Background: Several diagnostic criteria for multifocal motor neuropathy (MMN) have been proposed in recent years, and a beneficial effect of intravenous immunoglobulin (IVIg) and various other immunomodulatory drugs has been suggested in several trials and uncontrolled studies.
Objectives: The aim of this guideline was to prepare consensus guidelines on the definition, investigation, and treatment of MMN.
Methods: Disease experts and a representative of patients considered references retrieved from MEDLINE and the Cochrane Library in July 2004 and prepared statements that were agreed in an iterative fashion.
Recommendations: The Task Force agreed on good practice points to define clinical and electrophysiological diagnostic criteria for MMN and investigations to be considered. The principal recommendations and good practice points were as follows: (1) IVIg (2 g/kg given over 2-5 days) should be considered as the first line of treatment (level A recommendation) when disability is sufficiently severe to warrant treatment; (2) corticosteroids are not recommended (good practice point); (3) if initial treatment with IVIg is effective, repeated IVIg treatment should be considered (level C recommendation). The frequency of IVIg maintenance therapy should be guided by the individual response (good practice point). Typical treatment regimens are 1 g/kg every 2-4 weeks or 2 g/kg every 4-8 weeks (good practice point); (4) if IVIg is not (or not sufficiently) effective, then immunosuppressive treatment may be considered. Cyclophosphamide, cyclosporine, azathioprine, interferon-beta1a, or rituximab are possible agents (good practice point); and (5) toxicity makes cyclophosphamide a less desirable option (good practice point).