ABSTRACT
The primary antiphospholipid syndrome (APS) is characterized by a peculiar clinical picture: thrombosis, recurrent fetal loss, and thrombocytopenia. In APS patients with haemolytic anemia, the authors have been able to elute from erythrocytes bound immunoglobulins displaying a reactivity against different negatively and neutrally charged phospholipids. The anti-endothelial cell antibodies look quite comparable to those found in systemic lupus erythematosus (SLE) patients without antiphospholipid antibodies (aPL), underlying once again the likeness of the serologic abnormalities between APS and SLE. The high prevalence of an antiendothelial activity in aPL-positive sera seems to be related both to the presence of antibodies reacting with β2-glycoprotein I adhered on endothelial cells and to distinct antiendothelial antibodies directed against different constitutive endothelial proteins. Antimitochondrial antibodies have been recognised as a heterogeneous group of autoantibodies classified according to their mitochondrial antigen specificity and disease association. In patients with APS secondary to another autoimmune disease, the presence of antinuclear antibodies is just the logical consequence of the association.
