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Author

Jean Neil

Bio: Jean Neil is an academic researcher from University of Paris. The author has contributed to research in topics: IgM Monoclonal Gammopathy & Peripheral neuropathy. The author has an hindex of 7, co-authored 15 publications receiving 2073 citations.

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Journal ArticleDOI
TL;DR: This is the first study providing evidence for Zika virus infection causing Guillain-Barré syndrome, and because Zika virus is spreading rapidly across the Americas, at risk countries need to prepare for adequate intensive care beds capacity to manage patients with Guillay-B Barré syndrome.

1,925 citations

Journal ArticleDOI
01 Sep 2004-Brain
TL;DR: In some of the patients in this study, LSS evolved into a more diffuse neuropathy sharing similarities with CIDP, while others had a clinical course characterized by a striking multifocal neuropathy, which suggests underlying mechanisms different from C IDP.
Abstract: Lewis-Sumner syndrome (LSS) is a dysimmune peripheral nerve disorder, characterized by a predominantly distal, asymmetric weakness mostly affecting the upper limbs with sensory impairment, and by the presence of multifocal persistent conduction blocks. The nosological position of this neuropathy in relation to multifocal motor neuropathy (MMN) and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is still debated. We report the clinical, biological and electrophysiological features, the course and the response to treatment in 23 LSS patients. The initial symptoms started in the distal part of an upper limb in 70% of patients. They were sensorimotor in 65% and purely sensory in 35% of patients. A cranial nerve involvement was observed in 26% of patients and a distal limb amyotrophy in 52%. The CSF protein level was normal in 67% of patients and mildly elevated in the remainder. None had serum anti-GM1 antibodies. There were multiple motor conduction blocks (average of 2.87/patient), predominantly located in the forearm, whereas demyelinating features outside the blocked nerves were rare. Abnormal distal sensory potentials were found in 87% of patients. The electrophysiological pattern suggests a very focal motor fibre demyelination sparing the nerve endings, whereas sensory fibre involvement was widespread. The course was chronic progressive in 71% of patients and relapsing-remitting in the others. During the follow-up study (median duration of 4 years), half of the patients progressed with a multifocal pattern and the distribution of the motor deficit remained similar to the initial presentation. The other patients showed a progression to the other limbs, suggesting a more diffuse process. Fifty-four percent of the patients treated with intravenous immunoglobulin showed an improvement, compared with 33% of the patients treated with oral steroids. Overall, 73% of patients had a positive response to immune-mediated therapy. LSS may be distinguished from MMN by the presence of sensory involvement, the absence of serum anti-GM1 antibodies and, in some cases, a positive response to steroids. In some of the patients in our study, LSS evolved into a more diffuse neuropathy sharing similarities with CIDP. Others had a clinical course characterized by a striking multifocal neuropathy, which suggests underlying mechanisms different from CIDP. Overall, whatever the clinical course, LSS responded to immune-mediated treatment in a manner similar to CIDP.

170 citations

Journal ArticleDOI
TL;DR: The aim of this retrospective study was to investigate patients with DADS neuropathy without anti‐MAG antibodies, and study their response to immunotherapy.
Abstract: Background and purpose: Some patients within the spectrum of chronic inflammatory demyelinating polyradiculoneuropathies (CIDP) have distal acquired demyelinating symmetric (DADS) neuropathy, usually associated with anti-myelin-associated-glycoprotein (MAG) IgM monoclonal gammopathy. The aim of this retrospective study was to investigate patients with DADS neuropathy without anti-MAG antibodies, and study their response to immunotherapy. Methods: Patients were selected on the basis of (i) ‘Definite CIDP’ according to the EFNS/PNS Guideline criteria, (ii) The presence of disproportionately prolonged motor latencies resulting in a terminal latency index (TLI) ≤0.25 in at least two motor nerves and (iii) The absence of anti-MAG antibodies on ELISA. Response to immunotherapy was defined as persistent improvement by at least one point on the INCAT disability score. Results: Data from 146 CIDP patients were analysed, and 10 patients were included. Six had clinically pure sensory neuropathy, and four had sensorimotor neuropathy. Ataxia was present in nine patients, generalized areflexia in seven and postural tremor in two. Five of the 10 patients had abnormal sensory potentials only in the upper limbs. An associated condition was found in nine patients: two chronic lymphocytic leukaemias, four IgG monoclonal gammopathies (one associated with non-Hodgkin’s lymphoma) and two IgM monoclonal gammopathies of unknown significance. Patients were mostly improved with intravenous immunoglobulin (IVIg), corticosteroids, plasma exchanges, or a combination thereof. Conclusion: DADS neuropathy without anti-MAG antibodies is more likely to be considered a variant of CIDP. In addition, such patients should be systematically investigated for an associated haematological or immunological condition.

78 citations

Journal ArticleDOI
TL;DR: A diagnostic strategy combining an EMG to distinguish between a demyelinating and an axonal pattern and measurement of anti‐MAG and anti‐ganglioside antibodies is proposed to help clinicians to identify the mechanism of neuropathy in order to adapt the therapeutic strategy.
Abstract: Neuropathy in Waldenstrom's macroglobulinemia (WM) is very heterogeneous. We retrospectively studied 40 patients with WM and neuropathy to analyze the different presentations and mechanisms encountered and to propose a diagnostic strategy. Twenty-five patients (62.5%) had axonal neuropathy, related to the following mechanisms: amyloid neuropathy (n = 5), cryoglobulinemic neuropathy (n = 5), neuropathy associated with tumoral infiltration (n = 2), vasculitic neuropathy (n = 2), a clinical motor neuropathy possibly of dysimmune origin (n = 6), or an unclassified mechanism (n = 5). A demyelinating pattern was observed in 15 patients, 10 having anti-myelin-associated glycoprotein (anti-MAG) antibodies and 5 having neuropathy related to chronic inflammatory demyelinating polyradiculoneuropathy. On the basis of these results, we propose a diagnostic strategy combining: (1) an EMG to distinguish between a demyelinating and an axonal pattern; (2) measurement of anti-MAG and anti-ganglioside antibodies; (3) screening for "red flag" features to orientate further investigations. This strategy may help clinicians to identify the mechanism of neuropathy in order to adapt the therapeutic strategy.

41 citations

Journal ArticleDOI
TL;DR: The prevalence of neuropathy in patients with immunoglobulin M (IgM) monoclonal gammopathies ranges from 5% to 31% and is usually a chronic demyelinating disorder that typically involves myelin-associated glycoprotein reaction.
Abstract: The prevalence of neuropathy in patients with immunoglobulin M (IgM) monoclonal gammopathies ranges from 5% to 31%.[1][1] The most frequent neuropathy is associated with monoclonal IgM reacting with myelin-associated glycoprotein (MAG) and is usually a chronic demyelinating disorder that typically

37 citations


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TL;DR: The in situ immune response profile and mechanisms of neuronal cell damage in fatal Zika microcephaly cases were investigated and changes found were mainly calcification, necrosis, neuronophagy, gliosis, microglial nodules, and inflammatory infiltration of mononuclear cells.
Abstract: Zika virus (ZIKV) has recently caused a pandemic disease, and many cases of ZIKV infection in pregnant women resulted in abortion, stillbirth, deaths and congenital defects including microcephaly, which now has been proposed as ZIKV congenital syndrome. This study aimed to investigate the in situ immune response profile and mechanisms of neuronal cell damage in fatal Zika microcephaly cases. Brain tissue samples were collected from 15 cases, including 10 microcephalic ZIKV-positive neonates with fatal outcome and five neonatal control flavivirus-negative neonates that died due to other causes, but with preserved central nervous system (CNS) architecture. In microcephaly cases, the histopathological features of the tissue samples were characterized in three CNS areas (meninges, perivascular space, and parenchyma). The changes found were mainly calcification, necrosis, neuronophagy, gliosis, microglial nodules, and inflammatory infiltration of mononuclear cells. The in situ immune response against ZIKV in the CNS of newborns is complex. Despite the predominant expression of Th2 cytokines, other cytokines such as Th1, Th17, Treg, Th9, and Th22 are involved to a lesser extent, but are still likely to participate in the immunopathogenic mechanisms of neural disease in fatal cases of microcephaly caused by ZIKV.

3,514 citations

Journal ArticleDOI
TL;DR: This is the first study providing evidence for Zika virus infection causing Guillain-Barré syndrome, and because Zika virus is spreading rapidly across the Americas, at risk countries need to prepare for adequate intensive care beds capacity to manage patients with Guillay-B Barré syndrome.

1,925 citations

Journal Article
TL;DR: High-dose of intravenous immunoglobulin (0.4 g/kg daily for 5 days) and PE are equally effective in intermediate and severe forms and the choice between the two treatments depends on their respective contra-indications and local availability.
Abstract: L'incidence annuelle du syndrome de Guillain-Barre est de 1,5/100000 habitants La mortalite actuelle est estimee a environ 5 % d'apres des essais therapeutiques recents, bien conduits Dix pour cent des malades gardent des sequelles motrices tres invalidantes un an apres le debut des premiers signes neurologiques La prise en charge de ces malades necessite des equipes entrainees, multidisciplinaires, pouvant pratiquer l'ensemble des therapeutiques specifiques La corticotherapie per os'ou par voie intraveineuse est inefficace Les echanges plasmatiques sont le premier traitement dont l'efficacite a ete demontree par rapport a un groupe controle Les indications sont maintenant mieux connues Les formes benignes (marche possible) beneficient de 2 echanges plasmatiques; 2 echanges supplementaires sont realises en cas d'aggravation Dans les formes intermediaires (marche impossible) et les formes severes (recours a la ventilation mecanique), 4 echanges plasmatiques sont conseilles Il n'est pas utile d'augmenter leur nombre dans les formes severes ou en cas d'absence d'amelioration De fortes doses d'immunoglobulines donnees par voie intraveineuse (lq IV) [0,4 g/kg/j pendant 5 jours] sont aussi efficaces que les echanges plasmatiques dans les formes intermediaires et severes Dans ces formes, le choix entre Ig IV et echanges plasmatiques depend des contre-indications respectives de ces traitements et de leur faisabilite Les travaux en cours ont comme objectif de mieux preciser les indications respectives des echanges plasmatiques et des lq IV dans des formes de gravite differente, leur morbidite comparee, la dose optimale des lq IV

1,842 citations

Journal ArticleDOI
11 May 2016-Nature
TL;DR: It is demonstrated that the ZIKVBR infects fetuses, causing intra-uterine growth restriction (IUGR), and crosses the placenta and causes microcephaly by targeting cortical progenitor cells, inducing cell death by apoptosis and autophagy, impairing neurodevelopment.
Abstract: Zika virus (ZIKV) is an arbovirus belonging to the genus Flavivirus (family Flaviviridae) and was first described in 1947 in Uganda following blood analyses of sentinel Rhesus monkeys. Until the twentieth century, the African and Asian lineages of the virus did not cause meaningful infections in humans. However, in 2007, vectored by Aedes aegypti mosquitoes, ZIKV caused the first noteworthy epidemic on the Yap Island in Micronesia. Patients experienced fever, skin rash, arthralgia and conjunctivitis. From 2013 to 2015, the Asian lineage of the virus caused further massive outbreaks in New Caledonia and French Polynesia. In 2013, ZIKV reached Brazil, later spreading to other countries in South and Central America. In Brazil, the virus has been linked to congenital malformations, including microcephaly and other severe neurological diseases, such as Guillain-Barre syndrome. Despite clinical evidence, direct experimental proof showing that the Brazilian ZIKV (ZIKV(BR)) strain causes birth defects remains absent. Here we demonstrate that ZIKV(BR) infects fetuses, causing intrauterine growth restriction, including signs of microcephaly, in mice. Moreover, the virus infects human cortical progenitor cells, leading to an increase in cell death. We also report that the infection of human brain organoids results in a reduction of proliferative zones and disrupted cortical layers. These results indicate that ZIKV(BR) crosses the placenta and causes microcephaly by targeting cortical progenitor cells, inducing cell death by apoptosis and autophagy, and impairing neurodevelopment. Our data reinforce the growing body of evidence linking the ZIKV(BR) outbreak to the alarming number of cases of congenital brain malformations. Our model can be used to determine the efficiency of therapeutic approaches to counteracting the harmful impact of ZIKV(BR) in human neurodevelopment.

1,095 citations

Journal ArticleDOI
TL;DR: The data for GBS suggests that the immunologic mechanism can involve molecular mimicry, at least in some GBS variants, and it is likely that multiple mechanisms render the axon vulnerable.

925 citations