[A case report of granulomatous orchitis--review of 20 cases in Japan].

We report a case of granulomatous orchitis. A 31-year-old male complained of right lumbago and scrotal pain. The ultrasonographic finding was multiple hypo-echoic areas in the right testis as highly suggestive of testicular cancer. The diagnosis was made after orchiectomy. Granuromatous orchitis is a rare disease which true etiology remains obscure. Only 20 cases have been reported in Japan. The clinical, radiological and pathological features of 20 cases are presented and discussed. Patients' age ranged from 29 to 79 years, an average of 55 years. The left testis was involved in 7 patients, the right in 9 and 4 cases were bilateral. Ultrasonographic examination of the affected testis revealed hypoechoic mass, so little value in differentiating granulomatous orchitis from neoplasm. The correct diagnosis of granulomatous orchitis has never been made prior to surgery, because it clinically bears a lot of resemblance to testicular cancer. The diagnosis usually is made on histological examination. Orchiectomy is the main form of treatment to date, because antibiotics have little effect on the course of the disease and at the time of diagnosis, the testis is already destroyed and there is hardly any viable testicular tissue in the removed specimens.