Our seven year old female kitty is losing fur in a strange way. First, she had small patches missing on her legs - about the size of nickels - on all four legs. After a week or so, the bare spots increased in size... now her legs are almost bare. This started about 3 weeks ago, and I'm noticing that the rest of her coat is starting to show thinning and tiny bare spots as well. The vet has no idea what's causing this. He gave her Proban two weeks ago, thinking maybe ringworm was a possibility. He also put her on an antibiotic for ten days. No improvement! She's eating as usual, no change in diet. Any thoughts?