This is condition where an organism infects the endocardium. It is classified as acute or subacute.
Morality is 16-27% (S. Aureus 30-40% Streptococci ~10%)
Acute infective endocarditis
This happens when a high virulence organism finds itself in the blood stream and infects a valve. The valve does not have to have vegetations on it and is associated with IV drug usage. It is an acute disease which can present as acute malaise, fever, riguors and leukocytosis. This presents as rapid valve destruction. Often caused by: S. Aureus, S. pyogenes, Strep. pneumoniae, enterococcus, sometimes fungi.
Subacute infective endocarditis
Most often this is a condition where the sterile vegetations in rheumatic fever are infected by an bacteria in the blood (bacteraemia), and the septic vegetation that results ulcerates and destroys the valve. The vegetations can also break off and cause septic infarcts or abscesses in other organs. this is a low grade infection and presentation can take weeks or months. You see weight loss, fatigue, night sweats, murmur, low-no fever and no leukocytosis. Often caused by α-haemolytic streptococci or oral flora