Diagnostic accuracy of B-Mode ultrasound and Hepatorenal Index for graduation of hepatic steatosis in patients with chronic liver disease

The aim of our study was to evaluate the diagnostic accuracy of B-Mode ultrasound and Hepatorenal Index (HRI) by high-end devices for the detection and classification of hepatic steatosis in patients with various causes of chronic liver disease (CLD). We retrospectively enrolled patients with CLD who underwent liver biopsy and baseline ultrasound between March 2016 and May 2019. Sonographic graduation of steatosis (0°-III°) using B-Mode criteria and HRI were correlated with the histological graduation (S0 (33-66%) and S3 (>66%). Interobserver agreement was calculated. 157 patients were evaluated. B-Mode ultrasound had a sensitivity of 75.6% and a specificity of 76.0% to differentiate between steatosis and no steatosis (AUROC 0.758). Using B-Mode criteria for advanced steatosis (≥II°), specificity for presence of histological steatosis was ≥98.7%. For detection of advanced steatosis (≥S2), sensitivity of B-mode criteria was 90.9%. In a subgroup of patients with advanced liver fibrosis, sensitivity of B-mode criteria was 95.0% for detection of advanced steatosis (S≥2). A HRI cut-off-value of 1.46 differentiates between patients with steatosis and patients without steatosis with a sensitivity of 42.7% and a specificity of 90.7% (AUROC 0.680). Interobserver agreement of both B-Mode and HRI was good to excellent. B-Mode ultrasound using high-end devices is an excellent method to detect advanced steatosis in patients with various CLD. For diagnosis of mild steatosis, modern ultrasound devices may have higher sensitivity but at the expense of specificity. Stage of fibrosis and etiology of CLD seem not to impact on diagnostic accuracy. The additional calculation of HRI seems to have no additional benefit with regard to detect or grade hepatic steatosis in our study population.