpes virus replication, and saline or antibiotic nasal sprays. We opted to start with oral antibiotics. “If this doesn’t help, we can try some other empirical treatments,” I said, easing Snuffy into her carrier. “But even if she responds, you need to know the odds of a permanent cure are remote.”

Remembering my late Baby Buck fondly, I thought to myself that there are worse things than an old cat with a snotty nose. I hoped the antibiotics would help Snuffy, but I knew her owners loved her dearly and that, once they understood the chronic nature of her condition, they would adjust. Please pass the tissues.