title: Combined treatment of methylprednisolone pulse and memantine hydrochloride prompts recovery from neurological dysfunction and cerebral hypoperfusion in carbon monoxide poisoning: a case report.
abstract: A 49-year-old healthy man developed sudden unconsciousness under inadequate ventilation. Blood gas analysis showed carboxyhemoglobin of 7.3%. After normobaric oxygen therapy, he recovered completely 7 days later. At 3 weeks after carbon monoxide (CO) exposures, memory and gait disturbances appeared. Neurological examination revealed Mini-Mental State Examination (MMSE) score of 5 of 30 points, leg hyper-reflexia with Babinski signs, and Parkinsonism. Brain fluid-attenuated inversion recovery imaging disclosed symmetric hypointense lesions in the thalamus and the globus pallidus, and hyperintense lesions in the cerebral white matter. Brain single-photon emission tomography (SPECT) scanning with (99m)Technesium-ethyl cysteinate dimer displayed marked hypoperfusion in the cerebellum, the thalamus, the basal ganglia, and the entire cerebral cortex. He was diagnosed as CO poisoning and treated with hyperbaric oxygen therapy. The neurological deficits were not ameliorated. At 9 weeks after neurological onset, methylprednisolone (1000 mg/day, intravenous, 3 days) and memantine hydrochloride (20 mg/day, per os) were administered. Three days later, MMSE score was increased from 3 to 20 points. Neurological examination was normal 3 weeks later. Brain SPECT exhibited 20% increase of regional cerebral blood flows in the cerebellum, the thalamus, the basal ganglia, and the entire cerebral cortex. These clinicoradiological changes supported that the treatment with steroid pulse and memantine hydrochloride could prompt recovery from neurological dysfunction and cerebral hypoperfusion. Further clinical trials are warranted whether such combined therapy can attenuate neurological deficits and cerebral hypoperfusion in patients with CO poisoning.
authors.affiliation: Department of Neurology, Toho University Omori Medical Center, Tokyo.
authors.forename: Konosuke
authors.initials: K
authors.lastname: Iwamoto
authors.affiliation: Department of Neurology, Toho University Omori Medical Center, Tokyo. Electronic address: keni@med.toho-u.ac.jp.
authors.forename: Ken
authors.initials: K
authors.lastname: Ikeda
authors.affiliation: Department of Radiology, Toho University Omori Medical Center, Tokyo, Japan.
authors.forename: Sunao
authors.initials: S
authors.lastname: Mizumura
authors.affiliation: Department of Radiology, Toho University Omori Medical Center, Tokyo, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Tachiki
authors.affiliation: Department of Radiology, Toho University Omori Medical Center, Tokyo, Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Yanagihashi
authors.affiliation: Department of Neurology, Toho University Omori Medical Center, Tokyo.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Iwasaki
mesh_terms: D000978:Antiparkinson Agents / Q000627:therapeutic use*; D002249:Carbon Monoxide Poisoning / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy*; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D002561:Cerebrovascular Disorders / Q000139:chemically induced / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D004359:Drug Therapy, Combination; D005938:Glucocorticoids / Q000627:therapeutic use*; D006801:Humans; D006931:Hyperbaric Oxygenation; D008297:Male; D008559:Memantine / Q000627:therapeutic use*; D008775:Methylprednisolone / Q000627:therapeutic use*; D008875:Middle Aged; D020258:Neurotoxicity Syndromes / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D010302:Parkinson Disease, Secondary / Q000139:chemically induced / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D055420:Perfusion Imaging / Q000379:methods; D020551:Pulse Therapy, Drug; D020127:Recovery of Function; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon; D016896:Treatment Outcome
chemical_list: D000978:Antiparkinson Agents; D005938:Glucocorticoids; D008559:Memantine; D008775:Methylprednisolone
keywords: Carbon monoxide poisoning; Parkinsonism; cerebral blood flow; dementia; memantine hydrochloride; steroid pulse therapy