excessive accumulation of fluids in the scrotal sac that surrounds the testes (testis) in the male reproductive (reproductive system disease) tract.

There are many forms of hydrocele. The most common is chronic simple hydrocele, in which fluid accumulates gradually about the testes. It usually afflicts men past the age of 40 and is of unknown cause. Hydroceles thought to be a result of other bodily disturbances are called symptomatic. Frequently this type arises as a complication of testicular tumours. A direct blow or other physical injury to the testes may also cause a hydrocele.

Hydrocele typically causes the scrotal sac to swell up much like a bag filled with water. Hydroceles may be painless when small, but, when they reach a sufficient size, their weight pulls on the spermatic cords, which can cause a dull aching pain. Large hydroceles can obstruct urination. Treatment for mild hydroceles simply consists of bed rest and support for the scrotum. More serious cases may require surgical drainage and repair and the administration of antibiotics.