Trends and Microbiology of Infective Endocarditis in Children during 2000-2010 in United States
Infective endocarditis (IE) is rare in children. We studied the incidence, trend and microbiology of IE in children over the past 11 years using Nationwide Inpatient Sample (NIS) database. NIS database is the largest all-payer inpatient care database in the United States containing data on more than 8 million hospital stays from over 1,000 hospitals.
Using data from NIS database from 2000 to 2010, hospital admissions with primary discharge diagnosis of IE in children aged ≤19 years old were studied. Incidence was calculated based on total number of children in respective years from US Census. Children with underlying congenital heart defects (ventricular septal defect, hypoplastic left heart etc.) as well as other acquired heart conditions (rheumatic heart disease, cardiac transplant) were identified. Microbiological causative agents were identified from the discharge diagnosis. Linear regression was used to assess trend of incidence of IE admissions over time.
There was a total of 3,840 (95% CI: 3,395-4,285) admissions with IE with an overall incidence of 4.25 per million children. 27.2% were ≤5years, 16.6% were 6-10 years and 56.2% were ≥11 years old. 52.2% had an underlying heart disease. Overall 30.2% of cases were culture negative. Of those with culture-positive IE, Streptococcus species was most common (40.1%) followed by Staphylococcus aureus (36.6%). 26% of the culture- positive IE were due to viridans streptococci group (VSG). VSG was most common in those with underlying heart disease (32.9%) and Staphylococcus aureus was most common in those without heart disease (47.0%). The incidence of IE was stable over the study period (p=0.4 for trend). Among those with positive cultures, there was a significant decline in proportion of Staphylococcus aureus IE (slope -1.9; p=0.01) and a trend towards increase in proportion of VSG IE (slope +1.4; p=0.1). The overall mortality of IE was 2.8%. Among culture-positive patients Staphylococcal IE had the highest mortality (5.0%).
The incidence of IE in children has remained unchanged in the US over the last 11 years. However, the microorganisms causing IE seem to be changing with significant decrease in Staphylococcus aureus among culture-positive patients. Overall, Streptococcus spp was the most common cause of culture-positive IE.
E. McGrath, None
B. Asmar, None