My lexie the black kitty in my siggy had a UTI about two years ago, thankfully because of PT i knew straight away to get her to the vet, she was diagnosed with struvite stones and put on Royal Canin SO, it was a challenge at first to get her to eat them, originally she was put on HILLS, she hated them and became contispated, i dislike Hills myself, Royal canin is supposed to be much more palatable, so far she has been fine, fingers and paws crossed, Irwins problems seem a little different to my lexie, she had no blood at all to be seen,so i am not sure if this would work for Kitty or not, ask your vet,but just wanted you to know i have had success so far, hope kitty gets better soon and stops spraying, sometimes stress or change makes them do that as well. good luck