title: Reappraisal of brain MRI features in patients with multiple sclerosis and neuromyelitis optica according to anti-aquaporin-4 antibody status.
abstract: Brain lesions are not uncommon in neuromyelitis optica (NMO) patients with anti-aquaporin-4 (AQP4) antibody; however, the appearance of these lesions is said to be different from that of those in Western patients with multiple sclerosis (MS). To clarify the similarities and dissimilarities of brain lesions in anti-AQP4 antibody-positive and -negative MS and NMO patients, we examined the presence of anti-AQP4 antibody in the sera of 148 consecutive patients fulfilling Poser's criteria for clinically definite MS, of whom 38 also met the revised NMO criteria, using an immunofluorescence method, and analyzed brain lesions by magnetic resonance imaging (MRI). Brain lesions fulfilling the Barkhof criteria were significantly more common in 121 patients without anti-AQP4 antibody than in 27 patients with anti-AQP4 antibody (57.0% vs. 33.3%, P=0.033), while the frequency of those that met the Paty criteria was not different between the two groups (74.4% vs. 73.5%). Ovoid lesions were detected more commonly in patients without anti-AQP4 antibody than in those with the antibody (72.3% vs. 48.2%, P=0.022). The anti-AQP4 antibody-positive patients had significantly more atypical brain lesions, such as extensive brain lesions, than the anti-AQP4 antibody-negative ones (18.5% vs. 1.7%, P=0.0023). Thus, although MS-like brain lesions are more common in anti-AQP4 antibody-negative patients than anti-AQP4 antibody-positive patients, approximately 30 to 50% of patients with anti-AQP4 antibody harbour brain MRI lesions indistinguishable from those present in typical MS patients, such as periventricular ovoid lesions, suggesting the existence of considerable overlap in brain MRI features between anti-AQP4 antibody-positive and -negative Asian patients. In the present study, NMO patients with brain lesions showed a significantly higher annualized relapse rate (P(corr)=0.017) and higher frequency of anti-AQP4 antibody (P(corr)<0.0001) than typical NMO patients without brain lesions, suggesting that development of brain lesions in NMO may reflect high disease activity and thus be a warning sign.
authors.affiliation: Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan. kira@neuro.med.kyushu-u.ac.jp
authors.forename: Takuya
authors.initials: T
authors.lastname: Matsushita
authors.forename: Noriko
authors.initials: N
authors.lastname: Isobe
authors.forename: Hua
authors.initials: H
authors.lastname: Piao
authors.forename: Takeshi
authors.initials: T
authors.lastname: Matsuoka
authors.forename: Takaaki
authors.initials: T
authors.lastname: Ishizu
authors.forename: Hikaru
authors.initials: H
authors.lastname: Doi
authors.forename: Katsuhisa
authors.initials: K
authors.lastname: Masaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Yoshiura
authors.forename: Ryo
authors.initials: R
authors.lastname: Yamasaki
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Ohyagi
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Kira
mesh_terms: D000328:Adult; D051401:Aquaporin 4 / Q000276:immunology*; D044466:Asian People; D001323:Autoantibodies / Q000032:analysis*; D001921:Brain / Q000473:pathology*; D005260:Female; D006801:Humans; D007564:Japan; D008279:Magnetic Resonance Imaging; D008297:Male; D009103:Multiple Sclerosis / Q000276:immunology* / Q000473:pathology*; D020528:Multiple Sclerosis, Chronic Progressive / Q000276:immunology / Q000473:pathology; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000276:immunology / Q000473:pathology; D009471:Neuromyelitis Optica / Q000276:immunology* / Q000473:pathology*; D012720:Severity of Illness Index
chemical_list: C496030:AQP4 protein, human; D051401:Aquaporin 4; D001323:Autoantibodies