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Medical error disclosure — USMLE Step 3 MCQ

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HardEthics, Patient Safety, Quality Improvement, Systems-Based PracticeMedical error disclosureUSMLE Step 3

A clinician has documented anti-HBs 48 mIU/mL after a complete HepB series and sustains a needlestick from an HBsAg-positive source. What is needed?

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Correct answer: C — Provide no HBIG and no additional HepB vaccine

The best answer is “Provide no HBIG and no additional HepB vaccine”. A documented vaccine responder remains protected despite later antibody waning. After exposure to an HBsAg-positive or unknown source, an unvaccinated clinician receives HBIG plus HepB vaccine immediately; a documented vaccine responder needs no action. The alternatives use a different threshold, timing, population, or intervention and therefore do not match the clinical facts presented.

Reference: CDC: Responding to HBV Exposures in Health Care Settings: https://www.cdc.gov/hepatitis-b/hcp/infection-control/index.html