Immunoglobulin E (IgE) levels in serum and synovial fluid in rheumatoid arthritis

Serum and synovial fluid levels of immunoglobulin E (IgE) were significantly increased in patients with rheumatoid arthritis (RA) but were normal in degenerative arthritis (DJD) and in samples taken at autopsy in cases without joint disease. No significant correlation was found between serum IgE concentration and severity of RA nor was evidence found of the local production of IgE in synovial fluid in RA. The increased IgE in RA may be the result of a general immune response seen in this disease.