title: Clinically mild infantile encephalopathy associated with excitotoxicity.
abstract: Acute infectious encephalopathy is very frequently observed in children in East Asia including Japan. Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is the most common subtype in Japan; however, more than 40% of the patients remain unclassified into specific syndromes. To investigate the underlying pathomechanism in those with unclassified acute encephalopathy, we evaluated brain metabolism by MR spectroscopy. Among 20 patients with acute encephalopathy admitted to our hospital during January 2015 to May 2016, 12 could not be classified into specific syndromes. MR spectroscopy was performed in 8 of these 12 patients with unclassified encephalopathy. MR spectroscopy showed an increase of glutamine with a normal N-acetyl aspartate level on days 3 to 8 in three of the 8 patients, which had normalized by follow-up studies. The three patients clinically recovered completely. This study suggests that excitotoxicity may be the underlying pathomechanism in some patients with unclassified mild encephalopathy.
authors.affiliation: Department of Pediatrics, Tokyo Women's Medical University Yachiyo Medical Center, Yachiyo, Japan.
authors.forename: Nozomi
authors.initials: N
authors.lastname: Hirai
authors.affiliation: Department of Medical Technology and Image Laboratory, Tokyo Women's Medical University Yachiyo Medical Center, Yachiyo, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yoshimaru
authors.affiliation: Department of Pediatrics, Tokyo Women's Medical University Yachiyo Medical Center, Yachiyo, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Moriyama
authors.affiliation: Department of Pediatrics, Tokyo Women's Medical University Yachiyo Medical Center, Yachiyo, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Honda
authors.affiliation: Department of Pediatrics, Tokyo Women's Medical University Yachiyo Medical Center, Yachiyo, Japan.
authors.forename: Kumi
authors.initials: K
authors.lastname: Yasukawa
authors.affiliation: Department of Pediatrics, Tokyo Women's Medical University Yachiyo Medical Center, Yachiyo, Japan. Electronic address: jtaka@twmu.ac.jp.
authors.forename: Jun-Ichi
authors.initials: JI
authors.lastname: Takanashi
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism*; D001927:Brain Diseases / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000378:metabolism*; D003244:Consciousness Disorders / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000378:metabolism; D018792:Encephalitis, Viral / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D018698:Glutamic Acid / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism; D006801:Humans; D007223:Infant; D007564:Japan; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D012189:Retrospective Studies; D019349:Roseolovirus Infections / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000378:metabolism
chemical_list: D005973:Glutamine; D018698:Glutamic Acid
keywords: Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD); Encephalopathy; Excitotoxicity; Glutamate; Glutamine; MR spectroscopy