Reverse Hepatorenal Index: A New Parameter for Detection of Early Chronic Renal Parenchymal Changes

Aim of the Study: Early detection of chronic kidney disease (CKD) remains a clinical challenge. Current diagnostic parameters often identify renal dysfunction only after significant parenchymal damage has occurred. This study introduces the Reverse Hepatorenal Index (RHI), a novel ultrasound-based parameter designed to detect early chronic renal parenchymal changes and evaluates the diagnostic accuracy of the Reverse Hepatorenal Index in detecting early chronic renal parenchymal changes compared to conventional parameters. Material and Methods: A prospective observational study was conducted on 150 participants (75 with early-stage CKD and 75 healthy controls) from January 2025 to May 2025. Ultrasound examinations were performed to measure renal and hepatic echogenicity. The RHI was calculated as the below normal values of the ratio of hepatic cortical echogenicity to renal cortical echogenicity. Serum creatinine, estimated glomerular filtration rate (eGFR), and urinary biomarkers were measured for comparison. Results: The mean RHI was significantly lower in patients with early CKD (0.78 ± 0.12) compared to healthy controls (1.15 ± 0.09) (p<0.001). RHI demonstrated a sensitivity of 86.7% and specificity of 90.7% for detecting early renal parenchymal changes at a cut-off value of 0.92. The area under the ROC curve for RHI (0.924) was superior to serum creatinine (0.756) and comparable to eGFR (0.889). Conclusion: The Reverse Hepatorenal Index represents a promising non-invasive parameter for early detection of chronic renal parenchymal changes. Its superior performance compared to traditional markers suggests potential clinical utility in CKD screening and monitoring.