Urinary Neutrophil Gelatinase-Associated Lipocalin Does Not Distinguish Acute Rejection from Other Causes of Acute Kidney Injury in Pediatric Renal Transplant Recipients

Abstract The aim of this prospective single center study was to investigate the ability of urinary neutrophil gelatinase-associated lipocalin (NGAL) to distinguish acute rejection from other causes of acute kidney injury (AKI) in children after renal transplantation. Fifteen children fulfilled the inclusion criteria (acute kidney injury (AKI) with allograft biopsy, at least 21 days after renal transplantation, no sepsis) during 2013 - 2014 in our pediatric transplantation center. The mean age was 14.8  2.8, median time after renal transplantation was 0.4 years (range 0.1 - 3.8). Urinary NGAL was measured in spot urine by Chemiluminescent Microparticle Immunoassay technology. Four patients had biopsy proven acute rejection (rejection group), eleven children had AKI of other cause (non-rejection group). The median urinary NGAL concentration in the rejection group was not significantly different from NGAL in the non-rejection group (7.3 ng/mL, range 3.0 - 42.3 vs. 8.6 ng/mL, range 3.4 - 54.7, p = 0.48). There was a significant negative correlation between eGFR and urinary NGAL concentrations (r = -0.77, p