← Diagnosis and Management Guides
Infective Endocarditis
Key considerations: Septic emboli (stroke, splenic/renal infarcts), Valvular destruction, Heart failure
Cannot miss
- Septic emboli (stroke, splenic/renal infarcts)
- Valvular destruction
- Heart failure
- Mycotic aneurysm
Likely diagnoses
- Native valve endocarditis
- Prosthetic valve endocarditis
- IVDU-associated (tricuspid)
- Culture-negative endocarditis
Red flags
- New murmur
- Embolic phenomena (stroke, Janeway lesions, splinter hemorrhages)
- Persistent bacteremia
- Heart failure
Workup
- history: Fever, night sweats, weight loss, IVDU, prosthetic valve, recent dental procedure; exam: New or changing murmur, Osler nodes, Janeway lesions, Roth spots, splinter hemorrhages, splenomegaly; labs: Blood cultures x3 from different sites BEFORE antibiotics; CBC, BMP, ESR, CRP, RF, complement levels, urinalysis; imaging: TTE first, then TEE if TTE negative but clinical suspicion remains high (TEE sensitivity ~95%); bedside: POCUS for vegetations (limited sensitivity)
Management
- immediate: Blood cultures x3, then empiric antibiotics: vancomycin + ceftriaxone (native valve); Prosthetic valve: vancomycin + gentamicin + rifampin; general: 4-6 weeks IV antibiotics (organism-specific); Surgical indications: heart failure, persistent infection, large vegetations (>10mm), embolic events, prosthetic valve with dysfunction
Disposition
- admit: All confirmed or suspected endocarditis; discharge: After clinical improvement with OPAT (outpatient parenteral antibiotic therapy) if eligible; consults: ID, cardiology, CT surgery for surgical evaluation
Clinical pearls
- Modified Duke criteria: 2 major, 1 major + 3 minor, or 5 minor criteria for definite diagnosis
- IVDU endocarditis: tricuspid valve most common, S. aureus most common organism
- Blood cultures BEFORE antibiotics — even 1 dose reduces culture yield significantly
Source and review
- AHA Endocarditis Guidelines 2015. Last reviewed: 2024-11-01