GB virus C (GBV-C) infection in hepatitis C virus (HCV)/HIV-coinfected patients receiving HCV treatment: importance of the GBV-C genotype.

BACKGROUND: Persistent GB virus C (GBV-C) coinfection leads to slower human immunodeficiency virus (HIV) progression. Despite the existence of multiple GBV-C genotypes, their relevance to the progression of HIV disease is unknown. We therefore investigated (1) the prevalence and genotype of GBV-C in hepatitis C virus (HCV)/HIV-coinfected patients and (2) the impact of HCV treatment on GBV-C RNA clearance.
METHODS: We retrospectively studied 130 HCV/HIV-coinfected patients initiating HCV therapy. Anti-E2 enzyme-linked immunosorbent assay, reverse-transcription polymerase chain reaction (PCR), and real-time PCR were used to detect and quantify GBV-C infection. GBV-C genotype was determined by sequencing the 5' untranslated region.
RESULTS: GBV-C infection (past or current) was identified in 111 (85%) of the patients. Ongoing GBV-C replication was detected in 40 patients. Coinfection with GBV-C genotype 2 was associated with significantly higher CD4(+) cell counts. After 24 weeks of HCV therapy, GBV-C RNA clearance was observed in 50% of patients, although this was not associated with changes in HIV load or with CD4(+) cell counts. Sustained GBV-C RNA clearance was observed in 31% of patients with GBV-C RNA detected at baseline.
CONCLUSIONS: GBV-C coinfection was extremely common. GBV-C RNA clearance with HCV therapy was associated with neither short-term loss of HIV control nor impaired immune status. The association of GBV-C genotype 2 with higher CD4(+) cell counts merits further study.