Prevalence and genotypic variability of TTV in HIV-infected patients

TT virus is a small, circular DNA virus, that has been associated with transfusion hepatitis. We sought to determine the prevalence of TT virus (TTV) in patients with human immunodeficiency virus (HIV) infection and to characterize the virus in terms of genotypic variability and in the relationship to CD4+, HIV viral loads, HCV/HIV coinfection, and ALT abnormalities. A cross-sectional analysis of HIV-infected patients in the United States, including 86 HIV-positive subjects and 118 HIV-negative controls was performed. TTV was detected using a seminested PCR technique. Samples underwent cloning and sequence analysis and/or RFLP to determine genotype. Thirty-eight percent of HIV-positive patients had TTV infection versus 14.4% of patients within the matching cohort (P = 0.0009). The highest rate of TTV infection was in patients with concurrent HCV/HIV infection (54% vs 30%, P = 0.038). HIV-infected subjects with TTV had lower ALT levels than those without TTV (P = 0.036). Intravenous drug use was the leading factor associated with TTV positivity among HIV-positive subjects. Mixed genotypes were more common in those with HIV. Therefore, TTV prevalence, ALT levels, and genomic heterogeneity of TTV all seem to be altered in patients with HIV.