Epididymo-orchitis Empiric Therapy

General recommendations and empiric therapeutic regimens for epididymo-orchitis are provided below. Guidelines are based on epidemiology and therefore the appropriate choice of antibiotics requires a clinical assessment of the most likely etiology. The following are summarized below ^{[1, 2, 3, 4, 5]} :

• Treatment in young sexually active men with suspected sexually transmitted infection
• Treatment for suspected enteric organisms by age group
• Adjunctive/supportive therapy

General recommendations:

Acute epididymo-orchitis may be bacterial, nonbacterial, noninfectious, or idiopathic in origin. ^[6] Bacterial epididymo-orchitis tends to be caused by either urinary tract pathogens or by a sexually transmitted pathogen. ^[7]

Empiric antibiotic therapy is recommended only for presumed bacterial epididymitis and should be started before microbiological identification of the pathogen. ^[7]

Epididymo-orchitis from sexually transmitted infection (STI)

STI-associated epididymo-orchitis is more likely in men younger than 35 years with more than one partner in the past 12 months, particularly if urethral discharge is present. ^[8]

The 2021 guidelines from the US Centers for Disease Control and Prevention (CDC) recommend the following regimen for treatment aimed at eradication of Neisseria gonorrhoeae and Chlamydia trachomatis ^[9] :

• Ceftriaxone 500 mg (1 g in patients weighing ≥150 kg) IM once  plus
• Doxycycline 100 mg PO BID for 10 days 

For acute epididymitis in men who practice insertive anal sex ^[9] :

• Ceftriaxone 500 mg IM once  plus
• Levofloxacin 500 mg PO daily for 10 days

For first-line empirical treatment of epididymo-orchitis most probably due to any sexually transmitted pathogen, the 2020 United Kingdom British Association for Sexual Health and HIV (BASHH) guidelines recommend ^[10] :

• Ceftriaxone 1g IM plus
• Doxycycline 100 mg PO BID for 14 days

For epididymitis likely caused by sexually transmitted chlamydia and gonorrhoea and enteric organisms, BASHH guidelines recommend considering the following regimen ^[10] :

• Ceftriaxone 1g IM  plus
• Ofloxacin 200 mg PO BID for 10 days

For epididymo-orchitis most probably due to enteric pathogens, BASHH guidelines recommend considering the following regimen ^[10] :

• Ofloxacin 200 mg PO BID or
• Levofloxacin 500 mg PO once daily

If an STI is suspected, advise the patient to use condoms or abstain from sex for 7 days after treatment is initiated. ^[8] Sexual partners should be referred for evaluation and treatment to eliminate the possibility of reinfection.

Epididymo-orchitis from urinary pathogens

Epididymo-orchitis due to infection with gram-negative enteric organisms is most likely in men older than 35 years with a low-risk sexual history, with recent urological instrumentation or urinary tract infection, or with positive urine dipstick for leukocytes and nitrites. If an enteric organism is suspected, fluoroquinolones are the preferred antibiotic, as they have excellent penetration into the testes. ^{[7, 11]}

The CDC recommends the following regimen ^[9] :

• Levofloxacin 500 mg PO daily for 10 days

For acute epididymitis in men who practice insertive anal sex ^[9] :

• Ceftriaxone 500 mg IM once  plus
• Levofloxacin 500 mg PO daily for 10 days

BASHH guidelines recommends the following regimen be considered ^[10] :

• Ofloxacin 200 mg PO BID for 14 days or
• Levofloxacin 500 mg PO daily for 10 days

​If quinolones are contraindicated, BASHH recommends amoxicillin-clavulanate 625 mg PO TID for 10 days. ^[10]

For acute epididymitis in men who practice insertive anal sex ^[9] :

• Ceftriaxone 500 mg IM once  plus
• Ofloxacin 200 mg PO BID for 10 days

Prepubertal boys with suspected infection with enteric organisms

Options include the following:

• Trimethoprim/sulfamethoxazole 3-6 mg/kg PO q12h for 10d or
• Amoxicillin/clavulanate 15-20 mg/kg PO q12h for 10d

Adjunctive/supportive therapy

Approaches include the following:

• Reduce physical activity
• Scrotal support and elevation
• Ice packs
• Anti-inflammatory agents
• Analgesics, including nerve blocks
• Sitz baths
• Avoid urethral instrumentation