Hi Lou
I'm really sorry to hear that
Just something I thought of maybe something or nothing.
I know that HCM is known in Maine Coons is that right??
It has come to light that it is in the Bengal breed too & I have heard that it can effect the kidneys?? I'm no expert at all but do you know if he has been tested for HCM?
Maybe worth a shot & at least you will know if this is the case & medication will help.
Didn't mean to put a damper on an already awful situation but thought it might be of some use. I really hope there is something that can be done