Clinical and Electrodiagnostic Findings in Anti-myelin-Associated Glycoprotein Antibody Polyneuropathy: A Single...

Anti-myelin-associated glycoprotein (MAG) polyneuropathy has been described as a progressive distal, sensorimotor, demyelinating polyneuropathy associated with immunoglobulin M paraprotein and low terminal latency index (TLI) on electrodiagnostic testing. We describe the features of patients with MAG antibody polyneuropathy at a single academic center.

A retrospective search of the electronic medical record identified patients with high titer anti-MAG antibody polyneuropathy. Demographic characteristics, clinical features, and nerve conduction studies were reviewed. TLI was calculated for tested nerves.

Sixteen patients were identified. Mean age was 75 years. Sixty-nine percent were male. Twenty-five percent of patients had Waldenstrom macroglobulinemia. Half of patients had demyelinating features on nerve conduction studies. Mean TLI for the median, ulnar, fibular, and tibial nerves was 0.36, 0.41, 0.37, and 0.39 respectively. Average TLI for all nerves was 0.38. All but 1 patient received treatment-most often rituximab or intravenous immunoglobulin. Clinical improvement was noted in 56% of treated patients.

This cohort of MAG antibody neuropathy patients had greater clinical variability than typically described.