[Chronic viral hepatitis: diagnosis and treatment].

HBV and HCV cause most of chronic hepatitis; the HDV is a co-infectious virus and it rend the help of HBV to duplicate; HAV and HEV do not induce chronic hepatitis. Etiology is not the same, without apparent reasons, in all the world and the distinction between persistent chronic hepatitis and active idiopathic chronic hepatitis is meaningless, because one can shift in the other. Diagnosis is possible using serologic tests and by determination of the DNA of the HBV and RNA of the HCV. Interferon is a good therapeutic tool either for B hepatitis than for C hepatitis in about 50% of case. On the contrary, the results obtained with liver transplantation are disappointing and those achieved with ribavirin have not been conclusive yet. The treatment with INF for more than one year and with full dosages, gives good results in about 50% of patients with hepatitis D. In the other patients it is not useful a second cycle with INF or the introduction of pure antiviral drugs alone or in association with INF.