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CAP Duration NICE — SCE Infectious Diseases MCQ

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HardRespiratory InfectionCAP Duration NICESCE Infectious Diseases

Cardiobacterium hominis prosthetic-valve endocarditis is confirmed. The isolate has not undergone reliable beta-lactamase testing and there is no severe beta-lactam allergy. Which regimen is preferred?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: D — Ceftriaxone 2 g intravenously once daily for 6 weeks

Explanation lettering: B = shown as A · D = shown as B · E = shown as C · C = shown as D · A = shown as E

C is correct. Cardiobacterium is a HACEK organism. Because some HACEK isolates produce beta-lactamase and susceptibility testing may be unreliable, ceftriaxone is the standard directed treatment: four weeks for native-valve but six weeks for prosthetic-valve endocarditis. Ampicillin is an option only when beta-lactamase absence is established and then follows a longer course with early gentamicin. Fluoroquinolones are less validated alternatives, while carbapenem plus six weeks of aminoglycoside is unnecessarily broad and toxic.

Reference: ESC 2023 guideline for the management of endocarditis: https://academic.oup.com/eurheartj/article/44/39/3948/7243107