Infective endocarditis (IE) denotes infection of the endocardial surface of the heart and implies the physical presence of microorganisms in the lesion. Although the heart valves are most commonly affected, the disease may also occur within the heart in the location of congenital septal defects or on the endocardial surface in areas of turbulent flow. Extracardiac infections of arteriovenous or arterioarterial shunts (patent ductus arteriosus), infection related to structural aortic arch anomalies, and infections of prosthetic materials such as vascular occluders and stents can also be included in this definition of similar clinical manifestations. Unfortunately, variability in the clinical presentation continues to make the diagnosis of IE clinically challenging. The Duke criteria for the diagnosis of IE have been developed1 and modified.2 These criteria have been validated in multiple studies and shown to be superior to other criteria for the diagnosis of IE in the pediatric population.3–5
Despite improvements in diagnosis and treatment, IE continues to be associated with high morbidity and mortality. There are several reasons for this persistent morbidity and mortality. Pediatric patients with IE are increasingly complex. In developed countries, the improved survival of children with congenital heart disease has led to a shift in the underlying condition for IE from rheumatic heart disease to congenital heart disease. In addition, there has been an increase in antibiotic-resistant organisms. Targeted antibiotic treatment is the ideal approach to the pharmacologic management of IE. Prevention of IE remains the standard of care, although practices in prophylaxis have been shown to vary widely. Successful management of IE is dependent on the close cooperation of cardiologists, cardiothoracic surgeons, infectious disease specialists, primary-care providers, and the patients themselves.
The true incidence of IE is difficult to determine because the criteria for diagnosis have changed and the methods of reporting vary in different series.6,7 An analysis based on strict case definitions often reveals that only a small proportion (∼20%) of clinically diagnosed cases are categorized as definite. IE occurs less commonly in children than in adults, with an estimated incidence of one case per 1280 pediatric admissions per year8 vs. approximately one case per 1000 adult hospital admissions per year. However, the incidence of IE in the pediatric population has increased in the past 20 years9 potentially, in part, because of the improved survival of higher-risk neonates.
While the incidence of IE in pediatric patients has been increasing, the disease remains relatively uncommon in children and infants, in whom it is associated primarily with nosocomial bacteremia in the setting of underlying structural congenital heart disease.10,11 The incidence of IE in unrepaired congenital heart lesions has become rare because of surgical advances, which have enabled the correction or palliation of nearly all of these defects. The most common repaired congenital heart lesions predisposing to IE in children include aortic valve stenosis, pulmonary atresia, tetralogy of Fallot, complete atrioventricular canal defect, ...