Anti-hepatitis C virus antibody detection in oral fluid: Influence of human immunodeficiency virus co-infection

Abstract Background Saliva sampling may provide an easier access to hepatitis C virus (HCV) screening test. HIV infection influence on specific salivary antibody detection has not been extensively studied. Objectives An anti-HCV antibodies (HCV-Ab) test was adapted for saliva specimens and its performances were analysed according to the patients’ HIV status and related factors such as CD4 cell counts and HIV viral load. Methods Four patients groups were selected: (i) HCV and HIV negative volunteers ( n = 28); (ii) HCV positive and HIV negative patients ( n = 30); (iii) HCV negative and HIV positive patients ( n = 30); (iv) HCV and HIV co-infected patients ( n = 30). Saliva samples were collected (Salivette system, Sarstedt) and an in-house adapted HCV-Ab detection assay was performed (MONOLISA anti-HCV PLUS Version 2, Biorad). HIV viral load, CD4 cells counts and HCV viremic status were reported. Results Sensitivity and specificity of saliva anti-HCV antibody tests in the HIV negative groups were 90% and 100%, respectively, compared to 73% and 93%, respectively in the HIV infected population. Compared to the HIV negative population, HIV mono-infected patients presented higher absorbance values ( p = 0.01) and HIV/HCV co-infected population presented lower HCV-Ab absorbance values ( p < 0.001). Sensitivity decline was associated with HIV replication ( p = 0.02), HCV replication ( p = 0.16) but not with CD4 cell counts ( p = 0.64). Conclusion Performances of salivary HCV antibodies testing are strongly deteriorated in the HIV positive population, especially for patients with residual HIV replication. This serious limitation should prompt careful testing of non-invasive screening tests for hepatitis C in HIV-infected patients before use in real screening conditions.