Do you have a veterinary medical school near you? If so, take her in there for a check up.

Is there a vet near you who treats ONLY cats? (We have 2 in RI). This may also be worth a visit.

You wrote: "she was just so inflamed she couldn't go and had to have a catheter." WHAT is inflamed? Bladder? You need to know specifically. If you don't know, you should be able to find out with a phone call to the vet office. Then include that here.

What are you feeding this cat? Dry kibble? Canned food? Do you always have food out and available, or do you put it down then pick up half an hour later. Please be specific, include brand AND FORMULA.

Doing a Google search, this is the ONLY page I could find which may give you some ideas, either with your current vet, or a specialist cat vet, or a vet at the medical school.
http://healthypets.mercola.com/sites...e-in-pets.aspx

That site means you need to determine the cause more specifically. Is it hormone, birth defect, etc.

I hope this helps! And I'll watch for you to post answers to the questions I posed.