HLA antigens in brucellosis.

106 patients diagnosed as having brucellosis were typed for HLA class I and class II antigens. The number of healthy controls was 272 and 102 for classes I and II, respectively. 17 HLA-A, 31 HLA-B, 7 HLA-C and 8 HLA-DR specificities were studied. The most important finding was a highly significant decrease of the HLA-Cw2 antigen frequency in the patient group compared with the controls. The corrected p value was p less than 0.0001 (Fisher's test). This finding is compatible with the idea that HLA-Cw2 antigen could be a protective factor. No other positive or negative association was observed. There was no significant difference in HLA antigen frequencies between patients with and without joint manifestations. In addition, we did not find an HLA-B27 increase in the group of patients with brucellosis associated spondylarthritis when compared with healthy individuals.