Multifocal Motor Neuropathy: A Narrative Review

Area of Science:

• Neurology
• Immunology
• Autoimmune Disorders

Background:

• Multifocal motor neuropathy (MMN) is a rare autoimmune polyneuropathy targeting motor nerve fibers.
• It typically presents as progressive, asymmetric weakness, predominantly in distal upper extremities of middle-aged adults.

Purpose of the Study:

• To summarize the key features, diagnostic methods, and current treatment landscape of MMN.
• To highlight the need for improved long-term therapeutic strategies for MMN.

Main Methods:

• Review of clinical presentation, electrodiagnostic findings, and imaging techniques in MMN.
• Analysis of current treatment efficacy and limitations, focusing on immunoglobulin therapy.
• Exploration of emerging therapeutic targets, such as complement inhibition.

Main Results:

• MMN is characterized by motor conduction blocks and asymmetric weakness.
• Immunoglobulin therapy is effective but often insufficient for long-term disease control.
• Elevated anti-GM1 antibodies are present in less than half of patients.

Conclusions:

• MMN diagnosis relies on clinical and electrodiagnostic findings, with imaging aiding in complex cases.
• Current treatments provide symptomatic relief but do not halt long-term progression.
• Complement inhibition represents a promising future therapeutic avenue for MMN.