Trends, Microbiology, and Outcomes of Infective Endocarditis in Children During 2000-2010 in the United States

Background: We studied the incidence, trend, underlying conditions, microbiology, and outcomes of infective endocarditis (IE) in children during 11 years using Nationwide Inpatient Sample (NIS) database. This is the largest all-payer inpatient care database in the United States containing data for more than 8 million hospital stays from over 1000 hospitals.

Methods: NIS data from 2000 to 2010 of primary discharge diagnosis of IE in children aged ≤19 years old were studied. Children with underlying congenital heart defects and acquired heart conditions were identified. Microbiological causative agents were recorded. Linear regression was used to assess trend of incidence over time.

Results: An estimated 3,840 (95% CI: 3,395-4,285) children had a discharge diagnosis of IE. The overall incidence was 0.43 per 100 000 children. The incidence was stable over the study period (P = .4 for trend). The majority of patients 56.2% were ≥11 years old and 15.4% were ≤ 1 year. Underlying cardiac conditions were present in 53.5% of patients. Overall 30.2% of cases were culture-negative. Among those with identified pathogens, Staphylococcus species were most common (43.1%) followed by Streptococcus species (39.5%). Viridans Streptococcus group was most common in those with underlying heart disease (32.7%) and S. aureus was most common in those without heart disease (46.9%). Among culture-positive patients, there was a decline in proportion of Staphylococcal IE (P = .03) and an increase in proportion of Streptococcal IE (P = .04). Overall mortality was 2.8%. Patients with Staphylococcal IE had longer median length of stay (12 vs. 9 days; P < .01) and the highest mortality (4.7%).

Conclusion: The incidence of IE in children has remained unchanged in the United States during the 11-year study period. Among culture-positive patients there was a significant decrease in Staphylococcal IE and a significant increase of Streptococcal IE. Staphylococcal IE was associated with increased LOS and highest mortality.