Identifying critically ill children at high risk of acute kidney injury and renal replacement therapy

Abstract

Acute kidney injury (AKI), a common complication in paediatric intensive care units (PICU), is associated with increased morbidity and mortality. In this single centre, prospective, observational cohort study, neutrophil gelatinase-associated lipocalin in urine (uNGAL) and plasma (pNGAL) and renal angina index (RAI), and combinations of these markers, were assessed for their ability to predict severe (stage 2 or 3) AKI in children and young people admitted to PICU. In PICU children and young people had initial and serial uNGAL and pNGAL measurements, RAI calculation on day 1, and collection of clinical data, including serum creatinine measurements. Primary outcomes were severe AKI and renal replacement therapy (RRT). Secondary outcomes were length of stay, hospital acquired infection and mortality. The area under the Receiver Operating Characteristic (ROC) curves and Youden index was used to determine biomarker performance and identify optimum cut-off values. Of 657 children recruited, 104 met criteria for severe AKI (15∙8%) and 47 (7∙2%) required RRT. Severe AKI was associated with increased length of stay, hospital acquired infection, and mortality. The area under the curve (AUC) for severe AKI prediction for Day 1 uNGAL, Day 1 pNGAL and RAI were 0.75 (95% Confidence Interval [CI] 0∙69, 0∙81), 0∙64 (95% CI 0∙56, 0∙72), and 0.73 (95% CI 0∙65, 0∙80) respectively. The optimal combination of measures was RAI and day 1 uNGAL, giving an AUC of 0∙80 for severe AKI prediction (95% CI 0∙71, 0∙88). In this heterogenous PICU cohort, urine or plasma NGAL in isolation had poorer prediction accuracy for severe AKI than in previously reported homogeneous populations. However, when combined together with RAI, they produced good prediction for severe AKI.

The renal angina index accurately predicts low risk of developing severe acute kidney injury among children admitted to a low-resource pediatric intensive care unit

“…In our cohort, RA positivity was 20.5% at baseline, similar to other studies (17.9 to 22.5%) that had enrolled patients with respiratory and post-operative conditions as the indication for PICU admission [ 13 , 29 ]. In contrast, two American studies by Gorga et al.…”

Re-evaluating Renal Angina Index: An Authentic, Evidence-Based Instrument for Acute Kidney Injury Assessment: Critical Appraisal

“…The study showed a sensitivity of 88%, a specificity of 58%, a PPV of 24%, an NPV of 97%, and an AUC of 0.73. However, when the author combined RAI with a biomarker, NGAL, the AUC was 0.80, suggesting a higher association in predicting severe AKI in PICU patients ( 17 ). Similarly, another recent study by Raman et al .…”

Predictive ability of renal angina index alone or in combination with biomarkers for detection of acute kidney injury in children

“…However, in the present meta-analysis by Meena et al [24], combination of urinary NGAL with RAI positivity was found to have better specificity of prediction of severe AKI. Individually plasma NGAL has been found to have lower predictive ability than urinary NGAL and RAI, but in combination with RAI, they have better prediction for severe AKI [28]. Basu et al [29] studied discrimination of plasma NGAL, matrix metalloproteinase-8 (MMP-8) and neutrophil elastase-2 (Ela-2), determined individually and in combination with the RAI for severe AKI in children with sepsis.…”