Demyelinating neuropathies
Increase confidence through expert-backed testing
Autoimmune demyelinating neuropathies include several conditions — among them chronic inflammatory demyelinating polyneuropathy (CIDP), autoimmune nodopathy, Guillain-Barre syndrome (GBS), distal acquired demyelinating symmetric (DADS) neuropathy, chronic immune sensory polyradiculopathy (CISP), and multifocal motor neuropathy (MMN) — that share overlapping motor and/or sensory features with other peripheral neuropathies.
Used as an adjacent to nerve conduction study (NCS) and electromyography (EMG) studies, our testing can help physicians better understand the underlying etiology of a patient’s demyelinating neuropathy, which is important to accurately diagnose and treat patients.
Demyelinating neuropathies Test menu
Antibody evaluation
When NCS and EMG studies are suggestive of a demyelinating process, the presence of specific autoantibodies indicates that an underlying, misdirected immune response may be driving the demyelination. Our clinically validated antibody evaluation includes only those biomarkers that correlate with demyelinating neuropathies. Including wide-ranging, relevant antibodies with high clinical specificity minimizes unnecessary testing and the potential for false-positive results.
Key testing
Advantages
- Helps distinguish between different disease etiologies in patients with evidence of a demyelinating neuropathy with clinical presentation consistent with underlying autoimmune features.
- Assesses for the presence of seven antibodies specific to autoimmune demyelinating neuropathies that align with electrophysiological findings: neurofascin-155 IgG4, contactin-1 IgG, MAG IgM, and clinically relevant IgG and IgM antibodies targeting GQ1B, GD1B, and GM1 gangliosides.
- Results can inform prognosis and guide treatment decisions.
- Results report includes in-depth interpretive comments to provide meaningful guidance to ordering physicians.
- Helps eliminate the potential for false positives by minimizing the likelihood that antibody testing is performed in patients with low likelihoods of having the antibody.
Highlights
John Mills, Ph.D., and Divyanshu Dubey, M.B.B.S., explain how Mayo Clinic Laboratories' new test panel can distinguish among various potential causes of demyelinating neuropathies. Test results are important for managing these devastating autoimmune conditions.
chronic inflammatory demyelinating polyneuropathy
Frequently misdiagnosed, CIDP in most cases is highly responsive to first-line immunotherapy treatments, such as intravenous immunoglobin (IVIG). However, a subset of individuals with specific paranodal antibodies do not respond as well to these therapies. The presence of neurofascin 155 (NF155) IgG4 and contactin-1 (CNTN1) IgG indicates a unique disease etiology, with antibodies targeting the paranode. These patients have a relatively poor treatment response to IVIG. We’ve developed and validated a unique assay combination available exclusively at Mayo Clinic Laboratories.
Key testing
Advantages
- Evaluates for antibodies directed against NF155 and CNTN1, two common biomarkers associated with CIDP.
- Combination assay uses a fixed cell-based assay to measure antibodies directed against CNTN1 protein and live cell flow cytometry to identify antibodies directed against NF155. This offers higher clinical specificity than conventional testing methodologies.
Highlights
Divyanshu (Div) Dubey, M.B.B.S., describes Mayo Clinic Laboratories' new diagnostic test for CIDP, or chronic inflammatory demyelinating polyneuropathy. The new test detects two antibodies — NF155 and CNTN1 — to enhance diagnosis and guide treatment decisions. Often misdiagnosed, CIDP is treatable if detected early.
Sophisticated laboratory testing solved a medical riddle and finally got Jori Pearson back on his feet, doing what he loves.
myelin-associated glycoprotein
The presence of myelin-associated glycoprotein (MAG) antibodies is often linked to a rare demyelinating neuropathy with poor treatment response known as DADS neuropathy. In some cases, reaching a correct diagnosis through clinical and electrophysiological evaluation alone can be difficult due to overlapping features or when patient evaluation occurs later in the disease course. Incorporating MAG antibody testing into the diagnostic workup can help identify the correct diagnosis and exclude patients with treatable immune-mediated neuropathies.
Key testing
Advantages
- Utilizes a semi-quantitative ELISA platform and human MAG antigen with improved specificity to equip physicians with more accurate information.
- Consider MAG autoantibody testing in the following instances:
- Inconclusive electrodiagnostic studies.
- Presence of an IgM monoclonal protein (M-protein) and neuropathy.
- Suspicion of DADS neuropathy.
Highlights
John Mills, Ph.D., explains Mayo Clinic Laboratories’ approach to MAG antibody testing. The ELISA-based assay uses higher reference ranges and human MAG antigen to detect MAG antibodies, which are associated with a rare, hard-to-treat condition known as DADS neuropathy.
References
- Querol L, Nogales-Gadea G, Rojas-Garcia R, et al. Antibodies to contactin-1 in chronic inflammatory demyelinating polyneuropathy. Ann Neurol. 2013 Mar;73(3):370-80. doi:10.1002/ana.23794. Epub 2012 Dec 31. PMID: 23280477.
- Querol L, Nogales-Gadea G, Rojas-Garcia R, et al. Neurofascin IgG4 antibodies in CIDP associate with disabling tremor and poor response to IVIg. Neurology. 2014 Mar 11;82(10):879-86. doi:10.1212/WNL.0000000000000205. Epub 2014 Feb 12. PMID: 24523485; PMCID: PMC3959751.
- Ng JK, Malotka J, Kawakami N, et al. Neurofascin as a target for autoantibodies in peripheral neuropathies. Neurology. 2012 Dec 4;79(23):2241-8. doi:10.1212/WNL.0b013e31827689ad. Epub 2012 Oct 24. PMID: 23100406; PMCID: PMC3542349.
- Dubey D, Honorat JA, Shelly S. Contactin-1 autoimmunity: Serologic, neurologic, and pathologic correlates. Neurol Neuroimmunol Neuroinflamm. 2020 May 27;7(4):e771. doi:10.1212/NXI.0000000000000771. PMID: 32461352; PMCID: PMC7286654.
- Shelly S, Klein CJ, Dyck PJB, et al. Neurofascin-155 immunoglobulin subtypes: clinicopathologic associations and neurologic outcomes. Neurology. 2021 Dec 14;97(24):e2392-e2403. doi:10.1212/WNL.0000000000012932. Epub 2021 Oct 11. PMID: 34635556; PMCID: PMC8673722.