Histological patterns of prolonged hepatitis C infection.

Liver biopsies from 63 patients with hepatitis C virus (HCV) infection have been studied. 31 were asymptomatic and had been detected by a variety of screening programs, and most of the other 32 had complained of vague symptoms only. In 57 patients a confident estimate of the duration of infection was able to be made (ranging from 12 months to over 38 years) and 73% of these had been infected for over 5 years. The most common histological pattern observed was a low-grade panacinar hepatitis. This affected 74.6% of all biopsies, and 43% of this group had been infected for over 10 years. Severe chronic active hepatitis and/or cirrhosis occurred in only 8% of the whole series, and in 16.7% of those infected for over 10 years. This incidence of serious sequelae in chronic HCV infection is much lower than previously reported, probably reflecting the methods of patient selection, and may represent more accurately the natural history of the disease in this community. The occurrence of a number of characteristic histological features (lymphoid follicles and aggregates, steatosis, Kupffer cell prominence, and apoptotic or acidophilic bodies) was confirmed, the constellation of which is highly suggestive of HCV infection. It is suggested that apoptosis may play an important role in the perpetuation of HCV as a chronic infection.