Seizures in multiple sclerosis

Purpose: In patients with multiple sclerosis (MS), epileptic seizures occur more frequently than in the general population. The aim of this study was to analyze clinical characteristics of epilepsy in patients with MS, potential correlation between the semiology of seizures, EEG and magnetic resonance imaging (MRI) findings in these patients, as well as to examine the response to anticonvulsant therapy. Methods: In a series of 268 consecutive patients with definite MS hospitalized at the Institute of Neurology, Belgrade, we identified 20 (7.5%) patients with seizures or epilepsy. All patients with seizures or epilepsy were submitted to standard EEG and brain MRI with gadopentetate dimeglumine. Results: In four patients, epilepsy occurred 1-5 years before other clinical manifestations of MS. Eight patients had seizures only during MS relapses (provoked seizures). In two of them, seizures were the only manifestations of relapse. In 12 patients, seizures occurred regardless of the phase of MS (chronic epilepsy). In the majority of patients, seizures were partial with secondary generalization. Five patients experienced episodes of status epilepticus, and they all had dementia. Abnormal EEG pattern was found in 11 patients. Brain MRI disclosed cortical-subcortical lesions in nine patients and focal cortical atrophy in one, whereas in the remaining patients, findings were inconclusive. Probable EEG-MRI-seizure type correlation existed in 10 patients. Conclusions. Our data suggest that epilepsy may represent an initial symptom of MS and a single clinical manifestation of a relapse, and further support the assumption of the existing correlation between the presence of cortical-subcortical lesions and epileptic seizures or epilepsy in patients with MS.