I don't know what else to do.
I have had my cat (2, M) since February 22nd of this year. He was in isolation at his shelter for two weeks after contracting calicivirus at a cat cafe. During isolation, he tore off two of his nails. Clean off. When I went to go get him from the shelter, they told me that "if they noticed this sooner they maybe would have kept him longer" but that I would still be okay to take him home that day. I brought him back so they could trim and clean out his nail beds the next day. I was not aware of this issue until I arrived at the shelter. The vet tech there said "he had never seen nails like this before." His nails are abnormally thick as well.
Unfortunately, the issue has gotten worse. He continues to bite off his nails and they look extremely infected. He does not have a single nail on his body (other than his 4 extra polydactyl ones, funny enough) that look normal. There is a dark buildup around them. Recently, a piece of his nail was biopsied and sent in for a culture. The culture came back positive for MRSA. He now takes Enrofloxacin once daily and the vet recommended a bleach bath. During his first soak in water and a bit of Dawn (as recommended,) one of his nails just fell out. I did not see him chew it out at all. I did not feel comfortable moving to the bleach bath portion knowing that his nail had freshly fallen out.
I can't imagine having chronic infections that affect the paws is healthy nor a comfortable life to live. The thought of having him declawed is also terrible and would make his quality of life bad in a different way. He is the first cat I've ever had and I truly don't know what else to do. This has become so costly and it seems like a very rare issue with no concrete solutions. If you have any experience or advice, please help. Sorry if this is all over the place, I just didn't know where to start and I am very very worried :(