Numbers of shed urothelial cells in urine of patient who had had a urinary catheter for longer than six months with concomitant Provdenca stuarmi chromc urinary tract infection. Freshly collected catheter urine samples were examined before and after bladder lavage with 2t5% (wt/vol) noxythiolin (indicated by arrows). An increase in urothehal exfoliation, with a subsequent decrease, followed each washout.