Increased anticardiolipin antibody IgG titers do not predict recurrent stroke or TIA in children

Background: Increased anticardiolipin antibody (ACLA) immunoglobulin (Ig) G titers are commonly found in children with arterial ischemic stroke (AIS) or TIA (AIS/TIA). The associated risk of recurrent thromboembolism is unknown. Objective: To determine the risk of recurrent thromboembolism associated with persistently increased ACLA titers of the IgG isotype in children with AIS/TIA. Methods: The authors studied a cohort of children surviving first AIS/TIA tested by standardized ELISA for beta(2)-glycoprotein I-dependent ACLA of the IgG isotype. Children with ACLA titers >15 IgG phospholipid (GPL) units (per manufacturer's cutoff point) on more than two occasions greater than or equal to6 weeks apart were classified as ACLA-positive (ACLA+) and compared with ACLA-negative (ACLA-) children with respect to recurrent thromboembolic events (AIS/TIA, sinovenous thrombosis, and extracerebral thromboembolism). Results: The authors recruited 34 ACLA+ children and 151 ACLA- children. Most ACLA+ children (30/34; 88%) had ACLA titers less than or equal to40 GPL units. During the follow-up period (median duration, 2.8 years for ACLA+ children and 3.0 years for ACLA- children), AIS/TIA recurred in 26% of ACLA+ children and in 38% of ACLA- children; none developed sinovenous thrombosis or extracerebral thromboembolism. Based on survival analysis, this difference was nonsignificant (p=0.54). Using binary partition evaluation, no titer criteria for ACLA positivity (range, 0 to 60 GPL units) predicted recurrent AIS/TIA. Conclusion: In children surviving arterial ischemic stroke/TIA, increased anticardiolipin antibody immunoglobulin G titers do not predict recurrent thromboembolism.