title: A case with anti-galactocerebroside antibody-positive Mycoplasma pneumoniae meningoencephalitis presenting secondary hypersomnia.
abstract: Galactocerebroside (Gal-C) is a major myelin component in the central nervous system. The anti-Gal-C antibody induced by mycoplasma infection may therefore be involved in the pathogenic mechanisms of mycoplasma-associated encephalitis. Here we report an adult case of mycoplasma encephalitis developing excessive daytime sleepiness. Brain MRI suggested that hypothalamic involvement was compatible with hypersomnia. This finding was corroborated by decreased hypocretin-1 in cerebrospinal fluid (CSF) and the manifestation of diabetes insipidus. Screening for anti-glycolipid antibody profiles showed the selective increase of serum anti-Gal-C antibody. After treatment with minocyclin, the patient's daytime sleepiness was markedly improved and the CSF hypocretin-1 level became almost normal, as well. It is known that CSF hypocretin-1 is decreased in Guillain-Barré syndrome mediated by anti-glycolipid antibody, suggesting a possible mechanistic link between anti-glycolipid antibodies and hypothalamic involvement. The present case further emphasizes the broad spectrum of neurological complications after mycoplasma infection.
authors.affiliation: Department of Neurology, Tohoku University School of Medicine, 1-1 Seiryomachi, Aobaku, Sendai, 980-0872, Miyagi, Japan. sugeno@med.tohoku.ac.jp
authors.forename: Naoto
authors.initials: N
authors.lastname: Sugeno
authors.forename: Norihiko
authors.initials: N
authors.lastname: Kawaguchi
authors.forename: Takafumi
authors.initials: T
authors.lastname: Hasegawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Kuroda
authors.forename: Ichiro
authors.initials: I
authors.lastname: Nakashima
authors.forename: Takashi
authors.initials: T
authors.lastname: Kanbayashi
authors.forename: Susumu
authors.initials: S
authors.lastname: Kusunoki
authors.forename: Masashi
authors.initials: M
authors.lastname: Aoki
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000097:blood; D003937:Diagnosis, Differential; D006970:Disorders of Excessive Somnolence / Q000097:blood* / Q000175:diagnosis / Q000209:etiology; D005699:Galactosylceramides / Q000097:blood*; D006801:Humans; D008297:Male; D008590:Meningoencephalitis / Q000097:blood* / Q000175:diagnosis / Q000209:etiology; D009177:Mycoplasma pneumoniae; D011019:Pneumonia, Mycoplasma / Q000097:blood* / Q000150:complications / Q000175:diagnosis
chemical_list: D001323:Autoantibodies; D005699:Galactosylceramides; C002454:galactocerebroside