A 22-year-old man presents with purulent urethral discharge. Gram stain of the discharge shows Gram-negative intracellular diplococci. The isolate grows on modified Thayer-Martin (MTM) medium. The isolate is found to produce beta-lactamase (PPNG). What is the first-line treatment?
- A Ciprofloxacin 500 mg orally single dose
- B Amoxicillin 3 g plus probenecid orally
- C Ceftriaxone 500 mg IM single dose plus azithromycin 1 g orally ✓
- D Spectinomycin 2 g IM single dose
Explanation
Gonorrhoea due to Neisseria gonorrhoeae requires treatment covering the prevalence of resistance. Penicillinase-producing N. gonorrhoeae (PPNG) encodes beta-lactamase on the plasmid TEM-1 and is resistant to penicillin. WHO and CDC guidelines recommend ceftriaxone 500 mg IM (1 g if weight >150 kg) as the primary treatment, combined with azithromycin 1 g orally to cover co-infection with Chlamydia trachomatis (which cannot be distinguished clinically). Fluoroquinolones (ciprofloxacin) are no longer recommended due to widespread resistance. Spectinomycin is reserved for cephalosporin allergy. Dual therapy also slows emergence of ceftriaxone resistance.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.