Urinary biomarkers as indicators of acute kidney injury in critically ill children exposed to vancomycin

Abstract

IntroductionThe standard of care for detecting acute kidney injury (AKI) is change in serum creatinine (SCr) and urine output, which are limited. This study aimed to compare urinary biomarkers neutrophil gelatinase‐associated lipocalin (uNGAL) with kidney injury molecule‐1 (uKIM‐1) in critically ill children exposed to vancomycin who did and did not develop AKI as defined by changes in SCr.MethodsThis was a single‐center, prospective, clinical, observational cohort study at a large tertiary care children's hospital in an urban setting. Children aged 0 (corrected gestational age 42 weeks) to 18 years admitted to the intensive care unit who received vancomycin were included. The primary outcome was mean change in uNGAL and uKIM‐1 between AKI and no‐AKI groups. AKI was defined as a minimum 50% increase in SCr from baseline over a 48‐hour period, within 7 days of first vancomycin exposure. Three urine samples were collected: baseline (between 0 and 6 hours of first vancomycin dose), second (18‐24 hours after the ‘baseline’) and third (18‐24 hours after the second sample). Concentrations of uKIM‐1 and uNGAL were measured in each sample.ResultsForty‐eight children (52% male; median age 6 years) were included. Eight (16.7%) children developed AKI. Mean changes in uNGAL (713196±1216474 vs. 16101±37812 pg/ml; p=0.0004) and uKIM‐1 (6060±11165 vs. 340±542 pg/ml; p=0.0015) were greater in children with AKI vs. no‐AKI, respectively.ConclusionsuNGAL and uKIM‐1 concentrations increased significantly more in critically ill children with AKI compared with those with no‐AKI during the first 48‐72 hours of vancomycin exposure and may be useful as prospective biomarkers of AKI.