CENTRAL-NERVOUS-SYSTEM INVOLVEMENT IN MULTIFOCAL DEMYELINATING NEUROPATHY WITH PERSISTENT CONDUCTION BLOCK

We report the case of a 27-year-old man treated for bilateral optic ne uritis 5 and 3 years before who within a few months developed sensorim otor disorders of the arms and legs characterized by asymmetric distri bution and distal prominence. In addition to sensorimotor defects, whi ch were particularly marked in the left arm and right leg, clinical ex amination showed nearly generalized areflexia. Electrophysiological st udies revealed a multifocal neuropathy with persistent distal and prox imal conduction blocks associated with a considerable slowing of motor nerve conduction, as well as central nervous system involvement indic ated by motor-, somatosensory-, and visual-evoked potentials. CSF anal ysis showed a mildly elevated protein level; anti-GM(1) activity was n egative. Sural nerve biopsy revealed onion-bulb-like formations, and c erebral MRI showed a small, isolated, and aspecific high signal for wh ite matter. First described by Lewis and Sumner in 1982, multifocal ne uropathy with persistent conduction blocks may be associated with cent ral demyelination. Our case is compared with 3 similar ones in the lit erature, and the favorable effects of steroid therapy are emphasized. (C) 1994 John Wiley & Sons, Inc.