title: A patient with anti-aquaporin 4 antibody who presented with recurrent hypersomnia, reduced orexin (hypocretin) level, and symmetrical hypothalamic lesions.
abstract: Recent studies have demonstrated that hypothalamic lesions associated with brain tumor, head trauma, and encephalopathy can cause symptomatic hypersomnia with a reduced orexin (hypocretin) level in the cerebrospinal fluid (CSF). Aquaporin 4 (AQP4), a member of the AQP superfamily, is strongly expressed in the hypothalamus in which orexin (hypocretin)-containing neurons are primarily concentrated. We report the case of a patient with a serum anti-AQP4 antibody who presented with recurrent hypersomnia, symmetrical hypothalamic lesions with long spinal cord lesions on MRI, and a reduced CSF orexin (hypocretin) level, all of which were improved simultaneously by steroid therapy. Further studies should be performed to determine the roles of anti-AQP4 antibody positivity in patients with hypersomnia associated with orexin (hypocretin) deficiency and hypothalamic lesions.
authors.affiliation: Department of Neurology, Brain Research Institute, Niigata University, 1-757 Asahi-machi-dori Niigata, Niigata 951-8585, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Nozaki
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Shimohata
authors.forename: Takashi
authors.initials: T
authors.lastname: Kanbayashi
authors.forename: Youhei
authors.initials: Y
authors.lastname: Sagawa
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Katada
authors.forename: Masahisa
authors.initials: M
authors.lastname: Satoh
authors.forename: Osamu
authors.initials: O
authors.lastname: Onodera
authors.forename: Keiko
authors.initials: K
authors.lastname: Tanaka
authors.forename: Masatoyo
authors.initials: M
authors.lastname: Nishizawa
mesh_terms: D000328:Adult; D000906:Antibodies / Q000097:blood*; D051401:Aquaporin 4 / Q000276:immunology*; D002574:Cervical Vertebrae; D006970:Disorders of Excessive Somnolence / Q000378:metabolism* / Q000473:pathology*; D005260:Female; D006801:Humans; D007031:Hypothalamus / Q000473:pathology*; D047908:Intracellular Signaling Peptides and Proteins / Q000134:cerebrospinal fluid*; D009479:Neuropeptides / Q000134:cerebrospinal fluid*; D000068797:Orexins; D013116:Spinal Cord / Q000473:pathology; D013904:Thoracic Vertebrae
chemical_list: C496030:AQP4 protein, human; D000906:Antibodies; D051401:Aquaporin 4; D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D000068797:Orexins