Hyperglycemia and acute kidney injury in critically ill children

BACKGROUND Hyperglycemia and acute kidney injury (AKI) are common in critically ill children and have been associated with higher morbidity and mortality. The incidence of AKI in children is difficult to estimate because of the lack of a standard definition for AKI. The pediatric RIFLE (Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease) criteria can be used to define AKI in children. Various biomarkers in urine and blood have been studied to detect AKI in critically ill children. However, it is not clear whether hyperglycemia is associated with AKI. Our objective was to evaluate the effect of hyperglycemia on kidney function and its effect on neutrophil gelatinase-associated lipocalin (NGAL) in children. METHODS We studied retrospective and prospective cohorts of pediatric critically ill subjects admitted to the pediatric intensive care unit (PICU). We analyzed data from admission that included estimated glomerular filtration rate, plasma and urine NGAL, serum glucose and peak glycemia (highest glycemia during PICU admission), and length of hospital and PICU stay from two different institutions. RESULTS We found that the prevalence of hyperglycemia was 89% in the retrospective cohort and 86% in the prospective cohort, P=0.99. AKI was associated with peak glycemia, P=0.03. There was a statistically significant correlation between peak glycemia and hospital and PICU stays, P=<0.001 and P<0.001, respectively. Urine NGAL and plasma NGAL were not statistically different in subjects with and without hyperglycemia, P=0.99 and P=0.85, respectively. Subjects on vasopressors had lower estimated glomerular filtration rate and higher glycemia, P=0.01 and P=0.04, respectively. CONCLUSION We conclude that in critically ill children, hyperglycemia is associated with AKI and longer PICU stays.