Epididymoorchitis: A Comprehensive Medical Guide
Overview
Epididymoorchitis is an inflammation of both the epididymis (the coiled tube that stores and carries sperm) and the testicle (orchis). The condition is usually referred to as “epididymitis” when only the epididymis is involved, but when the infection or inflammation spreads to the testicle, the term epididymoorchitis is used.
The condition can affect males of any age, but the underlying cause varies with age:
- Adolescents and young adults (15‑35 years) – most cases are linked to sexually transmitted infections (STIs) such as Chlamydia trachomatis or Neisseria gonorrhoeae.
- Older men (≥ 50 years) – infections often arise from urinary tract pathogens like Escherichia coli that travel up the urethra or from prostate procedures.
According to the U.S. Centers for Disease Control and Prevention (CDC), epididymoorchitis accounts for roughly 1–2 % of male urologic emergency department visits. Worldwide prevalence is difficult to pinpoint because many cases are treated empirically in primary care, but in high‑income countries the annual incidence is estimated at 10–15 per 100,000 men.
Symptoms
Symptoms usually develop over a few days and can range from mild discomfort to severe pain. Common features include:
- Pain – A gradual or sudden ache that starts in the scrotum and may radiate to the groin, lower abdomen, or lower back. Pain often worsens with movement, coughing, or straining.
- Swelling – The affected testicle becomes enlarged, tender, and may feel “rubbery.” The overlying skin can appear red or warm.
- Fever & chills – Systemic signs of infection are common, especially when bacterial pathogens are involved.
- Urinary symptoms – Dysuria, urgency, frequency, or cloudy/strong‑smelling urine suggest a concurrent urinary tract infection (UTI).
- Discharge – In STI‑related cases, a urethral discharge may be present.
- Testicular mass – A tender lump may be felt; it is usually the inflamed epididymis rather than a tumor.
- Nausea or vomiting – Less common, but can occur with high fever.
Causes and Risk Factors
Infectious Causes
- Sexually transmitted infections – C. trachomatis (most common) and N. gonorrhoeae account for > 60 % of cases in men < 35 years old.1
- Enteric bacteria – E. coli, Klebsiella, and Pseudomonas species often arise from urinary reflux in older men.
- Other pathogens – M. tuberculosis (rare), viral orchitis (e.g., mumps) may involve the epididymis.
Non‑infectious Causes
- Trauma – Direct blows to the groin can cause inflammation.
- Urinary reflux – Retrograde flow of urine into the ejaculatory ducts, more common after prostate surgery.
- Autoimmune or inflammatory disorders – Rare cases linked to systemic vasculitis.
Risk Factors
- Multiple sexual partners or unprotected intercourse (STI risk)
- Recent urinary catheterization, cystoscopy, or prostate biopsy
- History of prior epididymitis or orchitis
- Diabetes mellitus or immune‑compromising conditions
- Urinary tract obstruction (e.g., enlarged prostate)
Diagnosis
Early diagnosis reduces the risk of complications. The evaluation consists of a targeted history, physical exam, and selected laboratory/imaging studies.
Clinical Examination
- Inspection for erythema, swelling, or asymmetry.
- Palpation – the epididymis is usually tender, and the testicle may be firm but not hard (hardness suggests tumor).
- Prehn’s sign – relief of pain with gentle elevation of the scrotum is typical of epididymoorchitis, whereas torsion pain often worsens.
Laboratory Tests
- Urinalysis & urine culture – Detects pyuria, bacteriuria, and identifies causative organisms.
- Urethral swab or nucleic acid amplification test (NAAT) – Recommended for men < 35 years or those with STI risk factors to test for C. trachomatis and N. gonorrhoeae.2
- CBC – May show leukocytosis if infection is systemic.
Imaging
- Scrotal Doppler ultrasound – First‑line imaging; demonstrates an enlarged, hyperemic epididymis and testicle. It also helps exclude testicular torsion, tumors, or abscesses.
- CT or MRI – Reserved for atypical cases or when an intra‑abdominal source is suspected.
Treatment Options
Antibiotic Therapy
Empiric antibiotics should be started promptly after cultures are obtained.
| Age / Likely Pathogen | First‑line Regimen (7–14 days) |
|---|---|
| ≤ 35 years (STI‑related) | Azithromycin 1 g PO single dose **plus** Ceftriaxone 250 mg IM single dose *or* Doxycycline 100 mg PO twice daily for 10 days (if chlamydia only) |
| ≥ 35 years (enteric bacteria) | Ciprofloxacin 500 mg PO twice daily for 10‑14 days **or** Levofloxacin 500 mg PO once daily for 10‑14 days |
For penicillin‑allergic patients, alternatives include trimethoprim‑sulfamethoxazole or a fluoroquinolone with a macrolide.
Supportive Care
- Scrotal support – Wear an athletic supporter or tight‑fitting underwear.
- Ice packs – Apply for 15 minutes every hour for the first 24–48 hours to reduce swelling.
- Pain control – NSAIDs (ibuprofen 400‑600 mg PO every 6 hours) or acetaminophen.
- Hydration – Increase fluid intake to help flush bacteria from the urinary tract.
Procedural Interventions
- Abscess drainage – If a localized collection forms, percutaneous or surgical drainage is required.
- Urological evaluation – Persistent obstruction (e.g., prostatic enlargement) may need catheterization or transurethral resection.
When to Adjust Therapy
If symptoms worsen after 48–72 hours of appropriate antibiotics, reassess with repeat ultrasound and consider resistant organisms or an underlying abscess.
Living with Epididymoorchitis
Day‑to‑Day Management
- Rest – Limit vigorous activity, heavy lifting, and cycling for at least 1‑2 weeks.
- Hygiene – Gentle cleansing of the scrotal area; avoid harsh soaps.
- Follow‑up – Return to your clinician within 3–5 days to confirm clinical improvement.
- Sexual activity – Abstain until the full course of antibiotics is completed and symptoms have resolved (usually 7 days). Use condoms thereafter to prevent STI recurrence.
Psychosocial Considerations
Scrotal pain can cause anxiety about fertility. Reassure patients that, when treated promptly, long‑term fertility is rarely affected. If infertility is a concern, a semen analysis after recovery can provide reassurance.
Prevention
- Practice safe sex: consistent condom use and regular STI screening for sexually active individuals.
- Prompt treatment of UTIs and any urinary catheterization; maintain proper catheter hygiene.
- Avoid prolonged compression of the groin (e.g., tight cycling shorts) if you have a history of recurrent epididymitis.
- Manage chronic conditions such as diabetes or benign prostatic hyperplasia that increase infection risk.
- Stay up to date with vaccinations—mumps infection in adulthood can cause viral orchitis and predispose to secondary bacterial infection.
Complications
When left untreated or inadequately treated, epididymoorchitis can lead to:
- Abscess formation – Requires drainage and can damage testicular tissue.
- Testicular atrophy – Shrinkage of the testicle, potentially affecting hormone production and sperm output.
- Infertility – Rare but possible if scarring obstructs the epididymal duct.
- Chronic scrotal pain – May persist for months after infection resolves.
- Sepsis – Systemic spread of infection, especially in immunocompromised patients.
When to Seek Emergency Care
- Sudden, severe scrotal pain that develops within minutes.
- Scrotal swelling accompanied by high fever (> 38.5 °C / 101.3 °F), rapid heart rate, or dizziness.
- Vomiting, inability to pass urine, or a painful, enlarged abdomen.
- Signs of sepsis – chills, confusion, low blood pressure.
- Sudden loss of the testicle’s shape or a hard, rock‑like consistency (possible testicular torsion).
These symptoms may indicate testicular torsion, a ruptured abscess, or systemic infection, all of which require urgent medical intervention.
References
- Mayo Clinic. Epididymitis. https://www.mayoclinic.org. Accessed June 2026.
- Centers for Disease Control and Prevention. Sexually transmitted diseases treatment guidelines, 2023. https://www.cdc.gov.
- NIH National Institute of Diabetes and Digestive and Kidney Diseases. Epididymitis. https://www.niddk.nih.gov.
- Cleveland Clinic. Epididymitis and epididymoorchitis: Symptoms, causes, and treatment. https://my.clevelandclinic.org.
- World Health Organization. Guidelines on the Management of Sexually Transmitted Infections, 2021. https://www.who.int.