Accelerated decline in anti-HCV antibody levels in spontaneous HCV seroconverters with HIV co-infection

Abstract

Objective To investigate the influence on anti-HCV antibody levels in spontaneous HCV seroconverters co-infected with HIV. Methods A retrospective study was conducted on people with a history of blood donation in Wangying Village, Shangcai County, Henan Province in 2009 and 2017.According to the infection status in 2009, patients who were positive for anti-HCV antibody were divided into four groups: HIV-negative chronic HCV infection group (HCVc), HIV-negative spontaneous HCV clearance group (HCVr), HIV-positive chronic HCV infection group (HIV+ HCVc), HIV-positive spontaneous HCV clearance group (HIV+ HCVr). All patients were followed up in 2017 and those who were lost to follow-up, received HCV treatment or were reinfected with HCV (only for those of HCV seroconverters) were excluded from this study.Altogether 167 patients met the inclusion criteria (HCVc: n=65; HCVr: n=34; HIV+ HCVc: n=44; HIV+ HCVr: n=24). A horizontal comparison of anti-HCV antibody levels among the above four groups in 2009 and a longitudinal comparison of changes in anti-HCV antibody in each group from 2009 to 2017 were respectively conducted. Results The horizontal comparison indicated that the levels of anti-HCV antibody were higher in chronic HCV-infected patients than in HCV seroconverters no matter whether they were co-infected with HIV or not (both P<0.000 1). After comparison of anti-HCV antibody titers in 2017 and 2009, no significant changes were found in HCVc or HIV+ HCVc group.The levels of anti-HCV antibody in HCVr and HIV+ HCVr groups decreased significantly from 2009 to 2017 (both P<0.000 1). HIV+ HCVr group showed a faster decline in anti-HCV antibody level than HCVr group (P=0.003 9). Significant negative correlations between the decline speed in anti-HCV antibody sample/cut-off (S/CO) values and the initial anti-HCV antibody S/CO values (in 2009) were found in both HCVr (r=-0.517 7, P=0.001 7) and HIV+ HCVr groups (r=-0.753 2, P<0.000 1). The decline speed in anti-HCV antibody in HIV+ HCVr patients was found to be negatively correlated with their CD4+ T cell counts in 2009 (r=-0.563 8, P=0.004 1). Moreover, the seroreversion rate of anti-HCV antibody in patients of the HIV+ HCVr group was higher than that of HCVr group (P=0.027 5). Conclusion HIV co-infection can accelerate the decline of anti-HCV antibody in spontaneous HCV seroconverters.This study indicates that in a large-scale retrospective epidemiological investigation especially for HIV-infected populations, the prevalence of anti-HCV antibody may be underestimated. Key words: Anti-HCV antibody; Spontaneous HCV clearance; HIV co-infection; Decline in anti-HCV antibody; Correlation