Dravet syndrome - considerable delay in making the diagnosis

Objectives To assess delay in diagnosis and clinical characteristics of Dravet syndrome based on the Dravet register at The National Centre for Epilepsy in Norway. Material and methods - Medical records of patients diagnosed with Dravet syndrome since 2007 were analysed. Results - Twenty- two patients were identified. In 15, genetic screening disclosed mutations / deletions in the SCN1A gene. Average time from seizure onset to diagnosis was 7.4 years. Mean age at seizure onset was 6.7 months, nine had hemiconvulsions and 13 had generalized tonicclonic seizures. The seizures were precipitated by fever in 17, by external heating in three. During second year of life, multiple seizure types and cognitive and motoric stagnation occurred. No patients became seizure- free with antiepileptic drugs. The effect of vagal nerve stimulation was disappointing. Conclusions - By making an early diagnosis, an extensive presurgical evaluation may be avoided, and the patient and their parents may be offered genetic guidance.