Clinical Pearls & Morning Reports
Published March 28, 2018
A testicular mass due to tuberculosis may be either painful or painless on examination. Read the latest NEJM Case Records of the Massachusetts General Hospital here.
Q: What is the most common testicular tumor in patients older than 60 years of age?
A: The most common cause of testicular tumors in patients older than 60 years of age is primary testicular lymphoma. Overall, primary testicular lymphoma is rare, accounting for only 1 to 2% of non-Hodgkin’s lymphomas and only 1 to 9% of all primary testicular tumors. An accompanying hydrocele is present in approximately 40% of patients.
Q: Does a negative urine culture rule out the possibility of testicular tuberculosis?
A: Patients with renal tuberculosis classically have “sterile pyuria”; an absence of white cells in the urine makes renal tuberculosis unlikely, but a negative urine culture does not rule out the possibility of testicular tuberculosis.
A: Middle-aged men are most commonly affected. In most patients with genitourinary tuberculosis, symptoms typically develop gradually and a scrotal lump is usually present for more than 3 months. Patients often (but not always) present with systemic inflammatory symptoms, such as fever, night sweats, anorexia, and weight loss. Genitourinary tuberculosis typically develops after disseminated disease. More than 50% of patients with genitourinary tuberculosis have renal involvement. Urine cultures and acid-fast staining for mycobacteria can be positive, but the sensitivity of staining is low and cultures can take several weeks to show a positive result. Nucleic acid testing has become a useful clinical diagnostic test for genitourinary tuberculosis because of its more favorable test characteristics and fast turnaround time.
A: In formulating the differential diagnosis of a granulomatous process of the testicle, there are two important considerations. First, the presence of necrotizing granulomatous inflammation most commonly suggests an infectious cause, such as tuberculous or nontuberculous mycobacteria, brucella species, Treponema pallidum, blastomyces species, or other bacteria or fungi. Second, a granulomatous process in a primarily interstitial location is most likely due to infection; on rare occasions, it is due to sarcoidosis of the testicle, which very rarely causes necrosis and is generally a diagnosis of exclusion. In contrast, nonspecific (idiopathic) granulomatous orchitis, which is one of the most common forms of non-neoplastic testicular enlargement, has a predominantly intratubular pattern; in addition, it does not cause necrosis or well-formed granulomas.