J Clin Neurol.  2024 Jan;20(1):50-58. 10.3988/jcn.2023.0127.

Therapeutic Outcomes and Electrophysiological Biomarkers in Anti-Myelin-Associated Glycoprotein Neuropathy: A Multicenter Cohort Study in South Korea

Affiliations
  • 1Department of Translational Medicine, Seoul National University College of Medicine, Seoul, Korea
  • 2Department of Neurology, Seoul National University Hospital, Seoul, Korea
  • 3Department of Neurology, Yonsei University College of Medicine, Seoul, Korea
  • 4Department of Neurology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
  • 5Department of Neurology, Korea University Anam Hospital, Korea University College of Medicine, Seoul, Korea
  • 6Department of Neurology, Nowon Eulji Medical Center, Seoul, Korea
  • 7Department of Neurology, Kosin Medical University Hospital, Busan, Korea
  • 8Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea
  • 9Department of Neurology, Seoul National University Boramae Medical Center, Seoul, Korea
  • 10Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, Korea

Abstract

Background and Purpose
Unlike other immune-mediated neuropathies, anti-myelin-associated glycoprotein (MAG) neuropathy is often refractory to immunotherapy. It is necessary to compare the relative efficacies of various immunotherapies and develop objective biomarkers in order to optimize its clinical management.
Methods
This study recruited 91 patients with high anti-MAG antibody titers from 7 tertiary hospitals in South Korea. We analyzed the baseline characteristics, therapeutic outcomes, and nerve conduction study (NCS) findings of 68 patients and excluded 23 false positive cases.
Results
The rate of positive responses to treatment was highest using zanubrutinib (50%) and rituximab (36.4%), followed by corticosteroids (16.7%), immunosuppressants (9.5%), intravenous immunoglobulin (5%), and plasma exchange (0%). Disability and weakness were significantly associated with multiple NCS parameters at the time of diagnosis, especially distal compound muscle action potential (CMAP) amplitudes. Moreover, the longitudinal trajectory of the average CMAP amplitudes paralleled the clinical courses, with a 16.2 percentile decrease as an optimal cutoff for predicting a clinical exacerbation (area under the receiver operating characteristic curve=0.792).
Conclusions
Our study supports the use of NCS as an objective marker for estimating disease burden and tracking clinical changes in patients with anti-MAG neuropathy. We have described the beneficial effects of rituximab and a new drug, zanubrutinib, compared with conventional immunotherapies.

Keyword

anti-MAG neuropathy; immunotherapy; efficacy; biomarker; nerve conduction study
Full Text Links
  • JCN
Actions
Cited
CITED
export Copy
Close
Share
  • Twitter
  • Facebook
Similar articles
Copyright © 2024 by Korean Association of Medical Journal Editors. All rights reserved.     E-mail: koreamed@kamje.or.kr