By Mayo Clinic Staff
A hydrocele (HI-droe-seel) is a fluid-filled sac surrounding a testicle that causes swelling in the scrotum. Hydrocele is common in newborns and usually disappears without treatment during the first year of life. Older boys and adult men can develop a hydrocele due to inflammation or injury within the scrotum.
A hydrocele usually isn't painful or harmful and might not need any treatment. However, if you have scrotal swelling, see your doctor to rule out other causes.
Usually, the only indication of a hydrocele is a painless swelling of one or both testicles.
Adult men with a hydrocele might experience discomfort from the heaviness of a swollen scrotum. Pain generally increases with the size of the inflammation. Sometimes, the swollen area might be smaller in the morning and larger later in the day.
When to see a doctor
See your doctor if you or your child experiences scrotal swelling. It's important to rule out other causes of the swelling that might require treatment. For example, a hydrocele might be associated with a weak point in the abdominal wall that allows a loop of intestine to extend into the scrotum (inguinal hernia).
A baby's hydrocele typically disappears on its own. However, if your baby's hydrocele doesn't disappear after a year or if it enlarges, you should ask your child's doctor to examine the hydrocele again.
Get immediate medical treatment if you or your child develops sudden, severe scrotal pain or swelling, especially within several hours of an injury to the scrotum. These signs and symptoms can occur with a number of conditions, including blocked blood flow in a twisted testicle (testicular torsion). Testicular torsion must be treated within hours of the beginning of symptoms to save the testicle.
A hydrocele can develop before birth. Normally, the testicles descend from the developing baby's abdominal cavity into the scrotum. A sac accompanies each testicle, allowing fluid to surround the testicles.
Usually, each sac closes and the fluid is absorbed. However, fluid can remain after the sac closes (noncommunicating hydrocele). The fluid is usually absorbed gradually within the first year of life.
Sometimes, however, the sac remains open (communicating hydrocele). The sac can change size or, if the scrotal sac is compressed, fluid can flow back into the abdomen. Communicating hydroceles are often associated with inguinal hernia.
A hydrocele can develop as a result of injury or inflammation within the scrotum. Inflammation might be caused by an infection in the testicle or in the small, coiled tube at the back of each testicle (epididymitis).
Most hydroceles are present at birth. Between 1 and 2 percent of newborns have a hydrocele. Babies who are born prematurely have a higher risk of having a hydrocele.
In men, hydroceles mostly affect men over the age of 40. Risk factors for developing a hydrocele later in life include:
- Scrotal injury
- Infection, including sexually transmitted infections (STIs)
A hydrocele typically isn't dangerous and usually doesn't affect fertility. However, it might be associated with an underlying testicular condition that can cause serious complications, including:
- Infection or tumor. Either might reduce sperm production or function.
- Inguinal hernia. The loop of intestine trapped in the abdominal wall can lead to life-threatening complications.
If you or your child has painless scrotal swelling, you might be referred to a doctor who specializes in urinary tract and male sexual disorders (urologist).
To get all the information you need from your doctor, it helps to be well-prepared for your appointment. Here's how.
What you can do
- Make a list of any symptoms you or your child has had, and for how long.
- Write down key medical information, including any recent injuries that might have affected the scrotum and any possible sources of infection, including STIs.
- Make a list of all medications, vitamins or supplements that you or your child is currently taking.
- Write down questions to ask your doctor.
For hydrocele, some basic questions to ask your doctor include:
- What do you think is causing this swelling? Are there any other possible causes?
- What kinds of tests are needed?
- What treatment do you recommend, if any?
- What signs or symptoms will indicate that it's time to treat this condition?
- Do you recommend any restrictions on activity?
Don't hesitate to ask other questions that arise during your appointment.
What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them might reserve time to go over any points of concern.
If your child is affected, your doctor might ask:
- When did you first notice this swelling? Has it increased over time?
- Is your child in any pain?
- Does your child have any other symptoms?
If you're affected, your doctor might ask:
- When did you first notice the swelling?
- Have you had any discharge from your penis or blood in your semen?
- Do you have discomfort or pain in the affected area?
- Do you have pain during intercourse or when you ejaculate?
- Do you have a frequent or urgent need to urinate? Does it hurt when you urinate?
- Have you and your partner been tested for STIs?
- Do your hobbies or work involve heavy lifting?
- Have you ever had a urinary tract or prostate infection, or other prostate conditions?
- Have you ever had radiation or surgery in the affected area?
What you can do in the meantime
If you are a sexually active adult, avoid sexual contact that could put your partner at risk of contracting an STI, including sexual intercourse, oral sex and any skin-to-skin genital contact.
Your doctor will start with a physical exam, which will likely include:
- Checking for tenderness in an enlarged scrotum.
- Applying pressure to your abdomen and scrotum to check for inguinal hernia.
- Shining a light through the scrotum (transillumination). If you have a hydrocele, transillumination will indicate the presence of clear fluid surrounding the testicle.
After that, your doctor might recommend:
- Blood and urine tests to help determine if you have an infection, such as epididymitis
- Ultrasound to help rule out hernia, testicular tumor or other causes of scrotal swelling
For baby boys, hydroceles typically disappear on their own within a year. If a hydrocele doesn't disappear after a year or if it continues to enlarge, it might need to be surgically removed.
For adult males, hydroceles often go away on their own within six months. A hydrocele requires treatment only if it gets large enough to cause discomfort or disfigurement. Then it might need to be surgically removed.
The procedure can be performed on an outpatient basis during general or regional anesthesia. An incision is made in the scrotum or lower abdomen to remove the hydrocele. If a hydrocele is found during surgery to repair an inguinal hernia, the surgeon might remove the hydrocele even if it's causing no discomfort.
After hydrocelectomy, you might need a tube to drain fluid and a bulky dressing for a few days. To ease discomfort, your doctor might recommend:
- A scrotal support strap
- Ice packs to help reduce swelling
Your doctor is likely to recommend a follow-up examination because a hydrocele might recur.
Oct. 09, 2014
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