Acute non-A, non-B hepatitis in a hospital population in Warsaw, Poland: clinical and epidemiological aspects.

In the years 1986-1988, 530 consecutive cases of acute viral hepatitis were admitted to an infectious disease hospital in Warsaw. Hepatitis A was diagnosed in 34 cases (6.4%), hepatitis B in 436 (82.3%), CMV infection in five (0.9%), and 55 cases (10.4%) were classified as hepatitis non-A, non-B. In 47 cases (85%) of non-A, non-B hepatitis, there was evidence of parenteral transmission, whereas in eight (15%), the source of infection was unknown. Chronic liver disease developed in 50% of patients with parenteral exposure, but there were no cases with known exposure. Seroconversion to anti-HCV was observed only in patients with parenteral exposure, and 60% of followed up cases developed antibodies within 6 months.