Acute posttransfusion hepatitis C: identification of a common hepatitis C virus strain in donor and recipient using polymorphism analysis.

An 11-year-old Thai boy who had received multiple blood transfusions from 12 different donors for treatment of Dengue shock syndrome presented with symptoms of acute hepatitis 5 weeks thereafter. He was found positive for antibodies to hepatitis C virus (HCV) and HCV-RNA was detected by reverse transcription PCR (RT-PCR). When his alanine aminotransferase (ALT) level peaked at 1,879 U/l in the 8th week, interferon therapy (3 million units, thrice weekly for 6 months ) was initiated. After initially decreasing to tenfold the normal level, the ALT dropped to fivefold the normal level at 6 months. HCV RNA is still detectable in his serum 6 months later. Using RT-PCR and subsequent restriction fragment length polymorphism (RFLP) analysis we identified one of the donors as harboring HCV genotype 3a, identical to that found in the patient. Moreover, polymorphism analysis on the hypervariable region employing five distinct restriction endonucleases suggested this donor as the source of infection. We hence recommend thorough screening of all blood donors as the only means of prevention presently feasible.