Utility of N-terminal pro-B-type natriuretic peptide to differentiate cardiac diseases from noncardiac diseases in young pediatric patients.

BACKGROUND Previous studies comparing children with cardiac disease with children with lung disease or healthy children indicated that natriuretic peptides are promising markers in pediatric patients. The aim of this study was to further clarify the diagnostic usefulness of N-terminal pro-B-type natriuretic peptide (NT-proBNP) measurements in a less preselected population of children younger than 3 years, a population in which clinical symptoms are frequently unspecific. METHODS NT-proBNP concentrations (Roche Diagnostics) were measured in sera of 142 pediatric patients (age range, 33-1070 days) presenting at the Gynaecologic and Pediatric Hospital (Linz, Austria) between January 2003 and January 2004. ROC curve analysis for the diagnostic performance of NT-proBNP, the Mann-Whitney U-test for group comparison, and linear regression analysis for influencing factors were performed. RESULTS NT-proBNP concentrations were significantly increased in infants with cardiac diseases [median (25th-75th percentile), 3681 (1045-13557) ng/L; n = 23] compared with infants with other diseases [241 (116-542) ng/L; n = 119], and ROC analysis revealed good performance for NT-proBNP in differentiating between infants with and without cardiac diseases [mean area under the curve (AUC) with 95% confidence interval (CI), 0.87 (0.76-0.94)]. A subgroup analysis of exactly age- and sex-matched infants was performed, which revealed results comparable to those for the whole study population [mean (95% CI) AUC, 0.84 (0.68-0.93)]. CONCLUSION In a heterogeneous group of pediatric patients < 3 years of age, NT-proBNP showed good diagnostic performance to distinguish between cardiac diseases and various noncardiac diseases.