Multifocal motor neuropathy.

In 1982 Lewis et all reported five patients with a chronic, asymmetric, motor and sensory neuropathy more pro- nounced in the upper than the lower limbs. This was electrophysiologically characterised by the presence of persistent multifocal partial conduction blocks in motor but not sensory nerves. The neuropathy improved in two patients after treatment with steroids and was considered by the authors to be a "multifocal" variant of chronic inflammatory demyelinating polyneuropathy (CIDP). Between 1985 and 1986 Parry and Clark,2 Roth et al,3 and Chad et a14 almost simultaneously first reported four patients in whom the presence of persistent multifocal partial motor conduction blocks was associated with a chronic, asymmetric, pure motor neuropathy without (or with minimal) sensory impairment. Since then at least 120 patients have been reported2-25 with this form of motor neuropathy, which has been variably related to CIDP357 or motor neuron disease,4 68 10 and is presently known as multifocal motor neuropathy.6 26