Which test is used to confirm the results of an ELISA test?

The Western Blot test is a specific assay used to confirm the results of an ELISA (Enzyme-Linked Immunosorbent Assay) test, particularly in the context of detecting antibodies to certain infections, such as HIV. The ELISA test is a sensitive first-line screening test, but it may yield false positives. Therefore, the Western Blot serves as a confirmatory test because it is more specific and provides detailed information about the presence of various proteins, allowing for a more definitive diagnosis.

Unlike the Western Blot, which is specifically designed to confirm the presence of antibodies, other options do not serve the same confirmatory role in this context. For instance, a Rapid Antigen Test is used for quick detection of antigens associated with an infection rather than confirming antibody presence. A CD4 Count is a measure of the immune system's health in individuals with HIV but does not confirm ELISA results. An Antibody Profile may provide a range of antibody statuses but isn’t used strictly as a confirmation for ELISA results. Thus, the Western Blot remains the gold standard for verification following an initial positive ELISA test.