RESUMO
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.