Orchitis is swelling (inflammation) of one or both of the testicles.
Epididymo - orchitis; Testis infection
Orchitis may be caused by an infection. Many types of bacteria and viruses can cause this condition.
The most common virus that causes orchitis is mumps. It most often occurs in boys after puberty. Orchitis most often develops 4 to 6 days after the mumps begins.
Orchitis may also occur along with infections of the prostate or epididymis.
Risk factors for sexually transmitted orchitis include:
Risk factors for orchitis not due to an STI include:
A physical exam may show:
Tests may include:
Treatment may include:
Getting the right diagnosis and treatment for orchitis caused by bacteria can most often allow the testicle to recover normally.
You will need further testing to rule out testicular cancer if the testicle does not completely return to normal after treatment.
Mumps orchitis cannot be treated, and the outcome can vary. Men who have had mumps orchitis can become sterile.
Some boys who get orchitis caused by mumps will have shrinking of the testicles (testicular atrophy).
Orchitis may also cause infertility.
Other potential complications include:
Acute pain in the scrotum or testicles can be caused by twisting of the testicular blood vessels (torsion). This is a medical emergency that requires immediate surgery.
A swollen testicle with little or no pain may be a sign of testicular cancer. If this is the case, you should have a testicular ultrasound.
See your health care provider for an exam if you have testicle problems.
Get emergency medical help if you have sudden pain in the testicle.
Things you can do to prevent the problem include:
Mason WH, Gans HA . Mumps. In: Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 275.
McGowan CC. Prostatitis, epididymitis, and orchitis. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 110.
Pontari M. Inflammatory and pain conditions of the male genitourinary tract: prostatitis and related pain conditions, orchitis, and epididymitis. In: Partin AW, Domochowski RR, Kavoussi LR, Peters CA, eds. Campbell-Walsh-Wein Urology. 12th ed. Philadelphia, PA: Elsevier; 2021:chap 56.
Reviewed By: Kelly L. Stratton, MD, FACS, Associate Professor, Department of Urology, University of Oklahoma Health Sciences Center, Oklahoma City, OK. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.