Diagnostic utility of urine neutrophil gelatinase-associated lipocalin and renal resistive index in patients of decompensated cirrhosis with acute kidney injury

Abstract

Background: The differentiation between types of acute kidney injury(AKI) in decompensated cirrhosis(DC) patients in clinical practice is done by clinical adjudication. Biomarkers have good diagnostic accuracy for predicting acute tubular necrosis(ATN), however they are not available routinely.

Aims: We compared the diagnostic accuracy of urine neutrophil gelatinase-associated lipocalin(UNGAL) and renal resistive index(RRI) in predicting type of AKI among DC patients.

Methods: Consecutive DC patients with AKI stage≥1B seen between June/2020 to May/2021 were evaluated. UNGAL levels and RRI were measured at diagnosis of AKI(Day 0) and 48hrs(Day 3) after volume expansion. Diagnostic accuracy of UGNAL and RRI was compared for differentiating ATN and non-ATN AKI by area under receiver operating characteristic curve(AUROC), using clinical adjudication as gold standard.

Results: 388 DC patients were screened, 86 patients(Pre-renal AKI[PRA] n=47,55%; Hepatorenal syndrome[HRS] n=25,29%;ATN n= 14,16%) were included. The AUROC of UNGAL for differentiating ATN-AKI and non-ATN AKI at day 0 was 0.97(95%CI, 0.95-1.0) and on day 3 was 0.97(95%CI, 0.94-1.0). The AUROC of RRI for differentiating ATN and non-ATN AKI at day 0 was 0.68(95%CI, 0.55-0.80) and on day 3 was 0.74(95%CI, 0.63-0.84).

Conclusion: UNGAL has an excellent diagnostic accuracy in predicting ATN-AKI in DC patients both at day 0 and 3.

Keywords: Acute kidney injury; Cirrhosis; Neutrophil gelatinase-associated lipocalin; Renal resistive index.