ANTIPERINUCLEAR FACTORS ARE PRESENT IN POLYARTHRITIS BEFORE ACR CRITERIA FOR RHEUMATOID-ARTHRITIS ARE FULFILLED

Objective-To show that antiperinuclear factor (APF) may be useful for the diagnosis of rheumatoid arthritis at a time when the American Coll ege of Rheumatology (ACR) criteria are not yet fulfilled. Methods-Test ing for APF-IgG (1:100 threshold) and rheumatoid factors (RF) was done in 60 patients with polyarthritis of recent onset during a three year follow up. Results-At the end of the study, 21/40 rheumatoid arthriti s were positive for RF and 31/40 for APF, including 18/40 cases (45%) in which ACR criteria were not yet fulfilled. Conclusions-APF are usef ul in the diagnosis of early rheumatoid arthritis.