Disseminated Mycobacterium bovis after intravesicular bacillus calmette-Gu rin treatments for bladder cancer.

Transitional-cell carcinoma of the bladder is an aggressive and potentially fatal malignancy. In 1990, the US Food and Drug Administration approved the use of intravesicular bacillus CalmetteGuérin (BCG) for the treatment of superficial bladder cancer.1 BCG is a live, attenuated strain of Mycobacterium bovis (M. bovis) that has been used to treat transitional-cell carcinoma since 1976 and has been reported to eradicate disease in more than 70% of patients with in situ and stage I disease.2 The precise mechanism by which BCG acts is unknown, but a local granulomatous inflammation, centered on a T-cell–mediated immunity response, is thought to play a role.3 While the majority of patients tolerate BCG intravesicular treatments well, a number of adverse reactions (eg, fever, hematuria, dysuria, nausea, and malaise) have been reported.4,5 More serious complications include granulomatous prostatitis, pneumonitis, and hepatitis. We report a case of disseminated BCG infection causing pneumonitis that required corticosteroids and antitubercular therapy for cure.