Incidence of tonic spasms as the initial presentation of pediatric multiple sclerosis in Slovenia

Tonic spasms (TS) are involuntary movement patterns that can present in patients with multiple sclerosis (MS). They have been first described decades ago, but are frequently missed and misdiagnosed, particularly in the pediatric MS patients and if appearing ahead of hallmark neurological signs and symptoms of MS. Slovenia is a country with the population of about 2 million people. In the years from 1992 to 2016, we have treated 57 sequential pediatric patients with MS at our hospital, which is the only tertiary medical institution for treating children with MS in the country. We present the only two MS patients, a 17-year-old girl and a 14-year-old boy, whose first manifestation of MS were TS. This allowed us to estimate the incidence of TS in pediatric MS patients in Slovenia.