Hydrocele: fluid in the scrotum

What is a hydrocele?

Before birth, as the testicle moves down from the abdomen into the scrotum, it pulls a pouch of the abdominal lining (processus vaginalis) down with it. Normally this channel closes before birth or shortly after. If it doesn’t close, fluid from the abdomen flows around the testicle and the scrotum swells. This is called a hydrocele.

About 5–10% of newborn boys have a hydrocele, and most of these go away on their own in the first 1–2 years.

Types

• Non-communicating (simple) hydrocele: the channel has closed, and fluid has stayed around the testicle. Its size is stable, and it is often absorbed on its own.
• Communicating hydrocele: the channel is open, and fluid moves between the abdomen and scrotum. It is small in the morning and larger in the evening or when the child cries. It can turn into an inguinal hernia.
• Cord cyst: fluid collects above the testicle, along the spermatic cord, as a small cyst.

Signs

• painless swelling on one or both sides of the scrotum,
• the swelling is soft, not tense,
• its size may change during the day,
• when a light is held to it, the scrotum lets the light through.

Diagnosis

The diagnosis is usually made by examination. If the testicle cannot be felt well, the hydrocele is very tense, or it is new in an adolescent, an ultrasound is done to assess the testicle.

Treatment

• In babies, a simple hydrocele is observed until 1–2 years of age.
• Surgery is recommended in these cases: the hydrocele has not gone away after 1–2 years of age, its size changes during the day (communicating), it is very large and tense, or it occurs together with an inguinal hernia.

In children, surgery is done through the groin: the open channel is closed and the fluid is drained. This is different from hydrocele surgery in adults. More: inguinal hernia and hydrocele surgery.

Draining the fluid with a needle is not recommended in children: the fluid builds up again and there is a risk of infection.

Hydrocele in adolescents

A hydrocele that appears for the first time in adolescence can sometimes be a sign of another problem: injury, inflammation, after varicocele surgery, or rarely a testicular tumor. That is why a hydrocele in an adolescent is always checked with ultrasound.