[Rupture of intrascrotal epidermoid cyst complicated by bacterial infection: a case report].

A 63-year-old male visited our hospital with the chief complaint of right scrotal pain. The right scrotum was swollen to the size of a small egg, and its skin was reddish. The mass was palpable independent of the right testis and epididymis. We diagnosed an intrascrotal abscess. The pus spontaneously issued from the scrotal mass. Sequentially, the abscess was extracted under spinal anesthesia. Membrane-like tissue assumed as the abscess wall was removed. Histologically, the abscess wall was composed of epidermal structure with epidermal keratinization, and horny material was found inside the wall. In the scrotal epidermis overlying the abscess, infiltration of neutrophils, lymphocytes, and multinucleated giant cells were observed. Anaerobic bacteria were detected in the pus of the abscess. Consequently, we diagnosed this case as rupture of an intrascrotal epidermoid cyst complicated by bacterial infection.