The aim of this study was to briefly review toxic epidermal necrolysis syndrome (TENS) and Steven Johnson Syndrome (SJS), as well as describe the unique complication of ureteral perforation. A case of ureteral perforation in an 18-year old woman with TENS was documented and reviewed. In addition to studying this unusual presentation the authors have also provided a brief review of TENS and SJS along with several common complications of this disease process. The patient in question suffered a severe case of TENS with extensive mucocutaneous involvement. After 2 weeks of intensive therapy, she suddenly became anuric. She developed obstructive uropathy and bilateral hydronephrosis from mucosal debris and sludge. A left forniceal rupture was visualized on pyelography. SJS and TENS are two different presentations in the spectrum of the same disease process. There have been descriptions of gastrointestinal, respiratory, vaginal, and ocular mucosal involvement, including cases of corneal and colonic perforation. However, acute renal failure secondary to ureteral obstruction and perforation has never been described. Although rare, one must entertain every possibility when attempting to diagnose complications of the disease.