Infective endocarditis (Dukes Criteria)

Definition: Infective endocarditis is a form of endocarditis, or inflammation, of the inner tissue of the heart (such as its valves) caused by infectious agents. The agents are usually bacterial, but other organisms can also be responsible.

Modified Dukes Criteria

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

• Viridans-group streptococci, or
• Streptococcus bovis including nutritional variant strains, or
• HACEK group, or
• Staphylococcus aureus, or
• Community-acquired Enterococci, in the absence of a primary focus

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

• Two 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)

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

Interpretation:

A definite diagnosis of infective endocarditis can be established if the following conditions are fulfilled:

• Two major criteria, or
• One major and three minor criteria, or
• Five minor criteria