Microbladder due to Granulomatous Cystitis Secondary to BCG Treatment

Intravesical immunotherapy with bacillus Calmette-Guerin (BCG) is considered as the standard treatment for non-muscle invasive bladder cancer with high risk of recurrence and progression.

To report a case of granulomatous cystitis in a patient receiving BCG intravesical therapy for urothelial carcinoma.

A 63-year-old man underwent BCG treatment for a bladder tumor with pathological diagnosis of T1G3 urothelial carcinoma. Five months later, trans urethral resection (TUR) of bladder was performed for an erythematous lesion, with results of post-BCG cystitis. Two years later, the patient presented with hematuria and with suspicious findings in the cystoscopy (extensive fibrin-covered and calcified lesions in the bladder) and a bladder TUR was done.

The histopathological study showed granulomatous cystitis with necrosis and the presence of BAAR compatible with post-BCG origin. In the mycobacterial culture, M. bovis grew, and treatment was initiated. A cystography was performed on suspicion of a microbladder on CT with secondary vesicoureteral reflux, confirmed in this test. It was decided to perform a radical cystectomy. Histopathology reported post-BCG granulomatous cystitis and prostatitis.

After BCG treatment, if symptoms or images are suggestive of granulomatous cystitis, a study of mycobacterial infection should be started to avoid the development of complications, such as the microbladder as in the case we present.