Infective endocarditis (IE) is defined as an infection of the
endocardium, generally involving cardiac valves and their valvular apparatus
such as the chordae tendinae, interventricular septum, mural endocardium,
or intracardiac devices. IE may occur in children with or without
antecedent underlying cardiac disease. The diagnosis of IE rests
on a constellation of clinical features and laboratory investigations,
including blood cultures and echocardiography.1 Most
often, IE presents with fever, positive blood cultures, a new murmur,
or vegetations by echocardiography. Vascular findings and immunologic
phenomena are common. The presenting symptoms, rate of progression, morbidity,
and mortality of infective endocarditis depend, in part, upon the
underlying heart disease, the etiologic organism, and host factors.
Whereas most infective endocarditis is accompanied by positive blood
cultures, 5% to 7% are culture negative, sometimes due
to administration of antibiotics before blood cultures were obtained.1 Compared
to adults, children have a lower incidence and fatality rate of
IE.2,3 The most common causes of bacterial endocarditis
in children are viridans group streptococci and Staphylococcus
aureus; other principal pathogenic agents include coagulase-negative
staphylococci, Streptococcus pneumoniae, HACEK
organisms (Haemophilus species, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis,
Eikenella corrodens, and Kingella species),
and enterococcus species.4-6 Emergence of antibiotic
resistance to these common pathogens has serious ramifications for
the morbidity and mortality of IE. It is therefore essential that pediatricians
and pediatric cardiologists work in concert with specialists in
infectious diseases in planning the treatment of IE.