Hi, I've been reading this thread for a while and I'm sorry to hear about your cats. I just wanted to mention that when I first adopted Storm he became very itchy and he also started losing the hair on his ears. I was feeding him a lot of cat food that had fish in it. I found out later that he was allergic to fish. Now I actually think that it's the preservative ethoxyquin that he's allergic to. Most fish meals and fish are preserved with this. I've been feeding all of my cats a grain free diet for several years now and yes it does have some fish meal in it but these brands,Innova Evo and Nature's Vareity, don't use ethoxyquin to preserve their fish.

I would take Nikita to the vet to rule out other things like mites and ringworm. I don't know what you're feeding your cats, but a new diet may also be in order. Good luck.