“…In travesical formalin (37.8% formaldehyde), used by Brown for the first time in 1969, is an alternative therapy for this devasting complication and has become estab lished as a valuable method [2,5,[7][8][9]22]. However, it has now become evident that serious complications may be encountered and the following have been reported: small contracted bladder, vesicoureteric reflux, ureteric fibrosis, ureterovesical junction obstruction with hydroureteronephrosis, and even death secondary to acute tubular necrosis [6,12,18,20,24], This latter phenom enon may be the direct result of formalin entry into the kidney, due to acquired vesicoureteric reflux. The fre quency and the seriousness of these complications de pend largely on the concentration of the formalin solu tion used [7,8].…”