Hepatocellular enzyme patterns and hepatitis B virus exposure in multitransfused young and very young hemophilia patients.

Thirty-eight children with severe hemophilia A, 11 years of age and under, were evaluated by initial and follow-up liver function tests (LFTs) in relation to age of onset of transfusion therapy. Each child had at least two complete evaluations within one year for a follow-up period of at least one year. The mean number of exposure days was 36 with a mean of 275 units of factor VIII per exposure day prior to initial LFTs. At initial testing, 30% of patients demonstrated antibody to HBsAg and 39--51% at least one abnormal serum enzyme level (AST, ALT, LDH). During an average follow-up period of 34.8 months, two children developed HBsAg-positive icteric hepatitis. Of those initially serologically negative for HBsAg or antibody, 44% became antibody-positive. Intermittent abnormalities of at least one serum enzyme were observed in 79% of the patient group, with 13% and 8% being persistently normal and abnormal. Eleven children born after January 1976, receiving only third-generation RIA-tested products for HBsAg, constituted a subgroup. Although only one child at first assessment had evidence of hepatitis B virus exposure, 55% had elevated ALTs, indicating considerable frequency of non-A, non-B hepatitis in this very young group.