Motor-dominant chronic inflammatory demyelinating polyneuropathy.

We reviewed the clinical, electrophysiological an laboratory findings, plus the therapeutics and evolution of patients with motor-dominant Chronic inflammatory demyelinating polyneuropathy (CIDP) and compared them with those of other CIDP patients. Among 12 consecutive CIDP patients, we identified five patients with motor-dominant CIDP. The five patients with motor-dominant CIDP initially presented with weakness of the upper limbs. Cervical magnetic resonance imaging (MRI) examinations of the patients with motor-dominant CIDP showed that the most affected lesions are the cervical nerve roots and brachial plexus. The clinical course of these patients was relapsing-remitting, and they improved markedly after treatment by intravenous immunoglobulin (IVIg) infusion or plasmapheresis. However, they did not improve in response to corticosteroid therapy during the acute phase of relapses. The relapses frequently occurred within 2 years, but rarely occurred after that. The score in the modified Rankin disability scale (mRDS) at the last follow-up period was statistically lower for the patients with motor-dominant CIDP than for the other CIDP patients (P < 0.002). The characteristic clinical features, responsiveness to treatment, and prognosis suggest that motor-dominant CIDP is a distinct subtype of CIDP, with a specific immunological background. Repeated IVIg therapy is required to maintain the motor functions of patients with motor-dominant CIDP. We consider that treatment for recurrence prevention as an alternative to IVIg therapy is very important for patients with motor-dominant CIDP.