What is the recommended antibiotic regimen and supportive care for acute epididymitis in men under 35 years old (likely sexually transmitted) versus men over 35 years old or with recent urinary instrumentation?

Epididymitis Treatment

For men under 35 years old with suspected sexually transmitted epididymitis, give ceftriaxone 250 mg IM as a single dose PLUS doxycycline 100 mg orally twice daily for 10 days; for men over 35 years or those with recent urinary instrumentation, use levofloxacin 500 mg orally once daily for 10 days OR ofloxacin 300 mg orally twice daily for 10 days. 1, 2

Age-Based Treatment Algorithm

Men Under 35 Years (Sexually Transmitted Etiology)

First-line regimen:

• Ceftriaxone 250 mg IM single dose PLUS doxycycline 100 mg orally twice daily for 10 days 1, 2, 3
• This dual therapy targets Chlamydia trachomatis and Neisseria gonorrhoeae, which are the predominant pathogens in this age group 1, 2, 4
• C. trachomatis alone accounts for approximately two-thirds of cases in younger men, often without preceding urethral symptoms 5, 6

Alternative for cephalosporin/tetracycline allergy:

• Levofloxacin 500 mg orally once daily for 10 days OR ofloxacin 300 mg orally twice daily for 10 days 1, 2

Special consideration for men who practice insertive anal intercourse:

• Use ceftriaxone 250 mg IM single dose PLUS levofloxacin 500 mg orally once daily for 10 days (or ofloxacin 300 mg twice daily for 10 days) to cover both STI pathogens and enteric organisms 3

Men Over 35 Years (Enteric Organism Etiology)

First-line regimen:

• Levofloxacin 500 mg orally once daily for 10 days OR ofloxacin 300 mg orally twice daily for 10 days 1, 2, 3
• Escherichia coli is the predominant pathogen in this age group, typically associated with bladder outlet obstruction, benign prostatic hyperplasia, or recent urinary instrumentation 1, 2, 5, 4
• Fluoroquinolone monotherapy is sufficient because sexually transmitted infections are uncommon in this population 1, 2

Do NOT use the ceftriaxone plus doxycycline regimen in men over 35 years, as it targets STI pathogens and is inappropriate for enteric bacteria 2

Diagnostic Evaluation Before Treatment

For men under 35 years:

• Obtain urethral Gram stain (≥5 polymorphonuclear leukocytes per oil-immersion field indicates urethritis) 1, 2
• Perform nucleic acid amplification testing (NAAT) or culture from intraurethral swab or first-void urine for N. gonorrhoeae and C. trachomatis 1, 2
• If urethral Gram stain is negative, examine first-void urine for leukocytes 1, 2

For men over 35 years:

• Obtain urinalysis with microscopy to detect pyuria (≥5 WBCs per high-power field) 2, 7
• Perform urine culture and Gram stain to identify Gram-negative organisms 1, 2, 7

For all patients:

• Offer syphilis serology and HIV testing 1, 2
• Do not delay treatment while awaiting test results 2

Critical Differential Diagnosis

Testicular torsion must be excluded immediately in all cases, especially when:

• Pain onset is sudden and severe 1, 2
• Patient is an adolescent or young adult 1, 2
• Prehn sign is negative (no pain relief with scrotal elevation) 7
• Testicular torsion is a surgical emergency requiring immediate specialist consultation, as testicular viability is compromised within 6-8 hours 1, 2, 7

Supportive Care Measures

All patients should receive:

• Bed rest until fever and local inflammation subside 1, 2
• Scrotal elevation (use scrotal supporter to reduce edema) 1, 2, 7
• Analgesics for pain control 1, 2, 7

Follow-Up and Treatment Failure

Reassess within 3 days if no clinical improvement occurs 1, 2, 7

• Expect reduction in pain, swelling, and tenderness as markers of therapeutic response 2, 7
• Lack of improvement requires re-evaluation of both diagnosis and antibiotic choice 1, 2, 7

If symptoms persist after completing the full antibiotic course, conduct comprehensive evaluation for:

• Testicular tumor 1, 2
• Epididymal abscess 1, 2
• Testicular infarction 1, 2
• Testicular cancer 1, 2
• Tuberculous or fungal epididymitis (especially in immunosuppressed patients) 1, 2

Management of Sexual Partners

For STI-related epididymitis:

• Refer all sexual partners from the preceding 60 days for evaluation and treatment 1, 2
• Partners should receive empiric treatment covering both N. gonorrhoeae and C. trachomatis 2
• Patients must abstain from sexual intercourse until both they and their partners have completed therapy and are symptom-free 1, 2

Special Populations

HIV-positive patients:

• Treat with the same regimens as HIV-negative patients for uncomplicated epididymitis 1, 2
• Maintain higher suspicion for fungal and mycobacterial causes 1, 2

Patients requiring hospitalization:

• Consider admission for severe pain suggesting alternative diagnoses (torsion, abscess, infarction), high fever, or concerns about outpatient compliance 1, 2

Common Pitfalls to Avoid

• Never use ciprofloxacin as first-line therapy in men under 35 years, as it provides inadequate coverage for C. trachomatis 2
• Do not use trimethoprim-sulfamethoxazole (Bactrim) for epididymitis treatment, as it is not recommended by current guidelines 7
• Do not discontinue treatment prematurely even if symptoms improve rapidly; complete the full 10-day course 1
• Do not rely solely on urinalysis in men under 35 years, as STI-related epididymitis frequently presents without significant pyuria 7
• Do not fail to obtain urine culture before starting antibiotics in men over 35 years, as susceptibility testing guides therapy adjustments 2, 7