I just recently lost a 7-yr-old cat who seemed to come down very ill suddenly. When she was a kitten, she had a chronic problem with prolapsed rectum. She had an operation I believe is called a colopexy and did well for a few years. Her symptoms before she died were increased thirst, discolored urine, not eating on her own, and small dark feces. She quickly went downhill within 24 hrs. This happened during Hurricane Dorian and no vets were open. I tried amoxicillin but she responded just temporarily.