Role of virus for the induction of myasthenia gravis.

Virus has been suggested as an etiological agent in myasthenia gravis. In this investigation 36 patients with the clinical diagnosis of myasthenia gravis were tested for antibodies against ornithosis, mycoplasma pneumoniae and 16 viral antigens. Rabbits with experimentally induced autoimmune myasthenia gravis were similarly tested. There was no overall correlation to any microorganism, which might have suggested the involvement of a viral infection in the pathogenesis of the disease. Neither was there any difference in incidence of antibodies in female patients carrying the HLA B8 antigen, an antigen which is associated with myasthenia gravis, as compared to HLA B8 negative individuals.