Antinuclear Factor in Rheumatoid Arthritis

Abstract

The results of repeated ANF tests in 273 patients with classical or definite rheumatoid arthritis have been studied in retrospect. Considering initial tests only, 81% were negative and 19% positive. Taking all tests into account, 77% of the initial 273 cases remained negative, 13% remained positive, and 10% varied, having both positive and negative results. This should be compared with an incidence of less than 1% of positive tests found in a normal population using the method described, and an incidence of 100% in 62 cases of clinically active systemic lupus erythematosus. The finding of a positive test does not seem to imply that the arthritis will pursue a less favorable course. Nodules and a positive DAT [Waaler-Rose] are encountered more commonly in the positive group and there is a significantly higher incidence of vascular lesions, infections, ocular lesions (especially kerato-conjunctivitis sicca), and Felty''s syndrome. The two latter conditions are particularly frequent in patients with a persistently positive ANF test. In some cases the results of the test may vary from year to year. It has not been found possible to correlate these changes with any simultaneous change in clinical or laboratory findings nor with any alteration in therapy. It is, however, apparent that these patients have a lower incidence of ocular lesions and of Felty''s syndrome than those with a consistently positive test.