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Just culture — USMLE Step 3 MCQ

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HardEthics, Patient Safety, Quality Improvement, Systems-Based PracticeJust cultureUSMLE Step 3

A 58-year-old with a transcatheter aortic bioprosthesis is scheduled for dental scaling with gingival manipulation. He has no penicillin allergy and no active infection. Which prophylaxis is appropriate?

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Correct answer: E — Give amoxicillin 2 g orally 30–60 minutes before the procedure

The best answer is “Give amoxicillin 2 g orally 30–60 minutes before the procedure”. A transcatheter prosthetic valve is a highest-risk cardiac condition, and scaling manipulates gingiva. A single preprocedure amoxicillin dose is appropriate. Prolonged courses add harm, and prophylaxis is not extended routinely to nondental procedures without active infection.

Reference: AHA Scientific Statement: Prevention of Viridans Group Streptococcal Endocarditis: https://professional.heart.org/en/science-news/prevention-of-viridans-group-streptococcal-infective-endocarditis/top-things-to-know