Question
Nongonococcal urethritis
Answer
Non-gonococcal urethritis (NGU) refers to urethritis caused by an organism other than Neisseria gonorrhoeae — the most important sexually transmitted cause of urethral discharge/dysuria after gonococcal urethritis, and now the more common of the two in many settings.
Causative organisms: Chlamydia trachomatis (serovars D–K) — the single most common cause; Ureaplasma urealyticum and Mycoplasma genitalium; Trichomonas vaginalis.
Clinical features: milder, more mucoid discharge than gonococcal urethritis, with a longer incubation period (1–3 weeks vs. 2–7 days), and can be asymptomatic in a significant proportion of infected individuals. Untreated chlamydial infection can ascend to cause epididymitis in men and pelvic inflammatory disease/tubal infertility in women.
Laboratory diagnosis: Gram stain shows pus cells without intracellular Gram-negative diplococci; nucleic acid amplification test (NAAT/PCR) is the current gold standard for chlamydia detection.
Treatment: azithromycin (single dose) or doxycycline; treatment of sexual partners.