What is Urethritis
Urethritis is inflammation of the urethra caused by infection, characterized by urethral discharge (mucoid or purulent), burning during urination, or urethral discomfort, though asymptomatic infections are common. 1
Definition and Clinical Presentation
Urethritis manifests through several key features:
- Classic symptoms include dysuria, mucopurulent or purulent urethral discharge, penile itching or tingling, and urethral discomfort 2, 3
- Asymptomatic infections are common, making clinical diagnosis challenging and emphasizing the importance of objective testing 1
- The condition represents inflammation of the urethra specifically, distinguishing it from other urogenital syndromes like epididymitis, orchitis, or prostatitis 3
Diagnostic Criteria
Urethritis should be confirmed through objective evidence before treatment, not symptoms alone. 1 The diagnosis requires at least one of the following:
- Mucopurulent or purulent urethral discharge visible on examination 1, 2
- Gram stain of urethral secretions showing ≥5 white blood cells per oil immersion field (the preferred rapid diagnostic test) 1
- Positive leukocyte esterase test on first-void urine 1, 2
- Microscopic examination of first-void urine showing ≥10 white blood cells per high-power field 1, 2
Causative Organisms
The two primary bacterial pathogens are N. gonorrhoeae and C. trachomatis, which are reportable infections and require specific identification when possible. 1
For nongonococcal urethritis (NGU), the pathogen distribution includes:
- C. trachomatis: 23-55% of cases (most frequent cause) 1
- M. genitalium: increasingly recognized as a significant cause, potentially responding better to azithromycin than doxycycline 1, 4
- U. urealyticum: 20-40% of cases 1
- T. vaginalis: 2-5% of cases 1
- Herpes simplex virus and adenovirus: occasional causes 1
- Unknown etiology: up to half of NGU cases remain non-specific 4
Clinical Significance and Complications
Untreated urethritis leads to serious complications and ongoing transmission:
- In men with C. trachomatis infection: epididymitis and Reiter's syndrome 1
- Female sexual partners face risk of chlamydial infection with associated complications including pelvic inflammatory disease 1
- Urethritis facilitates HIV transmission through increased HIV concentration in semen 3
- Racial disparities persist, with gonorrhea rates 40 times higher in Black adolescent males compared to White adolescent males in the United States 3
Important Clinical Distinctions
A critical pitfall: The presence of urethritis must be documented with objective signs or laboratory evidence before treatment—symptoms alone are insufficient for diagnosis or re-treatment. 1 This prevents unnecessary antibiotic exposure and helps identify alternative diagnoses.
Gonococcal versus nongonococcal differentiation is essential because:
- Both infections are reportable to health departments 1
- Specific diagnosis improves treatment compliance and partner notification 1
- N. gonorrhoeae requires susceptibility testing due to emerging resistance 5
- The Gram stain provides immediate differentiation by identifying white blood cells containing gram-negative intracellular diplococci (GNID) in gonococcal urethritis 1