Anti-MAG Neuropathy

Anti-myelin-associated glycoprotein (MAG) neuropathy is a rare autoimmune neuropathy that preferentially affects the myelin of distal fibers. This distal demyelination and secondary axon loss lead to its characteristic clinical features of distal sensory loss and weakness, upper limb tremor, and ataxia, leading to significant disability for the patient. Diagnosis is predicated on its distinct electrodiagnostic and serological profile of distally accentuated demyelination and high IgM anti-MAG antibody titers. Accurate diagnosis of anti-MAG neuropathy is critical, as standard CIDP therapies do not work, but some novel treatments like Bruton tyrosine kinase inhibitors may prove effective. Currently, rituximab is the most frequently used treatment, despite current evidence showing benefit in only a subset of patients. This review highlights the value of gait analysis in the clinical and research assessment of anti-MAG neuropathy, using existing quality of life-based data. The unique pathophysiology and clinical features of anti-MAG neuropathy create specific rehabilitation challenges, making awareness of this disorder critical for electromyographers and those treating neuropathies in all settings.