Epididymo-Orchitis Mimicking Malignancy Resulting From Intravesical Bacillus Calmette-Guerin Immunotherapy for Bladder Cancer: An Attempt to Understand Pathophysiology, Diagnostic Challenges, Patients' Implications and Future Directions.

This case report describes an 85-year-old patient who presented with painless, unilateral right testicular swelling of 2 months' duration. This raised the possibility of testicular cancer, especially given his recent treatment for bladder cancer, which included adjuvant intravesical bacillus Calmette-Guerin (BCG) therapy. This poses a diagnostic dilemma regarding tuberculosis (TB) of the testis, BCG complications or a true testicular malignancy. Biochemical markers and a computed tomography (CT) scan showed no evidence of malignancy or disseminated TB. A TB-ELISpot test was negative. An ultrasound of the testis revealed a hypoechoic soft tissue lesion measuring approximately 24 × 19 mm, with internal vascularity and calcifications, causing a bulge in the testicular capsule with probable extracapsular extension. Based on the clinical suspicion of a testicular tumor, a right inguinal orchidectomy was performed. Histopathologic examination revealed isolated tuberculous orchitis with focal epididymal involvement; the spermatic cord was not involved. Polymerase chain reaction (PCR) testing on the histological sample confirmed the presence of Mycobacterium bovis DNA. As a radical right orchidectomy had been performed, no abnormal tissue remained. Additionally, the CT scan showed no evidence of TB dissemination, and the patient was asymptomatic, so he was being closely monitored in the infectious disease clinic. Importantly, a urine culture became positive for TB, and he was started on antituberculosis medication. BCG-induced granulomatous epididymo-orchitis may rarely occur as a late complication following intravesical BCG therapy for superficial bladder cancer. In this case report, we attempted to understand the pathophysiology, diagnostic challenges, patient implications, and potential future research directions.