[Tuberculous epididymitis caused by intravesical BCG therapy: a case report]

We describe a case of tuberculous epididymitis that occurred 35 months after completion of a course of intravesical Bacillus Calmette-Guerin (BCG). A 67-year-old man had received trasuretheral resection for bladder cancer in February 1997. Two weeks after the operation, a course of 8 weekly intravesical instillations of BCG (Tokyo 172 strain) was carried out between March and April, 1997. Under the diagnosis of benign prostatic hypertrophy, transuretheral resection of the prostate was performed in March 1998. Multiple tuberculous nodules were histopathologically detected in resected prostatic tissues. The patient complained of a small nodule in the right epididymal tail in August 2001. The nodule developed during 6 weeks, with spontaneous perforation of the scrotal skin and discharge of pus. The pus contained acid-fast bacilli, which were shown to be tubercle bacilli by polymerase chain reaction (PCR) with pan-mycobacterium primer. MPB64-T2, T6 and pncA-7, 11C were positive, while PT-1, 2 and pncA-7, 10 were negative by PCR. These results revealed that Mycobacterium bovis (BCG Organism) was the cause of the epididymitis. Drug therapy for 3 months with rifampicin, isoniazid and ethambutol was initiated in September 2001, and right orchiectomy was performed in October. Histopathological examination showed tuberculous epididymitis. In this case, persistent BCG organisms may have reached the epididymis from the prostate, and may have been activated by immunosuppression associated with aging. In addition, PCR with species-specific primers was useful in differentiating Mycobacterium bovis from Mycobacterium tuberculosis.