Ureteral Strictures after Intravesical BCG Therapy: Should Antituberculous Treatment Always be Initiated?

Abstract

Objectives: Intravesical Bacillus Calmette–Guérin (BCG) therapy is the standard adjuvant treatment for intermediate- and high-risk non-muscle-invasive bladder cancer. Although generally well tolerated, severe complications may occur, while involvement of the upper urinary tract remains exceptional. We report a rare case of bilateral ureteral strictures following BCG therapy and discuss the diagnostic challenge between active infection and inflammatory reaction. Case Presentation: A 74-year-old woman with a history of pT1 low-grade non-muscle-invasive bladder cancer developed acute renal failure during maintenance intravesical BCG therapy. The delay between initiation of BCG therapy and onset of renal failure was approximately 7 months. Pre-treatment imaging showed no dilatation of the pyelocaliceal systems, and ureteral orifices were consistently patent on surveillance cystoscopy. Subsequent imaging revealed bilateral uretero-hydronephrosis due to distal ureteral strictures associated with inflammatory bladder wall thickening. A comprehensive microbiological workup, including urine cultures and GeneXpert testing, as well as thoracic imaging, was negative. Bladder and peri-meatal biopsies demonstrated chronic fibro-inflammatory changes without evidence of mycobacterial infection. BCG therapy was discontinued, and bilateral double-J stenting with periodic replacement allowed stabilization of renal function at 6 months of follow-up. Discussion: Bilateral ureteral strictures following BCG therapy are extremely rare. The main diagnostic challenge lies in distinguishing active Mycobacterium bovis infection from an immune-mediated inflammatory reaction. In the absence of microbiological and histological evidence of infection, an inflammatory mechanism is more likely. Conclusion: Careful diagnostic evaluation is essential in such cases. When no evidence of active infection is found, conservative management with urinary drainage and discontinuation of BCG therapy may avoid unnecessary antituberculous treatment.