Also Known As
Inflammation of the epididymis, Epididymo-orchitis (when testicular inflammation is also present).³
Definition
Epididymitis is an inflammation of the epididymis, a coiled tube located at the back of the testicle that is responsible for storing and transporting sperm.¹ It can affect males of any age.² The condition is primarily caused by bacterial infections, which can include sexually transmitted infections (STIs) like gonorrhea or chlamydia, particularly in younger, sexually active individuals.¹˒² In some instances, the inflammation can also involve the testicle itself, a condition referred to as epididymo-orchitis.¹ Treatment typically involves antibiotics to address the infection and supportive measures to alleviate discomfort.²
Clinical Context
Epididymitis is a clinical syndrome characterized by pain, swelling, and inflammation of the epididymis, which can sometimes involve the testicle (epididymo-orchitis).⁴ It is a common cause of acute scrotal pain in adult men.¹ Clinically, it presents with unilateral testicular pain and tenderness, often with a gradual onset, and may be accompanied by hydrocele and palpable swelling of the epididymis.⁴ Urinary symptoms such as dysuria, frequency, or urgency may also be present.¹
Patient selection for specific treatment pathways depends on the suspected etiology. In sexually active men younger than 39, epididymitis is frequently caused by sexually transmitted infections (STIs) such as Chlamydia trachomatis and Neisseria gonorrhoeae.¹˒⁴ In these cases, treatment is directed at these pathogens. For men older than 39, or those not sexually active in a way that would expose them to common STIs, enteric organisms like Escherichia coli are more common causes, often associated with bladder outlet obstruction (e.g., benign prostatic hyperplasia) or recent urologic instrumentation.¹˒⁴
Diagnostic considerations include a thorough history and physical examination. Objective evidence of inflammation (e.g., via urethral smear or urine tests for white blood cells) and NAAT testing for C. trachomatis and N. gonorrhoeae are crucial, along with urine cultures to identify other bacterial pathogens.⁴ A key differential diagnosis is testicular torsion, a surgical emergency, which typically presents with a more sudden onset of severe pain; ultrasound can be valuable in distinguishing these conditions, though clinical evaluation remains paramount.⁴
Management of acute epididymitis primarily involves antimicrobial therapy. Presumptive therapy is often initiated before all lab results are available, tailored to the likely pathogens based on age and sexual history.⁴ Treatment goals include microbiological cure, symptom improvement, prevention of STI transmission, and reduction of complications like infertility or chronic pain.⁴ Supportive measures include rest, scrotal elevation, analgesics (e.g., NSAIDs), and cold packs to alleviate discomfort.¹ Most cases can be managed on an outpatient basis, but hospitalization may be necessary for severe pain, fever, or suspicion of more complex conditions like abscess or testicular infarction.⁴
Expected outcomes are generally favorable with appropriate and timely antibiotic treatment, leading to resolution of infection and symptoms.¹˒⁵ Complications, though less common with adequate treatment, can include abscess formation, testicular infarction (rarely), chronic epididymitis (pain lasting >6 weeks), and reduced fertility.¹˒⁴ Chronic epididymitis, which may have infectious or non-infectious causes (including idiopathic), can be challenging to manage and may require referral to a urologist for further evaluation and treatment.⁴