Epilepsy in Multiple Sclerosis

Abstract

In a series of 2,353 multiple sclerosis (MS) patients, 40 subjects presented seizures, with an overall prevalence of 1.70%. The prevalence was 2.33% (34/1,459) in definite MS cases, 0.58 in probable cases (3/518), 0.79 in possible cases (3/376). Twenty-six patients were females, 14 were males. In 13 cases, epilepsy had begun before MS onset; in 4 patients, the two diseases started contemporarily; in 23 patients, epilepsy followed MS onset. No relationship was found between frequency of seizures and course of MS nor between frequency of seizures and MS severity. In 12 patients, magnetic resonance imaging was performed: plaques adjacent to the cerebral cortex were found in 3 cases. The electroencephalogram showed paroxysmal discharges in 11 patients (focal in 2, diffuse in 9). Slow theta and/or delta activity was found in 15 patients (focal in 7, diffuse in 6, both focal and diffuse in 2). The EEG was normal in 14 patients. Possible etiological factors other than MS were recognized in 4 patients only: cranial trauma in 3, meningitis in 1. Our study on a large MS population confirms that MS is associated to a risk for epilepsy higher than that of the general population.

The pathophysiology of multiple sclerosis⋮ the mechanisms underlying the production of symptoms and the natural history of the disease

“…The phenomenon presumably arises from the self cross-excitation of a large population of neurons via an ephaptic interaction, but whether this interaction occurs within the central demyelinating lesion or within the dorsal horn is currently uncertain. If it occurs in the grey matter, it may indicate mechanisms similar to those involved in epilepsy, which is reported to occur more commonly in MS than in the general population (an incidence of 2.3% in de¢-nite MS; Ghezzi et al 1990). …”

Extensive cortical inflammation is associated with epilepsy in multiple sclerosis

“…With a mean prevalence value of 2.3 % (range 0.5-10 %) [1][2][3][4], epilepsy is three to six times more frequent in MS than in the general population (0.4 to 0.8 %) [5]. Moreover, MS may present with epilepsy [6,7] and, in some cases, seizures may be the only manifestation of a MS relapse [8].Whether the two diseases occur accidentally,or MS non-specifically triggers a latent proneness to epilepsy, or MS is the actual causation of seizures is still debated [9].…”

Recurrent Seizures and Prolonged Post-Ictal Aphasia in a Patient with Multiple Sclerosis

“…Cortical and subcortical involvement found on post-mortem studies were thought to contribute to the pathophysiology of convulsions in patients with MS. As many as 25% of such patients had plaques adjacent to the cerebral cortex [5]. Compared to a 0.5% prevalence in the general population, the prevalence of seizures in MS patients varied from 1.7 to 8% [1,7]. Aphasia, on the other hand, is more uncommon in MS with a frequency of 0.7-1.0%, in spite of frequent involvement of the language pathways in the disease process [8].…”

“…Epilepsy, however, is more prevalent in patients with MS than in the general population [1]. Paroxysmal speech disorders are commonly observed in complex partial seizures [2], but their association with seizures in MS patients is rare and has not been well studied [3].…”