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Concept: Chronic inflammatory demyelinating polyneuropathy

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Background Zika virus (ZIKV) infection has been linked to the Guillain-Barré syndrome. From November 2015 through March 2016, clusters of cases of the Guillain-Barré syndrome were observed during the outbreak of ZIKV infection in Colombia. We characterized the clinical features of cases of Guillain-Barré syndrome in the context of this ZIKV infection outbreak and investigated their relationship with ZIKV infection. Methods A total of 68 patients with the Guillain-Barré syndrome at six Colombian hospitals were evaluated clinically, and virologic studies were completed for 42 of the patients. We performed reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assays for ZIKV in blood, cerebrospinal fluid, and urine, as well as antiflavivirus antibody assays. Results A total of 66 patients (97%) had symptoms compatible with ZIKV infection before the onset of the Guillain-Barré syndrome. The median period between the onset of symptoms of ZIKV infection and symptoms of the Guillain-Barré syndrome was 7 days (interquartile range, 3 to 10). Among the 68 patients with the Guillain-Barré syndrome, 50% were found to have bilateral facial paralysis on examination. Among 46 patients in whom nerve-conduction studies and electromyography were performed, the results in 36 patients (78%) were consistent with the acute inflammatory demyelinating polyneuropathy subtype of the Guillain-Barré syndrome. Among the 42 patients who had samples tested for ZIKV by RT-PCR, the results were positive in 17 patients (40%). Most of the positive RT-PCR results were in urine samples (in 16 of the 17 patients with positive RT-PCR results), although 3 samples of cerebrospinal fluid were also positive. In 18 of 42 patients (43%) with the Guillain-Barré syndrome who underwent laboratory testing, the presence of ZIKV infection was supported by clinical and immunologic findings. In 20 of these 42 patients (48%), the Guillain-Barré syndrome had a parainfectious onset. All patients tested were negative for dengue virus infection as assessed by RT-PCR. Conclusions The evidence of ZIKV infection documented by RT-PCR among patients with the Guillain-Barré syndrome during the outbreak of ZIKV infection in Colombia lends support to the role of the infection in the development of the Guillain-Barré syndrome. (Funded by the Bart McLean Fund for Neuroimmunology Research and others.).

Concepts: Dengue fever, Cerebrospinal fluid, The Onset, Fever, Immune system, 2015, 2016, Chronic inflammatory demyelinating polyneuropathy

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Abstract There has been only one reported case of neuromuscular scoliosis following chronic inflammatory demyelinating polyneuropathy (CIDP). However, no cases of scoliosis that were treated with surgery secondary to CIDP have been previously described. A 16-year-old boy with CIDP was consultant due to the progression of scoliosis with the coronal curve of 86° from T8 to T12. Posterior correction and fusion with segmental pedicle screws were performed under intraoperative spinal cord monitoring with transcranial electric motor-evoked potentials. Although the latency period was prolonged and amplitude was low, the potential remained stable. Coronal curve was corrected from 86° to 34° without neurological complications. We here describe scoliosis associated with CIDP, which was successfully treated with surgery under intraoperative spinal cord monitoring.

Concepts: Report, Case, Potential, Surgery, Neurological disorders, Myelin, Medicine, Chronic inflammatory demyelinating polyneuropathy

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Glossopharyngeal and/or vagus nerve involvement is infrequent in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). We herein report the case of a 69-year-old Japanese woman who presented with muscle weakness and numbness of the extremities with dysphagia. The serum anti-ganglioside GM1 immunoglobulin IgM antibody levels were elevated, and treatment with intravenous immunoglobulin (IVIg) resulted in a dramatic improvement; the weakness, numbness and dysphagia all resolved. However, relapse comprising dysphagia alone occurred on hospital day 26, and treatment with IVIg again proved extremely effective. IVIg therapy can be effective against cranial nerve involvement in cases of CIDP.

Concepts: Accessory nerve, Nucleus ambiguus, Myelin, Antibody, Chronic inflammatory demyelinating polyneuropathy, Immune system, Intravenous immunoglobulin, Cranial nerves

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Auto-antibodies against the paranodal proteins neurofascin-155 and contactin-1 have recently been described in patients with chronic inflammatory demyelinating polyradiculoneuropathy and are associated with a distinct clinical phenotype and response to treatment. Contactin-associated protein 1 (Caspr, encoded by CNTNAP1) is a paranodal protein that is attached to neurofascin-155 and contactin-1 (CNTN1) but has not yet been identified as a sole antigen in patients with inflammatory neuropathies. In the present study, we screened a cohort of 35 patients with chronic inflammatory demyelinating polyradiculoneuropathy (age range 20-80, 10 female, 25 male) and 22 patients with Guillain-Barré syndrome (age range 17-86, eight female, 14 male) for autoantibodies against paranodal antigens. We identified two patients, one with chronic inflammatory demyelinating polyradiculoneuropathy and one with Guillain-Barré syndrome, with autoantibodies against Caspr by binding assays using Caspr transfected human embryonic kidney cells and murine teased fibres. IgG3 was the predominant autoantibody subclass in the patient with Guillain-Barré syndrome, IgG4 was predominant in the patient with chronic inflammatory demyelinating polyradiculoneuropathy. Accordingly, complement deposition after binding to HEK293 cells was detectable in the patient with IgG3 autoantibodies only, not in the patient with IgG4. Severe disruption of the paranodal and nodal architecture was detectable in teased fibres of the sural nerve biopsy and in dermal myelinated fibres, supporting the notion of the paranodes being the site of pathology. Deposition of IgG at the paranodes was detected in teased fibre preparations of the sural nerve, further supporting the pathogenicity of anti-Caspr autoantibodies. Pain was one of the predominant findings in both patients, possibly reflected by binding of patients' IgG to TRPV1 immunoreactive dorsal root ganglia neurons. Our results demonstrate that the paranodal protein Caspr constitutes a new antigen that leads to autoantibody generation as part of the novel entity of neuropathies associated with autoantibodies against paranodal proteins.

Concepts: Chronic inflammatory demyelinating polyneuropathy, Antigen, Pain, Protein, HEK cell, Myelin, Immune system, Nervous system

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OBJECTIVE: To investigate changes in the T-cell repertoire in patients with chronic inflammatory demyelinating polyneuropathy (CIDP) without and with treatment of IV immunoglobulins (IVIg). METHODS: The T-cell receptor (TCR) repertoire of CD4+ and CD8+ T cells in the peripheral blood was analyzed using CDR3 spectratyping. Patients with CIDP were included without (n = 14) and with IVIg treatment (n = 11) cross-sectionally and longitudinally (n = 2). RESULTS: While the TCR length distribution of patients with CIDP was only moderately altered for most of the Vβ elements of CD4+ T cells, the CD8+ population displayed extensive oligoclonal expansions in all analyzed 24 Vβ elements. A public expansion of a distinct TCR length in one Vβ element within a majority of affected patients was not detectable. Treatment with IVIg reduced the oligoclonal expansions within both the CD4+ and CD8+ population. CONCLUSIONS: Our data demonstrate that cytotoxic CD8+ T cells exhibit a much broader activation than CD4+ T cells, indicating a potentially crucial role of CD8+ T cells in the immunopathogenesis of CIDP. The profound oligoclonal response in T-cell activation suggests that multiple peptides may induce and propagate this autoimmune-driven disease. The observed reduction of highly activated T cells may contribute to the therapeutic effects of IVIg.

Concepts: Immune system, Myelin, Intravenous immunoglobulin, Protein, Natural killer cell, T cell, T cell receptor, Chronic inflammatory demyelinating polyneuropathy

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Fas is a transmembrane receptor involved in the death program of several cell lines, including T lymphocytes. Deleterious mutations hitting genes involved in the Fas pathway cause the autoimmune lymphoprolipherative syndrome (ALPS). Moreover, defective Fas function is involved in the development of common autoimmune diseases, including autoimmune syndromes hitting the nervous system, such as multiple sclerosis (MS) and chronic inflammatory demyelinating polyneuropathy (CIDP). In this review, we first explore some peculiar aspects of Fas mediated apoptosis in the central versus peripheral nervous system (CNS, PNS); thereafter, we analyze what is currently known on the role of T cell apoptosis in both MS and CIDP, which, in this regard, may be seen as two faces of the same coin. In fact, we show that, in both diseases, defective Fas mediated apoptosis plays a crucial role favoring disease development and its chronic evolution.

Concepts: Multiple sclerosis, Peripheral nervous system, Autoimmune diseases, Central nervous system, Chronic inflammatory demyelinating polyneuropathy, Nervous system, Myelin, Immune system

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The clinical presentation, disease course, response to treatment, and long-term outcome of thirty childhood chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) patients are presented representing the largest cohort reported to date. Most children (60%) presented with chronic (>8-weeks) symptom-onset while a smaller proportion showed sub-acute (4-8 weeks) or acute (“GBS-like”; <4 weeks) onset of disease. No gender predilection was observed. The majority of patients had a relapsing (70%) versus a monophasic (30%) temporal profile. Most received initial IVIG monotherapy; 80% showing a good response. Long-term follow-up (mean=3.8 years) was available for 23 patients; 45% were off all immunomodulatory medications, demonstrating no detectable (55%) or minimal (43%) clinical deficits. Our data were compared with 11 previously published childhood CIDP series providing a comprehensive review of 143 childhood CIDP cases. The combined initial or first-line treatment response across all studies was favourable for IVIG (79% patients) and corticosteroids (84% patients). Response to first-line plasma exchange was poor (only 14% patients improved) although it may offer some transient or partial benefit as an adjuvant or temporary therapy for selected patients. The combined long-term outcome of our cohort and the literature reveals a favourable prognosis for most patients. The combined modified Rankin scale decreased from 3.7 (at presentation) to 0.7 (at last follow-up). This review provides important data pertaining to clinical course, treatment response and long-term outcome of this relatively uncommon paediatric autoimmune disease.

Concepts: Neurological disorders, Progressive inflammatory neuropathy, Modified Rankin Scale, Medicine, Myelin, Plasmapheresis, Autoimmune diseases, Chronic inflammatory demyelinating polyneuropathy

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Abstract Ultrasonographic nerve enlargement has primarily been reported in patients with inflammatory neuropathies such as chronic inflammatory demyelinating polyneuropathy (CIDP), multifocal motor neuropathy, Guillain-Barre syndrome, vasculitic neuropathy and leprosy. Nerve ultrasonography is a promising diagnostic supportive tool for inflammatory neuropathies. The ultrasonographic findings that are currently useful are 1) nerve enlargement primarily suggests the existence of inflammatory or demyelinating neuropathies and 2) for patients with CIDP or demyelinating Charcot-Marie-Tooth disease, the pattern of nerve enlargement is noted, and this pattern is useful for discriminating between these diseases. More precise evidence of ultrasonographic findings for inflammatory neuropathies should be established in the future.

Concepts: Dapsone, Vincristine, Nervous system, Myelin, Guillain–Barré syndrome, Chronic inflammatory demyelinating polyneuropathy, Peripheral neuropathy, Neurological disorders

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Lower motor neuron (LMN) syndromes typically present with muscle wasting and weakness and may arise from pathology affecting the distal motor nerve up to the level of the anterior horn cell. A variety of hereditary causes are recognised, including spinal muscular atrophy, distal hereditary motor neuropathy and LMN variants of familial motor neuron disease. Recent genetic advances have resulted in the identification of a variety of disease-causing mutations. Immune-mediated disorders, including multifocal motor neuropathy and variants of chronic inflammatory demyelinating polyneuropathy, account for a proportion of LMN presentations and are important to recognise, as effective treatments are available. The present review will outline the spectrum of LMN syndromes that may develop in adulthood and provide a framework for the clinician assessing a patient presenting with predominantly LMN features.

Concepts: Spinal cord, Chronic inflammatory demyelinating polyneuropathy, Motor neuron, Muscle atrophy, Nervous system, Motor neurone disease, Atrophy, Muscle