Visiting Vet: Charlotte the Coton de Tulear

Sometimes treatment includes process of elimination.

A fluffy Coton de Tulear.

Charlotte is a Coton de Tulear. What’s that? A breed of dog named for the town of Tulear (now called Toliara) on the island of Madagascar, off the southeastern coast of Africa in the Indian Ocean. How’s that for exotic? Cotons are little dogs, usually weighing around 10 pounds and standing about 10 inches high. Their most distinctive physical feature is an extraordinarily soft, shaggy coat that is usually white. In fact, coton is French for “cotton,” referring to this cottony white fur.

There are many stories about how Madagascar came to be home to this distinctive breed. Some said small white dogs accompanying ladies on long sea voyages or kept by sailors to control rats may have jumped ship when in port. Others told the tale of a vessel that carried a cargo of little white dogs to be sold being shipwrecked near Madagascar. The diminutive pups were said to have swum ashore, roamed in feral packs, then mated with local dogs, eventually evolving into the current breed.

The Coton was a favorite companion to nobles of the native Malagasy and Merina tribes, earning the title “royal dog of Madagascar.” They were valued so highly it was against the law for commoners to own them, thus breeding stock remained tightly controlled and isolated on the island. It wasn’t until the 1960s, when tourism to Madagascar became more common, that the rest of the world discovered these delightful dogs. The American Kennel Club (AKC) officially registered Cotons de Tulear as a breed in 2014.

When Charlotte first arrived at my office in 2008, I honestly had never heard of Cotons de Tulear, the island of Madagascar being pretty far from the Island of Martha’s Vineyard. Charlotte’s owners filled me in a bit, and later I read up on them, to learn about any breed-related problems. Charlotte seemed to fit the AKC description of the Coton as “small but robustly sturdy.” One thing her family did notice, however, was that Charlotte had episodes where she just seemed “off” for a day. She would act mopey, refuse food, maybe eat grass or spit up a bit. Symptoms would resolve quickly, without treatment, usually within 24 hours.

We ran tests, but all were normal. I couldn’t explain her bouts of malaise. Since she was fine in between and wasn’t losing weight or exhibiting any other symptoms, I wasn’t overly concerned. “Maybe it’s related to stress,” I suggested. Cotons are known for their strong attachment to people. Perhaps subtle changes in the household routine upset her. “Or maybe she eats something she shouldn’t now and then,” I speculated. Acknowledging that Charlotte shared bits of whatever the family was eating, and relieved that nothing major seemed amiss, her owners resigned themselves to ride out those occasional “off” days.

Then a year ago, Charlotte started scratching and losing fur. A family friend thought they spotted a flea. I suggested flea control, and prescribed a medication called Apoquel to reduce the itching. Apoquel is the brand name for the veterinary medication oclacitinib, licensed since 2016 to treat itchiness associated with canine allergic dermatitis. Oclacitinib inhibits the enzyme janus kinase 1 (JAK1) that is part of the process involved in clinical manifestations of allergy and inflammation. The medication worked moderately well, reducing Charlotte’s scratching, but it did have a side effect. A positive side effect. The whole time she was taking it, her episodes of malaise and stomach upset disappeared.

Initially I thought this must be a coincidence, especially since potential side effects listed for Apoquel include vomiting, diarrhea, anorexia, and lethargy. I made a note of the owners’ observation, and left it at that. Six months later, they mentioned the issue again. They were trying to pin down anything that might initiate Charlotte’s off days. Being left alone. Loud noises. Sometimes a trip to the groomer, or applying topical flea and tick control products. “Sure sounds stress-induced,” I concluded. Six more months passed. Charlotte had another bout of excessive scratching. I prescribed Apoquel. Her itchiness resolved. And once again, so did her episodes of malaise and loss of appetite.

At this point her family asked if she could take Apoquel indefinitely. “There haven’t been any studies on long-term use,” I replied. “It would be considered off-label usage.” More important, I don’t like medicating without knowing what I am treating and why. Better to find the root of the problem and cure it, rather than simply masking symptoms. I refilled the medication, since it improved Charlotte’s quality of life significantly, and promised to do some further research.

My ensuing discussions with veterinary specialists were enlightening. I learned oclacitinib is in the same drug group as tofacitinib, brand name Xeljanz. Both are JAK inhibitors. Xeljanz is used in people to treat, among other things, inflammatory bowel disease (IBD). The light bulb went off over my head. Of course. Apoquel must be reducing some ongoing inflammation in Charlotte’s gastrointestinal tract. Maybe she had an underlying food allergy or hypersensitivity that made her stomach sensitive, and any stress exacerbated the situation..

Charlotte is now on a trial “elimination diet” for three months, forgoing table scraps and treats and sticking with prescription food. Soon we will wean her off Apoquel and see if her malaise and upset stomach return. If not, then we have a diagnosis of food allergy, which we can control with appropriate diet. If she does not improve with the elimination diet, intestinal biopsy would be the next step for definitive diagnosis. Or we may simply agree on a “presumptive” diagnosis of inflammatory bowel disease and treat accordingly. She can continue Apoquel indefinitely, as long as her owners understand this is off-label usage, and long-term risks have not been studied.

Cotons de Tulear have been described as bright, happy-go-lucky, witty, “naturally clownish and lighthearted” with a “remarkably gentle, sympathetic awareness.” We all want Charlotte to feel well so she can be all of these things every single day.