A 30-year-old man presents with mucopurulent urethral discharge. Smear shows more than 5 polymorphonuclear leukocytes per high power field but Gram stain reveals no intracellular Gram-negative diplococci. Culture and nucleic acid amplification testing are positive for an obligate intracellular organism. The most likely causative agent is:
- A Neisseria meningitidis
- B Chlamydia trachomatis serovars D to K ✓
- C Trichomonas vaginalis
- D Mycoplasma hominis
Correct answer: B. Chlamydia trachomatis serovars D to K
Explanation
Non-gonococcal urethritis is defined by urethritis without intracellular Gram-negative diplococci on smear. Chlamydia trachomatis urogenital serovars D to K is the most common cause worldwide and in India. Serovars L1 to L3 cause lymphogranuloma venereum instead. Trichomonas vaginalis is a flagellated protozoan and a less common cause of NGU, Mycoplasma hominis is not established as a urethral pathogen, and Neisseria meningitidis is a rare urethral colonizer that would appear as Gram-negative diplococci.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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