[Delta hepatitis: Epidemiology, diagnostic, natural history and treatment]

Hepatitis B virus is a small enveloped RNA virus, which replicates independently but requires the hepatitis B virus (HBV) to provide the envelope proteins necessary for the assembly of its own viral particles. Approximately 5% of chronic hepatitis B virus carriers are infected with HDV. HBV vaccination remains the best preventive treatment for HDV. All HBV patients should be screened for HDV (anti-HDV serology). In case of positive HDV serology, HDV replication (HDV RNA) should be investigated using a sensitive and specific technique. Hepatitis Delta is often complicated by cirrhosis and hepatocellular carcinoma (HCC). For this reason, every patient with Delta cirrhosis should be screened for HCC by abdominal ultrasound every 6 months. The historical treatment was based on PEG-IFN with many side effects. A new treatment has been approved, Bulevirtide (Hepcludex®) an HDV/HBV entry inhibitor, for any patient with chronic hepatitis Delta infection (CHD) with active replication (except in decompensated cirrhosis), at a dose of 2mg/day by subcutaneous injection. The exact duration on-treatment is unknown, thus treatment should be continued if clinical benefit is observed.