HLA Dw4 in adult and juvenile rheumatoid arthritis

HLA-D typing using homozygous typing cells (HTC) has shown a marked increase in HLA-Dw4 in adult patients with rheumatoid arthritis (RA). In an earlier study, Dw4 was found in 48% of patients and 8% of controls. In the present series, the frequencies are 59% and 16%, respectively. HLA-Dw4 does not appear to be increased in two small groups of non-white patients (black and Mexican-American). It also was not found to be increased in children with juvenile RA or in any of the three clinical subgroups of this disease. Another determinant, LD-TMo, was increased in arthritis developing in children. Thus, different immunogenetic factors appear to characterize clinically distinguishable forms of arthritis. The basis for these different HLA-D associations is presently unknown.