The diagnostic utility of determining anti-GM1: GalC complex antibodies in multifocal motor neuropathy: a validation study

Background: Multifocal motor neuropathy (MMN) is associated with IgM antibodies to GM1 ganglioside. The importance of the lipid milieu that might facilitate or inhibit antibody binding to GM1 in immunoassays is well recognised. Existing studies, using a range of different approaches, generally concur that anti-GM1 IgM antibody detection rates are improved by the addition of galactocerebroside (GalC) to the GM1 assay. Objective: The current study sought to formally evaluate the clinical utility of the GM1:GalC complex assay in the diagnosis of MMN. Methods: Anti-GM1 and -GM1:GalC antibodies were examined using ELISA and glycoarray (dot blot) in a fully blinded study design, consisting of 100 MMN patients, 100 ALS cases and 100 healthy controls. Results: The detection of anti-GM1 Abs using glycoarray was 67% sensitive and 85% specific. The addition of GalC to GM1, (1:1 weight to weight ratio), increased the sensitivity to 81% , whilst dropping specificity to 80% . Increasing the GalC content to a 1:5 ratio (or higher) further decreased specificity, and in doing so limited the usefulness of the GM1:GalC assay to the level of GM1 alone. The addition of GalC to the ELISA method also significantly increased sensitivity compared with GM1 alone, albeit with a significant decrease in specificity. Conclusions: This study indicates that the GM1:GalC assay is an advantageous assay adaptation for detecting anti-GM1 antibodies in MMN, using either glycoarray or ELISA, and warrants introduction into clinical diagnostic practice

Anti-NF155 chronic inflammatory demyelinating polyradiculoneuropathy strongly associates to HLA-DRB15

Background: The aim of the research is to study the human leukocyte antigen (HLA) class II allele frequencies in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) associated with anti-neurofascin 155 (NF155) antibodies. Methods: Thirteen anti-NF155+ and 35 anti-NF155 negative (anti-NF155neg) CIDP patients were included in a casecontrol study. The frequencies of the DRB1 HLA allele were analyzed in all patients while DQ frequencies were only studied in patients sharing the DRB1*15 allele. In silico HLA-peptide binding and NF155 antigenicity, predictions were performed to analyze overlap between presented peptides and antigenic regions. Results: DRB1*15 alleles (DRB1*15:01 and DRB1*15:02) were present in 10 out of 13 anti-NF155+ CIDP patients and in only 5 out of 35 anti-NF155neg CIDP patients (77 vs 14%; OR = 20, CI = 4.035 to 99.13). DRB1*15 alleles appeared also in significantly higher proportions in anti-NF155+ CIDP than in normal population (77 vs 17%; OR = 16.9, CI = 4.434 to 57. 30). Seven anti-NF155+ CIDP patients (53%) and 5 anti-NF155neg CIDP patients had the DRB1*15:01 allele (OR = 7, p = 0.009), while 3 anti-NF155+ CIDP patients and none of the anti-NF155neg CIDP patients had the DRB1*15:02 allele (OR = 23.6, p = 0.016). In silico analysis of the NF155 peptides binding to DRB1*15 alleles showed significant overlap in the peptides presented by the 15:01 and 15:02 alleles, suggesting functional homology. Conclusions: DRB1*15 alleles are the first strong risk factor associated to a CIDP subset, providing additional evidence that anti-NF155+ CIDP patients constitute a differentiated disease within the CIDP syndrome

Evaluation de la prise en charge des crises myasthéniques en réanimation médicale au CHU de Nice

NICE-BU Médecine Odontologie (060882102) / SudocSudocFranceF

Le cyclophosphamide en traitement de fond des scléroses en plaques de type progressif (thèse)

NICE-BU Médecine Odontologie (060882102) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Monitoring the short-term effect of intravenous immunoglobulins in multifocal motor neuropathy using motor unit number index

International audienc

Motor unit number index: A potential electrophysiological biomarker for pediatric spinal muscular atrophy

International audienc

Are electrophysiological features related to disability in patients with anti-MAG neuropathy?

International audienc

Shoulder palsy following SARS-CoV-2 infection: two cases o typical Parsonage-Turner syndrome

BACKGROUND AND PURPOSE: Coronavirus disease 2019 (COVID‐19) is now known to cause neurological complications in both the central and the peripheral nervous system. Two new cases of typical neuralgic amyotrophy or Parsonage–Turner (PT) syndrome following coronavirus 2 infection (SARS‐CoV‐2) are reported here with explicit electrophysiological and imaging pathological features, underlining the possible association between COVID‐19 and PT syndrome. CASE REPORTS: Case 1 was a 45‐year‐old schoolteacher presenting with acute pain in the right shoulder a few days after SARS‐CoV‐2 infection, with shoulder abduction and elbow flexion weakness. Needle electromyography showed a decrease in motor unit recruitment in the biceps brachii, and plexus magnetic resonance imaging (MRI) revealed a hyperintense signal involving the right C6 root and the superior truncus of the brachial plexus. Case 2 was a 21‐year‐old man hospitalized for dyspnea secondary to SARS‐CoV‐2 infection. Ten days after symptom onset, he presented right shoulder pain with difficulty in raising his right arm, revealing an isolated deficit of the serratus major muscle with a right scapula winging. Electrophysiological evaluation exhibited an isolated involvement of the long thoracic nerve with a neurogenic recruitment pattern in the serratus major muscle. Plexus MRI displayed a thickening and hyperintense signal involving the right long thoracic nerve. DISCUSSION: Parsonage–Turner syndrome triggered by SARS‐CoV‐2 seems to present clinical, electrophysiological and MRI characteristics similar to classic para‐infectious PT syndrome, including the time frame between viral infection and neurological symptom onset. Conclusion SARS‐CoV‐2 might be a new infectious trigger of PT syndrome

Detection of proximal conduction blocks using a triple stimulation technique improves the early diagnosis of Guillain-Barre syndrome

Objective: Current diagnostic electrophysiological criteria can miss the early stages of Guillain-Barre syndrome (GBS). We evaluated the diagnostic efficiency of the triple stimulation technique (TST) in highlighting proximal conduction blocks (CBs) in patients who do not meet the electrophysiological criteria for GBS. Methods: All patients with a diagnosis of clinical GBS referred to our center between September 2014 and January 2016 were included in the study. For patients who did not fulfill the electrophysiological criteria of GBS, we performed the TST examination. Results: Among the 44 included patients, 86% fulfilled the electrophysiological criteria of GBS during the initial nerve conduction study (NCS). The six remaining patients had proximal CBs revealed by TST examination. Therefore, a combination of a conventional NCS and the TST allowed 100% of the patients to be electrophysiologically diagnosed. Conclusions: TST is useful for the diagnosis of GBS in association with NCS, particularly in the early stages of the disease. (C) 2017 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved

Detection of proximal conduction blocks using a triple stimulation technique improves the early diagnosis of Guillain-Barre syndrome

Objective: Current diagnostic electrophysiological criteria can miss the early stages of Guillain-Barre syndrome (GBS). We evaluated the diagnostic efficiency of the triple stimulation technique (TST) in highlighting proximal conduction blocks (CBs) in patients who do not meet the electrophysiological criteria for GBS. Methods: All patients with a diagnosis of clinical GBS referred to our center between September 2014 and January 2016 were included in the study. For patients who did not fulfill the electrophysiological criteria of GBS, we performed the TST examination. Results: Among the 44 included patients, 86% fulfilled the electrophysiological criteria of GBS during the initial nerve conduction study (NCS). The six remaining patients had proximal CBs revealed by TST examination. Therefore, a combination of a conventional NCS and the TST allowed 100% of the patients to be electrophysiologically diagnosed. Conclusions: TST is useful for the diagnosis of GBS in association with NCS, particularly in the early stages of the disease. (C) 2017 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved