Intrarenal Resistive Index and Serum Creatinine in Decompensated Chronic Liver Disease: Implications for Early Prediction of Hepatorenal Syndrome

Abstract

Abstract Background and Objectives: Hepatorenal syndrome (HRS) is a life-threatening complication of decompensated chronic liver disease (DCLD) driven by profound intrarenal vasoconstriction. Serum creatinine is a poor renal marker in cirrhosis because of sarcopenia, increased tubular secretion, and bilirubin-related assay interference. The intrarenal resistive index (RI), obtained by color Doppler ultrasonography, quantifies renal vascular resistance and may detect haemodynamic compromise before creatinine rises. This study assessed the correlation of RI with creatinine, estimated glomerular filtration rate (eGFR) and Child–Turcotte–Pugh (CTP) class, and examined RI distribution across grades of ascites severity. Methods: A cross-sectional study of 100 consecutive adults with DCLD was conducted at a tertiary hospital in Bengaluru (March 2024–August 2025), excluding patients with primary chronic kidney disease (CKD) or nonhepatic acute kidney injury. Creatinine was measured by the kinetic Jaffé method, and eGFR was calculated using the 2021 CKD-Epidemiology Collaboration equation. RI was measured by colour Doppler (3–5 MHz) at the arcuate/interlobar arteries, and the midpoint value was used. Ascites was graded as mild, moderate, or gross per the International Club of Ascites criteria. Pearson/Spearman correlations and analysis of variance were done with Python 3.1 using the pandas (v2.2.2) and SciPy (v1.13.1) libraries. Results: Mean RI was 0.688 ± 0.062, with 38% of patients showing an elevated RI (≥0.70). A moderate positive correlation was seen between RI and creatinine ( r = 0.351, P < 0.001), and an inverse correlation between RI and eGFR ( r = −0.331, P < 0.001), alongside a strong RI–CTP association (ρ = 0.501, P < 0.001). The prevalence of elevated RI increased with ascites severity: 11.6% in mild, 52.0% in moderate, and 62.5% in gross ascites ( P < 0.001). Conclusion: RI is associated with markers of both renal function and the severity of decompensation in DCLD. Its steady rise with worsening ascites supports the use of bedside Doppler as a practical adjunct for identifying patients at risk of HRS early, particularly those with moderate or gross ascites.