It occurs most commonly as a complication of mumps, but it may also be caused by injury to the testicles or by the spread of infection from elsewhere in the body, such as occurs in epididymitis. One or both testicles may become enlarged and extremely painful. Fever, nausea, and vomiting may also occur. Similar symptoms may occur with testicular torsion, in which the blood supply is blocked to one of the testes.
Immediate surgery is necessary to prevent loss of the involved testicle.
These symptoms may be relieved by the application of ice packs and the use of painkillers. The inflammation usually subsides within a few days.