I don't know how many people remember this, but I posted previous about it. Since our cats have passed away due to failing health, she's been having accidents inside a couple times a week. I told the vet about this, and he said it could by physical or behavioral. So he put her on baytril twice a day to be safe, and we're going from there. He said if it doesn’t work he recommends taking her one day for a urine sample (since he couldn’t get any from her then) and possible x-rays.
Poor girl, she hates the vet. All we have to do is turn on to that street and she starts whimpering.
The Infamous "Nasty"