Its unlikely that the bulge was related to kidney stones or inflammation. Perhaps a flank hernia?? I'm not sure what they mean by "inflammation." On a CT scan one can see "stranding" around the kidney or ureter, but this could be the result of a long ago episode. Kidney stones are RARELY a danger to your kidney function, so I wouldn't worry about that as long as they didn't see any blockage on the CT scan.
I went to my GP and he was puzzled because it did not act like a hernia when I coughed or tightened my abdomen and was not in a location that was normal for one. He said the Physicians Assistants was wrong in saying it had anything to do with my Ureter or Kidney. He referred me to a Surgeon a few days later. Both Doctors could not feel an opening in the abdominal wall and upon investigation I disclosed that I slipped and jarred my back two weeks earlier then had a shooting pain in the right side of my back a few days later when I twisted. The Surgeon diagnosed that I had a very rare injury to my spine around T12 and L1 that then pinched a nerve to the muscles at the bulge location. He recommended anti-inflammatory, abdominal exercise, and resting the back to let it heal. I am doing yoga and oblique exercises daily. The bulge has not gotten any larger and no tenderness or pain. The Kidney stone issue had nothing to do with the bulge just a coincidence. I hope this information helps someone else in the future. I am a 59 year old male, 5'11", 240 lbs in excellent health and weight lifts daily (power lifting). Thank you for your time and assistance.