NATURAL-HISTORY OF HEPATITIS-C

Hepatitis C is becoming the main cause of cirrhosis and primary liver carcinoma. Infection by hepatitis C virus (HCV) generally induces an a symptomatic acute hepatitis. HCV infection becomes chronic in about 80 % of cases. In a minority of the subjects, chronic HCV infection is a symptomatic with persistent viremia and normal liver tests. These asym ptomatic subjects have minimal liver histologic lesions and a good pro gnosis. In a majority of the subjects, chronic HCV infection is associ ated with chronic hepatitis with increased serum transaminases levels. Among the patients with chronic hepatitis, the majority have a mild l iver disease with a moderate increase in serum transaminases levels an d, at liver histology, minimal lesions; a minority (about 20 %) have a more severe liver disease and will develop cirrhosis after 5 to 20 ye ars. In patients with HCV related cirrhosis, the incidence of hepatoce llular carcinoma is high (around 5 % per year). The factors influencin g the evolution of HCV infection are not known. Alcohol is certainly a n important factor which increases the risk of development of fibrosis then cirrhosis. Virus related factors, such as genotype and level of replication, might also be important. Autoimmune diseases have been re ported in association with hepatitis C. HCV infection is a major cause of mixed cryoglobulinemia associated with vasculitis or glomeruloneph ritis. A relationship between HCV and auto-immune diseases such as thy roiditis or Gougerot syndrome has been suggested but not demonstrated. HCV infection is frequent in patients with porphyria cutanea tarda; i n these patients, HCV related liver disease might trigger the expressi on of the metabolic disease.