Seronegative spondyloarthropathies and HLA antigens in a Mestizo population.

HLA-A and -B antigens incidence were investigated in 100 cases of Seronegative Spondyloarthropathies and in 303 control individuals of a Venezuelan Mestizo population. Significative increased incidence of B27 was found among 69% of patients with ankylosing spondylitis and 68% with Reiter syndrome being the incidence in the control group of 2.9%.