Hepatitis C: an Overview of Various Laboratory Assays with their Mode of Diagnostic Cooperation.

Background: This review describes in chronological order the different assays for hepatitis C virus (HCV) antibodies, for the core antigen and for the HCV-RNA.

Methods: By ascending chronological order, the enzyme-linked immunosorbent assay (ELISA), rapid diagnostic tests (RDTs), HCV-Ab IgG avidity index (HCV AI), and Cy3-labeled microarray assay have been described for HCV antibodies in addition to ELISA for the total HCV core antigen (Ag).

Results: The recombinant immunoblot assay (RIBA) is a confirmatory test for HCV-Ab in blood, which is no longer needed due to the use of the sensitive third and fourth generation ELISA in addition to HCV-RNA detection by the Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). ELISA and RIBA measure current and prior exposure to HCV infection, but cannot discriminate between the two. RT-PCR is performed after ELISA for the diagnosis of HCV infection whether acute, chronic, false positive or false negative ELISA.

Conclusions: The cooperation between ELISA and RT-PCR in the diagnosis of HCV infection has been tabulated and discussed. HCV genotyping and subtyping testing is essential in pre-treatment evaluation of the patients for setting valuable treatment strategies and in understanding the epidemiology of the virus.