MedCalc: Duke Criteria for Infective Endocarditis

Major criteria :

Positive blood culture for Infective Endocarditis

Typical microorganism consistent with IE from 2 separate blood cultures, as noted below:

• viridans streptococci, Streptococcus bovis, or HACEK group (what's this?), or

• community-acquired Staphylococcus aureus or enterococci, in the absence of a primary focus

Microorganisms consistent with IE from persistently positive blood cultures defined as:

• 2 positive cultures of blood samples drawn >12 hours apart, or

• all of 3 or a majority of 4 separate cultures of blood (with first and last sample drawn 1 hour apart)

Evidence of endocardial involvement

Positive echocardiogram for IE defined as :

• oscillating intracardiac mass on valve or supporting structures, in the path of regurgitant jets, or on implanted material in the absence of an alternative anatomic explanation, or

• abscess, or

• new partial dehiscence of prosthetic valve

New valvular regurgitation (worsening or changing of preexisting murmur not sufficient)

Minor criteria :

Predisposition: predisposing heart condition or intravenous drug use
Fever: temperature > 38.0° C (100.4° F)

Vascular phenomena: major arterial emboli, septic pulmonary infarcts, mycotic aneurysm, intracranial hemorrhage, conjunctival hemorrhages, and Janeway lesions

Immunologic phenomena: glomerulonephritis, Osler's nodes, Roth spots (what's this?), and rheumatoid factor

Microbiological evidence: positive blood culture but does not meet a major criterion as noted above¹ or serological evidence of active infection with organism consistent with IE

Echocardiographic findings: consistent with IE but do not meet a major criterion as noted above

¹ Excludes single positive cultures for coagulase-negative staphylococci, diphtheroids, and organisms that do not commonly cause endocarditis.

• Durack DT, Lukes AS, Bright DK. New criteria for diagnosis of infective endocarditis: utilization of specific echocardiographic findings. Duke Endocarditis Service. American Journal of Medicine. 96(3):200-9, 1994.