What causes swelling and pain in the left testicle?

Swelling and pain in the left testicle may be caused by various factors: 1. Inflammation or infection: Such as orchitis or epididymitis, often accompanied by swelling and pain in the testicle or epididymis, possibly due to bacterial infection. 2. Cysts: Testicular cysts, especially larger ones, may compress nerves in the testicle and cause aching or discomfort. 3. Torsion: In testicular torsion, patients may experience a painful mass around one testicle. Immediate medical evaluation and treatment are necessary to prevent ischemia and necrosis of the testicle. 4. Trauma: A history of injury to the same-side testicle or scrotum, possibly resulting from sports activities or physical play. 5. Other conditions: Varicocele, prostatitis, urinary tract stones, and other diseases may also lead to swelling and pain in the left testicle. When experiencing swelling and pain in the left testicle, it is recommended to seek timely medical attention for proper diagnosis through professional examinations and receive appropriate treatment based on the underlying cause.