Abstracts

Rationale: Distinguishing patients with Lennox-Gastaut syndrome from Dravet syndrome in adult neurology clinic is challenging as both share some similar clinical features and previous childhood distinguishing features are not always available. We have previously reported that patients with Dravet syndrome present very peculiar motor phenotype. Here we sought to confirm that this association was not linked to the chronic use of antiepileptic drugs or the many lifetime seizures. Methods: To this aim, we studied 14 adult patients with Lennox-Gastaut syndrome and 14 adults with Dravet syndrome as both conditions share similar seizure severity. Results: We found that antecollis and parkinsonian gait were significantly more common in the Dravet group (P-value 0.0044 and 0.0128 respectively), thus suggesting that these features are part of the Dravet syndrome adult phenotype. Conclusions: These findings support the hypothesis that motor sings in Dravet syndrome may be linked to severe SCN1A mutations in basal ganglia neurons. The lack of parkinsonian features in Lennox-Gastaut syndrome helps differentiate them from DS patients in adults. Hence, it is essential to perform full neurological examination, particularly movement assessment in patients with epilepsy and intellectual disability. The presence or absence of these findings could guide the diagnosis and help personalize the treatment. Funding: none