Duke criteria for infective endocarditis

The Duke criteria are a set of clinical criteria set forward for the diagnosis of infective endocarditis.

For diagnosis of definite infective endocarditis by clinical criteria the requirement is ⁴: 

• 2 major criteria or

• 1 major and 3 minor criteria or

• 5 minor criteria

For diagnosis of possible infective endocarditis by clinical criteria the requirement is ⁴:

• 1 major and 1 minor criterion

• 3 minor criteria

For adequate diagnostic sensitivity, transesophageal echocardiography is the preferred modality used in patients designated "high-risk" or those in whom transthoracic echocardiography would likely be difficult. Examples of high-risk patients are those with ³:

• past medical history of endocarditis

• congenital heart disease

• physical exam significant for:

  • signs of heart failure

  • a new heart murmur

  • stigmata of infective endocarditis

• history of prosthetic heart valve implantation

Major criteria

• positive blood cultures for infective endocarditis

• typical microorganism for infective endocarditis from 2 separate blood cultures

  • Viridans streptococci, Streptococcus bovis, and HACEK group or 

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

  • persistently positive blood cultures, defined as recovery of a microorganism consistent with infective endocarditis from: 

    • 2 blood cultures drawn 12 hours apart or all of 3 or most of 4 or more separate blood cultures, with first and last drawn at least one hour apart

• evidence of endocardial involvement

  • positive echocardiogram for infective endocarditis

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

    • abscess or

    • new partial dehiscence of prosthetic valve or

  • new valvular regurgitation 

Minor criteria

• predisposing heart condition or intravenous drug use

• fever: 38°C 

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

• immunologic phenomena: 

  • glomerulonephritis

  • Osler nodes

  • Roth spots

  • rheumatoid factor

• microbiologic evidence: positive blood culture but not meeting major criterion as noted previously or serologic evidence of active infection with organism consistent with infective endocarditis 

• echocardiography findings consistent with infective endocarditis but not meeting major criteria as noted previously