Antigens of the major histocompatibility complex in patients with chronic discoid lupus erythematosus.

The frequencies of the major histocompatibility complex class I, class II and class III antigens were determined in 130 patients (88 women and 42 men) with chronic discoid lupus erythematosus, and compared with those of 764 healthy controls. A significant increase in HLA-B7 (38.0% in the patients vs. 25.8% in the control group), HLA-B8 (29.5% vs. 17.4%), HLA-Cw7 (58.9% vs. 26.1%), HLA-DR2 (46.9% vs. 29.7%), HLA-DR3 (32.0% vs. 19.4%), HLA-DQw1 (76.6% vs. 60.5%), and a decrease in HLA-A2 (41.9% vs. 55.7%) was found. The calculated relative risk values for the respective antigens markedly increased when two or more antigens were present in one patient, with a maximum relative risk value of 7.4 for the combinations of HLA-Cw7, DR3, DQw1 and HLA-B7, Cw7 and DR3, which were found in 17.2% of the patients and in only 2.3% of the controls.