[Hepatitis C]. / Hépatite C.

ABSTRACT

Hepatitis C is usually poorly symptomatic, particularly in the acute phase. After an incubation period ranging from 5 to 12 weeks, the symptoms are nonspecific and icterus is rarely present. Laboratory results are more suggestive, showing characteristic fluctuations in transaminases comprising periods with normal values. Chronic hepatitis is probable when elevation of transaminases persists for more than 6 months. Chronic virus C hepatitis is usually asymptomatic. Clinical manifestations are poorly specific and transaminase concentrations are generally little increased and variable in over 75% of the cases. Some histological lesions are more often observed in the chronic stage, particularly steatosis, presence of intraportal lymphoid nodules and bile duct involvement. The natural history is dominated by the risk of development to cirrhosis and hepatocellular carcinoma. A course to chronic hepatitis C is observed in 20 to 70% of cases, while the risk of developing cirrhosis is between 10 and 38% within approximately 20 years. Prognosis is then linked to decompensation of cirrhosis and especially to the development of hepatocellular carcinoma, within approximately 10 years after appearance of cirrhosis, with a prevalence of at least 20%. The association of other factors such a hepatitis B virus or alcohol can accelerate this course.