Rheumatiod factor isotype in rheumatiod arthritis patients

Rheumatiod factor in patients with Rheumatoid arthritis [RA] could be oflgM, IgG, or IgG isotypes. To study the occurance of each or all these isotypes in RA patients. Enzyme linked Immune Sorbent Assay [ELISA] and Latex agglutination test were used to asses RF in 74 patients with RA. Using ELISA, 58 [78.4%] patients had positive RF [IgM 48.6%, IgG in 47.3% and IgA in 54.1%], while only 43 [58.1] patients were positive by AG. All RF isotypes should be assessed in patients with RA