Rheumatoid Factor: How often is it a False Positive?

Rheumatoid factors are antibodies against the Fc portion of IgG (also an antibody). They can belong to any isotype of immunoglobulin – eg, IgM, IgG and IgE – and any of these can be detected in the blood test.[1] Enzyme-linked immunosorbent assay (ELISA) can differentiate between the different subtypes. When to measure Any patient who is […]