| Major criteria |
| Positive blood cultures for IE (1 of the following): |
| Typical microorganisms consistent with IE from 2 separate blood cultures: |
| Staphylococcus aureus |
| Viridans streptococci |
| Streptococcus gallolyticus (formerly S. bovis), including nutritional variant strains (Granulicatella spp and Abiotrophia defectiva) |
| HACEK group – Haemophilus aphrophilus (subsequently called Aggregatibacter aphrophilus and Aggregatibacter paraphrophilus), Actinobacillus actinomycetemcomitans (subsequently called Aggregatibacter actinomycetemcomitans), Cardiobacterium hominis, Eikenella corrodens, Kingella kingae |
| Community-acquired enterococci in the absence of a primary focus, OR |
| Persistently positive blood culture: |
| For organisms that are typical causes of IE – At least 2 positive blood cultures from blood samples drawn >12 hours apart |
| For organisms that are more commonly skin contaminants – 3 or a majority of ≥4 separate blood cultures (with first and last drawn at least 1 hour apart) |
| Single positive blood culture for Coxiella burnetii or phase I IgG antibody titer >1:800* |
| Evidence of endocardial involvement (1 of the following): |
| Echocardiogram positive for IE: |
| Vegetation (oscillating intracardiac mass on a valve or on 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 |
| Increase in or change in preexisting murmur not sufficient |
| Minor criteria |
| Predisposition – Intravenous drug use or presence of a predisposing heart condition (prosthetic heart valve or a valve lesion associated with significant regurgitation or turbulence of blood flow) |
| Fever – Temperature ≥38.0°C (100.4°F) |
| Vascular phenomena – Major arterial emboli, septic pulmonary infarcts, mycotic aneurysm, intracranial hemorrhage, conjunctival hemorrhages, or Janeway lesions |
| Immunologic phenomena – Glomerulonephritis, Osler nodes, Roth spots, or rheumatoid factor |
| Microbiologic evidence – Positive blood cultures that do not meet major criteria, OR serologic evidence of active infection with organism consistent with IE |
| (Echocardiographic minor criteria eliminated)* |
