Orchitis (or-KIE-tis) is an inflammation of one or both testicles. It is usually caused by a bacterial infection or by the mumps virus.
Bacterial orchitis can be caused by sexually transmitted infections (STIs), particularly gonorrhea or chlamydia. Bacterial orchitis often results from epididymitis, an inflammation of the coiled tube (epididymis) at the back of the testicle that stores and carries sperm. In that case, it's called epididymo-orchitis.
Orchitis causes pain and can affect fertility. Medication can treat the causes of bacterial orchitis and can ease some signs and symptoms of viral orchitis. But it may take several weeks for scrotal tenderness to disappear.
Orchitis signs and symptoms usually develop suddenly and may include:
Swelling in one or both testicles
Pain ranging from mild to severe
Tenderness in one or both testicles, which may last for weeks
Nausea and vomiting
The terms "testicle pain" and "groin pain" are sometimes used interchangeably. But groin pain occurs in the fold of skin between the thigh and abdomen — not in the testicle. The causes of groin pain are different from the causes of testicle pain.
When to see a doctor
If you experience pain or swelling in your scrotum, especially if the pain occurs suddenly, see your doctor right away.
A number of conditions can cause testicle pain, and some of the conditions require immediate treatment. One such condition involves twisting of the spermatic cord (testicular torsion), which may cause pain similar to that caused by orchitis. Your doctor can perform tests to determine which condition is causing your pain.
Orchitis can be caused by a bacterial or viral infection. Sometimes a cause of orchitis can't be determined (idiopathic orchitis).
Most often, bacterial orchitis is the result of epididymitis. Epididymitis usually is caused by an infection of the urethra or bladder that spreads to the epididymis.
Often, the cause of the infection is an STI. Other causes of infection may be related to having been born with abnormalities in your urinary tract or having had a catheter or medical instruments inserted into your penis.
Viral orchitis is usually caused by the mumps virus. About one-third of males who contract the mumps after puberty develop orchitis, usually four to seven days after onset of the mumps.
Risk factors for nonsexually transmitted orchitis include:
Not being immunized against mumps
Having recurring urinary tract infections
Having surgery that involves the genitals or urinary tract
Being born with an abnormality in the urinary tract
Sexual behaviors that can lead to STIs put you at risk of sexually transmitted orchitis. Those behaviors include having:
Multiple sexual partners
Sex with a partner who has an STI
Sex without a condom
A personal history of an STI
Complications of orchitis may include:
Testicular atrophy. Orchitis may eventually cause the affected testicle to shrink.
Scrotal abscess. The infected tissue fills with pus.
Repeated epididymitis. Orchitis can lead to recurrent episodes of epididymitis.
Infertility. Occasionally, orchitis may cause infertility or inadequate testosterone production (hypogonadism). But infertility and hypogonadism are less likely if orchitis affects only one testicle.
Infertility. Occasionally, orchitis may cause infertility. But infertility is less likely if orchitis affects only one testicle.
To prevent orchitis:
Get immunized against mumps, the most common cause of viral orchitis
Practice safe sex, to help protect against STIs that can cause bacterial orchitis
You may be referred to a doctor who specializes in urinary issues (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 your symptoms, including any that may seem unrelated to the reason for which you scheduled the appointment.
Give your doctor a history of your childhood illnesses and immunizations. Also, be sure to let your doctor know about any recent illnesses, especially STIs.
Make a list of all medications, vitamins or supplements that you're currently taking.
Write down questions to ask your doctor.
Preparing questions ahead of time will help you make the most of your time with your doctor. List your questions from most important to least important. For orchitis, some basic questions to ask your doctor include:
What's the most likely cause of my symptoms?
Are there any other possible causes?
What kinds of tests do I need? What's involved in those tests?
What treatments are available for orchitis?
How long will it take before I start to feel better?
Will this affect my ability to have children?
Are there any restrictions on sexual activity that I need to follow?
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 may reserve time to go over any points you want to spend more time on. Your doctor may ask:
When did you first begin experiencing symptoms?
How severe are your symptoms?
What treatments have you tried on your own?
What, if anything, seems to improve your symptoms?
What, if anything, appears to worsen your symptoms?
Your doctor is likely to start with a physical exam to check for enlarged lymph nodes in your groin and an enlarged testicle on the affected side. Your doctor may also do a rectal examination to check for prostate enlargement or tenderness.
After that, your doctor may recommend:
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 test. A sample of your urine is analyzed for abnormalities in appearance, concentration or content.
Ultrasound. This imaging test may 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 orchitis.
Nuclear scan of the testicles. A radioactive tracer is inserted into your bloodstream. The scanner then maps blood flow to your testicles, which can indicate torsion or orchitis.