Abstract
Objective: To summarize the early clinical features of Dravet syndrome (DS) patients with SCN1A gene mutations before the age of one. Methods: SCN1A gene mutation screening was performed by PCR–DNA sequencing and multiple ligation-dependent
probe amplication (MLPA). The early clinical features of DS patients with SCN1A mutations were reviewed with attention to the seizures induced by fever and other
precipitating factors before the first year of life. Results: The clinical data of 138 DS patients with SCN1A gene mutations were reviewed. The median seizure onset age was 5.3 months. Ninety-nine patients (71.7%) experienced seizures with duration more than
15 min in the first year of life. Two or more seizures induced by fever within 24 h or the same febrile illness were observed in 93 patients (67.4%). 111 patients (80.4%)
had hemi-clonic and (or) focal seizures. Seizures had been triggered by fever of low
degree (T < 38 °C) in 62.3% (86/138) before the first year of life. Vaccine-related seizures were
observed in 34.8% (48/138). Seizures in 22.5% (31/138) of patients were triggered
by hot bath. Carbamazepine, oxcarbazepine, lamotrigine, phenobarbital and phenytoin
showed either no effect or exacerbating the seizures in our group. Conclusion: The seizure onset age in DS patients was earlier than that was in common febrile
seizures. When a baby exhibits two or more features of complex febrile seizures in
the first year of life, a diagnosis of DS should be considered, and SCN1A gene mutation screening should be performed as early as possible. Early diagnosis
of DS will help clinicians more effectively prescribe antiepileptic drugs for stronger
prognosis.
Keywords
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Article info
Publication history
Published online: October 28, 2013
Accepted:
October 9,
2013
Received in revised form:
August 23,
2013
Received:
May 5,
2013
Identification
Copyright
© 2013 The Japanese Society of Child Neurology. Published by Elsevier Inc. All rights reserved.
