48. Cranial nerve involvement as a unusual presentation of multifocal motor neuropathy

Abstract

Multifocal motor neuropathy (MMN) with conduction block is an acquired immune-mediated demyelinating neuropathy. The diagnosis of MMN is based on clinical, laboratory, and electrophysiological characteristics. The classic clinical features is characterized by slowly progressive, asymmetric, distal weakness, without objective loss of sensation. We report a 68 years Caucasic male, who exhibited diplopia and unilateral ptosis as presenting signs. The electrodiagnostic studies showed conduction block with reduction in the amplitude and area of the compound muscle action potential (CMAP) in the absence of abnormal temporal dispersion in left median, ulnar and peroneal nerves bilaterally, without sensory abnormalities.Titers of anti-GM1 antibodies were elevated. Treatment with intravenous immunoglobulin resulted in a fast electrodiagnostic improvement, with completely clinical recovery.