Improved Risk Stratification in Pediatric Septic Shock Using Both Protein and mRNA Biomarkers. PERSEVERE-XP

Rationale: We previously derived and validated the Pediatric Sepsis Biomarker Risk Model ( PERSEVERE) to estimate baseline mortality risk in children with septic shock. The PERSEVEREbiomarkers are serum proteins selectedfrom among the proteins directly related to 80 mortality risk assessment genes. The initial approach to selecting the PERSEVEREbiomarkers left 68 genes unconsidered.Objectives: To determine if the 68 previously unconsidered genes can improve upon the performance of PERSEVEREand to provide biological information regarding the pathophysiology of septic shock.Methods: We reduced the number of variables by determining the biological linkage of the 68 previously unconsidered genes. The genes identified through variable reduction were combined with the PERSEVERE-based mortality probability to derive a risk stratification model for 28-day mortality using classification and regression tree methodology (n = 307). The derived tree, PERSEVERE-XP, was then tested in a separate cohort (n = 77).Measu...