I have a 4 year old himalayan cat that is peeing blood. Ihave taken him to two different vets. At first they said it was a bad bladder infection and put him on antibotics. It stopped for two weeks then started again. He was then put on a stronger one. It stopped about two days then started again. They have since done x rays and ultrasounds to see if he has crystals. They came back negative. He been tested for lupus and sugar other blood work done all came back negative. Do you have any ideas.

