Expert: Karen Craft - 2/5/2009

Question
I have a 3 year old all black cat. We adopted him another kitten when they were 8 weeks old. (the other cat is fine). This cat had worms when we took him to the vet the first week to get his shots etc. He used to scoot after he popped. After several months of medicines the worms finally went away. As soon as the worms went away he started licking his belly raw. Then he went to his hind paws. Now he is on his tail. His tail and paws have the poodle effect. The vet told us he must be allergic to his food or litter. We learned the first week he was allergic to Tidy Cats litter in the yellow bucket. He sneezes while in the little. Since then we have tried Tidy Cats non-scoopable, Fresh Step clumping and non clumpin, Pine and corn. None of these changes had any effect on his fur growing back. So then we went to food. He doesn't handle Science Diet well - diarhia. We also tried 4 other dry brands from the grocery store. Most caused diarhia. The best so far for his stomack has been Venison & Peas. I tried making him food. (tuna with egg, vitamins, etc). He lost weight but the fur did not grow back. He is about 14 lb but very long. He doesn't look overweight or chubby. He is very active with playing. Sleeps hard. Last month another vet came up with the idea that maybe he was high anxiety since he had no difference with food or litter. For a month we gave him 2 small tablets to help him. The pills did nothing for him. We are out of litter options from all pet stores and grocery stores. We prefer to only use dry food since I am not always home at the same time every day.
He spends an hour or so each day just grooming himself. Every once in a while he will have little scabs from sores on his paws. No sores on his belly or his tail.
Do you have any suggestions or ideas that we could try or present to our vet to think about?

Answer
Hi Debbie,

There is a lot of things that can cause your cat to act like that. Sometimes the simplest answer may be the culprit. Have you treated him for fleas? Even if you do not see them he may have them and they may be the cause of his allergy. Try Frontline or Advantage for cats. See how he is with that.

I am attaching a question and an answer from a vet site that might give you some more insight into what is causing your cat's problem.(In the letter they talk about alopecia. This is just the medical term for hair loss). It sounds like you have pretty much eliminated food allergies. This Q and A will give you some ideas with which you can share with your vet. Hopefully one of them will be the answer you need. But first try the flea medicine. It may be just that. Good luck and let me know what happens.

Ciao, Karen


Question: Hello Dr. Richards,
     We suspect that my cat has psychogenic alopecia and the vet wants him to wear a blue cone for
 a couple of weeks. She ruled out eosinophilic granuloma complex and said that if this doesn't help,
 she will do a biopsy to check for endocrine problems. Larry, my cat, is 12 and has always been
 skittish. Last year his lifelong companion and brother died, and slowly Larry has lost some of his
 skittishness, but is still scared of our children. When school stopped for the summer and the kids
 were home constantly, Larry began losing his fur.
     The cone made him upset and he worked it off within a couple of hours. He could also have a
 flea allergy -- after 12 years of being exposed to fleas seasonally it would be odd to develop like
 this. I read in one of your answers that antihistamines do help the alopecia. I assume they would
 help an allergy. Is this something I should suggest to the vet before she does a biopsy for endocrine
 problems? And what would she be looking for in the endocrine system?
 Thank you, Lauri
 

Answer: Lauri-

It sounds to me like your vet has a good starting plan, to me, except that I hate Elizabethean collars
and try not to use them. They just bother too many pets. This is a very good way to discover if the
hair loss is self inflicted, though. This is helpful information but does not give a definite answer as to
the cause of the problem. It is a reasonable starting point, though.

There are a number of possible causes of alopecia in cats but most of them do show up earlier in life.
Despite this, it probably makes sense to think about all of them and then try to figure out which ones
are unlikely and which ones might possibly be present.

The first question that is usually asked is whether the cat is itchy, or not. It can be very difficult to tell
if itching is present but most of the time, if there is chewing or licking on the fur it is better to assume
that it is.

If itchiness is not present, the most likely diagnoses are a systemic problem leading to hair loss,
endocrine disorders, bacterial skin infections, ringworm and immune system disorders.

In cats, there are some reports of sex hormone related hair loss, hyperadrenocorticism can occur and
some vets believe that there are cases of hypothyroidism in older cats, although this is pretty difficult
to be sure of since it is usually based on response to thyroid hormone supplementation rather than
changes in thyroid hormone levels on lab tests.

If itchiness is present, the most likely diagnoses are skin parasites, bacterial skin infections,
ringworm,  (I know that some things show up in both lists), skin cancers, and immune system
disorders.

It is important to have some information as just a general database to start from when hair loss
occurs in older cats. A general blood chemistry panel and complete blood cell count should be done,
to try to rule out systemic illness such as liver disease contributing to skin disease. A feline leukemia
test should be done, even if this has been done previously, since this is a disease that can lead to hair
loss problems. It may be a good idea to check for feline immunodeficiency virus, as well.  It may be
reasonable to test for the hormonal diseases as well. In cats, a low dose dexamethasone suppression
test may detect hyperadrenocorticism. I am not aware of a good test for the suspected
hypothyroidism that occurs in cats because thyroid values are reported to be in the normal ranges
even in cats that do respond to replacement thyroid therapy. As an alternative, it is reasonable to
biopsy the skin and see if the pathologist detects signs of endocrine related hair loss and then try to
figure out which hormonal skin disease might be present.

Skin scrapings to rule out demodecosis, testing for fungal infections, using good flea control
medications to decrease the possibility that fleas might be present, treating for any bacterial infections
and even considering the use of cortisones to rule out itchiness as a possible contributing factor can
all be helpful.

In Larry's case, I would worry a lot about the possibility of fleas, if you are not using a good flea
control product, such as Frontline (Rx), Advantage (Rx), Revolution (Rx) or Program (Rx). There
might be a change in the number of fleas or they may attack Larry now where they preferred your
other cat in the past. Fleas seem to have preferences for one pet over another sometimes.

These are the things that I can think of that cause hair loss in cats. In sorting through these in a cat of
Larry's age with a previous history that doesn't include hair loss I lean towards doing the general lab
testing first, including at least feline leukemia testing. Then a skin biopsy does make sense, or some
effort to diagnose the endocrine problems through lab work. If nothing can be found it is reasonable
to try some therapies, including antibiotics, corticosteroids or even thyroid hormone supplementation,
although I have personal doubts about that last option.

When everything else has been eliminated then it is time to consider pyschogenic alopecia, unless
somewhere along the line you feel really strongly that this is the most likely problem and decide to try
treating for it prior to doing some of the other testing.

Antihistamines help in cats to control itchiness. They are most successful when hair loss is occurring
due to itchiness from allergies leading to the cat pulling its own fur out. The one advantage of  using
antihistamines early in problems like this is that they can provide relief, if itchiness is the problem,
without causing problems interpreting lab tests and skin biopsy results for hormonal illnesses.

I know that this is a lot to sort through. If this note causes you to have more specific questions,
please feel free to ask them.

Mike Richards, DVM
8/21/2000