01843nas a2200361   4500000000100000008004100001260001300042653001500055653001000070653000900080653002600089653001000115653002600125653001800151653001900169653003700188653001100225653001100236653001200247653000900259653001600268653002200284653001700306100001400323700001400337700001300351700001600364245010800380300001000488490000700498520096200505022001401467       1983                            d  c1983 Aug10aAdolescent10aAdult10aAged10aArthritis, Rheumatoid10aChild10aComplement Activation10aComplement C310aComplement C3c10aEndocarditis, Subacute Bacterial10aFemale10aHumans10aleprosy10aMale10aMiddle Aged10aRheumatoid Factor10aTuberculosis1 aReyes P A1 aMaluf J G1 aCurd J G1 aVaughan J H00aAssociation of rheumatoid factor with complement activation in rheumatoid arthritis and other diseases.  a391-60 v533 a<p>Rheumatoid factor (RF) is a complement activating autoantibody. In rheumatoid arthritis (RA) the rate of catabolism of complement is closely related to the titre of RF. Therefore, we have examined whether these relationships are unique to RA or will be found in non-RA disorders in which RF may be found in the circulation. We studied patients with subacute bacterial endocarditis, leprosy, tuberculosis, and a variety of other rheumatic and vasculitic disorders. We found that in all the disorders examined the RF had a complement activating potential which was equivalent to that of the RF of RA patients. Furthermore in vivo activation of complement, as exhibited by the appearance of C3 degradation products, was significantly related to higher titres of haemolytically active RF in non-RA as well as the RA group. In these respects, therefore, the RF in RA and non-RA patients is indistinguishable. A possible survival value for RF is discussed.</p>  a0009-9104