Urinary neutrophil gelatinase‐associated lipocalin determines short‐term mortality and type of acute kidney injury in cirrhosis

BACKGROUND AND AIM: Acute kidney injury increases mortality in cirrhotic patients by four fold. This study aimed to determine the usefulness of urinary neutrophil gelatinase‐associated lipocalin (uNGAL) for differential diagnosis for acute kidney injury and for predicting short‐term mortality in cirrhotic patients. METHODS: We enrolled 94 patients of decompensated cirrhosis. uNGAL was measured upon hospital admission in all patients. Patients with urinary tract infection and anuria were excluded. Patients were followed for 30 days or until death. RESULTS: Ten (9%) patients had normal kidney function, 9 (11.37%) stable chronic kidney disease, 32 (29.50%) prerenal azotemia, 33 (36.37%) hepatorenal syndrome (HRS), and 10 (13.64%) intrinsic acute kidney injury (iAKI). Prerenal azotemia had lower median uNGAL values compared to HRS and iAKI (95.50 vs 465.00 vs 1217.50, P < 0.001). uNGAL levels were significantly higher in patients who died within 30 days (717.17 ± 494.26 vs 331.65 ± 313.65 ng/mL, P −0.0017). On univariate analysis, serum creatinine (sCr), uNGAL, Model for End‐Stage Liver Disease (MELD) score on admission, and length of stay were significant, and on multivariate analysis, uNGAL and hepatic encephalopathy (HE) were significant in predicting mortality. CONCLUSIONS: uNGAL at baseline serves as an early marker in differentiating HRS, prerenal AKI, and iAKI in cirrhotic patients, where sCr values are not useful. Patients with higher uNGAL levels had higher transplant‐free mortality at 30 days.