Chronic polyarthritis in children, often called Still's disease in Great Britain after GF Still, who described 22 cases in 1897, is usually referred to elsewhere (eg in the USA) as' juvenile rheumatoid arthritis'. This nomenclature prejudges the issue. Is the condition really rheumatoid arthritis, such as occurs in adults, or is it a different disease? This problem has been confronting us at Taplow for more than 20 years: it is complicated by the likelihood that rheumatoid arthritis in adults may consist of a number of different entities, with different manifestations, different courses, and even with different pathogenetic mechanisms, and this suggests the possibility of different treatments. Themajority of hospitalized adult patients with rheumatoidarthritis are sero-positive, and this group seems a clear nosological entity, often associated withnodules ofa specific histological character. This arthritisis seen also (but rarely) in teenage children. Most patients with chronic polyarthritis in the general population, however, appear to be sero-negative. A few may be included in the latter category who will later be found to develop psoriasis, ulcerative colitis, Crohn's disease, Whipple's disease, ankylosing spondylitis, or other connective tissuedisorders. These are all uncommon and, as far as we know, the majority of such sero-negative adult arthritics develop no such stigmata, but remain for many years as cases of'sero-negative polyarthritis', usually with a milder and less progressive course than patients with sero-positive rheumatoid arthritis. It is to the former group that most of the female relatives of our children with Still's disease appear to belong (Ansell, Lawrence, and Bywaters, 1969).

To find adult patients developing a disease indistinguishable from Still's disease would imply that the latter is a nosological entity sui generis and not merely an age-related version of adult poly-arthritis. It would also complement the occurrence, at the opposite end of the scale, of children with sero-positive erosive nodular rheumatoid arthritis (as described above)(Bywaters, 1967). This paper sets out to show that the Still's disease syndrome occurs also in adults. In a descriptive study of therash of Still's disease (or'juvenile rheumatoid arthritis' as it is often called) published 14 years ago (Isdale and Bywaters, 1956), five adultpatients showing the same rash were briefly instanced. The present study con-