Orchitis is inflammation of the testes (Pic. 1). It usually presents with scrotal swelling, pain and redness. Orchitis causes often irreversible damage to the testes and may lead to testicular atrophy (shrinking of the testes), and in rare cases may cause infertility.

Orchitis may be of infectious or non-infectious origin. 

Infectious orchitis

Infectious orchitis may be either isolated (affecting only the testicle) which is more typical for viral orchitis (such as the mumps orchitis), or may be directly related to an inflammation of the epididymis (the tube connecting the testicle to the vas deferens, Pic. 2), called epididymoorchitis, which is commonly of bacterial origin. The most common causative agents of orchitis vary with age. 

In adolescent boys, orchitis caused by mumps infection (Pic. 3) used to be common. 15 – 40% of infected males developed painful testicular swelling, usually within 10 days after the salivary glands swelling. In the majority of cases, the inflammation is one-sided, but affects both testicles in 15-30% of cases. Decreased fertility is an uncommon consequence of testicular inflammation from mumps and infertility is rare. In countries where vaccination against the mumps virus is routinely performed, mumps are nowadays significantly less common.

Epididymoorchitis, inflammation of the epidydimis and the testes, is typically caused by a bacterial infection. Men younger than 35 are more commonly infected with sexually acquired organisms, including Chlamydia trachomatis or Neisseria gonorrhoeae. Men over 35 typically demonstrate infection with enteric Gram-negative rods (rod-shaped bacteria). Gram-negative bacteria commonly cause urinary tract infections, which can spread to the epididymis and testes and cause epididymoorchitis.

Non-infectious orchitis

Non-infectious orchitis can arise as a complication of open inguinal hernia repair. This procedure is widely used for treatment of hernia. The inflammation of testes is then due to compromised blood flow in the testes (ischemia), and is therefore also called ischemic orchitis. Ischemic orchitis typically presents 2–3 days after inguinal hernia surgery and can progress to infarction (tissue death due to ischemia). Ischemic injury is likely due to thrombosis of the venous plexus, rather than injury to the arteries, or inappropriate closure of the inguinal canal. Although ischemic orchitis, atrophy, and subsequent orchiectomy (surgical removal of non-viable teste) are uncommon complications, all patients should be warned of these potential complications and operative consent should include these risks irrespective of the type of hernia or the surgical approach.

Other types of orchitis, such as autoimmune orchitis or tuberculous orchitis, are relatively rare.

The treatment of orchitis depends on the cause. Mumps orchitis usually resolves spontaneously without specific treatment, although medications may be used to alleviate the pain and decrease fever.
In bacterial orchitis, targeted antibiotic therapy is crucial for the outcome. If the inflammation is not manageable by antibiotic therapy or is severely advanced, then an orchiectomy has to be performed.


The main symptoms of orchitis are scrotal pain, swelling and tenderness. Hematospermia (blood in the semen) or hematuria (blood in the urine) may also be present. The patient may also experience symptoms of the causative infection. 

In case of mumps, the infection starts with fever, cough, malaise, chills, nausea or headaches, and subsequently the swelling of the parotid glands develops. 

Patients with epididymoorchitis may present with lower abdominal pain and other symptoms of lower urinary tract infection, such as dysuria (difficult or painful urination), frequent urination, burning sensation during urination, or hematuria. Epididymoorchitis is also usually accompanied by fever and chills. If the patient has a sexually-transmitted disease that caused the orchitis, such as gonorrhea, urethral discharge is a typical symptom as well.

Associated diseases


Mumps is a viral infection caused by the mumps virus, a typically causes inflammation of the salivary glands, pancreas, and testicles; fever, and headache. Swelling of the salivary glands, specifically the parotid gland, is known as parotitis, and it occurs in 60–70% of infections and 95% of patients with symptoms. Mumps infection led to testicular swelling and orchitis in approx. 15 – 40% of infected males. The orchitis was usually one-sided, and subsequent infertility was rare.

Lower urinary tract infection

Men over 45 have a higher risk of lower urinary tract infections due to prostatic hyperplasia, which leads to obstruction of the urethra and incomplete emptying of the bladder. This enables bacteria, most commonly Escherichia coli, to thrive and cause urinary tract infections. The infection may then spread to the genital tract and cause epididymoorchitis.

Sexually-transmitted infection

In men younger than 45, sexually-transmitted infections (STIs), such as Chlamydia trachomatis and Neisseria gonorrhoeae are the most common causes of epididymoorchitis. STIs can have few or no symptoms and therefore, they can be transmitted easily by sexual intercourse with an infected individual. Symptoms include mainly discharge from the urethra, which may be milky white or yellow, and painful urination.



Extensive destruction of the testicular tissue due to the infection may lead to azoospermia (no sperm cells present in the semen) and male infertility. However infertility usually occurs only in cases of bilateral orchitis with severe damage to both of the testes, and is generally rare in cases of mumps orchitis.


Chlamydia trachomatis, one of the causative agents of epididymoorchitis mainly in young men, can also cause infection of the eye. Chlamydia conjunctivitis (inflammation of the conjunctiva, a mucous membrane on the surface of the eye) or trachoma was once the most important cause of blindness worldwide. The infection can be spread from eye to eye by fingers, shared towels or cloths, coughing and sneezing, and eye-seeking flies. Newborns can also contract chlamydia eye infection during childbirth.

Risk factors

  • mumps infection
  • urinary infection
  • prostatic hyperplasia 
  • sexually-transmitted infection
  • multiple sexual partners


Orchitis is usually preventable, but the methods of prevention are different for each specific cause.

The most effective preventive measure against mumps orchitis is the mumps vaccine. The vaccine may be given separately or as part of the MMR immunization vaccine that also protects against measles and rubella. The WHO (World Health Organization) recommends the use of mumps vaccines in all countries with well-functioning childhood vaccination programs. The American Academy of Pediatrics recommends the routine administration of MMR vaccine at ages 12–15 months and at 4–6 years. In some locations, the vaccine is given again between 4 to 6 years of age, or between 11 and 12 years of age if not previously given. The efficacy of the vaccine depends on the strain of the vaccine, but is usually around 80%.

In young adults, prevention is possible mainly by preventing a sexually-transmitted infection. Limiting the number of sexual partners and using a condom are among the most important preventive measures.

In older males, the probability of an urinary tract infection can be reduced by proper treatment of any abnormality in the urinary tract, most commonly benign prostatic hyperplasia. Once the urinary infection has set in, it is important to treat it adequately with antibiotics to prevent it from spreading into the genital tract.

Both acute and chronic infection can cause partial or complete obstruction of sperm transport (oligozoospermia or azoospermia), and subsequently reduced fertility or male infertility. Chronic inflammatory changes in the seminiferous tubules in orchitis are expected to disrupt the normal process of spermatogenesis (production of sperm) and cause alterations in sperm number and quality. Inflammation may act as a co-factor of infertility. Pressure-induced rupture of the epididymal duct will disrupt the blood–testis barrier, activate an immunological defense reaction, and induce the production of anti-sperm antibodies. It is suggested that 15% of male infertility is related to genital tract infection. The prevalence of MG in male of infertile couples found to be higher than normal.

The prognosis of orchitis is usually excellent. In young patients in whom epididymoorchitis is due to a sexually transmitted disease, acute epididymoorchitis usually resolves within 2 weeks of the initiation of medical therapy. In men older than the age of 40, 90% of cases of epididymitis resolve within 30 days of treatment.

Although inflammation and damage to testicular tissue may lead to impaired sperm production and lowered fertility, infertility is rare and is usually associated with severe cases of bilateral orchitis (affecting both testes). In epididymoorchitis, when the disease cannot be cured by antibiotics, orchiectomy has to be performed.

Find more about related issues


Orchitis ―sourced from Wikipedia licensed under CC BY- SA 3.0
Microbial Infections and Male Infertility ―by Samiappan and Jayaramasamy licensed under CC BY 3.0
ORCHITIS ―sourced from Fertilitypedia.org licensed under CC BY- SA 4.0
Mumps ―sourced from Fertilitypedia.org licensed under CC BY- SA 4.0
Chlamydia infection ―sourced from Fertilitypedia licensed under CC BY-SA 4.0
Epididymoorchitis ―sourced from Wikidoc licensed under CC BY-SA 3.0
Human testicle ―by Amada44 licensed under CC BY-SA 3.0
Epididymis ―by Anatomist90 licensed under CC BY-SA 3.0
Mumps ―by Center for Disease Control and Prevention's licensed under CC0 1.0
Creative Commons License
Except where otherwise noted, content on this site is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License, involving multiple copyrights under different terms listed in the Sources section.