[Mutations within the interferon sensitivity determining region in Korean patients infected with hepatitis C virus genotype 1b].

BACKGROUND/AIMS: The treatment response to interferon could differ with mutations in the interferon-sensitivity-determining region (ISDR) in patients infected with hepatitis C virus (HCV) genotype-1b (HCV-Ib). We examined the pattern of ISDR mutations and analyzed whether the number of amino acid substitutions influences the treatment response to peginterferon plus ribavirin in chronic hepatitis or cirrhotic patients infected with HCV-Ib. METHODS: The study population comprised 52 patients who visited Seoul Asan Medical Center and Seoul National University Bundang Hospital from January 2006 to December 2008 and who received peginterferon alpha-2a (n=37) or -2b (n=15) plus ribavirin, and whose serum was stored. We analyzed the early virologic response, end-of-treatment response, and sustained virologic response (SVR), and examined the ISDR using direct sequencing. RESULTS: The proportions of patients with ISDR mutation types of wild (0 mutations), intermediate (1-3 mutations), and mutant (> or =4 mutations) were 50.0%, 42.3%, and 7.7%, respectively, and the corresponding SVR rates were 63%, 50%, and 67% (p>0.05). The SVR rates were 59.4% and 50.0% in patients with <2 and > or =2 mutations, respectively (p>0.05). On univariate analysis, age was the only predictive factor for SVR (p=0.016). The pretreatment HCV RNA titer tended to be lower in those with SVR, but without statistical significance (p=0.069). CONCLUSIONS: The frequency of ISDR mutations was low in our cohort of Korean patients infected with HCV-Ib. Therefore, ISDR mutations might not contribute to the response to treatment with peginterferon plus ribavirin.

[Nine cases of sporadic acute hepatitis E in Korea].

Hepatitis E virus is an enterically transmitted virus that causes endemic cases of acute hepatitis in many countries in Africa, and Southeast and Central Asia. Sporadic cases of acute hepatitis E also have been reported in developed countries. In non-endemic areas, most of the sporadic cases of hepatitis E are introduced from the endemic areas. Until now, only three cases of acute hepatitis E have been reported in Korea. Recently, we experienced nine cases of acute hepatitis, in which serologic studies showed positive of IgM anti-HEV. We report these as cases of acute hepatitis E. These cases suggest that HEV infection occurs sporadically in Korea and should be considered as a cause of cryptogenic acute hepatitis.