Arthur has finished with his antibiotics and he's back to having a pink butt hole.
Pink with no swelling, which is such a relief. I will continue to keep an eye on 'things'.
No final diagnosis on what caused it to happen but I trust this vet, completely, and no doubt he's seen it many times before. He did a good exam and there was no belly swelling or pain and I'd seen no blood in the litter box or odd behaviors so he just said to keep an eye on things and if it didn't start to resolve with the antibiotics, or grew worse, to bring him right back in and they'd do an x-ray. He also said sometimes they need a surgical correction to withdraw the tissue. I'm glad that wasn't necessary.
Anyway, I noticed improvement within 2 days and it just continued to get better.
As always, thanks for the emotional support!!
= new reply since forum marked as read
It's always hard when they have some ailment.
It's good that he has healed up.
Those kitties are really lucky to have you as their caring humanslave. 
Anyway, I'm glad that you and your kitties are doing well. 
I'm glad Arthur's is pink and healthy again. 
