Relapsing antibody-negative patients with features of neuromyelitis optica spectrum disorders: Differences in N-acetylaspartate level in the cervical spinal cord indicate distinct underlying processes. (December 2022)

• Record Type: Journal Article
• Authors: Kossowski, Bartosz; Kong, Yazhuo; Klimiec-Moskal, Elżbieta; Emir, Uzay; Palace, Jacqueline; Juryńczyk, Maciej
• Is Part Of: Multiple sclerosis. Volume 28:Number 14(2022)
• Page Start: 2221
• Page End: 2230
• Publication Date: 2022-12
• Subjects: Neuromyelitis optica -- MRI -- multiple sclerosis; Central nervous system -- Diseases -- Periodicals; Myelin sheath -- Diseases -- Periodicals; Inflammation -- Periodicals; Multiple sclerosis -- Periodicals; Central Nervous System Diseases -- Periodicals; Demyelinating Diseases -- Periodicals; Inflammation -- Periodicals; Multiple Sclerosis -- Periodicals; Système nerveux central -- Maladies -- Périodiques; Gaine de myéline -- Maladies -- Périodiques; Inflammation (Pathologie) -- Périodiques; Sclérose en plaques -- Périodiques; Electronic journals; 616.834005
• DOI: 10.1177/13524585221115304
• Languages: English
• ISSNs: 1352-4585

Abstract

Background: Due to lack of biomarkers, antibody-negative patients with features of neuromyelitis optica spectrum disorders (NMOSD) are among the most challenging to diagnose and treat. Using unsupervised clustering, we recently identified 'MS-like', 'spinal MS-like', 'classic NMOSD-like' and 'NMOSD-like with brain involvement' subgroups in this cohort. Objective: We used magnetic resonance spectroscopy (MRS) to examine differences in the level of key metabolites in the spinal cord between the four identified subgroups. Methods: Twenty-five relapsing antibody-negative patients with NMOSD features classified by the unsupervised algorithm to one of the subgroups underwent a prospective cervical spinal cord MRS. Spectra from 16 patients fulfilled quality criteria and were included in the analysis. Results: Total N -acetylaspartate (tNAA), but not total choline (tCho) or myo-inositol (Ins), was significantly different between the four subgroups ( p = 0.03). In particular, tNAA was 47.8% lower in the 'MS-like' subgroup as compared with the 'classic NMOSD-like' subgroup ( p = 0.02). While we found a negative overall correlation between tNAA and disability score ( r = –0.514, p = 0.04) in the whole cohort, the disability score did not differ significantly between the subgroups to explain subgroup differences in tNAA level. Conclusions: Significant differences in the cervical spinal cord tNAA measurements confirm that the previously identified clinico-radiologic subgroups contain patients with distinct underlying disease processes.