Longitudinal survey of anticardiolipin antibodies in systemic lupus erythematosus. Relationships with clinical manifestations and disease activity in an Italian series.

One hundred and two patients suffering from systemic lupus erythematosus were observed over 5-140 months. IgG and IgM anticardiolipin antibodies (aCL) were searched for by ELISA in 448 serum samples, and were found in 88 (86.3%) patients on at least one occasion. Changes of aCL levels and isotypes were recorded in most patients. In patients with medium (20-80 U. GPL and/or MPL) and high (> 80 U. GPL and/or MPL) aCL levels associations with thrombosis, neurological manifestations, cerebrovascular disease, prolonged aPTT, and thrombocytopenia were found. A highly significant statistical association was found between IgG aCL and the occurrence of active disease (p < 0.0001).