Table 1.

Main biomarkers in pediatric sepsis

Biomarker	Why use?	Limitations
CRP	Easily available and low cost Peaks 36 - 50 hours after an inflammatory trigger Serial use for therapeutic response assessment Not affected by immunosuppression, renal dysfunction or corticosteroid use	Variable sensitivity and specificity for detecting bacterial infection (lower when a single measurement is performed) Low accuracy
PCT	Peaks 24 - 36 hours after an inflammatory trigger More specific for bacterial infection	Variable sensitivity and specificity Altered serum levels in cases of renal dysfunction Lack of multicenter and prognostic and risk stratification studies Higher cost
IL-6 and IL-8	Increased accuracy when combined with other biomarkers Good correlation with severity Promising use in pediatric patients with cancer and febrile neutropenia	Few studies in the pediatric population
Adrenomedullin (proADM)	Correlation with severity and potential use as a risk stratifier Promising marker of diagnosis of infection in febrile neutropenic patients	Studies in the pediatric population are still scarce Not yet available for use in clinical practice
NGAL	Promising biomarker of acute kidney injury (organ dysfunction) Early increase in cases of acute kidney failure (48 hours prior to the increase of creatinine) Early introduction of renal protection measures	Lacks validation in pediatric patients with septic shock (low specificity as a kidney injury predictor) Low availability for use in clinical practice

CRP - C-reactive protein; PCT - procalcitonin; IL-6 - interleukin 6; IL-8 - interleukin 8; NGAL - human neutrophil gelatinase.