Afebrile tuberculous prostatic abscess with rectal fistula after intravesical Bacillus Calmette-Guérin immunotherapy

Introduction: Intravesical Bacillus Calmette-Guérin immunotherapy is generally a safe treatment for non-muscle-invasive bladder cancer but sometimes causes complications.

Case presentation: The patient was an 80-year-old man who had undergone Bacillus Calmette-Guérin immunotherapy for non-muscle-invasive bladder cancer. Two months later, he developed an irregular pelvic mass surrounding the prostate and rectum with no fever. A colonoscopy showed purulent mucus discharge in the lower rectum, and a CT-guided needle biopsy revealed epithelioid granuloma containing Langhans giant cells. Although acid-fast bacteria culture and PCR of biopsy samples were negative, he was clinically diagnosed with Bacillus Calmette-Guérin-related tuberculous prostatic abscess spreading to the rectum. After receiving combined antitubercular drugs for 6 months, his discomfort disappeared with almost complete shrinkage of the prostatic abscess.

Conclusion: Tuberculous prostatic abscess is a rare complication associated with Bacillus Calmette-Guérin immunotherapy and sometimes induces rectal fistula. Conservative treatment with antitubercular drugs is efficient and safe for treatment of tuberculous prostatic abscess.