PRESENCE OF MULTIPLE ANTIPHOSPHOLIPID ANTIBODY SPECIFICITIES IN A PEDIATRIC POPULATION

Thrombotic related events are thought to be associated with the presen ce of anti-phospholipid antibodies (APA), However, the association of anti-cardiolipin antibody is much weaker than the association with ant ibodies to other phospholipids. Much of the literature equates antipho spholipid antibodies and anticardiolipin antibodies because of the rel ationship of APA and false positive tests for syphilis. However, recen tly the presence of antibodies to naturally occurring phospholipids ot her than cardiolipin have been reported. In fact, some investigators r eport that antibodies to phosphatidylserine appear to correlate more c losely to disease processes than anti-cardiolipin antibodies. We descr ibe here the presence of non-anti-cardiolipin antiphospholipid antibod ies in a pediatric population that lack anti-cardiolipin antibodies an d demonstrate the association of these antibodies with thrombotic dise ase. Antibodies to phosphatidic acid were the most prevalent and corre lated (p < .001) with thrombotic disease and idiopathic thrombocytopen ia purpura, The rank order of prevalence of antibodies to phospholipid s was phosphatidic acid, phosphatidylglycerol, phosphatidylinosital, p hosphatidylserine, cardiolipin and phosphatidylethanolamine. Antiphosp holipid antibodies of the three major sera isotypes were present in th e positive sera examined. These descriptive findings suggest that the significance of APA other than anti-cardiolipin antibodies in pediatri c patients should be further investigated.