2000 年 191 巻 4 号 p. 247-253
A 27-year-old man who had been diagnosed as having chronic hepatitis B suffered disease exacerbation with marked reactivation of hepatitis B virus (HBV). Treatment with interferon (IFN) did not improve his condition, and his serum HBV DNA level increased to over 10 000 pg/ml during IFN administration. Following replacement with lamivudine, there was a substantial reduction in HBV DNA to an undetectable level, and liver function parameters subsequently improved to within the normal range. Quantitative analysis of the precore mutant HBV DNA, which is a variant that cannot express hepatitis B e antigen due to a G-to-A point mutation in the precore region of the viral genome, revealed that the amount present was greater than for the precore wild-type HBV DNA in the serum taken before IFN treatment. This case suggests that lamivudine would be an appropriate alternative to IFN, particularly in patients infected with HBV containing an excess of precore mutants resistant to IFN therapy.