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PrEP follow-up — USMLE Step 3 MCQ

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HardPreventive Medicine, Epidemiology, BiostatisticsPrEP follow-upUSMLE Step 3

A 31-year-old man taking daily tenofovir-emtricitabine PrEP reports fever, rash, pharyngitis, and a condomless exposure 18 days ago. A laboratory HIV antigen-antibody test is negative, but HIV-1 RNA is detectable below the assay quantification limit. Which next step is most appropriate?

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Correct answer: C — Hold PrEP and repeat blood antigen-antibody testing with quantitative HIV-1 RNA

The best answer is “Hold PrEP and repeat blood antigen-antibody testing with quantitative HIV-1 RNA”. Symptoms after a recent exposure plus discordant testing can represent very early HIV infection partially suppressed by PrEP. Continuing only two active drugs risks resistance if infection is present. CDC guidance calls for prompt repeat blood testing, including HIV-1 RNA, while PrEP is held until status is resolved.

Reference: CDC Clinical Guidance for PrEP: https://www.cdc.gov/hivnexus/hcp/prep/index.html