Itching and Hair Loss in Cats

Skin disease can be a frustrating problem for both cat owners and veterinarians. Itching and subsequent hair loss are just a few of the observed complications from feline skin diseases. Cats can suffer from a number of ailments that lead to the spiral of excessive grooming, scab lesions, raw spots, facial or ears crusts and more.

Allergies to Fleas and Mosquitoes

Cats are excellent groomers and often groom any live fleas or flea “dirt” (flea feces) off of their bodies. It is extremely important to keep cats indoors, implement environmental flea control such as extermination or bug foggers and use a monthly topical flea control product on every dog and cat in the household. Be sure to remove your cat from the premises or keep it away from the chemicals until they are dry and it is safe to return.

“The vast majority of itchy cats that [veterinarians] see are going to be flea-allergic,” said Rudayna Ghubash, DVM, who is board-certified in veterinary dermatology. Many cats are allergic to the flea saliva caused by just one flea bite. Cats with skin disease on their ears, noses and paws can have mosquito bite hypersensitivity.

Parasites

The majority of skin and ear parasites, such as Demodex, Notoedres and Otodectes, most commonly occur in cats less than 12 months of age since kittens have an immature immune system; however, they can occur at any age. Your veterinarian will perform tests including skin scraping and an ear cytology (swab) to check for these mites.

Infection

The fungal infection ringworm or dermatophytosis is the “great mimicker,” as it can imitate any other dermatologic disease. Your veterinarian will pluck hairs from your cat and put them in dermatophyte test medium (DTM) culture (the most accurate test) to see if the fungus will grow. Your veterinarians also may shine a special fluorescent light on your cat’s fur as a screening test known as the Wood lamp examination. Your veterinarian also may perform a skin cytology, taking an impression of your cat’s skin and nails to screen for bacterial or Malassezia (yeast) infection.

Seasonal Allergy and Food Allergy

Atopy (allergy to dust, pollen, weeds, mold, grass, etc.) is very common and usually has a seasonal pattern. There are a variety of treatment options available if your cat has atopic dermatitis. Much less common is the fact that some cats develop an allergy to a food like chicken, beef or fish that they have been eating for several years. Grain-free is not considered hypoallergenic. Dr. Ghubash states that changing your cat’s diet to a “novel” (new) protein/carbohydrate source via a veterinary-therapeutic diet for 12 weeks is the only accurate way to diagnose food allergies. Dr. Ghubash does not recommend an over-the-counter diet for a food trial because food companies use the same equipment to produce different brands of foods.

Autoimmune Disease

Sometimes the cat’s immune system can attack itself, mainly showing red, raw, crusty skin lesions on the ears (a “shake-and-bake” appearance, according to Dr. Ghubash), nails and abdomen. If your cat has a skin problem, talk with your veterinarian about fleas and diagnostic testing (skin scraping, DTM, Woods lamp examination, skin cytology) to get to the root of the problem. To diagnose an autoimmune problem, your veterinarian will take small skin biopsies and send them to a veterinary pathologist to determine the underlying problem. Some of these samples also may be submitted for culture in case some atypical bacteria are involved. The appropriate treatment plan will be formulated based on the results of the pathology and/or culture.

---

Resources:

Ghubash R. The idiosyncrasies of itchy cats. Vetted. July 2016; 34-36.