The seronegative spondyloarthropathies of childhood.

Most chronic arthritis in childhood is seronegative. Within "JRA" several distinct subgroups exist: one of these (pauciarticular disease type II) affects predominantly boys more than 8 years of age. It is clearly associated with sacroiliitis, HLA-B27, family history of spondyloarthropathy, and subsequent ankylosing spondylitis in an as yet underfined percentage of patients. This type of disease is probably classified appropriately with the spondyloarthropathies, although patients often may fulfill diagnostic criteria for "JRA" in the first years of their disease, and accounts for about 15% of "JRA." The other JRA subgroups do not appear to have features of seronegative spondyloarthropathy. Reiter's syndrome and psoriatic arthritis exist in children, but appear to be rare. The arthritis of inflammatory bowel disease in childhood resembles that in adulthood. The recognition of spondyloarthropathy in children, particularly the sizable group of patients with "JRA" pauciarticular disease type II, is of practical importance to permit proper therapy, follow-up and prevention of deformity.