Duke Criteria

Modified Duke criteria for infective endocarditis — definite / possible / rejected
Major criteria
Blood cultures typical of IE (typical organism ×2, persistent bacteraemia, or single Coxiella burnetii / phase I IgG > 1:800)
Endocardial involvement (echo vegetation, abscess, new prosthetic dehiscence, or new valvular regurgitation)
Minor criteria
Predisposing heart condition or injection drug use
Fever ≥ 38 °C
Vascular phenomena (arterial emboli, septic pulmonary infarcts, mycotic aneurysm, intracranial or conjunctival haemorrhage, Janeway lesions)
Immunological phenomena (glomerulonephritis, Osler nodes, Roth spots, rheumatoid factor)
Microbiological evidence not meeting a major criterion
Evidence
Original publication
Li JS, Sexton DJ, Mick N, et al. Proposed modifications to the Duke criteria for the diagnosis of infective endocarditis. Modified the 1994 Durack criteria: added S. aureus bacteraemia and Q fever as major criteria, removed "echocardiogram non-diagnostic" as a minor criterion, and clarified the "possible" category.
Clinical Infectious Diseases, 2000
Open source
Validation
Durack DT, Lukes AS, Bright DK. New criteria for diagnosis of infective endocarditis: utilization of specific echocardiographic findings. The original Duke criteria on which this classification is based.
American Journal of Medicine, 1994
Open source
Guideline
The 2023 Duke-ISCVID criteria (Fowler VG et al., Clin Infect Dis 2023; PMID 37138445) update the microbiological, imaging (cardiac CT, PET-CT) and surgical criteria and are increasingly the reference standard. All versions are classification — not clinical diagnostic — criteria; a "possible" or "rejected" result does not exclude endocarditis when clinical suspicion is high. This tool covers the clinical pathway only; pathological criteria and firm alternative diagnoses are assessed separately.
Last reviewed: 2026-09
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