What Is Epididymitis?

Epididymitis is the inflammation of the epididymis, the coiled tube at the back of the testicle that stores and carries sperm. Epididymitis is characterized by pain, redness, and swelling, usually in one testicle only. Bacterial infections are the predominant cause of epididymitis, especially sexually transmitted infections (STIs) like chlamydia and gonorrhea.

Epididymitis is diagnosed based on a review of symptoms along with urine tests, which may include a nucleic acid amplification test (NAAT) and a urine culture to identify the underlying cause. Antibiotics are the mainstay of treatment; the drug selected is based on the bacteria involved.

What Is Epididymitis?

Epididymitis is an inflammatory condition that is typically associated with sexually transmitted infections, although there can be other causes as well. The condition is broken into two subgroups—acute and chronic.

Acute epididymitis is characterized by the rapid onset of symptoms and, by definition, lasts for no more than six weeks. Most cases are related to some sort of infection, often one that is sexually transmitted.

Chronic epididymitis, on the other hand, is characterized by symptoms of discomfort or pain in the scrotum, testicle, or epididymis that persist for more than six weeks. This form is less common and is usually associated with past injury, surgery, or an infection that damaged the epididymis in some way.

The cause of epididymitis is the primary factor driving treatment decisions.

Epididymitis Symptoms

Symptoms of epididymitis can vary by whether the condition is acute or chronic. Generally speaking, acute epididymitis pain tends to be sharp while chronic epididymitis causes dull or throbbing pain.

Common Symptoms

Men with acute and chronic epididymitis may experience some or all of the following signs and symptoms:

• Pain and pressure in the testicle (usually one)
• Redness, warmth, and swelling of the scrotum
• Pain during urination
• The need to urinate often
• Pain during sexual intercourse or ejaculation
• Blood in semen

Acute Epididymitis

Acute epididymitis tends to develop over several days with the pain, redness, swelling, and warmth typically limited to one testicle. The scrotum of the affected testicle will often hang lower.

The epididymis itself will feel significantly thicker and firm. There may be a visible discharge from the opening of the penis (urethra) and pain or burning when urinating.

Chronic Epididymitis

Chronic epididymitis may manifest with persistent tenderness and discomfort, although the actual swelling of the epididymis can come and go. The pain will often radiate to the groin, thigh, and lower back. Sitting for prolonged periods can make it worse.

The persistent inflammation associated with chronic epididymitis can "spill over" to the prostate, leading to discomfort in the groin and perineum (the area between the scrotum and anus) as well as difficulty urinating.

Complications

If left untreated, acute epididymitis can lead to major complications, including the development of testicular abscesses and necrosis (tissue death). Chronic epididymitis may cause permanent obstruction of the epididymis, leading to reduced fertility and hypogonadism (low testosterone levels).

Causes

Though epididymitis is commonly associated with bacterial infections, there are other causes as well. There can also be no identified cause, as is true of most non-infectious cases.

Epididymitis can occur at any age. In adult men, 43% of cases are in those ages 20 to 30. The most common cause varies by age group.

For example, while STIs are usually to blame in cases involving men in their 20s and 30s, urine backflow is a more common cause in older adults.

Infectious Causes

Though urinary tract infections (UTIs) are rare in men, bacterial infections are the most common cause of acute epididymitis. These include:

• Sexually transmitted bacterial infections like chlamydia (Chlamydia trachomatis) and gonorrhea (Neisseria gonorrhoeae)
• Escherichia coli (E. coli), a bacteria that can invade the urethra through fecal contamination or anal sex

Other less common infectious causes include:

• Complications of tuberculosis (TB)
• Viral infections like enterovirus, adenovirus, and influenza in younger boys
• Opportunistic infections like ureaplasma, mycobacterium, cytomegalovirus, or Cryptococcus in men with HIV

Some men with chronic epididymitis will have had a previous acute infection that has damaged the epididymis. In some cases, the injury may affect blood vessels or nerves that service the epididymis, making it vulnerable to bouts of inflammation during illness, extreme physical activity, or other possible triggers.

Non-Infectious Causes

There are also non-infectious causes of epididymitis. These include:

• Benign prostatic hypertrophy (an enlarged prostate)
• Genitourinary surgery (including vasectomy)
• Injury/trauma
• Urinary reflux (the backflow of urine)
• Urinary catheters
• Cordarone (amiodarone), a drug used to treat heart rhythm disorders that is also available as Pacerone
• Autoimmune disease, such as sarcoidosis or Behçet syndrome

Diagnosis

Epididymitis can be diagnosed with a review of symptoms and medical history. The physical exam would look for signs of redness, swelling, tenderness, and warmth occurring unilaterally (on one side only).

The doctor may also check for signs of discharge, often revealed by gently milking the penis with gloved hands. If chlamydia or gonorrhea is suspected, the doctor will take a swab of the discharge and send it to the lab for evaluation. A urine test may be ordered to identify other causes.

If the cause of the epididymitis is unclear or the symptoms are unusual, the doctor may order a Doppler ultrasound to visualize the epididymis and evaluate blood flow to the affected area.

Differential Diagnoses

Conditions that mimic epididymitis include inguinal hernia, infected hydroceles, and testicular cancer and so in order to be certain about the diagnosis and the most effective treatment, a doctor may want to exclude these and other possible causes.

To differentiate epididymitis from testicular torsion, the doctor may test the cremasteric reflex (in which the testicle rises when the inner thigh is stroked). A positive cremasteric reflex generally excludes testicular torsion as a cause. There would also be a positive Prehn sign, in which pain persists even when the scrotum is lifted.

A Doppler ultrasound is the most effective way to differentiate epididymitis from an inguinal hernia, hydroceles, and testicular cancer.

Treatment

In 2021, the U.S. Centers for Disease Control and Prevention published treatment guidelines for sexually transmitted infections—including epididymitis. The prompt treatment of epididymitis is essential to resolving the underlying infection, avoiding testicular damage, and preventing the transmission of a sexually transmitted disease.

The recommended treatment for acute epididymitis depends on the likely cause and whether or not the patient is the inserting partner:

• Chlamydia or gonorrhea: Ceftriaxone 500 mg in a single dose plus doxycycline 100 mg orally two times/day for 10 days
• Chlamydia, gonorrhea, or enteric organisms (men who practice insertive anal sex): Ceftriaxone 500 mg in a single dose plus levofloxacin 500 mg orally once daily for 10 days
• Enteric organisms only: Levofloxacin 500 mg orally once daily for 10 days

If you're prescribed an antibiotic for acute epididymitis you should begin to feel relief within 48 to 72 hours. Relief from chronic epididymitis will likely take longer.

Coping

Whether you have acute or chronic epididymitis, there are several simple things you can do to alleviate the discomfort of pain:

• Rest with your feet elevated to take pressure off the scrotum.
• Wear loose-fitting, non-constrictive underwear and pants or shorts.
• Wear an athletic supporter to support the scrotum.
• Avoid lifting heavy objects.
• Take warms baths to increase blood flow to the scrotum, which will ease discomfort and aid healing.
• Apply ice packs to reduce acute swelling, using a towel barrier and icing for no more than 15 minutes to prevent frostbite.
• Take an over-the-counter analgesic like Tylenol (acetaminophen) or a nonsteroidal anti-inflammatory drug like Advil (ibuprofen) or Aleve (naproxen).

A Word From Verywell

If you develop epididymitis as a result of a sexually transmitted infection such as gonorrhea or chlamydia, it is important to inform your sexual partners so they can seek treatment. If you have had sexual contact within 60 days of the appearance of symptoms, then you are likely to have passed the infection to others. To avoid further transmission, avoid having sex until the infection is confirmed cured.