The cystic form of rheumatoid arthritis

A non-erosive form of rheumatoid arthritis (R.A.) was found in 62 patients out of 660 patients with R.A. These 62 patients exhibit slowly progressive cystic changes in about the same joints in which usually erosions develop in classic R.A. The E.S.R. is often low, half of the patients remained seronegative and there are 35 males and 27 females in the group. A smaller group of 15 out of these patients could be followed from a stage wherein the radiographs were normal to a stage of extensive cystic changes, over a period of at least 6 years. An attempt is made to delineate this group within the Rheumatoid arthritis disease entity.