Multifocal motor neuropathy

Lancet Neurol. 2005 May;4(5):309-19. doi: 10.1016/S1474-4422(05)70074-0.


Multifocal motor neuropathy (MMN) is an immune-mediated disorder characterised by slowly progressive, asymmetrical weakness of limbs without sensory loss. The clinical presentation of MMN mimics that of lower-motor-neuron disease, but in nerve-conduction studies of patients with MMN motor-conduction block has been found. By contrast with chronic inflammatory demyelinating polyneuropathy, treatment with prednisolone and plasma exchange is generally ineffective in MMN and even associated with clinical worsening in some patients. Of the immunosuppressants, cyclophosphamide has been reported as effective but only anecdotally. Various open trials and four placebo-controlled trials have shown that treatment with high-dose intravenous immunoglobulin leads to improvement of muscle strength in patients with MMN. Although clinical, pathological, imaging, immunological, and electrophysiological studies have improved our understanding of MMN over the past 15 years, further research is needed to elucidate pathogenetic disease mechanisms in the disorder.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Clinical Trials as Topic / statistics & numerical data
  • Diagnosis, Differential
  • Humans
  • Immunoglobulins, Intravenous / therapeutic use
  • Immunosuppressive Agents / therapeutic use
  • Motor Neuron Disease / diagnosis
  • Motor Neuron Disease / physiopathology*
  • Motor Neuron Disease / therapy
  • Muscle Weakness / drug therapy
  • Muscle Weakness / immunology
  • Muscle Weakness / physiopathology
  • Neural Conduction / immunology
  • Peripheral Nervous System Diseases / diagnosis
  • Peripheral Nervous System Diseases / physiopathology*
  • Peripheral Nervous System Diseases / therapy
  • Polyradiculoneuropathy / diagnosis
  • Polyradiculoneuropathy / physiopathology*
  • Polyradiculoneuropathy / therapy
  • Treatment Outcome


  • Immunoglobulins, Intravenous
  • Immunosuppressive Agents