Arthropathy of Down syndrome.

A juvenile rheumatoid arthritis-like arthropathy has previously been documented in 12 patients with Down syndrome. An additional 9 patients are described and the literature is reviewed. It is unknown whether these patients have juvenile rheumatoid arthritis or a unique arthropathy in light of the genetic and immunologic abnormalities associated with Down syndrome. Most of the patients had a progressive course with polyarticular disease complicated by subluxations and a long lag time to diagnosis. The purpose of reporting these children is to increase awareness of this association and facilitate more appropriate and timely diagnosis of arthritis in Down syndrome patients.