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Confidential adolescent care — USMLE Step 3 MCQ

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HardEthics, Patient Safety, Quality Improvement, Systems-Based PracticeConfidential adolescent careUSMLE Step 3

A 34-year-old man who has sex with men completed treatment for rectal gonorrhea 3 months ago and anticipates ongoing condomless sex. HIV testing is negative and he uses PrEP. After shared decision-making, which doxycycline postexposure plan matches CDC guidance?

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Correct answer: A — Take doxycycline 200 mg within 72 hours after sex, with no more than 200 mg in 24 hours

The best answer is “Take doxycycline 200 mg within 72 hours after sex, with no more than 200 mg in 24 hours”. A bacterial STI during the previous 12 months makes this patient eligible for counseling about doxy-PEP. The event-driven dose is 200 mg as soon as possible and within 72 hours after sex, capped at 200 mg per 24 hours, with ongoing STI testing and reassessment every 3–6 months. Eligible MSM and transgender women with a bacterial STI in the prior 12 months may take doxycycline 200 mg within 72 hours after sex, no more than 200 mg per 24 hours, with STI follow-up every 3–6 months. The alternatives use a different threshold, timing, population, or intervention and therefore do not match the clinical facts presented.

Reference: CDC Clinical Guidelines on Doxycycline PEP: https://www.cdc.gov/mmwr/volumes/73/rr/rr7302a1.htm