[Chronic viral hepatitis: current diagnosis and therapy].

Viral infections are major causes of chronic liver diseases. The etiologic agents are hepatitis B virus (HBV), the HBV-associated hepatitis delta virus (HDV) and hepatitis C (HCV). In general, these viral infections can be specifically identified by serological tests and molecular techniques. The identification of the causative agents is clinically relevant both for epidemiologic-preventive and therapeutic considerations. The therapy of choice for chronic viral hepatitis B or C is interferon-alfa (10 mill units 3x per week for about 6 months). The long-term response rate is 30 to 40% for chronic hepatitis B and 20 to 30% for chronic hepatitis C. The results for chronic hepatitis D are controversial at present. Based on these results, therapeutic strategies have to be modified and improved further. Apart from therapeutic considerations, measures to prevent viral hepatitides should be carefully implemented (HBV vaccination of individuals at risk, reduction of blood transfusions, general hygienic measures), in order to reduce the morbidity and mortality from acute and chronic hepatitis, including liver cirrhosis and hepatocellular carcinoma.