A retrospective observational study to estimate use of biomarkers to
predict severity of community acquired pneumonia in children
Abstract
Purpose: Multiple studies have investigated the role of biomarkers in
predicting pneumonia severity in adults but minimal research exists for
children. The aim of this study was to determine if the following
biomarkers: white blood cell count (WBC), platelet count, C-reactive
protein (CRP), procalcitonin (PCT), neutrophil-lymphocyte ratio,
neutrophil count, or band count predict community associated pneumonia
(CAP) severity in children. Methods: A retrospective chart review was
conducted on pediatric patients (aged 60 days to 18 years) diagnosed
with CAP, admitted to a regional, tertiary hospital. Patients were
stratified into two severity cohorts, mild (no ICU care), and moderate
/severe (required ICU care). Biomarker values were then compared between
the severity cohorts and area under the curve (AUC), cut-off values,
performance characteristics were calculated. Results: A total of 108
patients met inclusion criteria. Among the biomarkers examined, elevated
levels of CRP (51.7 mg/L in mild vs. 104.8 mg/L in moderate/severe, p =
0.003, PCT (0.29 ng/ml in mild vs. 4.02 ng/ml in moderate/severe, p =
0.001) and band counts (8% in mild vs. 15% moderate/severe, p = 0.009)
were associated with increased pneumonia severity. In predicting
moderate/severe CAP, PCT had the highest AUC of 0.77 (p = 0.001)
followed by bands AUC of 0.69 (p = 0.009) and CRP AUC of 0.67 (p =
0.003). The cut-off for PCT of 0.55ng/ml had a sensitivity of 83% and a
specificity of 65%. A cut-off level of 53.1 mg/L for CRP had a
sensitivity of 79% and specificity of 52%. A cut off level of 12.5%
bands had a sensitivity of 61% and specificity of 71%. Conclusion:
Biomarkers, in particular PCT, obtained early in hospitalization appear
to perform as predictors for CAP severity in children and may be
beneficial in guiding CAP management