← Diagnosis and Management Guides
Infective Endocarditis
Key considerations: Embolic stroke from vegetation, Mycotic aneurysm, Perivalvular abscess
Cannot miss
- Embolic stroke from vegetation
- Mycotic aneurysm
- Perivalvular abscess
- Acute valvular regurgitation causing flash pulmonary edema
Likely diagnoses
- Native valve endocarditis
- Prosthetic valve endocarditis
- IVDU-associated tricuspid endocarditis
- Culture-negative endocarditis
Red flags
- New murmur in febrile patient
- IV drug use
- Prosthetic valve
- Prior endocarditis
- Osler nodes/Janeway lesions/Roth spots
- Embolic phenomena
Workup
- history: Fever duration, IVDU, prosthetic valve, recent dental work, prior endocarditis; exam: Cardiac auscultation (new or changing murmur), skin (Janeway lesions, Osler nodes, splinter hemorrhages), ophthalmologic (Roth spots), splenomegaly; labs: Blood cultures x3 from different sites BEFORE antibiotics (CRITICAL); CBC, BMP, ESR/CRP, UA (hematuria), rheumatoid factor; imaging: TTE first, TEE if prosthetic valve or negative TTE with high suspicion (TEE sensitivity ~95%); bedside: POCUS for vegetations and valvular function
Management
- immediate: Blood cultures x3 then empiric antibiotics — do not delay beyond cultures; Vancomycin + gentamicin (native valve) or vancomycin + gentamicin + rifampin (prosthetic valve); general: ID consult for organism-specific therapy; Long-course IV antibiotics (4-6 weeks); Serial echocardiography; CT surgery consult for surgical indications
Disposition
- admit: All confirmed or suspected endocarditis; discharge: After clinical improvement with OPAT if eligible; consults: ID, cardiology, CT surgery for surgical evaluation
Clinical pearls
- Duke criteria: 2 major, 1 major + 3 minor, or 5 minor = definite endocarditis
- Major criteria: positive blood cultures (typical organisms x2) and echo evidence
- Blood cultures BEFORE antibiotics — even 1 dose reduces culture yield significantly
Source and review
- AHA Endocarditis Guidelines 2023. Last reviewed: 2024-11-01