Gandalf who is my boyfriend's cat lives with me and I take care of him. He didn't want treats one day. This was extremely worrying. He'll claw my hand down when treats are involved! Later, one cat peed on my bed with a clean litter box. Then there was vomit and diarrhea. Gandalf acted strangely as well. He just seemed unhappy. Uninterested in things, inactive. This all happened within 4 days. I had them on an all kibble diet, basically, and decided to switch to all canned food with a small amount of kibble. I decided it was a UTI since everything cleared up after the change in food. I was very scared, but it turned out to be an easy matter.