Systemic Bacillus Calmette-Guérin (BCG) Infection With Renal Involvement: A Rare Complication of BCG Immunotherapy.

Intravesical instillation of bacillus Calmette-Guérin (BCG) is the adjuvant therapy for superficial urothelial carcinoma of the bladder with the lowest recurrence rates and is well tolerated with minor and self-limiting adverse effects. Serious complications, such as systemic BCG infection, are uncommon as the diagnosis is difficult and, in the majority of cases, Mycobacterium bovis cannot be isolated. We describe a case of a man who presented with prolonged fever associated with polyuria, dysuria, anorexia, and significant weight loss, refractory to several courses of appropriate antibiotic therapy. After an exhaustive investigation, the underlying diagnosis of systemic BCG infection with renal involvement was considered. Antituberculosis treatment resulted in a marked clinical and radiological recovery, supporting this diagnosis.