Epileptic seizures in early-onset multiple sclerosis.

Early-onset multiple sclerosis (EOMS) is defined as the first presentation of symptoms in childhood (before the age of 16 years). EOMS occurs in about 0.4% to 10.5% of multiple sclerosis (MS) patients. In this retrospective population-based study we aimed to describe the clinical/paraclinical details and frequency of epileptic seizures in Iranian EOMS patients registered with the Isfahan Multiple Sclerosis Society (IMSS) from April 2003 to July 2010. EOMS cases were extracted from the Isfahan total MS cohort and included 3522 patients. A total of 117 EOMS patients (19 males and 98 females) with a mean age at onset of 14.2 ± 2.0 years (range: 7-16 years) were extracted from our database (3.3% of the total cohort). Of cases, ten (one male and nine females) had experienced at least two epileptic seizures, providing a crude prevalence of 8.5%. The frequency of epilepsy in EOMS patients (8.5%, 10/117) was significantly greater (P < 0.001) than that of non-EOMS cohort (2.0%, 71/3405). Epileptic seizures occurred before MS onset in two patients, after MS onset in seven, and at MS onset in one as the presenting symptom of the disease. Our findings mostly indicate an excessive prevalence of epileptic seizures in Iranian EOMS patients (8.5%), which is higher than any other report concerning seizures or epileptic seizures in a large MS series.