Gonorrhea
System: Genitourinary Infections · Parent MOC: MOC - Diseases by System
One-Sentence Definition
Gonorrhea is a sexually transmitted infection caused by Neisseria gonorrhoeae, presenting as urethritis/cervicitis and capable of causing disseminated infection, PID, and neonatal ophthalmia — with rapidly evolving antimicrobial resistance.
Clinical Presentation
- Urethritis: purulent discharge, dysuria (often symptomatic in men)
- Cervicitis/PID: often asymptomatic until complications
- Pharyngeal/rectal infection: frequently asymptomatic
- Disseminated gonococcal infection (DGI): arthritis-dermatitis syndrome, tenosynovitis
- Neonatal conjunctivitis if untreated maternal infection
Pathogens
| Organism | Notes |
|---|---|
| Neisseria gonorrhoeae | Gram-negative diplococcus; pilus phase variation |
| Coinfection | Chlamydia trachomatis common — test/treat per guidelines |
Pathogenesis
- Mucosal attachment/invasion; evades Complement System and Antibodies and Immunoglobulin Classes via surface variation (Antigenic Variation)
- Ascending infection → PID, infertility, ectopic pregnancy risk
Diagnosis
| Step | Test | Note |
|---|---|---|
| First-line | NAAT (PCR) on urine or swab | Cervical/urethral/pharyngeal/rectal as exposed |
| Culture | Selective media + AST | Required for susceptibility in many settings |
| Disseminated | Blood/ synovial fluid culture | Low yield but important when positive |
Treatment Principles
- Ceftriaxone-based regimens per local resistance guidelines + chlamydia coverage when not excluded
- Test-of-cure culture when indicated (pharyngeal failure concerns)
- Partner notification; abstain until treated
- Never rely on oral fluoroquinolones empirically — widespread resistance
Prevention
- Barrier protection; screening high-risk networks
- Neonatal prophylaxis (erythromycin/ other per locale) where applicable
Differential / Pitfalls
- NGU from chlamydia, Mycoplasma genitalium
- Treating without culture capacity in rising ceftriaxone MIC settings — stewardship + surveillance
Related
- Neisseria gonorrhoeae · Chlamydia trachomatis · Genitourinary Infections
- MOC - Antimicrobial Resistance (AMR) · MOC - Public Health & Epidemiology
Active Recall
- Why is culture still valuable despite NAAT?
- Common coinfecting organism?
- DGI classic triad features?