Povidone-iodine bladder injury in rats and protection with heparin

Povidone-iodine (Betadine) has been proposed for clinical use in controlling bacterial infections by intravesical instillation in concentrations ranging from 0.1 to 1 per cent. The effects, however, of povidone-iodine on the urothelium of the bladder have not been well studied. We performed experiments to see if injury to the urothelium occurred from intravesical instillation in female rats. Injury was indeed found with concentrations of 0.3 per cent and 1 per cent povidone-iodine, as judged by the observations of increased bladder weight due to edema, histological examination, in vivo bladder staining, crystal adhesion and bacterial adhesion upon the bladder mucosa after povidone-iodine injury. Further study showed that the urothelium recovered in 6 to 7 days after povidone-iodine injury, while a 3rd experiment demonstrated at least partial protection from bacterial and crystal adhesion to povidone-iodine injured urothelium by immediate treatment with heparin instillation in the bladder.