Peripheral Biomarkers in Chronic Hepatitis D Infection: A Review

Chronic hepatitis D represents the most severe form of viral hepatitis and is associated with higher rates of advanced fibrosis, cirrhosis and hepatocellular carcinoma than hepatitis B monoinfection. It is caused by the hepatitis D virus (HDV), a defective RNA virus that requires co-infection with hepatitis B (HBV) for hepatocyte entry and propagation. Accurate prediction of liver disease sequelae and treatment response using currently available serological biomarkers remains challenging. This article reviews peripheral biomarkers in HDV, including novel biomarkers of HBV activity, exploring their potential clinical utility and areas for future development. Peripheral biomarkers capable of risk stratifying patients with HDV, monitoring or predicting treatment response and elucidating the natural history of infection (including the complex relationship with HBV), would enable individualised care and early identification of those at greater risk of developing advanced liver disease. Establishing the role of these biomarkers in larger, ethnically diverse populations both on existing treatments and in the context of emerging antiviral therapies will be imperative going forward.