Epstein–Barr virus-associated infectious mononucleosis with acute epididymitis: a case report

Infectious mononucleosis due to the Epstein–Barr virus is an infectious disease that causes the appearance of atypical lymphocytes in the peripheral blood; it mainly presents with fever, tonsillar pharyngitis, and lymphadenopathy. In addition to hepatitis, splenomegaly, and rashes, it can involve different organs. Here, a case of epididymitis as a rare complication in a patient with Epstein–Barr virus-associated infectious mononucleosis was reported.

A healthy 23-year-old man visited an outpatient clinic with fever and pharyngitis. Tonsillar pharyngitis, lymphadenopathy, atypical lymphocytes in the peripheral blood, liver dysfunction, and splenomegaly were observed. The patient was diagnosed with infectious mononucleosis based on clinical signs. The next day, the patient developed left testicular pain and was immediately transferred to the emergency outpatient ward. Pain, redness, and swelling were observed in the left scrotum. Ultrasonography revealed swelling of the epididymis and increased blood flow, and the patient was hospitalized with a diagnosis of left epididymitis. The patient’s symptoms improved with symptomatic treatment and was discharged on day 16 after admission. Changes in antibody titers established a definitive diagnosis of infectious mononucleosis caused by the Epstein–Barr virus. Based on the disease course, the patient was also diagnosed with infectious mononucleosis associated with unilateral epididymitis.

This is the first case report of Epstein–Barr virus-associated infectious mononucleosis complicated with acute epididymitis. Infectious mononucleosis can cause numerous organ-related complications; thus, physicians and healthcare workers should remain cognizant of Epstein–Barr virus-associated complications throughout the body and not just in the primary organs affected by infectious mononucleosis.