Get to Know the Causes and Symptoms of a Hydrocele

A hydrocele is a buildup of fluid around a male's testicle. It isn't life-threatening or particularly dangerous, but a hydrocele can cause some discomfort if it gets large.

Who gets hydroceles?

When hydroceles occur in adults, they're typically more uncomfortable than anything else. They occur in about 10 percent of all newborn baby boys and often go away on their own within about the first year of life.

Hydroceles do occur in adolescents and adults, but they are typically associated with newborns. During development in the mother's womb, a boy's testicles form near the kidneys in the abdomen. They develop inside a membrane called the tunica vaginalis, forming a naturally occurring sac filled with fluid that surrounds each testicle.

Often, men who have hydroceles don't ever realize it. It may take an ultrasound exam for an unrelated reason to reveal one.

During the period when gender differentiation occurs, the testicles, still inside the tunica vaginalis membrane, drop down into the scrotum via an opening at the bottom of the pelvis called the inguinal canal.

Typically, the membrane that forms the sac surrounding the testicle closes on its own, and any fluid left inside is absorbed back into the body. When that step doesn't occur or is slower to take place, one of two types of hydroceles develops: communicating or noncommunicating.

Communicating hydrocele

In a communicating hydrocele, the sac surrounding the testicle remains open and connected to the tunica vaginalis in the abdominal cavity above it. This type of hydrocele tends to last longer and may require more intervention to repair.

The fluid surrounding the testicle can pass back and forth to the abdomen inside the tunica, growing larger and smaller at different times of day and depending on the person's activities.

"It might enlarge or decrease in size depending on somebody's position, whether they're lying down and other factors," said Petar Bajic, M.D., a urologist with Cleveland Clinic.

Noncommunicating hydrocele

In this type of hydrocele, the fluid-filled sac around the testicle is closed off, so there's no open channel to the abdomen. The fluid accumulates inside the membrane surrounding the testicle, forming a bubble.

If a noncommunicating hydrocele occurs later in life, it may be linked to another condition, such as an infection, tumor or injury.

"Rarely, a hydrocele is going to be associated with a cancer of the testicle, but that's very rare," Bajic said. "They can also be associated with trauma or injury to the area that leads to inflammation and subsequent fluid collecting around the testicle."

What causes a hydrocele?

Hydroceles are fairly common in newborns, occurring in about 10 percent of infant boys. Since the natural development of the testicles involves them dropping down into the scrotum while they're still surrounded by the tunica vaginalis, the fluid surrounding them may remain longer than usual.

In fact, hydroceles are more common in premature births of baby boys because of this natural pace of development.

Apart from these facts, not much is known about what causes a hydrocele in infant boys, and there's no real way to prevent them, but it should be reiterated: They are relatively common, generally no cause for alarm in babies, are not painful and tend to go away on their own within six to 12 months.

However, when they occur in adults, there may be distinct causes. These include the following:

• Epididymitis. Epididymitis is an infection or irritation that occurs in the epididymis, the tightly-coiled tube attached to the back of each testicle where sperm cells complete their maturation. Sometimes, this inflammation may cause fluid to accumulate and form a hydrocele.
• Infection. Sexually transmitted infections (STIs) and other types of infections may also cause the accumulation of fluid that forms a hydrocele.
• Trauma or injury. A blow to the groin or other injury may cause inflammation, which can cause a hydrocele.
• Orchitis. This is a condition in which the testicle itself becomes inflamed, and it may cause fluid to accumulate in the sac surrounding the testicle.
• Testicular cancer. On rare occasions, testicular cancer may cause a hydrocele.

Hydroceles in adults

Adult hydroceles differ from those that occur in infants in additional ways.

If you don't have a hydrocele when you're born, your chances of developing one later in life are very small. Only about 1 percent of adult men develop one, with the most likely group being men over age 40. Adults are also more likely to get the noncommunicating kind.

"The type of hydrocele that adult men get is almost always a noncommunicating hydrocele," Bajic said. "If that connection with the two spaces remains open, that's a communicating hydrocele. Normally, it's supposed to close, and you're not supposed to have this fluid around the testicles. Later in life, if you have an injury or infection, that space can be easily recreated, and fluid can get trapped."

Often, men who have hydroceles don't ever realize it. It may take an ultrasound exam for an unrelated reason to reveal one.

"The vast majority of hydroceles are not even noticed or bothersome," Bajic said.

Hydroceles in adults generally don't cause issues with fertility or sexual function, according to Cleveland Clinic, but if an adult man has had an undiagnosed communicating hydrocele all his life, it may indicate that the opening where the testicles drop down, called the inguinal canal, is vulnerable to a hernia—a condition in which a loop of the intestine pushes down into the scrotum.

If you have any swelling or discomfort in your testicles, make an appointment to get it evaluated. While hydroceles are often harmless, they aren't the only issues that can cause swelling.

What are the symptoms of hydroceles?

If you do develop a hydrocele, you may notice rare symptoms such as the following:

• Swelling in the scrotum
• Swelling that changes size throughout the day
• A sensation of heaviness in the scrotum
• Discomfort

Conclusions

Hydroceles are fairly common, and they're generally harmless and painless. They often resolve on their own without any intervention at all, especially in infants. Many adult men who develop them never even notice they have one.

However, any swelling in the scrotum should be addressed with a healthcare professional to rule out more serious conditions.