Which statement correctly distinguishes Chlamydia pneumoniae from Chlamydia trachomatis?

• A Its elementary body contains glycogen detectable by iodine staining
• B It is treated with penicillins rather than macrolides
• C It primarily causes ocular and genital tract infections
• D Humans are its only known reservoir ✓

Explanation

Chlamydia pneumoniae (TWAR strain) has humans as its only reservoir, spreads person to person by respiratory droplets, and causes bronchitis, sinusitis, and community-acquired atypical pneumonia, with proposed links to atherosclerosis. In contrast, C. trachomatis has no non-human reservoir either, but option A is wrong because only C. trachomatis inclusions contain glycogen and stain with iodine. Option C describes C. trachomatis, and option B is false since both require macrolides or tetracyclines.

Reference: Jawetz, Melnick and Adelberg's Medical Microbiology, 28th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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