Neurophysiologic findings in early acute inflammatory demyelinating polyradiculoneuropathy

Background: Patients with early acute inflammatory demyelinating polyradiculoneuropathy (AIDP) may not meet the current neurophysiologic criteria. Objective: To document neurophysiologic findings in early AIDP. Methods: Clinical and neurophysiologic data from 38 AIDP patients, assessed within 10 days of symptom onset were reviewed. Results: In addition to absent H reflexes and abnormal F-wave responses in the acute stage of AIDP, abnormalities of blink reflexes, upper limb sensory responses abnormalities with spared sural responses, presence of distal CMAP dispersion, and A-waves were frequently observed. Established demyelinating neurophysiologic parameters were infrequently seen. Conclusions: Abnormalities of H reflexes and F responses were most frequently noted in early AIDP. Additionally, distal temporal dispersion, prolonged or absent blink reflexes, and A-waves were often present in the acute stage of AIDP when classic diagnostic criteria of AIDP were not satisfied. Significance: Neurophysiologic studies in early AIDP frequently reveal abnormalities that are not specific of primary demyelinating neuropathy. (C) 2004 Published by Elsevier Ireland Ltd. on behalf of International Federation of Clinical Neurophysiology.