Anti-MAG Neuropathy

1. Ade Wijaya, MD – October 2023

2.  Introduction: Myelin-Associated Glycoprotein
(MAG)
 Clinical presentation
 Diagnosis
 Pathogenesis
 Treatment
 Summary

3.  Constituent of myelin in the CNS and PNS
Trapp BD. Myelin‐Associated Glycoprotein Location and Potential Functions a. Annals of the New York Academy of Sciences. 1990 Nov;605(1):29-43.
Steck AJ. Anti-MAG neuropathy: From biology to clinical management. Journal of Neuroimmunology. 2021 Dec 15;361:577725.

4.  Chronic, slowly progressive large-fiber
sensory- motor polyneuropathy, usually
affecting lower extremities initially
 Sensory ataxia with gait imbalance
 Some patients develop tremors in hands and
fingers enhanced by action; intention tremor
Steck AJ. Anti-MAG neuropathy: From biology to clinical management. Journal of Neuroimmunology. 2021 Dec 15;361:577725.

5.  Most common in elderly males
 Neurological signs appear insidiously, spare
the cranial nerves, and worsen slowly over
one or two decades
 In advanced cases: muscle weakness,
wasting, and severe ataxia
 Pain, cramps, paresthesia; disesthesia
 Progress slowly but develop significant
disability over time
Rajabally YA, Delmont E, Hiew FL, Aubé‐Nathier AC, Grapperon AM, Cassereau J, Attarian S. Prevalence, correlates and impact of pain and cramps in anti‐MAG neuropathy: a
multicentre European study. European journal of neurology. 2018 Jan;25(1):135-41.
Steck AJ. Anti-MAG neuropathy: From biology to clinical management. Journal of Neuroimmunology. 2021 Dec 15;361:577725.

6.  Anti-MAG antibody tests
 Electrophysiology: demyelinating
polineuropaty
Steck AJ. Anti-MAG neuropathy: From biology to clinical management. Journal of Neuroimmunology. 2021 Dec 15;361:577725.

7. Kawagashira Y, Koike H, Tomita M, Morozumi S, Iijima M, Nakamura T, Katsuno M, Tanaka F, Sobue G. Morphological progression of myelin abnormalities in IgM-monoclonal
gammopathy of undetermined significance anti-myelin-associated glycoprotein neuropathy. Journal of Neuropathology & Experimental Neurology. 2010 Nov 1;69(11):1143-57.
Kawagashira Y, Koike H, Ohyama K, Hashimoto R, Iijima M, Adachi H, Katsuno M, Chapman M, Lunn M, Sobue G. Axonal loss influences the response to rituximab treatment in
neuropathy associated with IgM monoclonal gammopathy with anti-myelin-associated glycoprotein antibody. Journal of the Neurological Sciences. 2015 Jan 15;348(1-2):67-73

8. Steck AJ. Anti-MAG neuropathy: From biology to clinical management. Journal of Neuroimmunology. 2021 Dec 15;361:577725.

9.  Autoimmune demyelinating neuropathy
 Antibody against MAG
 Diagnosis: clinical; antibody;
electrophysiology
 B cells depleting therapies are main
therapeutical mode of treatment
 New treatment modalities include inhibitors
or antigen-specific immunotherapy.