Hi, Lisa! Glad to hear that Miss Murphy is in good hands today.
Pemphigus is an auto-immune disease in which the immune system goes haywire and interprets skin cells as the enemy and begins attacking them, resulting in crusty type sores (the "crusty" descriptor is considered a tell-tale pemphigus sign). The sores will lead to hair loss in the given spot, and will heal on their own, but new sores will then develop and spread. Willie started with sores on his belly, and honestly, I didn't know for a long time because I just didn't touch his belly that often. Around Thanksgiving, I noticed it, and took him to the vet.... at that point we got our diabetes diagnosis, but at that point, our then-vet's main suspicion was food allergies. As things progressed, Willie's sores spread outward in a straight line up his sides, in a very symmetrical pattern (symmetry is another tell-tale pemphigus sign), and also spread to his legs/paws and to his face and ears. It was heartbreaking. We finally got him to a dermatologist who did a biopsy and diagnosed him immediately.
Most cats with pemphigus will live with it forever, though a small number can achieve remission and go off their medication. The typical treatment is prednisone or prednisolone, but vets have been finding success with cyclosporine, a drug originally developed to prevent organ rejection in transplant recipients. It suppresses the immune system (but not completely) so that it stops attacking the skin cells. We started with 1 pill per day and Willie achieved remission in about a week and a half. After finishing a month of daily doses, we have just started dosing every other day, which we will do for a month. If that works, we'll go a third month every third day, then finally we'll try to wean him altogether. The nice thing about cyclosporine is that it has had zero effect on his BG#s.
The only way to confirm/rule out the diagnosis (along with some other possibilities, including allergies) is a biopsy, which is why I asked about one before. Since starting treatment, it has been like Willie has taken 10 years off his life... healthy shiny coat, bright happy eyes, great BG #s, tons of energy and lots of spontaneous play, which he hasn't done in years.
I hope that explanation helps... and that you get answers soon!! ((hug)) Keeping you and Miss Murphy in my thoughts and prayers!