STUDIES OF IGG-CLASS ANTICARDIOLIPIN ANTIBODIES IN MYASTHENIA-GRAVIS

IgG-class anticardiolipin antibodies (IgG-ACA) were found in 25% of pa tients with myasthenia gravis. The prevalence and the level distributi on were significantly different from those of a normal donor populatio n (p < 0.001). In myastenic patients, IgG-ACA bound negatively charged , but not zwitterionic, phospholipids. They were significantly associa ted with the thymic abnormalities, thymoma and thymic hyperplasia, but not with various factors such as age, sex, antinuclear antibodies, se verity of the disease and clinical thrombosis. The IgG-ACA levels did not correlate with titers of anti-acetylcholine receptor antibodies. T hus in Myasthenia Gravis, asymptomatic IgG-ACA could reflect an immune dysregulation under the influence of thymic alterations.