Scrotal tuberculosis is a rare manifestation of extrapulmonary tuberculosis. It includes tuberculous orchitis and epididymitis.
It is rare, and only represents about 3% of the cases of genitourinary tuberculosis 2.
It presents as a painless or slightly painful scrotal mass and so it is hard to differentiate this entity from usual epididymo-orchitis or other conditions as tumors or infarctions 1.
Infection usually affects the epididymis first and then can affect the testis if not treated. It is believed to occur due to a retrograde extension from the prostate and seminal vesicles as well as hematogeneous spread 1.
Scrotal tuberculous begins in the tail of epididymis as it is most vascular and also the vas deferens as it is affected by urinary reflux.
Tuberculous epididymitis: appears as a diffuse heterogeneous predominantly hypoechoic enlarged epididymis or an intrinsic focal nodular hypoechoic lesion. It usually shows increased color flow differentiates this condition from infarction. Bilateral involvement is common rather than non-tuberculous infection
Tuberculosis orchitis: usually preceded or associated with epididymitis. Different sonographic patterns have been described 1:
- diffusely enlarged heterogeneously hypoechoic testis
- diffusely enlarged homogeneously hypoechoic testis
- nodular enlarged heterogeneously hypoechoic testis
- multiple small hypoechoic nodules in the enlarged testis (miliary type)
Other associated findings:
- thickened scrotal skin
- scrotal sinus tract
- scrotal hydrocele
- scrotal abscesses
- intrascrotal extratesticular calcification: at epididymis and tunica vaginalis
- evidence of tuberculosis infection elsewhere
Treatment and prognosis
Antituberculous chemotherapy is the mainstay of treatment. Orchiectomy is rarely required for diagnosis or treatment. It may result in infertility 3.
- bacterial epididymo-orchitis
- primary testicular tumors
- testicular metastasis
- testicular hematoma
- testicular infarction
- heterogeneous enlarged epididymis is more with tuberculous rather than nontuberculous involvement that usually appears homogeneous
- bilaterality is more common with tuberculous etiology
- failure of antibiotic therapy of epididymo-orchitis raise the concern of tuberculous etiology
- the presence of pulmonary or extrapulmonary tuberculosis infection elsewhere often makes scrotal manifestations more likely to be tuberculous
- associated unusual associations of epididymo-orchitis as intrascrotal extratesticular scrotal calcifications, scrotal abscess, and sinus tract are helpful clues
- 1. Malai Muttarak, Wilfred C. G. Peh, Bannakit Lojanapiwat, Benjaporn Chaiwun. Tuberculous Epididymitis and Epididymo-orchitis. (2012) American Journal of Roentgenology. 176 (6): 1459-66. doi:10.2214/ajr.176.6.1761459 - Pubmed
- 2. Das A, Batabyal S, Bhattacharjee S, Sengupta A. A rare case of isolated testicular tuberculosis and review of literature. (2016) Journal of family medicine and primary care. 5 (2): 468-470. doi:10.4103/2249-4863.192334 - Pubmed
- 3. F. M. Drudi, A. Laghi, E. Iannicelli, R. Di Nardo, R. Occhiato, R. Poggi, F. Marchese. Tubercular epididymitis and orchitis: US patterns. (1997) European Radiology. 7 (7): 1076. doi:10.1007/s003300050257 - Pubmed