Fungal Infection

Question

Fungal Infection   Dear Dr. Krempels,

I recently had to have put down my 9 year, 3 month old female spayed mini rex house rabbit. She suffered from severe sore hocks which eventually started to bleed even though she never set foot in a wire cage. I attribute the escalation of the hock problem to the baths that I was giving her every three days for a severe fungal infection - this was being done under the care of a veterinarian. I was bathing her with Dermazole shampoo.

I started bathing her at the end of August and continued for three months with no real progress. The fungal infection eventually spread to inside her ears at which time I she was prescribed Hibitane ointment. The veterinarian never tested for the fungal infection but instead it was diagnosed visually. Early in December it was decided to try her on Ketoconazole orally. I stopped giving her this after a week as her appetite waned. I had also stopped the baths because they had become so stressful. Her hair continued to fall out and regrow in spots all over her body. Her tummy was completely without hair.

I know she was an old girl but I am wondering what you would have done? I am sending along a photo of her back area. The infection was also under her chin, behind her ears, on her forehead, tummy and above her tail.

Answer
Dear Michele,

I am sorry about the loss of your beautiful girl.

I think the vet was remiss in diagnosing this as a fungal infection without a biopsy, or at least a culture for fungal dermatophytes.  From the picture, it's very hard to tell what it going on.  It does have some of the earmarks of sebaceous adenitis, which is an autoimmune disorder with no cure and not very many good treatments except keeping it at bay with corticosteroids.  But it's difficult to diagnose, too.  The fact that the condition kept marching over her body despite the treatments makes me suspect that this might have been the culprit.

It doesn't look like mange, but if you were constantly giving her baths, that might interfere with the appearance of mange or fur mite infestation.  Those can be treated with Revolution (selamectin), and that might have been tried.  Might not have helped, but it would at least have eliminated the possiblity that this was due to mites.

It's really pretty simple to diagnose a fungal infection:  if you shine a black light (i.e., ultraviolet light) on the affected areas, they should fluoresce a pale green.  If there is no fluorescence, it is less likely to be a fungal infection.

All this comes too late, I know.  But please do not blame yourself for anything.  You were doing the best you could.  And if it was sebaceous adenitis (which it really does resemble from the photo), then there was little you could do but keep her comfortable as long as possible.

I am sorry for your loss.

Dana