Epididymitis (ep-ih-did-uh-MY-tis) is an inflammation of the coiled tube (epididymis) at the back of the testicle that stores and carries sperm. Males of any age can get epididymitis.

Epididymitis is most often caused by a bacterial infection, including sexually transmitted infections (STIs), such as gonorrhea or chlamydia. Sometimes, a testicle also becomes inflamed — a condition called epididymo-orchitis.

Signs and symptoms of epididymitis might include:

• A swollen, red or warm scrotum
• Testicle pain and tenderness, usually on one side, that usually comes on gradually
• Painful urination or an urgent or frequent need to urinate
• Discharge from the penis
• Pain or discomfort in the lower abdomen or pelvic area
• Blood in the semen
• Less commonly, fever

Chronic epididymitis

Epididymitis that lasts longer than six weeks or that recurs is considered chronic. Symptoms of chronic epididymitis might come on gradually. Sometimes the cause of chronic epididymitis isn't identified.

When to see a doctor

Never ignore scrotal pain or swelling, which can be caused by a number of conditions. Some of them require immediate treatment to avoid permanent damage.

If scrotal pain is severe, seek emergency treatment. See a doctor if you have discharge from your penis or pain when you urinate.

Causes of epididymitis include:

• STIs. Gonorrhea and chlamydia are the most common causes of epididymitis in young, sexually active men.
• Other infections. Bacteria from a urinary tract or prostate infection might spread from the infected site to the epididymis. Also, viral infections, such as the mumps virus, can result in epididymitis.
• Urine in the epididymis (chemical epididymitis). This condition occurs when urine flows backward into the epididymis, possibly because of heavy lifting or straining.
• Trauma. A groin injury can cause epididymitis.
• Tuberculosis. Rarely, epididymitis can be caused by tuberculosis infection.

Certain sexual behaviors that can lead to STIs put you at risk of sexually transmitted epididymitis, including having:

• Sex with a partner who has an STI
• Sex without a condom
• A history of STIs

Risk factors for nonsexually transmitted epididymitis include:

• History of prostate or urinary tract infections
• History of medical procedures that affect the urinary tract, such as insertion of a urinary catheter or scope into the penis
• An uncircumcised penis or an anatomical abnormality of the urinary tract
• Prostate enlargement, which increases the risk of bladder infections and epididymitis

Complications of epididymitis include:

• Pus-filled infection (abscess) in the scrotum
• Epididymo-orchitis, if the condition spreads from your epididymis to your testicle
• Rarely, reduced fertility

To help protect against STIs that can cause epididymitis practice safer sex.

If you have recurrent urninary tract infections or other risk factors for epididymitis, your doctor might discuss with you other ways of preventing a recurrence.

Your doctor will check for enlarged lymph nodes in your groin and an enlarged testicle on the affected side. Your doctor might also do a rectal examination to check for prostate enlargement or tenderness.

Tests your doctor might recommend include:

• STI screening. A narrow swab is inserted into the end of your penis to obtain a sample of discharge from your urethra. The sample is checked in the laboratory for gonorrhea and chlamydia.
• Urine and blood tests. Samples of your urine and blood are analyzed for abnormalities.
• Ultrasound. This imaging test might be used to rule out testicular torsion. Ultrasound with color Doppler can determine if the blood flow to your testicles is lower than normal — indicating torsion — or higher than normal, which helps confirm the diagnosis of epididymitis.

Antibiotics are needed to treat bacterial epididymitis and epididymo-orchitis. If the cause of the bacterial infection is an STI, your sexual partner also needs treatment. Take the entire course of antibiotics prescribed by your doctor, even if your symptoms clear up sooner, to ensure that the infection is gone.

You should start to feel better within 48 to 72 hours of starting an antibiotic. Resting, supporting the scrotum with an athletic supporter, applying ice packs and taking pain medication can help relieve discomfort.

Your doctor is likely to recommend a follow-up visit to check that the infection has cleared.

Surgery

If an abscess has formed, you might need surgery to drain it. Sometimes, all or part of the epididymis needs to be removed surgically (epididymectomy). Surgery might also be considered if epididymitis is due to underlying physical abnormalities.

Epididymitis usually causes considerable pain. To ease your discomfort:

• Rest in bed
• Lie down so that your scrotum is elevated
• Apply cold packs to your scrotum as tolerated
• Wear an athletic supporter
• Avoid lifting heavy objects
• Avoid sexual intercourse until your infection has cleared

You might be referred to a doctor who specializes in urinary issues (urologist).

What you can do

Make a list of:

• Your symptoms and when they began
• Key medical information, including previous STIs
• All medications, vitamins or supplements you take, including doses
• Questions to ask your doctor

Some questions to ask your doctor include:

• What's the most likely cause of my symptoms? Are there other possible causes?
• What tests do I need?
• What treatments are available?
• How long will it take for me to feel better?
• Should my partner be tested for an STI?
• Should I restrict sexual activity?
• I have other medical problems. How can I best treat them together?

Don't hesitate to ask other questions.

What to expect from your doctor

Your doctor is likely to ask you questions, including:

• How severe are your symptoms? Are they constant or occasional?
• What, if anything, seems to improve or worsen your symptoms?
• Do you have discharge from your penis or blood in your semen?
• Do you have pain when you urinate or a frequent or urgent need to urinate?
• Do you have pain during intercourse or when you ejaculate?
• Have you or your partner had or been tested for an STI?
• Do you do heavy lifting?
• Have you been diagnosed with a prostate condition or urinary tract infection?
• Have you had surgery in or near your urinary tract, or surgery that required the insertion of a catheter?
• Have you had a groin injury?

What you can do in the meantime

While you wait for your appointment, avoid sexual contact that could put your partner at risk of contracting an STI, including sexual intercourse, oral sex and any skin-to-skin contact with your genitals. Let your sex partner or partners know about your signs and symptoms so that they can also seek testing.