Sex distribution, age of onset and HLA profiles in two types of multiple sclerosis. A role for sex hormones and microbial infections in the development of autoimmunity?

Fifty-four patients with clinically definite multiple sclerosis were typed for HLA-A, B, C, DR and DQ antigens. HLA-DQ was not a better disease marker than the previously described HLA-DR and B markers. The patients were subdivided according to the clinical evolution of their disease, age at onset and sex. HLA-DR2 was significantly associated with females having a relapsing-remitting course of the disease and HLA-B8 and B35 were significantly associated with males having a chronic-progressive course of the disease. A role is postulated for defects in the sex hormone balance in females and for microbial infections in males as dominant environmental triggers in the development of autoreactivity.