ROOT STIMULATION IMPROVES THE DETECTION OF ACQUIRED DEMYELINATING POLYNEUROPATHIES

Thirty-one patients with a presentation compatible with an acquired de myelinating polyradiculoneuropathy were prospectively evaluated for pr oximal conduction block using root stimulation (RS) of cervical and/or lumbar roots. These same techniques were applied to 78 controls (40 p athological). Proximal conduction block was noted in 20/31 cases and n one of the controls. Only 7 of 31 cases met published demyelinating cr iteria. Intravenous immune globulin therapy was completed by 21/31 pat ients and 20/21 responded. RS is superior to published electrophysiolo gic criteria for identifying demyelinating polyneuropathies and predic ting who will respond to treatment. RS should be performed in all pati ents suspected of having an acquired demyelinating polyneuropathy when traditional nerve conduction studies criteria are nondiagnostic. RS r eliably predicts those likely to respond to immunosuppressive therapy. (C) 1998 John Wiley & Sons, Inc.