Hi italiangirl, and welcome to PT! Unfortunately I don't have any advice for you. The only thing I can think of that comes close is K & L, here on PT, has a kitty called Porch who had similar problems. Unfortunately I don't remember why he had problems, but then he almost died and had to have colon surgery which only aggrivated the problem. This poor kitty who has been through so much has no control over when or where he goes to the bathroom.

I'll see if I can find the thread and give you a link to it.

You're a real sweetheart for taking this poor freezing kitty in and giving him a good home - thanks!