Circulating NGAL as a multipurpose biomarker in patients hospitalized for acute decompensation of cirrhosis.

There is limited evidence regarding the role of circulating neutrophil gelatinase-associated lipocalin (NGAL) in patients admitted with complications of cirrhosis. This prospective cohort study evaluated 161 adult patients hospitalized for acute decompensation (AD) of cirrhosis, with serum samples collected within 48 h of admission. The aim was to investigate the association between NGAL levels, acute kidney injury (AKI), and patient outcomes. Sixty patients presented with AKI at admission. Serum NGAL was independently associated with AKI (OR 1.019, 95% CI 1.012-1.027; p < 0.001), with levels increasing across AKI stages: no AKI (94.24 µg/L), stage 1 (179.20 µg/L), stage 2 (235.50 µg/L), and stage 3 (257.85 µg/L; p < 0.001). Hepatorenal syndrome (HRS) was associated with significantly higher NGAL compared to pre-renal AKI (259.70 vs. 179.30 µg/L; p = 0.002). NGAL predicted HRS with an AUROC of 0.837 (±0.064), with a negative predictive value of 94% for NGAL < 215.00 µg/L. It also predicted AKI reversibility, with an AUROC of 0.829 (±0.061) and a positive predictive value of 98% for NGAL < 242.00 µg/L. Furthermore, NGAL independently predicted 30-day mortality, with a survival probability of 90.8% for NGAL < 160 µg/L and 66.7% for NGAL ≥ 160 µg/L (p < 0.001). These findings support the clinical utility of circulating NGAL as a biomarker reflecting AKI phenotype and disease severity in patients acutely hospitalized for cirrhosis-related complications, with prognostic relevance.