title: Central nervous system inflammatory demyelinating disorders among Hong Kong Chinese.
abstract: Classical multiple sclerosis (CMS) and neuromyelitis optica spectrum disorders (NMOSD) are distinct central nervous system inflammatory demyelinating disorders (CNS IDD). Early diagnosis of CNS IDD is important as appropriate immunotherapies to optimize prognosis. We studied the diagnoses of CNS IDD among Hong Kong Chinese in a hospital-based setting. Consecutive Chinese patients who presented to our hospital with clinically isolated syndrome and subsequently diagnosed to have CNS IDD from 1980 to 2010 were reviewed. Patients with known diagnosis of CNS IDD referred for further care were excluded. Serial sera were assayed for aquaporin-4 autoantibodies (AQP4 Ab), at least 3 assays within 2-5years. A total of 210 patients diagnosed to have CNS IDD with disease duration of at least 2years were studied. Among 198 patients with serial sera available, 40 (20.2%, 20 had NMO and 20 other NMOSD) were AQP4 Ab-positive. Four patients who were AQP4 Ab-negative on the initial assay converted to AQP4 Ab-positive on repeated assays. The diagnoses of 210 patients were CMS in 88 (41.9%), NMOSD 47 (22.4%, 27 NMO, 20 other NMOSD), single attack of myelitis 23 (11.0%), single attack of optic neuritis 21 (10.0%), relapsing myelitis 10 (4.8%), acute disseminated encephalomyelitis (ADEM) 9 (4.3%), relapsing optic neuritis in 6 (2.9%), opticospinal multiple sclerosis 3 (1.4%) and single attack of brainstem encephalitis 3 (1.4%). Compared to CMS, NMOSD patients had older onset age, lower frequencies of brain MRI abnormalities and CSF OCB, higher frequency of LETM, higher CNS inflammation attack frequency in the first 2years, worse clinical outcome with higher EDSS score and mortality rate. This hospital-based study suggests that CMS (41.9%) and NMOSD (22.4%) are the most common CNS IDD among Hong Kong Chinese. NMOSD has worse clinical outcome than CMS. Detection of AQP4 Ab facilitates early diagnosis and prompts immunotherapies of NMOSD.
authors.affiliation: University Department of Medicine, Queen Mary Hospital, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong; Neuroimmunology and Neuroinflammation Research Laboratory, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong; Research Center of Heart, Brain, Hormone and Healthy Aging, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong. Electronic address: koonho@hkucc.hku.hk.
authors.forename: K H
authors.initials: KH
authors.lastname: Chan
authors.forename: R
authors.initials: R
authors.lastname: Lee
authors.forename: J C Y
authors.initials: JC
authors.lastname: Lee
authors.forename: A C T
authors.initials: AC
authors.lastname: Tse
authors.forename: S Y Y
authors.initials: SY
authors.lastname: Pang
authors.forename: G K K
authors.initials: GK
authors.lastname: Lau
authors.forename: K C
authors.initials: KC
authors.lastname: Teo
authors.forename: P W L
authors.initials: PW
authors.lastname: Ho
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D002648:Child; D015331:Cohort Studies; D020278:Demyelinating Autoimmune Diseases, CNS / Q000453:epidemiology / Q000276:immunology / Q000473:pathology*; D005260:Female; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D007249:Inflammation / Q000453:epidemiology / Q000276:immunology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000453:epidemiology / Q000276:immunology / Q000473:pathology*; D009471:Neuromyelitis Optica / Q000453:epidemiology / Q000276:immunology / Q000473:pathology*; D055815:Young Adult
keywords: Aquaporin-4 autoantibodies; Classical multiple sclerosis; Inflammatory demyelinating disorders; Neuromyelitis optica spectrum disorders