Evaluation of Hepatitis C Virus as a Risk Factor for HIV-Associated Neuroretinal Disorder.

Hepatitis C virus (HCV) is a newly identified risk factor for HIV-associated neuroretinal disorder (HIV-NRD). Genetic analysis suggests that alterations in the anti-inflammatory IL-10 signaling pathway increase susceptibility to both HIV-NRD and HCV infection. Inflammation may provide a mechanistic link between HCV and HIV-NRD.Background. Both hepatitis C virus (HCV) and human immunodeficiency virus (HIV) penetrate the central nervous system. HIV-associated neuroretinal disorder (HIV-NRD), a visual impairment of reduced contrast sensitivity and reading ability, is associated with cytokine dysregulation and genetic polymorphisms in the anti-inflammatory interleukin 10 (IL-10) signaling pathway. We investigated associations between HCV and HIV-NRD and between HCV and single-nucleotide polymorphisms (SNPs) in the IL-10 receptor 1 (IL10R1) gene.Methods. Logistic and Cox regression analysis were used to analyze risk factors for HIV-NRD in 1576 HIV-positive patients who did not have an ocular opportunistic infection at enrollment. Median follow-up was 4.9 years (interquartile range, 2.4–8.8 years). Four IL10R1 SNPs were examined in a subset of 902 patients.Results. The group included 290 patients with chronic HCV infection, 74 with prior infection, and 1212 with no HCV markers. There were 244 prevalent cases of HIV-NRD and 263 incident cases (rate = 3.9/100 person-years). In models adjusted for demographics, HIV treatment and status, liver function, and immune status, both the prevalence and incidence of HIV-NRD were significantly higher in patients with chronic HCV infection (odds ratio = 1.54; 95% confidence interval [CI], 1.03–2.31 and hazard ratio = 1.62; 95% CI, 1.13–2.34, respectively), compared to patients with no HCV markers. Chronic HCV was associated with rs2228055 and 2 additional IL-10R1 SNPs expected to reduce IL-10 signaling. HIV-NRD was not significantly associated with these SNPs.Conclusions. HCV is a possible risk factor for HIV-NRD. Genetic analysis suggests that alterations in the IL-10 signaling pathway may increase susceptibility to HIV-NRD and HCV infection. Inflammation may link HCV and HIV-NRD. [ABSTRACT FROM AUTHOR]