Abstract: Objective The purpose of this study was to investigate the diagnosticefficacy of serum cystatin C (Cys-C), model for end-stage liver disease (MELD) and albumin-bilirubin (ALBI) score combination for hepatorenal syndrome-acute kidney injury (HRS-AKI) in patients with decompendated liver cirrhosis (DLC). Methods 99 patients with HRS-AKI and 117 hospitalized patients with DLC were encountered in our hospital between October 2020 and April 2025, baseline clinical materials,serum biochemical index and serum Cys-C levels were collectedby retrieving our hospital information management (HIS) system, and MELD and ALBI scores were calculated. Binary Logistic regression analysis was appliedto identify factors influencing the occurrence of HRS-AKI, and receiver operating characteristic (ROC) curves were employed to evaluate the diagnostic efficacy for HRS-AKI. Results Serum Cys-C levels, MELD and ALBI scores in patients with HRS-AKI were 2.4 (1.6, 3.3) mg/L, 19.9 (11.8, 24.3) and -1.1 (-1.5, -0.6), all significantly higher than [1.1 (0.9, 1.4) mg/L, 10.9 (7.4, 14.5) and -1.4 (-1.5, -0.9), respectively, P<0.05] in the cirrhosis group; Logistic regression analysis revealed that prothrombin time was a protective factor against HRS-AKI in patients with DLC (OR = 0.852, 95% CI = 0.752-0.964, P<0.05), while serum Cys-C level (OR = 42.318, 95% CI = 13.179-135.888, P<0.05), MELD score (OR = 25.539, 95% CI = 4.266-152.892, P<0.05) and concurrent hepatic encephalopathy (OR = 4.527, 95% CI = 1.283-15.969, P<0.05) were the independent risk factors; ROC analysis showed that the AUC was 0.918 (95% CI: 0.877-0.959), when combination of serum Cys-C level, MELD and ALBI score was set for diagnosing HRS-AKI. Conclusion Serum Cys-C levels in combination with MELD and ALBI scores could assist clinicians for the early diagnosis of HRS-AKI in hospitalized patientswith DLC, which warrants further study.

Key words: Liver cirrhosis, Hepatorenal syndrome, Cystatin C, Model for end-stage liver disease, Albumin-bilirubin score, Diagnosis