I know, it's no fun at all is it?
Do you have any other symptoms at this time? From what I understand sometimes mucous or fat can be present in stool and it can be normal. BUT, I also know that when you have UC that every little thing is a worry.
I'd probably go back to enemas every night...and how fast did you taper last time? And have you been fine on every 3rd night before? I think I'm an every other night kind of girl and I don't know if 3rd night will ever work for me. But it's ok, at least I've figured it out. So, is it possible you might need to not taper to every 3rd night ever...or maybe not so quickly?
Just thoughts, hope you feel better!