Seizures and epilepsy (≥2 unprovoked seizures) are more common in patients with APS compared with the general population.6,10 Between 3% and 10% of patients with APS have seizures/epilepsy, a prevalence that is 10 times greater than that of the general population.10 In half of these patients, epilepsy onset is after diagnosis.3 Epilepsy is more common in APS secondary to SLE vs primary APS (13.7% vs 6%; P <.05).11 Evidence of a correlation between aPL positivity and seizure is inconclusive.10 Seizures and epilepsy in patients with APS are primarily attributable to vascular disease.6 In a cohort study of 538 patients with APS, the odds ratio for epilepsy was 4.05 (95% CI, 2.05-8.00) in those with a prior central nervous system thromboembolic event.11 Epilepsy was also associated with higher rates of thrombocytopenia, livedo reticularis, and autoimmune hemolytic anemia.11 Some patients with APS with epilepsy have normal brain MRI results,3 and in vitro studies have implicated interactions between autoantibodies and neural structures.6