Hepatitis C Virus Genotype and the Natural History of HIV-1 Disease: Potential Role of GB Virus C in the Hemophiliac Population

    Department of Internal Medicine, Michigan State University College of Human Medicine, East Lansing

    Yoo et al. [1] recently reported that, in individuals coinfected with HIV-1 and hepatitis C virus (HCV), infection with HCV genotype 1 was associated with an increased risk for progression to AIDS-related mortality. Their study suggested that HIV-1infected individuals with HCV genotype 1 infection had higher HCV RNA levels and lower absolute CD4+ T cell counts than did those without HCV genotype 1 infection. Whether this observation is a direct effect of HCV genotype 1 infection or the result of a confounding factor is a question that needs to be further explored. A possible confounding factor may be the status of GB virus C (GBV) infection in these individuals. This RNA virus has been found in hemophiliacs [2], and the common routes of exposure to both HIV-1 and GBV suggest that coinfection with the 2 viruses may be common; such coinfection has been noted especially frequently in hemophiliacs with HIV-1 infection [3], but it has also been noted in patients with other modes of acquisition of HIV-1 [4].

    There have been multiple recent reports suggesting that, in patients coinfected with HIV-1 and hepatitis G, progression of HIV-1 infection may be delayed [37]. Differences in GBV infection status among the subjects in the Yoo et al. study might partly explain the differential CD4+ T cell counts noted in individuals with HCV genotype 1. It would be of interest to know whether the authors explored this possibility.

    References

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