What is the cause and treatment of a white penile discharge?

White Penile Discharge: Causes and Treatment

Primary Diagnosis and Immediate Management

White penile discharge in men is most commonly caused by urethritis from Chlamydia trachomatis or Neisseria gonorrhoeae, and empiric treatment should be initiated immediately with ceftriaxone 250 mg IM single dose PLUS doxycycline 100 mg orally twice daily for 10 days. 1, 2

Diagnostic Approach

Clinical Presentation

• Urethritis typically presents with mucopurulent or purulent urethral discharge, though asymptomatic infections are common 1
• Associated symptoms may include dysuria or urethral pruritis 1
• Visual inspection should identify the character of discharge, presence of lesions, or signs of inflammation 3

Essential Diagnostic Tests

• Gram-stained smear of urethral exudate showing ≥5 polymorphonuclear leukocytes per oil immersion field confirms urethritis 1, 2
• Nucleic acid amplification test (NAAT) for N. gonorrhoeae and C. trachomatis on intraurethral swab or first-void urine—this is the most sensitive and specific test available 1, 4
• First-void urine examination for leukocytes if urethral Gram stain is negative 2
• Syphilis serology and HIV testing should be offered to all patients 2

Etiology by Pathogen

Gonococcal vs Nongonococcal Urethritis

• Gonococcal urethritis: Diagnosed when Gram-negative intracellular diplococci are identified on urethral smear 1
• Nongonococcal urethritis (NGU): Diagnosed when intracellular diplococci are absent 1
  • C. trachomatis causes 15-55% of NGU cases, with lower prevalence in older men 1
  • Mycoplasma genitalium and Ureaplasma urealyticum are implicated but specific testing is not routinely indicated 1, 5
  • Trichomonas vaginalis and HSV occasionally cause NGU 1, 6

Treatment Recommendations

First-Line Empiric Therapy

When diagnostic tools are unavailable or while awaiting results, treat for both gonorrhea and chlamydia:

• Ceftriaxone 250 mg IM single dose 1, 2, 6
• PLUS Doxycycline 100 mg orally twice daily for 10 days 1, 2, 6

Alternative Regimens

For patients with cephalosporin or tetracycline allergies, or when enteric organisms are suspected (men >35 years):

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

Important Treatment Considerations

• Testing to determine specific etiology is strongly recommended because both infections are reportable and specific diagnosis improves partner notification and compliance 1
• The additional cost of treating NGU for both infections should motivate providers to establish a specific diagnosis 1
• Antibiotic resistance in M. genitalium is increasingly common, with one study showing 10 of 11 cases had resistance 5

Follow-Up and Complications

When to Reassess

• Reevaluation is mandatory if no improvement occurs within 3 days of treatment initiation 2
• Persistent discharge after completing therapy requires comprehensive evaluation for treatment failure or alternative diagnoses 2

Potential Complications

• Epididymitis: Sexually transmitted epididymitis usually accompanies urethritis and presents with unilateral testicular pain and tenderness 1, 2
• Reiter's syndrome: Can occur in men infected with C. trachomatis 1
• Increased HIV concentration in semen is associated with urethritis 6

Partner Management

All sexual partners from the 60 days preceding symptom onset must be evaluated and treated:

• Partners should receive the same empiric treatment regimen even without examination 1, 2
• Expedited partner treatment (giving prescriptions for unexamined partners) is advocated by the CDC and approved in many states 6
• Patients must avoid sexual intercourse until both they and their partners complete treatment and are symptom-free 2

Critical Differential Diagnoses

Conditions That Mimic Urethritis

• Epididymitis: Presents with testicular pain, swelling, and often accompanies urethritis in sexually active men 1, 2
• Testicular torsion: A surgical emergency that must be ruled out, especially with sudden severe pain—requires immediate specialist consultation 2, 3
• Perirectal abscess: Rare but can present with penile discharge; digital rectal examination should be performed if clinical suspicion exists 7

Age-Specific Considerations

• In men <35 years: Sexually transmitted pathogens (C. trachomatis, N. gonorrhoeae) are most common 1, 2
• In men >35 years: Enteric Gram-negative organisms from urinary tract infections are more common, warranting fluoroquinolone coverage 1, 2
• In prepubertal children: Consider sexual abuse if discharge is present; perform high-specificity testing before treatment 3

Common Pitfalls to Avoid

• Do not assume all discharge is sexually transmitted: Perirectal abscess, though rare, can present with penile discharge and requires digital rectal examination 7
• Do not delay treatment while awaiting test results: Empiric therapy should be initiated immediately to prevent complications and transmission 1, 6
• Do not forget testicular torsion: This surgical emergency must be excluded in all cases of acute genital pain, particularly with sudden onset 2, 3
• Do not neglect partner treatment: Failure to treat partners leads to reinfection and continued transmission 1, 2, 6