A rare case of a testicular lesion related to hand, foot, and mouth disease.

Introduction: Hand, foot, and mouth disease generally occurs in children. In rare cases, hand, foot, and mouth disease affects the testicles.

Case Presentation: A 29-year-old man presented to our emergency department with testicular pain for several days after the onset of hand, foot, and mouth disease. Ultrasonography revealed hypoechoic mass-like areas in the right testis. A mild inflammatory response was noted, tumor markers and urinary data were normal, and tests for infection were all negative. Antibiotics were initiated and ultrasonography was performed in every subsequent examination. Testicular pain disappeared 6 months later.

Conclusion: We encountered a rare case of a testicular lesion related to hand, foot, and mouth disease that was successfully treated. The careful selection of treatment for testicular pain and scrotal enlargement in young adult males, such as surgery and symptomatic treatment, based on their medical history and laboratory findings, is important.