Acute renal failure due to interstitial nephritis after intravesical instillation of BCG.

Intravesical chemotherapy with bacilli Calmette-Guerin (BCG) has been an established therapy for preventing recurrence of, and for treatment of, superficial transitional cell carcinoma of the bladder, but it is not without side effects. A variety of renal complications have been reported and attributed to mycobacterial infection. Although renal complications are uncommon, several cases of interstitial nephritis (with or without granulomas) and mesangial glomerulonephritis have been reported. We report a 76-year-old male patient who developed acute renal failure due to interstitial nephritis after intravesical instillation of BCG. Corticosteroids may serve the recovery of renal function without concomitant use of anti-tubercular therapy, provided systemic signs and mycobacterial infection are absent. Serum creatinine should be checked in at-risk patients in order to detect this complication early.