Endotoxemia in pediatric critical illness - a pilot study

INTRODUCTION: The aim was to investigate the prevalence of endotoxemia in children admitted to pediatric intensive care unit (PICU), and its association with disease severity and outcome. METHODS: We conducted a prospective, observational cohort study of children admitted to PICU at St. Mary's Hospital, London over a 6-month period. One hundred consecutive patients were recruited. Demographic and clinical data were collected. Severity of illness was assessed by the pediatric index of mortality 2 (PIM2) score. The pediatric logistic organ dysfunction (PELOD) score was performed daily for the first 4 days. Patients were categorized according to primary reason for PICU admission. Blood samples were taken within 24 hours of admission and endotoxemia was measured using the endotoxin activity assay (EAA). Patients were stratified according to EAA level (high, EAA > 0.4, low, EAA < 0.4) and categorized as septic, post-surgical, respiratory or other. Data were analyzed using appropriate non-parametric tests. RESULTS: EAA level was significantly lower in PICU controls versus other PICU admissions (P = 0.01). Fifty-five children had endotoxemia on admission. Forty-one (75%) of these were eventually diagnosed with an infectious cause of admission. Nine children without infection had elevated EAA on admission. An infectious cause of admission was significantly associated with endotoxemia (P < 0.005). Of 15 children with gram-negative infection, only 9 (60%) had endotoxemia on admission. Endotoxemia on admission was not associated with shock or death. However, there was a tendency for increased PELOD score and length of stay in endotoxemic children. CONCLUSIONS: Endotoxemia is common in children admitted to intensive care. Understanding the implications of endotoxemia and potential anti-endotoxin strategies may have the potential to reduce severity of illness and length of PICU stay in critically ill children.