Infectious urethritis
Infectious urethritis is inflammation of the urethra from a sexually transmitted pathogen, most often Neisseria gonorrhoeae, Chlamydia trachomatis, or Mycoplasma genitalium, presenting with dysuria and urethral discharge. Diagnosis rests on urethral or urine leukocytes plus nucleic acid amplification testing, and empiric treatment covers gonorrhea with ceftriaxone and chlamydia with doxycycline while results are pending.
- Topic reviewThe full article, organized the way the exam asks it.
- ABIM-format MCQsVignettes with an explanation for every wrong answer.
- Key factsThe numbers and thresholds worth memorizing, up front.
- AI tutorMedBrain answers the question you're stuck on.
What this article covers
- Overview
A sexually transmitted urethral infection: infectious urethritis is inflammation of the urethra caused by a sexually transmitted pathogen, presenting with dysuria, urethral pruritus, and mucoid to purulent discharge in men.
- Epidemiology
Highest incidence in young sexually active adults: persons aged 20 to 24 years are at highest risk for N.
- Risk factors
Unprotected sexual intercourse with a new or multiple partners: the primary behavioral risk factor for acquiring any of the causative organisms.
- Pathophysiology
Direct mucosal inoculation and ascending colonization: the causative organism is inoculated into the urethral mucosa during sexual contact and colonizes the urethral epithelium.
- Clinical features
Dysuria: burning or painful urination is the presenting symptom that brings most patients to care.
- Differential diagnosis
Cystitis: urinary urgency and frequency with suprapubic tenderness, but urine culture grows a uropathogen and urethral discharge is absent.
- Diagnosis
Infectious urethritis is confirmed by demonstrated urethral inflammation plus organism-specific testing: on gram-stained urethral smear, more than 2 white blood cells per high-power field has high…
- Management
First, start empiric therapy covering both gonorrhea and chlamydia at the time of diagnosis, before NAAT results return: give ceftriaxone 500 mg IM as a single dose (1 g IM single dose if body weight…
- Complications
Epididymitis: ascending infection into the epididymis causes unilateral testicular pain and swelling and requires an extended antibiotic course beyond that used for isolated urethritis.
- Prognosis
Excellent with prompt, appropriate antibiotic therapy: most cases of infectious urethritis are cured completely with a single course of the correct empiric or organism-directed regimen.
- Prevention
Screen women younger than 25 years, and women 25 years and older with risk factors, for N.
Read the whole article
Subscribing to Internal Medicine opens every article, the full question bank and MedBrain, on the web, iPhone and Android.
Related articles
- Chlamydia trachomatis infection
Chlamydia trachomatis is the most commonly reported bacterial sexually transmitted infection in the United States, frequently asymptomatic, and diagnosed by nucleic acid amplification testing of urine or genital/rectal/oropharyngeal swabs. Uncomplicated genital infection is treated with a single dose of azithromycin or a course of doxycycline, complications include pelvic inflammatory disease and epididymitis, and LGV serovars require a 21-day course and are an increasing cause of proctitis.
- Mycoplasma genitalium infection
Mycoplasma genitalium is an emerging sexually transmitted pathogen and a leading cause of nongonococcal, nonchlamydial urethritis in men and of cervicitis and pelvic inflammatory disease in women. Diagnosis requires nucleic acid amplification testing, and treatment is resistance-guided, with doxycycline lead-in therapy followed by extended azithromycin or moxifloxacin because macrolide resistance is increasingly common.
- Epididymitis
Epididymitis is inflammation of the epididymis, most often infectious, causing unilateral scrotal pain and swelling of gradual onset that must be distinguished urgently from testicular torsion. Diagnosis is clinical, supported by a positive Prehn sign and preserved cremasteric reflex, and treatment is empiric ceftriaxone plus doxycycline for age under 35 or STI risk, or levofloxacin alone for age over 35 with enteric-organism risk.
- Reactive arthritis
Reactive arthritis is a sterile, human leukocyte antigen B27 (HLA-B27)-associated spondyloarthritis that follows a genitourinary or enteric infection by 1 to 4 weeks, producing asymmetric lower-limb oligoarthritis, enthesitis, and the urethritis-conjunctivitis-arthritis triad. It is a clinical diagnosis of a culture-negative joint. First-line treatment is an NSAID such as piroxicam for at least 2 weeks, escalating to glucocorticoids and then sulfasalazine or a tumor necrosis factor (TNF) inhibitor for disease persisting beyond 3 to 6 months.
- Pelvic inflammatory disease
Pelvic inflammatory disease is an ascending polymicrobial infection of the upper female genital tract, most often caused by Neisseria gonorrhoeae, Chlamydia trachomatis, or Mycoplasma genitalium, diagnosed clinically on uterine, adnexal, or cervical motion tenderness. Most women are treated as outpatients with a single dose of ceftriaxone plus 14 days of doxycycline, while parenteral cefotetan or cefoxitin plus doxycycline, or clindamycin plus gentamicin, is reserved for hospitalized patients, with tubo-ovarian abscess and infertility among the major complications of delayed treatment.
- Acute prostatitis
Acute bacterial prostatitis is a sudden bacterial infection of the prostate presenting with local urinary symptoms plus fever, chills, and a tender boggy prostate on exam. Diagnosis is clinical, confirmed by urinalysis and culture, and treatment is empiric antibiotics chosen by patient age and risk, continued for 2-4 weeks.