Identifying kidney injury via urinary biomarkers after the comprehensive stage II palliation and bidirectional Glenn procedure: a pilot study.

Single ventricle patients undergoing comprehensive stage II palliation have higher incidence of severe acute kidney injury compared to the bidirectional Glenn palliation; however, the optimal method for early detection remains unknown. Several urinary biomarkers are increased in other patient populations with postoperative kidney injury. We explored the kinetics of these biomarkers in this high-risk population.We conducted prospective, observational study of 20 patients with single ventricle physiology who underwent second stage palliation (July 2019-December 2021). Acute kidney injury was defined by Kidney Diseases Improving Global Guidelines, based on peak serum creatinine value and urine output. Urine samples were collected pre-operatively and at 1-, 6-, and 24-hours post-surgery. Urinary biomarkers neutrophil gelatinase-associated lipocalin, interleukin-18, liver fatty acid-binding protein, kidney injury molecule-1, and cystatin C were quantified by enzyme linked immunosorbent assay, normalised to urinary creatinine, and shown as median [interquartile range].Four patients (50%) undergoing comprehensive stage II and 1 patient (8%) undergoing bidirectional Glenn palliation developed stage ≥ 2 acute kidney injury. Comprehensive stage II compared to bidirectional Glenn group had higher median neutrophil gelatinase-associated lipocalin (1769 [1309-1961] versus 91[18-1120] ng/mg) and liver fatty acid-binding protein (12,836 [5016-19798] versus 1272 [220-5172] ng/mg) that peaked 1-hour post-surgery. Kidney injury molecule-1 was significantly greater at 1-, 6-, and 24-hours (greatest) post-surgery in comprehensive stage II than bidirectional Glenn (24h: 11[9-23]) versus 2 [1-6] ng/mg).Elevated urinary neutrophil gelatinase-associated lipocalin, liver fatty acid-binding protein, and kidney injury molecule-1 may be useful biomarkers for early detection of acute kidney injury in children following comprehensive stage II palliation.