Cutaneous histopathologic findings in 'antiphospholipid syndrome'. Correlation with disease, including human immunodeficiency virus disease.

The term antiphospholipid syndrome is used to characterize a complex of clinical and pathologic findings mediated by a group of antibodies formed against a family of antiphospholipids. These antiphospholipid antibodies were originally found in patients with lupus erythematosus in whom the partial thromboplastin time was prolonged and in patients with other autoimmune diseases; subsequently, they have been observed in association with a variety of other conditions, including infections, reactions to drugs, malignant neoplasms, human immunodeficiency virus disease, and as an isolated finding. In recent years, there has been some clarification of the significance of the various tests for antiphospholipid antibodies, including the lupus anticoagulant test and the anticardiolipin antibody tests, in predicting the antiphospholipid syndrome. The mechanism of disease, however, has not been well defined. The most common cutaneous lesion seen in seven patients with lupus anticoagulant and anticardiolipin antibody who have the antiphospholipid syndrome was ulceration due to thrombosis of dermal veins and arteries. Often there is a reactive vascular proliferation around the thrombosed vessels. The presence of primary thrombosis of both veins and arteries in thrombotic disorders is unusual and may provide insight into the mechanism of thrombosis in antiphospholipid syndrome.