ABSTRACT
Objective To analyze the causes of misdiagnosis and mistreatment of Dravet syndrome. Methods Patients with Dravet syndrome diagnosed according to clinical features and SCN1A gene mutation detection were recruited within recent 3 years. The patients were grouped into correct diagnosis-treatment group and misdiagnosis-mistreatment group according to whether the patients had ever been misdiagnosed and mistreated by sodium channel blockers. The clinical features were compared between two groups. Results Thirty-five cases with Dravet syndrome were collected and the rate of misdiagnosis reached 40%, Nine cases were misdiagnosed as symptomatic focal epilepsy, 4 as Lennox-Gastaut syndrome and 1 as Doose syndrome. The average age of onset in misdiagnosis-mistreatment group was (5.50 ± 3.56) months,and the age of confirmed diagnosis was (83.57 ± 105.62) months. The percentage of abnormal EEG, onset seizure with partial seizure, the seizure frequency within the first year from onset, onset with afebrile seizure, patients with status epilepticus or cluster seizures was higher in misdiagnosis-mistreatment group but it showed no significant statistical significance when compared with that of correct diagnosis-treatment group. The percentage of patients with mental retardation and focal neurological signs was significantly higher in misdiagnosis-mistreatment group (P=0.005 and 0.002, respectively). Conclusions Dravet syndrome is frequently misdiagnosed as symptomatic focal epilepsy. The appearance of focal neurological signs and mental retardation before confirmed diagnosis are important factors for misdiagnosis. Gene mutation screening will be helpful for differential diagnosis of Dravet syndrome.