Prediction of Hepatic Fibrosis in Patients With Chronic Hepatitis C by Biochemical and Duplex Doppler Indices

Chronic hepatitis C virus (HCV) infection is a global health problem, affecting about 3% of the world's population. Compared to patients with mild hepatic fibrosis, those with significant fibrosis are at risk of developing cirrhosis over a 10- to 20-year period. This fact suggests the need of early antiviral therapy in chronic hepatitis C (CHC) patients to prevent the development of cirrhosis and associated complications. For patients having cirrhosis, surveillance endoscopy and ultrasound for gastroesophageal varices and hepatocellular carcinoma are needed to minimize morbidity and mortality ). Furthermore, reduced treatment response and tolerability to antiviral therapy may be encountered in cirrhotic patients. An accurate assessment of hepatic fibrosis stage is therefore important for both diagnostic and therapeutic purposes.

Liver biopsy has been recognized as the gold standard for assessing the grade of necroinflammation and stage of fibrosis. However, it is costly, and harbors risk of complications, including 20% of patient discomfort, 0.1-3% of significant morbidity, and 0.02-0.24% of mortality. In addition, sampling error due to the non-uniform distribution of the parenchymal damage, as well as intra- and inter-observer variability is often encountered. A noninvasive tool to evaluate liver disease activity or fibrosis stage would be helpful, particularly in monitoring CHC patients over time.

Noninvasive methods to evaluate the hepatic histology in HCV-infected patients include symptoms and signs, routine laboratory tests, serum markers of fibrosis and inflammation, quantitative tests of liver function, and radiological imaging. Previous studies have assessed the usefulness of noninvasive tests in predicting hepatic fibrosis. However, none of them showed satisfactory results, either due to lack of accuracy, accessibility, reproducibility or being expensive.

Duplex Doppler ultrasonography (DDU), which is readily available and non-invasive, has been used for the assessment of splanchnic vascular hemodynamics in patients with chronic liver disease. Portal vein velocity (PVV) has been shown to be correlated with significant fibrosis or cirrhosis. Hepatic artery resistive index (HARI) and pulsatility index (HAPI) are associated with portal vein resistance and hepatic vein-portal vein pressure gradient (HPVG). Splenic artery resistive index (SARI) and pulsatility index (SAPI) are associated with portal vein resistance, cirrhosis and grade of esophageal varices (EV). Previous studies to evaluate the value of DDU in predicting liver histology are controversial, probably due to small patient number, diverse grading of liver histology, and large missing data.

Thus, the purpose of our prospective study was to evaluate the value of Doppler parameters and compare the diagnostic accuracy of Doppler parameters with various biochemical indices in predicting significant hepatic fibrosis (≥ F2) and cirrhosis (F4) in chronic hepatitis C (CHC) patients.