The aims of this study were: to describe the clinical characteristics and brain images of patients with Multiple Sclerosis (MS) who presented seizures attributable to this entity, and to determine risk factors for recurrence of seizures in this population. 

Seizures are an atypical presentation form of MS. However, the prevalence of epilepsy in MS patients is more frequent than in the general population. Current data comes mainly from case series and there is little information in Latin-American populations.

Retrospective review of clinical records from adult MS patients evaluated between January/2011 and July/2021, at a tertiary center who had presented at least one seizure without other causes than MS. Demographic features, clinical characteristics, ancillary methods, and response to antiepileptic drugs (AED) were analyzed. A logistic regression analysis was performed to assess risk of seizure recurrence.

Out of 1277 patients who met criteria for MS diagnosis, 23 were included (female n=17). Prevalence of epilepsy due to MS was 1.8%. Median age at MS diagnosis was 30 years-old. Fifteen patients had RRMS (65%), 6 SPMS (26%), and 2 PPMS (9%). Median age at first seizure was 36.8 years. About 65% had focal seizure onset, and 30% presented a single episode. Eighty one percent received AED. Response to treatment resulted in seizure control in 96%, but 13% developed drug resistant epilepsy. Brain MRI showed that 35% of patients had cortical, and 82% juxtacortical lesions. No predictors of seizure recurrence were found.