Epilepsia. 2012 Feb 6. doi: 10.1111/j.1528-1167.2011.03402.x. [Epub ahead of print]
Mutations of the SCN1A gene in acute encephalopathy.
Saitoh M, Shinohara M, Hoshino H, Kubota M, Amemiya K, Takanashi JL, Hwang SK, Hirose S, Mizuguchi M.
Source
Department of Developmental Medical Sciences, Graduate School of Medicine, University of Tokyo, Tokyo, Japan Division of Neurology, National Center for Child Health and Development, Hachioji, Japan Department of Neurology, Tokyo Metropolitan Hachioji Children's Hospital, Tokyo, Japan Department of Pediatrics, Kameda Medical Center, Kamogawa, Japan Department of Pediatrics and Research Institute for the Pathomechanisms of Epilepsy, Fukuoka University, Fukuoka, Japan.
Abstract
Purpose: Acute encephalopathy is the most serious complication of pediatric viral infections, such as influenza and exanthema subitum. It occurs worldwide, but is most prevalent in East Asia. Recently, there have been sporadic case reports of epilepsy/febrile seizure and acute encephalopathy with a neuronal sodium channel alpha 1 subunit (SCN1A) mutation. To determine whether SCN1A mutations are a predisposing factor of acute encephalopathy, we sought to identify SCN1A mutations in a large case series of acute encephalopathy including various syndromes. Methods: We analyzed the SCN1A gene in 87 patients with acute encephalopathy, consisting of 20 with acute necrotizing encephalopathy (ANE), 61 with acute encephalopathy with biphasic seizures and late reduced diffusion (AESD), and six with nonspecific (unclassified) acute encephalopathy. Key Findings: Three patients had distinct point mutations. Two of them had epileptic seizures prior to acute encephalopathy. Clinical and neuroradiologic findings of acute encephalopathy were diverse among the three patients, although all had a prolonged and generalized seizure at its onset. The first patient with V982L had partial epilepsy and AESD. The second patient with M1977L had febrile seizures and nonspecific acute encephalopathy. The third patient with R1575C had no seizures until the onset of ANE. M1977L was a novel mutation, whereas the remaining two, V982L and R1575C, have previously been reported in cases of Dravet syndrome and acute encephalopathy, respectively. Significance: These findings provide further evidence that SCN1A mutations are a predisposing factor for the onset of various types of acute encephalopathy.
Wiley Periodicals, Inc. ? 2012 International League Against Epilepsy.
PMID:
22309220
[PubMed - as supplied by publisher]