The vet never told us specifically what could of caused it because she had no way to know. We assumed it was the meat snacks we gave him because that was one of the few variables that made sense to us that the vet listed. Could of even been the food brands we where feeding him at the time, could be the dusty litter.

Regardless we didn't risk any variable and changed to his prescription diet, the litter, and the works and we havent had a issue sense. I still think it was the meat but honestly could of been the liter, or various other things. Certainly not going to start testing to prove my hypothesis.

Also he's 5-6 years old with 4 of those years with us. From those years before the bladder blockage yeah I would say he was a normal healthy cat with no issues before that. Most of the time you don't get a cat with preexisting conditions, you just end up with a cat and you presume its healthy until proven otherwise. He could of had this before but it took a long time for the issue to surface.