ANTIPHOSPHOLIPID ANTIBODIES IN PATIENTS WITH IDIOPATHIC AUTOIMMUNE HEMOLYTIC-ANEMIA

Isolated cases of anti-phospholipid antibody (aPL)-associated idiopath ic autoimmune haemolytic anemia (IAHA) have been recently described. T o assess the significances of this association, we studied by ELISA th e presence of aPL in sera from 18 patients with IAHA and 14 patients w ith non-autoimmune haemolysis (NON-AH). Four IAHA cases and none of th e NON-AH controls showed IgM anticardiolipin antibodies (aCL) that cro ssreacted extensively with zwitterionic as well as with other anionic phospholipids. IgG aCL were detected in 6 patients with IAHA and in 1 patient with NON-AH; there was little cross-reactivity with other phos pholipids. Our results suggest that anti-phospholipid antibodies are p resent in a substantial number of patients with IAHA. This humoral res ponse does not seem to be secondary to the haemolysis proper. The pote ntial pathogenic significance of this finding is discussed.