Antiphospholipid antibodies in children without and in adults with and without thrombophilia

Antiphospholipid antibodies (APAs) are considered risk factors in patients with thromboembolic diseases. Although the incidence of such acquired coagu lation disturbances in adults are well described, only few data exist for c hildren. Therefore, in a first step to collect new data we analyzed the pre sence of different APAs in 202 consecutive children and compared them with two groups of adults. The children screened for APA were exclusively those who did not have any thromboembolic complications or a tendency for thrombo philia due to other underlying diseases such as systemic lupus or malignanc y in their past or present medical history. Consecutive blood samples were evaluated from routine laboratory specimens. The two groups of adults compr ised 200 patients after deep vein thrombosis and 200 patients without throm boembolic events that served as controls. Four lupus anticoagulant (LA) scr eening tests were determined: the dilute Russell's viper venom test; a lupu s danticoagulant-sensitive activated partial thromboplastin time reagent; a second lupus-sensitive activated partial thromboplastin time; and the Kaol in clotting time. Furthermore, three different antiphospholipid antibodies ELISA assays against cardiolipin (ACA), beta 2-glycoprotein I, and phosphat idyl-serine, were determined. The children had a much higher prevalence for LA than did the adults. On the other hand, their values for ACA were signi ficantly lower than in adults with a history of thromboembolism. Findings i n children were similar to the normal adult group. This has to be taken int o account when evaluating children with thromboembolic diseases. (C) 2000 E lsevier Science Ltd. All rights reserved.