title: The frequency of anti-aquaporin-4 Ig g antibody in neuromyelitis optica and its spectrum disorders at a single tertiary referral center in malaysia.
abstract: Background. In the past the occurrence of neuromyelitis optica in Malaysia was thought to be uncommon and the frequency of anti-aquaporin-4 Ig G antibody was unknown. Objective. To evaluate the frequency of anti-aquaporin-4 Ig G antibody (Anti-AQP4 antibody) amongst patients with neuromyelitis optica (NMO) and its spectrum disorders (NMOSD) and the differences between the seropositive and seronegative groups. Methods. Retrospectively, 96 patients with NMO/high risk syndromes for NMOSD (HRS-NMOSD) were identified out of 266 patients with idiopathic inflammatory demyelinating disease from a single center hospital based registry. Anti-AQP4 seropositivity was found in 38/48 (79.2%) with NMO, 12/21 (57.1%) with brain involvement at high risk for NMOSD, 12/15 (80%) with transverse myelitis (i.e., 11/15 with relapsing transverse myelitis and one with monophasic transverse myelitis), and 3/7 (42.8%) with relapsing optic neuritis. Sixty-five out of 96 patients, that is, 67.7%, with NMO/HRS for NMOSD were seropositive. Seropositivity was significantly associated with female gender, a higher number of mean relapses, that is, 5.15 ± 4.42 versus 2.10 ± 1.68, longer length of spinal cord lesions, that is, 6.6 ± 4.9 versus 2.9 ± 2.5, vertebral bodies, higher EDSS, 4.5 ± 2.4 versus 2.4 ± 2.6, presence of paroxysmal tonic spasms, and blindness (unilateral/bilateral); P < 0.001. Longitudinally extensive cord lesions (contiguous or linear), presence of lesions in the cervical and thoracic regions, and involvement of the central gray matter or holocord regions on axial scans, were also significantly associated with seropositivity; P < 0.001. Conclusion. NMO and HRS for NMOSD are present in larger numbers than previously thought in Malaysia. More than 2/3rds are seropositive. Seropositive and seronegative NMO/NMOSD have differences that are useful in clinical practice.
authors.affiliation: Department of Neurology, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia.
authors.forename: Shanthi
authors.initials: S
authors.lastname: Viswanathan
authors.affiliation: Autoimmune Unit, Allergy & Immunology Research Centre, Institute for Medical Research (IMR), Kuala Lumpur, Malaysia.
authors.forename: Masita
authors.initials: M
authors.lastname: Arip
authors.affiliation: Autoimmune Unit, Allergy & Immunology Research Centre, Institute for Medical Research (IMR), Kuala Lumpur, Malaysia.
authors.forename: Norhazlin
authors.identifier: 0000-0002-8586-6756
authors.initials: N
authors.lastname: Mustafa
authors.affiliation: Autoimmune Unit, Allergy & Immunology Research Centre, Institute for Medical Research (IMR), Kuala Lumpur, Malaysia.
authors.forename: Jasbir S
authors.initials: JS
authors.lastname: Dhaliwal
authors.affiliation: Department of Radiology, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia.
authors.forename: Norzainie
authors.initials: N
authors.lastname: Rose
authors.affiliation: Department of Radiology, National University of Malaysia, Kuala Lumpur, Malaysia.
authors.forename: Sobri
authors.initials: S
authors.lastname: Muda
authors.affiliation: Department of Neurology, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia.
authors.forename: Santhi Datuk
authors.initials: SD
authors.lastname: Puvanarajah
authors.affiliation: Department of Neurology, Kuala Lumpur Hospital, Kuala Lumpur, Malaysia.
authors.forename: Mohammad Hanip
authors.initials: MH
authors.lastname: Rafia
authors.affiliation: Pharmacy Department, Universiti Malaya, Kuala Lumpur, Malaysia.
authors.forename: Mark Cheong
authors.initials: MC
authors.lastname: Wing Loong