Objective: To determine whether the occurrence of seizures is correlated with the presence of serum antiphospholipid antibodies (aPL) in systemic lupus erythematosus (SLE) patients.
Methods: The study included 221 unselected patients with SLE. Of these, 21 patients with epileptic seizures not attributed to any cause other than SLE were identified. Epilepsy was diagnosed by clinical history and electroencephalography. Blood samples were tested for the presence of antibodies to cardiolipin (aCL, IgG and IgM isotypes) and lupus anticoagulant (LAC).
Results: LAC was detected in 43.8% of the patients with epilepsy and in 20.8% of controls (P = 0.057). A statistically significant association was found between moderate-to-high titers of IgG aCL and the presence of seizures (P = 0.02). Brain computed tomography and/or magnetic resonance imaging scanning was performed in 14 patients. All patients with abnormal features found on these tests had positive aPL (P = 0.03). Nine patients (42.9%) had at least 1 of the classic features associated with the aPL syndrome.
Conclusion: We confirmed that epilepsy as a primary neuropsychiatric event is significantly associated with moderate-to-high titers of IgG aCL in SLE patients. Our results suggest that aPL could have a role in the etiopathogenesis of epilepsy in SLE.