Chronic sensorimotor polyradiculopathy with antibodies to P2: an electrophysiological and immunoproteomic analysis.

Abstract

In this study we report a patient with chronic progressive sensory ataxia, proximal weakness, immunoglobulin M (IgM) monoclonal gammopathy, and elevated protein levels in the cerebrospinal fluid, who showed a good response to prednisone. Electrophysiological study disclosed abnormalities predominantly of late responses (F waves and H reflexes), with no evidence of demyelination in the peripheral nerves, suggesting motor and preganglionic sensory nerve roots as the site of the lesion. An immune-mediated pathogenesis was considered and, to identify possible target antigens, we performed bidimensional electrophoresis and a Western blot study. Based on the suspected lesion site, we used human anterior and posterior root extracts. We identified IgM reactivity against peripheral nerve myelin protein P2. Enzyme-linked immunosorbent assay confirmed IgM reactivity toward one synthetic peptide from P2. To our knowledge, reactivity against P2 has not been reported previously in a paraproteinemic neuropathy. Furthermore, we demonstrated that bidimensional electrophoresis and Western blot of the tissue involved, as determined by clinical and electrophysiological studies, may be useful to establish clinical-immunological correlations in paraproteinemic neuropathies.

• Authors: Ricard Rojas-Garcia, Eduard Gallardo, Carolina De La Torre, Lara Sanvito, Isabel Illa
• Journal: Muscle & nerve (Muscle Nerve) Vol. 38 Issue 1 Pg. 933-8 (Jul 2008) ISSN: 0148-639X [Print] United States
• PMID: 18508345 (Publication Type: Case Reports, Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: (c) 2008 Wiley Periodicals, Inc.

Chemical References

• Anti-Inflammatory Agents
• Myelin P2 Protein
• Nerve Tissue Proteins
• Prednisone

Topics

• Aged
• Anti-Inflammatory Agents (therapeutic use)
• Blotting, Western
• Chronic Disease
• Electrophoresis, Gel, Two-Dimensional
• Electrophysiology
• Enzyme-Linked Immunosorbent Assay
• Humans
• Male
• Myelin P2 Protein (genetics, immunology)
• Nerve Tissue Proteins (biosynthesis, genetics)
• Polyradiculopathy (genetics, immunology, physiopathology)
• Prednisone (therapeutic use)
• Proteomics
• Spinal Nerve Roots (pathology)