Doctor's Notes on Inflammation of the Testicle (Orchitis)
Inflammation of the testicle (also termed orchitis) is an inflammatory condition of one or both testicles in males, usually caused by a viral or bacterial infection. Signs and symptoms may range from mild to severe in one or both testicles and may have a rapid or gradual onset of pain and swelling in one or both testicles. Other signs and symptoms are testicular redness, tenderness, fever and chills, nausea, fatigue, headaches, body aches and pain with urination. It most commonly occurs in young boys as a result of viral infection (usually the mumps virus) although it may occur in some adult males.
Viruses cause most cases of orchitis, mainly the mumps virus but others such as varicella, coxsackievirus, echo virus and cytomegalovirus also can cause the disease. Less commonly, bacteria cause the disease; the bacteria can come from a prostate gland infection, urinary tract infection, or from a sexually transmitted disease. If the bacteria enter or infect the testicle from the epididymis, the condition is called epididymo-orchitis. In addition, there are rare reports of mumps orchitis occurring after immunization with the MMR vaccine.
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See AnswerREFERENCE:
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.