Cat pooping on tail

[Merc83]

Hi everyone.

We have a cat named Fluff that we took in about 11 years ago. As long as we've had him, he has had trouble with loose stools. We've taken him to the vet several times about it and they have run blood tests and tests on samples of his poop that we bring in and the vet can't find anything wrong. We've tried some medications that the vet suggested and started giving him pumpkin, but neither clear this up.

Lately though, he started to keep his tail down and curled between his hind legs. When he goes poop, he ends up pooping on his own tail and, because it is loose (almost no form to it at all), it sticks all over it. He then wanders around the house inadvertently wiping it off on floors, furniture etc.

We've taken him to the vet again recently and had him check Fluff's tail, but he said it wasn't broken or damaged. When I wipe off his tail I use paper towel and warm water, but he cries like it hurts him.

Anyone have any idea what the problem might be? Should I go to another vet?