Guillain-Barré syndrome: a century of progress

Refractory Crohn's disease complicated with Guillain-Barré syndrome: A case report

BACKGROUND

Inflammatory bowel disease (IBD) comprises a group of chronic inflammatory gastrointestinal disorders, including Crohn's disease (CD) and ulcerative colitis, with uncertain etiologies. The natural course of IBD can be accompanied by extraintestinal manifestations involving the skin, mucous membranes, musculoskeletal structures, eyes, cardiovascular system and nervous system. Guillain-Barré syndrome (GBS) is a type of peripheral neuropathy. However, the etiology and pathogenesis of IBD combined with GBS are unclear, and only a few clinical cases have been reported. Here, we report a case of refractory CD complicated by GBS and review the previous literature to improve the understanding of these diseases.

CASE SUMMARY

A 34-year-old man had a 9-year history of refractory CD. He became unresponsive to multiple drugs and experienced recurrent intestinal fistulas. After several abdominal surgeries and treatment with ustekinumab, he achieved clinical remission. Unfortunately, he developed GBS during maintenance treatment with ustekinumab. According to previous reports, in some patients with IBD combined with GBS, GBS may be a comorbidity, an extraintestinal manifestation of IBD, or an adverse reaction to IBD therapeutic drugs. After a comprehensive evaluation, we suspected that GBS might have been a comorbidity in this patient. To avoid fatal disease relapse after medication discontinuation, we concluded that ustekinumab should not be withdrawn. On the basis of a joint decision between doctors and the patient, we decided to continue maintenance treatment with ustekinumab along with intravenous immunoglobulin, dexamethasone and traditional Chinese medicine acupuncture, which resulted in a steady improvement in his GBS symptoms and sustained remission of CD.

CONCLUSION

When IBD is complicated by a neurological disease, it is first necessary to analyze the patient's condition and then choose the corresponding treatment strategy. If the neurological disease is a specific comorbidity, treatment of both IBD and the comorbid disease should be considered. For IBD patients with extraintestinal manifestations involving the nervous system, neurological manifestations tend to resolve when the active IBD is controlled. When an adverse drug reaction is suspected, the medication should be discontinued, and symptomatic treatment should be administered.

Sequential administration of efgartigimod shortened the course of Guillain-Barré syndrome: a case series

Guillain-Barré syndrome (GBS) is a serious neurological condition with limited treatment options. A recent report demonstrated successful treatment with efgartigimod alone in two patients with GBS, although it did not significantly shorten the disease duration. This case series investigates the effects of sequential efgartigimod administration in patients with different GBS phenotypes and varying levels of disease severity. All three patients tested positive for immunoglobulin G (IgG) antibodies against serum gangliosides. In Case 1, the patient was treated with 0.4 g/kg of intravenous immunoglobulin (IVIg) for 5 days, showing minimal recovery. After receiving 3 weekly doses of efgartigimod (10 mg/kg), the patient achieved independent ambulation 19 days post-onset, with a reduction in serum ganglioside antibody titers and total IgG levels. Case 2 involved a middle-aged man with Miller Fisher syndrome (MFS)-GBS overlap, who experienced worsened autonomic dysfunction following IVIg treatment. After three doses of efgartigimod, the patient showed symptom improvement within 1 month, alongside a reduction in IgG antibody levels. In Case 3, a 27-year-old male with MFS-GBS overlap, initially unresponsive to IVIg, showed significant improvement in ophthalmoplegia following two doses of efgartigimod, with his serum ganglioside antibodies eventually becoming undetectable. Our findings suggest that sequential efgartigimod treatment may effectively reduce serum anti-ganglioside antibody titers and potentially shorten the disease course in severe GBS and MFS-GBS overlap syndrome. Additionally, it may offer clinical benefits for patients with GBS who have a poor or no response to IVIg, particularly in treating ophthalmoplegia.

Clinical characteristics of Guillain-Barré syndrome in Shenzhen: a retrospective study

BACKGROUND

Guillain-Barré syndrome (GBS) is a group of immune-mediated peripheral neuropathies that causes acute flaccid paralysis. The global incidence of GBS was 0.6-4/100 000, and the incidence in China was 0.698/100 000. Although the diagnosis and treatment of GBS has made rapid progress, approximately 20% of patients with GBS are still unable to walk alone within 6 months after the onset of GBS, and 40% of patients have sequelae, such as weakened strength, limb pain, and numbness, seriously affecting their life and work. We aimed to retrospectively analyze the clinical characteristics of patients with GBS in Shenzhen, China and analyze the factors affecting disease severity to provide a reference for the precise treatment of GBS.

METHODS

Clinical data of inpatients diagnosed with GBS in several hospitals in Shenzhen from April 2010 to October 2021 were obtained from an electronic medical record system (HIS system). The clinical characteristics of patients with GBS and the factors affecting disease severity were analyzed.

RESULTS

A total of 146 patients were identified for this study, and 13 were lost during follow-up. During the follow-up period, three patients had acute-onset chronic inflammatory demyelinating polyneuropathy (A-CIDP). One hundred and thirty patients with complete data, comprising 90 males (69.23%) and 40 females (30.77%) with a median age of 39.50 ± 23.75 years, were included in the statistical analyses. Acute inflammatory demyelinating polyneuropathy (AIDP) was the most common electrophysiological variant (106 cases [81.54%]). Miller-Fisher syndrome (MFS), acute motor axonal neuropathy (AMAN), and acute motor-sensory axonal neuropathy (AMSAN) were noted in 21 (16.15%), 2 (1.54%), and 1 (0.77%) patients, respectively. The clinical course of the disease was mainly mild in 95 cases (73.08%), while 35 patients (26.92%) experienced severe disease. Logistic multivariate regression analysis showed that age ≥ 60 years old and having pneumonia may be associated with the severity of the disease.

CONCLUSIONS

AIDP is the most common electrophysiological variant of GBS in Shenzhen. Most cases of GBS in our setting are mild, and the long-term prognosis is favorable. Old age (≥ 60 years) and having pneumonia are independent risk factors for severe GBS.

Kaempferol attenuates experimental autoimmune neuritis through TNFR1/JNK/p38 signaling pathway inhibition

Kaempferol (Kae) is a flavonoid that has antioxidant, anti-inflammatory and neuroprotective effects. In recent years, there have been increasing reports on viral infection-induced Guillain-Barré syndrome (GBS) with high rates of disability and fatality. Therefore, in order to search for effective peripheral nerve injury repair drugs, we used rats with experimental autoimmune neuritis (EAN) as the typical animal model for GBS, and implemented Kae treatment intervention on EAN rats. Real-time quantitative polymerase chain reaction (qPCR), western blotting (WB) and immunofluorescence (IF) were utilized to detect the changes of inflammatory factors and signaling pathway proteins in peripheral nerve of rats. The impact of Kae on peripheral nerve damage in EAN rats was evaluated in multiple dimensions by clinical symptom score and neuroelectrophysiology examination, and the protective impact and mechanism of Kae on peripheral nerve injury were revealed. Our results showed that Kae increased the expression of sciatic myelin basic protein (MBP), decreased the expression of peripheral nerve macrophage infiltration and inflammatory cytokines, including TNF-α, IL-1β and IL-6, and down-regulated the expression levels of TNFR1. Additionally, it suppressed the activation of the JNK and p38 pathways. It can alleviate sciatic nerve symptoms and pathological injury in EAN rats. Therefore, we believe that Kae can be used as an adjunct drug in the treatment of GBS.

Predictors of the Short-Term Outcomes of Guillain-Barré Syndrome: Exploring Electrodiagnostic and Clinical Features

BACKGROUND AND OBJECTIVES

Guillain-Barré syndrome (GBS), an acute inflammatory disorder of the peripheral nervous system, is characterized by muscle weakness and paralysis. Prompt identification of patients at a high risk of poor outcomes is crucial for timely intervention. In this study, we combined clinical data with nerve conduction study and electromyography data to identify the predictors of GBS outcomes.

METHODS

We retrospectively analyzed the data of patients with GBS who had received treatment at Chang Gung Memorial Hospital, Taiwan, between 1998 and 2022. Comprehensive clinical and electrophysiological data were collected. Statistical analyses were performed to identify the predictors of poor outcomes. The patients were stratified into two groups by their scores on the GBS Disability Scale: good (score ≤ 2) and poor (score > 2) outcome groups.

RESULTS

The study finally included 24 GBS patients (mean age: 53.0 ± 20.9 years; female-to-male ratio: 2.3; good outcome group: 13; poor outcome group: 11). Compared with the good outcome group, the poor outcome group was old (43.0 ± 20.4 vs. 64.0 ± 15.7, p = 0.011), had a short time-to-treatment period (12.9 ± 7.8 vs. 6.5 ± 5.4 days, p = 0.033), exhibited more prevalent mechanical ventilation use (0 vs. 36.4%, p = 0.017), and had a prolonged hospitalization duration (14.7 ± 10.2 vs. 53.1 ± 20.0 days, p < 0.001). Poor outcomes were associated with low compound muscle action potential (CMAP), slow motor nerve conduction velocity (MNCV), abnormal F-wave latency, and more conduction block and temporal dispersion. In the subgroup of acute inflammatory demyelinating polyradiculoneuropathy (AIDP), there were 19 patients, out of which 10 had good outcomes, while nine had poor outcomes. The clinical features that differentiate between good and poor outcomes in the AIDP subgroup were similar to those observed in all GBS patients. Notably, the motor conduction features, including distal and proximal CMAP and MNCV of the median and tibial nerves (all p < 0.05), were particularly important electrodiagnostic features of outcome discrimination in the AIDP subgroup.

DISCUSSION

Combining clinical data with nerve conduction study and electromyography data can assist in predicting outcomes of both GBS patients and the AIDP subgroup. Poor outcomes are associated with older age, a more abrupt onset pattern, low CMAP, and slow nerve conduction, and abnormal tibial F responses can predict poor outcomes. Early identification of high-risk patients facilitates tailored interventions. This highlights the importance of combining clinical and electrophysiological data in GBS management.

Resolution of acute motor axonal neuropathy in a patient after treatment with efgartigimod: A case report

BACKGROUND

Guillain-Barré syndrome (GBS) is an acute autoimmune neuropathy characterized by progressive muscle weakness, often caused by immunoglobulin G (IgG) autoantibodies. There are several subtypes of GBS, of which acute motor axonal neuropathy (AMAN) is one of the most severe subtypes associated with axonal damage. It is well known that the current clinical standard of treatment is intravenous immunoglobulin (IVIg) and plasma exchange (PLEX), but some patients often show limited response or experience persistent disability. Efgartigimod, an Fc fragment of human IgG antibody, provides a way to target and reduce pathogenic IgG antibodies as a natural ligand Fc receptor (FcRn). The purpose of this study was to observe the therapeutic effect of efgartigimod on axonal GBS, which is expected to be a potential therapeutic method for GBS and AMAN.

METHODS

We present a case of a 58-year-old man diagnosed with AMAN, presenting with ascending symmetrical limb weakness, flaccid paralysis, and multiple cranial nerve palsies. Electromyography confirmed the axonal subtype of GBS. Despite receiving IVIg and PLEX, the patient showed suboptimal recovery. Subsequently, he was treated with efgartigimod at a dose of 10 mg/kg weekly for 4 weeks, demonstrating significant improvement in both clinical symptoms and electromyographic findings, with good tolerability.

RESULT

This case highlights the potential efficacy and safety of a 4-dose efgart-igimod regimen in AMAN, particularly for patients with inadequate response to conventional therapies. By targeting FcRn and promoting IgG degradation, efgartigimod offers a novel mechanism to modulate the aberrant immune response underlying AMAN.

CONCLUSION

Efgartigimod at a dose of 10 mg/kg weekly for 4 weeks demonstrated promising results in this case of AMAN. While further research is warranted, our findings suggest that efgartigimod may represent a valuable addition to the therapeutic armamentarium for AMAN and potentially other autoimmune neurological conditions. Well-designed clinical trials are crucial to confirm these findings and establish optimal treatment protocols for efgartigimod in AMAN.

Genomic variability in Zika virus in GBS cases in Colombia

Major clusters of Guillain-Barré Syndrome (GBS) emerged during the Zika virus (ZIKV) outbreaks in the South Pacific and the Americas from 2014 to 2016. The factors contributing to GBS susceptibility in ZIKV infection remain unclear, although considerations of viral variation, patient susceptibility, environmental influences, and other potential factors have been hypothesized. Studying the role of viral genetic factors has been challenging due to the low viral load and rapid viral clearance from the blood after the onset of Zika symptoms. The prolonged excretion of ZIKV in urine by the time of GBS onset, when the virus is no longer present in the blood, provides an opportunity to unravel whether specific ZIKV mutations are related to the development of GBS in certain individuals. This study aimed to investigate the association between specific ZIKV genotypes and the development of GBS, taking advantage of a unique collection of ZIKV-positive urine samples obtained from GBS cases and controls during the 2016 ZIKV outbreak in Colombia. Utilizing Oxford-Nanopore technology, we conducted complete genome sequencing of ZIKV in biological samples from 15 patients with GBS associated with ZIKV and 17 with ZIKV infection without neurological complications. ZIKV genotypes in Colombia exhibited distribution across three clades (average bootstrap of 90.9±14.9%), with two clades dominating the landscape. A comparative analysis of ZIKV genomes from GBS and non-neurological complications, alongside 1368 previously reported genomes, revealed no significant distinctions between the two groups. Both genotypes were similarly distributed among observed clades in Colombia. Furthermore, no variations were identified in the amino acid composition of the viral genome between the two groups. Our findings suggest that GBS in ZIKV infection is perhaps associated with patient susceptibility and/or other para- or post-infectious immune-mediated mechanisms rather than with specific ZIKV genome variations.

Mycoplasma pneumoniae-Triggered Guillain-Barré Syndrome in Children: Two Case Reports of Different ICU Presentations

Guillain-Barré syndrome (GBS) is an acute immune-mediated polyneuropathy with diverse clinical presentations. Mycoplasma pneumoniae has been increasingly recognized as a potential trigger, particularly in pediatric cases. This case report presents two atypical cases of M. pneumoniae-associated GBS in children in the pediatric intensive care unit setting. The first case involves a 10-year-old boy with pharyngeal-cervical-brachial variant of GBS, presented with descending paralysis and required prolonged mechanical ventilation and tracheostomy. The second case presents a two-year-old boy with ascending GBS complicated by underlying sickle cell anemia. Both cases illustrate that pediatric GBS requires prompt diagnosis and aggressive treatment. In these instances, GBS was linked to M. pneumoniae.

Long-term outcomes of patients affected by Guillain-Barré syndrome in Colombia after the Zika virus epidemic

BACKGROUND

Guillain-Barré Syndrome (GBS) can lead to significant functional impairments, yet little is understood about the recovery phase and long-term consequences for patients in low- and medium-income countries.

OBJECTIVE

To evaluate the functional status and identify factors influencing outcomes among patients with GBS in Colombia.

METHODS

Telephone interviews were conducted with GBS patients enrolled in the Neuroviruses Emerging in the Americas Study between 2016 and 2020. The investigation encompassed access to health services and functional status assessments, utilizing the modified Rankin Scale (mRS), GBS Disability Score (GDS), Barthel Index (BI), and International Classification of Functioning (ICF). Univariate analysis, principal component analysis, linear discriminant analysis, and linear regression were employed to explore factors influencing functional status.

RESULTS

Forty-five patients (mean age = 50[±22] years) with a median time from diagnosis of 28 months (IQR = 9-34) were included. Notably, 22% and 16% of patients did not receive rehabilitation services during the acute episode and post-discharge, respectively. Most patients demonstrated independence in basic daily activities (median BI = 100, IQR = 77.5-100), improvement in disability as the median mRS at follow-up was lower than at onset (1 [IQR = 0-3] vs. 4.5 [IQR = 4-5], p < 0.001), and most were able to walk without assistance (median GDS = 2, IQR = 0-2). A shorter period from disease onset to interview was associated with worse mRS (p = 0.015) and ICF (p = 0.019). Negative outcomes on GDS and ICF were linked to low socioeconomic status, ICF to the severity of weakness at onset, and BI to an older age.

CONCLUSIONS

This study underscores that the functional recovery of GBS patients in Colombia is influenced not only by the natural course of the disease but also by socioeconomic factors, emphasizing the crucial role of social determinants of health.

High risk and low prevalence diseases: Guillain-Barré syndrome

INTRODUCTION

Guillain-Barré syndrome (GBS) is a rare but serious condition that carries with it a high rate of morbidity and mortality.

OBJECTIVE

This review highlights the pearls and pitfalls of GBS, including presentation, diagnosis, and management in the emergency department (ED) based on current evidence.

DISCUSSION

GBS is a rare immune-mediated neurologic disorder with peripheral nerve injury. It most commonly presents weeks after a bacterial or viral infection, though there are a variety of associated inciting events. The diagnosis is challenging and often subtle, as only 25-30% of patients are diagnosed on their initial healthcare visit. Clinicians should consider GBS in patients with progressive ascending weakness involving the lower extremities associated with hyporeflexia, but the cranial nerves, respiratory system, and autonomic system may be involved. While the ED diagnosis should be based on clinical assessment, further evaluation includes laboratory testing, cerebrospinal fluid (CSF) analysis, and potentially neuroimaging. Not all patients demonstrate albumino-cytological dissociation on CSF testing. Several criteria exist to assist with diagnosis, including the National Institute of Neurological Disorders and Stroke criteria and the Brighton criteria. Management focuses first on assessment of the patient's hemodynamic and respiratory status, which may require emergent intervention. Significant fluctuations in heart rate and blood pressure may occur, and respiratory muscle weakness may result in the need for airway protection. Neurology consultation is recommended, and definitive treatment includes PLEX or IVIG.

CONCLUSIONS

An understanding of GBS can assist emergency clinicians in diagnosing and managing this potentially deadly disease.

Current status of Guillain-Barré syndrome (GBS) in China: a 10-year comprehensive overview

Guillain-Barré syndrome (GBS) is an acute inflammatory polyradiculoneuropathy; a disease involving the peripheral nervous system which is the most common cause of acute flaccid paralysis worldwide. So far, it is still lack of a comprehensive overview and understanding of the national epidemiological, clinical characteristics, and the risk factors of GBS in China, as well as differences between China and other countries and regions in these respects. With the global outbreak of the coronavirus disease 2019 (COVID-19), an epidemiological or phenotypic association between severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection and GBS has attracted great attention. In this review, we outlined the current clinical data of GBS in China by retrieving literature, extracting and synthesizing the data of GBS in China from 2010 to 2021. Besides, we compared the characteristics of epidemiology, preceding events and clinical profiles of GBS between China and other countries and regions. Furthermore, in addition to conventional intravenous immunoglobulin (IVIG) and plasma exchange (PE) therapy, the potential therapeutic effects with novel medications in GBS, such as complement inhibitors, etc., have become the research focus in treatments. We found that epidemiological and clinical findings of GBS in China are approximately consistent with those in the International GBS Outcome Study (IGOS) cohort. We provided an overall picture of the present clinical status of GBS in China and summarized the global research progress of GBS, aiming to further understand the characteristics of GBS and improve the future work of GBS worldwide, especially in countries with the middle and low incomes.

Detection of resistance and virulence plasmids in Campylobacter coli and Campylobacter jejuni isolated from North Carolina food animal production, 2018-2019

Campylobacter remains the leading cause of bacterial foodborne illness in the U.S. and worldwide. Campylobacter plasmids may play a significant role in antimicrobial resistance (AMR) and virulence factor distribution, and potentially drive rapid adaptation. C. coli (n = 345) and C. jejuni (n = 199) isolates collected from live cattle, swine, turkey, and chickens, poultry carcasses at production, and retail meat in N.C. were analyzed to determine plasmid prevalence, extrachromosomal virulence and AMR genes, and the phylogeny of assembled plasmids. Putative plasmids ranging from <2 kb to 237kb were identified with virulence factors present in 66.1% (228/345) C. coli and 88.4% (176/199) C. jejuni plasmids (promoting adherence, invasion, exotoxin production, immune modulation, chemotaxis, mobility, and the type IV secretion system). AMR genes were identified in 21.2% (73/345) C. coli and 28.1% C. jejuni plasmids (conferring resistance to tetracyclines, aminoglycosides, beta-lactams, nucleosides, and lincosamides). Megaplasmids (>100 kb) were present in 25.7% (140/544) of the isolates and carried genes previously recognized to be involved with interspecies recombination. Our study highlights the extensive distribution and diversity of Campylobacter plasmids in food animal production and their role in the dissemination of biomedically important genes. Characterizing Campylobacter plasmids within the food animal production niche is important to understanding the epidemiology of potential emerging strains.

Construction and evaluation of a prognostic prediction model based on the mEGOS score for patients with Guillain-Barré syndrome

Background

Guillain-Barré syndrome (GBS) is an immune-mediated acute peripheral neuropathy in which up to 20% patients remain unable to walk independently after 6 months of onset. This study aimed to develop a clinical prognostic model based on the modified Erasmus GBS Outcome Score (mEGOS) for predicting the prognosis of GBS patients at 6 months of onset.

Methods

The clinical data of 201 GBS patients were retrospectively analyzed. According to the GBS disability score (GBS-DS) at 6 months of onset, patients were divided into a good prognosis group (GBS-DS <3 points) and a poor prognosis group (GBS-DS≥3 points). Univariate and multivariate analysis was used to screen out independent risk factors for poor prognosis, and a prediction model was accordingly constructed for GBS prognosis.

Results

The mEGOS score, serum albumin (ALB) and fasting plasma glucose (FPG) were independent risk factors for poor prognosis in patients with GBS, and the above risk factors were used to construct a prognostic model of mEGOS-I and a nomogram. The receiver operating characteristic (ROC) curve showed that the area under curve (AUC) of mEGOS-I at admission and at 7 days of admission to predict poor prognosis at 6 months of GBS onset was 0.891 and 0.916, respectively, with sensitivities of 82.7% and 82.6% and specificities of 86.5% and 86.6%, respectively. Decision curve analysis showed that the nomogram had a very high clinical benefit.

Conclusion

To our knowledge, this is the first report of the construction of a prognostic prediction model based on the mEGOS score, ALB, and FPG that can accurately and stably predict the prognosis of GBS patients at 6 months of onset.

Clinical Features and Differences of Miller Fisher Syndrome in Southern China: Retrospective Analysis of 72 Patients in 13 Provinces of Southern China

BACKGROUND AND PURPOSE

We aimed to determine the clinical features of Miller Fisher syndrome (MFS) in southern China and compare them with those presenting in other countries.

METHODS

We collected the medical records of patients diagnosed with MFS during 2013-2016. We analyzed the age, sex, onset season, precursor events, clinical symptoms and signs, findings of nerve conduction studies (NCS), cerebrospinal fluid (CSF), therapeutic remedies, nadir time, and length of hospital stay of patients with MFS in southern China. We concurrently compared the differences between urban and rural areas and between patients with incomplete ophthalmoplegia (IO) and complete ophthalmoplegia (CO).

RESULTS

The study enrolled 72 patients: 36 from rural areas and 36 from urban areas, and 50 males and 22 females. The mean age at onset was 47.72 years, and 30 (41.7%) and 21 (29.2%) patients developed MFS in spring and winter, respectively. The typical triad of ophthalmoplegia, ataxia, and areflexia was observed in 50 (69.4%) patients. A history of upper respiratory tract infection 1 week before onset was found in 52.8% of the patients, while 5.6% experienced gastrointestinal infections and 48 (73.8%) exhibited albuminocytological dissociation in the CSF study. Only 26 (36.1%) patients presented abnormalities in NCS. Moreover, restricted outward eyeball movement presented in 83.5% of the patients with classic MFS and acute ophthalmoplegia, and bilateral symmetrical ophthalmoplegia presented in 64.2%. With the exception of the higher proportion of NCS abnormalities in urban areas (47.2% vs. 25.0%), urban and rural differences were insignificant regarding sex ratio, age at onset, high-incidence season, precursor events, disease characteristics, and albuminocytological dissociation in the CSF. Furthermore, patients with CO were older than those with IO (64.53±7.69 vs. 43.19±14.40 years [mean±standard deviation], p<0.001).

CONCLUSIONS

The patients with MFS were mostly male and middle-aged, and most presented in winter and (especially) spring. More than half of the patients had clear precursor events, most of which were classic MFS with the typical triad. More than 70% of the patients presented albuminocytological dissociation in the CSF. NCS abnormalities were uncommon in MFS. The age at onset was lower in patients with IO than in patients with CO; bilateral symmetrical extraocular muscle paralysis was the most common symptom, and the external rectus was the most frequently involved muscle.

Neuron-Schwann cell interactions in peripheral nervous system homeostasis, disease, and preclinical treatment

Schwann cells (SCs) have a critical role in the peripheral nervous system. These cells are able to support axons during homeostasis and after injury. However, mutations in genes associated with the SCs repair program or myelination result in dysfunctional SCs. Several neuropathies such as Charcot-Marie-Tooth (CMT) disease, diabetic neuropathy and Guillain-Barré syndrome show abnormal SC functions and an impaired regeneration process. Thus, understanding SCs-axon interaction and the nerve environment in the context of homeostasis as well as post-injury and disease onset is necessary. Several neurotrophic factors, cytokines, and regulators of signaling pathways associated with proliferation, survival and regeneration are involved in this process. Preclinical studies have focused on the discovery of therapeutic targets for peripheral neuropathies and injuries. To study the effect of new therapeutic targets, modeling neuropathies and peripheral nerve injuries (PNIs) in vitro and in vivo are useful tools. Furthermore, several in vitro protocols have been designed using SCs and neuron cell lines to evaluate these targets in the regeneration process. SCs lines have been used to generate effective myelinating SCs without success. Alternative options have been investigated using direct conversion from somatic cells to SCs or SCs derived from pluripotent stem cells to generate functional SCs. This review will go over the advantages of these systems and the problems associated with them. In addition, there have been challenges in establishing adequate and reproducible protocols in vitro to recapitulate repair SC-neuron interactions observed in vivo. So, we also discuss the mechanisms of repair SCs-axon interactions in the context of peripheral neuropathies and nerve injury (PNI) in vitro and in vivo. Finally, we summarize current preclinical studies evaluating transgenes, drug, and novel compounds with translational potential into clinical studies.

Clinical and pathophysiological implications of autoantibodies in autoimmune neuropathies

Autoimmune neuropathies are a heterogeneous group of rare and disabling diseases in which the immune system targets peripheral nervous system antigens and that respond to immune therapies. This review focuses on Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy, multifocal motor neuropathy, polyneuropathy associated with IgM monoclonal gammopathy, and autoimmune nodopathies. Autoantibodies targeting gangliosides, proteins in the node of Ranvier, and myelin-associated glycoprotein have been described in these disorders, defining subgroups of patients with similar clinical features and response to therapy. This topical review describes the role of these autoantibodies in the pathogenesis of autoimmune neuropathies and their clinical and therapeutic importance.

Hospital-diagnosed morbidities and recent surgery as risk factors for developing Guillain-Barré syndrome

BACKGROUND AND PURPOSE

This study was undertaken to determine the association of hospital-diagnosed morbidity and recent surgery with risk of subsequent Guillain-Barré syndrome (GBS) development.

METHODS

We conducted a nationwide population-based case-control study of all patients with first-time hospital-diagnosed GBS in Denmark between 2004 and 2016 and 10 age-, sex-, and index date-matched population controls per case. Hospital-diagnosed morbidities included in the Charlson Comorbidity Index were assessed as GBS risk factors up to 10 years prior to the GBS index date. Incident major surgery was assessed within 5 months prior.

RESULTS

In the 13-year study period, there were 1086 incident GBS cases, whom we compared with 10,747 matched controls. Any pre-existing hospital-diagnosed morbidity was observed in 27.5% of GBS cases and 20.0% of matched controls, yielding an overall matched odds ratio (OR) of 1.6 (95% confidence interval [CI] = 1.4-1.9). The strongest associations were found for leukemia, lymphoma, diabetes, liver disease, myocardial infarction, congestive heart failure, and cerebrovascular disease, with 1.6- to 4.6-fold increased risks of subsequent GBS. GBS risk was strongest for morbidities newly diagnosed during the past 5 months (OR = 4.1, 95% CI = 3.0-5.6). Surgical procedures within 5 months prior were observed in 10.6% of cases and 5.1% of controls, resulting in a GBS OR of 2.2 (95% CI = 1.8-2.7). Risk of developing GBS was highest during the first month following surgery (OR = 3.7, 95% CI = 2.6-5.2).

CONCLUSIONS

In this large nationwide study, individuals with hospital-diagnosed morbidity and recent surgery had a considerably increased risk of GBS.

An Analysis of Respiratory Muscle Paralysis of Adult Patients in Guillain-Barré Syndrome: A Retrospective Analysis

Respiratory muscle paralysis is known as a very common complication of Guillain-Barré syndrome (GBS). However, most research has focused on its later stages rather than its earlier stages, including the prognosis of patients with this condition, or factors that act as early predictors of risk. Therefore, our study aimed to identify early predictors of respiratory muscle paralysis in patients with GBS and determine the short-term prognosis of such patients. We recruited 455 GBS patients (age ≥ 18) who had been hospitalized in the First Affiliated Hospital of Harbin Medical University between 2016 and 2021, retrospectively. We recorded clinical and laboratory data and used linear and logistic regression analysis to investigate the relationship between early clinical, examination results, and subsequent respiratory muscle paralysis. Among the 455 patients, 129 were assigned to a respiratory muscle paralysis group and 326 were assigned to a non-respiratory muscle paralysis group. Compared with the non-affected group, the time from onset to admission was shorter (p = 0.0003), and the Medical Research Council (MRC) score at admission and discharge was smaller in the affected group (p < 0.0001). Compared with the non-affected group, the affected group had higher Hughes and Erasmus GBS Respiratory Insufficiency Score (EGRIS) scores at admission and longer hospital stays (p < 0.0001). Patients in the affected group were more likely to have bulbar palsy and lung infections (p < 0.0001). To conclude, bulbar palsy, a higher EGRIS score and Hughes score at admission, a lower MRC score, and a shorter time between onset and admission, are all predictive risk factors for respiratory muscle paralysis in patients with GBS. An increase in any of these factors increases the risk of muscle paralysis. Patients with respiratory muscle paralysis have a poorer short-term prognosis than those without respiratory muscle paralysis. Therefore, we should attempt to identify patients with one or more of these characteristics in the early stages of admission, provide ventilation management, and administer IMV treatment if necessary.

Emerging biomarkers to predict clinical outcomes in Guillain-Barré syndrome

INTRODUCTION

Guillain-Barré syndrome (GBS) is an immune-mediated poly(radiculo)neuropathy with a variable clinical outcome. Identifying patients who are at risk of suffering from long-term disabilities is a great challenge. Biomarkers are useful to confirm diagnosis, monitor disease progression, and predict outcome.

AREAS COVERED

The authors provide an overview of the diagnostic and prognostic biomarkers for GBS, which are useful for establishing early treatment strategies and follow-up care plans.

EXPERT OPINION

Detecting patients at risk of developing a severe outcome may improve management of disease progression and limit potential complications. Several clinical factors are associated with poor prognosis: higher age, presence of diarrhea within 4 weeks of symptom onset, rapid and severe weakness progression, dysautonomia, decreased vital capacity and facial, bulbar, and neck weakness. Biological, neurophysiological and imaging measures of unfavorable outcome include multiple anti-ganglioside antibodies elevation, increased serum and CSF neurofilaments light (NfL) and heavy chain, decreased NfL CSF/serum ratio, hypoalbuminemia, nerve conduction study with early signs of demyelination or axonal loss and enlargement of nerve cross-sectional area on ultrasound. Depicting prognostic biomarkers aims at predicting short-term mortality and need for cardio-pulmonary support, long-term patient functional outcome, guiding treatment decisions and monitoring therapeutic responses in future clinical trials.

COVID-19 as a trigger of Guillain-Barré syndrome: A review of the molecular mechanism

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a pandemic with serious complications. After coronavirus disease 2019 (COVID-19), several post-acute COVID-19 syndromes (PACSs) and long-COVID sequels were reported. PACSs involve many organs, including the nervous, gustatory, and immune systems. One of the PACSs after SARS-CoV-2 infection and vaccination is Guillain-Barré syndrome (GBS). The incidence rate of GBS after SARS-CoV-2 infection or vaccination is low. However, the high prevalence of COVID-19 and severe complications of GBS, for example, autonomic dysfunction and respiratory failure, highlight the importance of post-COVID-19 GBS. It is while patients with simultaneous COVID-19 and GBS seem to have higher admission rates to the intensive care unit, and demyelination is more aggressive in post-COVID-19 GBS patients. SARS-CoV-2 can trigger GBS via several pathways like direct neurotropism and neurovirulence, microvascular dysfunction and oxidative stress, immune system disruption, molecular mimicry, and autoantibody production. Although there are few molecular studies on the molecular and cellular mechanisms of GBS occurrence after SARS-CoV-2 infection and vaccination, we aimed to discuss the possible pathomechanism of post-COVID-19 GBS by gathering the most recent molecular evidence.

Single-cell analysis reveals novel clonally expanded monocytes associated with IL1β-IL1R2 pair in acute inflammatory demyelinating polyneuropathy

Guillain-Barré syndrome (GBS) is an autoimmune disorder wherein the composition and gene expression patterns of peripheral blood immune cells change significantly. It is triggered by antigens with similar epitopes to Schwann cells that stimulate a maladaptive immune response against peripheral nerves. However, an atlas for peripheral blood immune cells in patients with GBS has not yet been constructed. This is a monocentric, prospective study. We collected 5 acute inflammatory demyelinating polyneuropathy (AIDP) patients and 3 healthy controls hospitalized in the First Affiliated Hospital of Harbin Medical University from December 2020 to May 2021, 3 AIDP patients were in the peak stage and 2 were in the convalescent stage. We performed single-cell RNA sequencing (scRNA-seq) of peripheral blood mononuclear cells (PBMCs) from these patients. Furthermore, we performed cell clustering, cell annotation, cell-cell communication, differentially expressed genes (DEGs) identification and pseudotime trajectory analysis. Our study identified a novel clonally expanded CD14+ CD163+ monocyte subtype in the peripheral blood of patients with AIDP, and it was enriched in cellular response to IL1 and chemokine signaling pathways. Furthermore, we observed increased IL1β-IL1R2 cell-cell communication between CD14+ and CD16+ monocytes. In short, by analyzing the single-cell landscape of the PBMCs in patients with AIDP we hope to widen our understanding of the composition of peripheral immune cells in patients with GBS and provide a theoretical basis for future studies.

Is there a causal nexus between COVID-19 infection, COVID-19 vaccination, and Guillain-Barré syndrome?

Guillain-Barré syndrome (GBS) is an immune-mediated inflammatory polyradiculoneuropathy, which commonly leads to a very high level of neurological disability. Especially, after the global outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the causation between GBS and SARS-CoV-2 infection and the coronavirus disease 2019 (COVID-19) vaccination have aroused widespread concern. In the review, we analyzed the impacts of SARS-CoV-2 infection and COVID-19 vaccination on GBS globally, aiming to further understand the characteristics of GBS associated with COVID-19. Based on the electrophysiological data, patients suffering from GBS related to COVID-19 manifested as an acute inflammatory demyelinating polyneuropathy (AIDP). Moreover, we summarized the current findings, which may evidence GBS linking to SARS-CoV-2 infection and COVID-19 vaccination, and discussed the underlying mechanisms whether and how the SARS-CoV-2 virus and COVID-19 vaccination can induce GBS and its variants.

Molecular Targets in Campylobacter Infections

Human campylobacteriosis results from foodborne infections with Campylobacter bacteria such as Campylobacter jejuni and Campylobacter coli, and represents a leading cause of bacterial gastroenteritis worldwide. After consumption of contaminated poultry meat, constituting the major source of pathogenic transfer to humans, infected patients develop abdominal pain and diarrhea. Post-infectious disorders following acute enteritis may occur and affect the nervous system, the joints or the intestines. Immunocompromising comorbidities in infected patients favor bacteremia, leading to vascular inflammation and septicemia. Prevention of human infection is achieved by hygiene measures focusing on the reduction of pathogenic food contamination. Molecular targets for the treatment and prevention of campylobacteriosis include bacterial pathogenicity and virulence factors involved in motility, adhesion, invasion, oxygen detoxification, acid resistance and biofilm formation. This repertoire of intervention measures has recently been completed by drugs dampening the pro-inflammatory immune responses induced by the Campylobacter endotoxin lipo-oligosaccharide. Novel pharmaceutical strategies will combine anti-pathogenic and anti-inflammatory effects to reduce the risk of both anti-microbial resistance and post-infectious sequelae of acute enteritis. Novel strategies and actual trends in the combat of Campylobacter infections are presented in this review, alongside molecular targets applied for prevention and treatment strategies.

Conformational dynamics and putative substrate extrusion pathways of the N-glycosylated outer membrane factor CmeC from Campylobacter jejuni

The outer membrane factor CmeC of the efflux machinery CmeABC plays an important role in conferring antibiotic and bile resistance to Campylobacter jejuni. Curiously, the protein is N-glycosylated, with the glycans playing a key role in the effective function of this system. In this work we have employed atomistic equilibrium molecular dynamics simulations of CmeC in a representative model of the C. jejuni outer membrane to characterise the dynamics of the protein and its associated glycans. We show that the glycans are more conformationally labile than had previously been thought. The extracellular loops of CmeC visit the open and closed states freely suggesting the absence of a gating mechanism on this side, while the narrow periplasmic entrance remains tightly closed, regulated via coordination to solvated cations. We identify several cation binding sites on the interior surface of the protein. Additionally, we used steered molecular dynamics simulations to elucidate translocation pathways for a bile acid and a macrolide antibiotic. These, and additional equilibrium simulations suggest that the anionic bile acid utilises multivalent cations to climb the ladder of acidic residues that line the interior surface of the protein.

Sex differences in Guillain Barré syndrome, chronic inflammatory demyelinating polyradiculoneuropathy and experimental autoimmune neuritis

Guillain Barré syndrome (GBS) and its variants, and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP and its variants, are regarded as immune mediated neuropathies. Unlike in many autoimmune disorders, GBS and CIDP are more common in males than females. Sex is not a clear predictor of outcome. Experimental autoimmune neuritis (EAN) is an animal model of these diseases, but there are no studies of the effects of sex in EAN. The pathogenesis of GBS and CIDP involves immune response to non-protein antigens, antigen presentation through non-conventional T cells and, in CIDP with nodopathy, IgG4 antibody responses to antigens. There are some reported sex differences in some of these elements of the immune system and we speculate that these sex differences could contribute to the male predominance of these diseases, and suggest that sex differences in peripheral nerves is a topic worthy of further study.

Extracellular Vesicles in Chronic Demyelinating Diseases: Prospects in Treatment and Diagnosis of Autoimmune Neurological Disorders

Extracellular vesicles (EVs) represent membrane-enclosed structures that are likely to be secreted by all living cell types in the animal organism, including cells of peripheral (PNS) and central nervous systems (CNS). The ability to cross the blood-brain barrier (BBB) provides the possibility not only for various EV-loaded molecules to be delivered to the brain tissues but also for the CNS-to-periphery transmission of these molecules. Since neural EVs transfer proteins and RNAs are both responsible for functional intercellular communication and involved in the pathogenesis of neurodegenerative diseases, they represent attractive diagnostic and therapeutic targets. Here, we discuss EVs' role in maintaining the living organisms' function and describe deviations in EVs' structure and malfunctioning during various neurodegenerative diseases.

Guillain-Barré Syndrome in Northern China: A Retrospective Analysis of 294 Patients from 2015 to 2020

Objectives: Acute motor axonal neuropathy (AMAN) was first reported to be the main subtype of Guillain−Barré syndrome (GBS) in northern China in the 1990s. About 30 years has passed, and it is unknown whether the disease spectrum has changed over time in northern China. We aimed to study the epidemiological, clinical, and electrophysiological features of GBS in northern China in recent years. Methods: We retrospectively analyzed the medical records of GBS patients admitted to the Second Hospital of Hebei Medical University in northern China from 2015 to 2020. Results: A total of 294 patients with GBS were enrolled, with median age 53 years and 60.5% of participants being male, and a high incidence in summer and autumn. AMAN was still the predominant subtype in northern China (40.1%). The AMAN patients had shorter time to nadir, longer hospitalization time, and a more severe HFGS score at discharge than acute inflammatory demyelinating polyneuropathies (AIDP) (p < 0.05). With SPSS multivariable logistic regression analysis, we found the GBS disability score (at admission), dysphagia, and dysautonomia were independent risk factors for GBS patients requiring MV (p < 0.05). In comparison with other regions, the proportion of AMAN in northern China (40.1%) was higher than in eastern (35%) and southern (19%) China. Conclusions: AMAN is still the predominant subtype in northern China after 30 years, but there have been changes over time in the GBS spectrum since the 1990s. There are regional differences in GBS in China.

Campylobacter jejuni and Postinfectious Autoimmune Diseases: A Proof of Concept in Glycobiology

Glycans, one of the most diverse groups of macromolecules, are ubiquitous constituents of all cells and have many critical functions, including the interaction between microbes and their hosts. One of the best model organisms to study the host-pathogen interaction, the gastrointestinal pathogen Campylobacter jejuni dedicates extensive resources to glycosylation and exhibits a diverse array of surface sugar-coated displays. The first bacterium where N-linked glycosylation was described, C. jejuni can additionally modify proteins by O-linked glycosylation, has extracellular capsular polysaccharides that are important for virulence and represent the major determinant of the Penner serotyping scheme, and has outer membrane lipooligosaccharides that participate in processes such as colonization, survival, inflammation, and immune evasion. In addition to causing gastrointestinal disease and extraintestinal infections, C. jejuni was also linked to postinfectious autoimmune neuropathies, of which Guillain-Barré syndrome (GBS) and Miller Fisher syndrome (MFS) are the most extensively characterized ones. These postinfectious autoimmune neuropathies occur when specific bacterial surface lipooligosaccharides mimic gangliosides in the host nervous system. C. jejuni provided the first proof of concept for the involvement of molecular mimicry in the pathogenesis of an autoimmune disease and, also, for the ability of a bacterial polymorphism to shape the clinical presentation of the postinfectious autoimmune neuropathy. The scientific journey that culminated with elucidating the mechanistic details of the C. jejuni-GBS link was the result of contributions from several fields, including microbiology, structural biology, glycobiology, genetics, and immunology and provides an inspiring and important example to interrogate other instances of molecular mimicry and their involvement in autoimmune disease.

COVID-19 Vaccination a Cause of Guillain-Barré Syndrome? A Case Series

Guillain-Barré syndrome (GBS) is a rare autoimmune neuropathic disorder of peripheral nerves usually following an infection or on rarer occasions following vaccinations, but the exact underlying pathophysiology is still unclear. The most common etiology of GBS is a bacterial infection caused by Campylobacter jejuni. Viral infections like Zika virus, Epstein-Barr virus, and Cytomegalovirus also add to the list of GBS etiology. COVID-19 (SARS-CoV-2) has also been reported to cause GBS. Vaccines like the rabies vaccine, influenza vaccine, and poliovirus vaccine account for a very small fraction of Guillain-Barré syndrome. GBS as an adverse effect of COVID-19 vaccination was not reported by the Vaccine Adverse Event Reporting System (VAERS), but an update was later released in the course of the pandemic from FDA news, reporting several patients developing GBS after receiving the COVID-19 vaccine. In this case series, we discuss five cases that developed the GBS post-COVID-19 AstraZeneca vaccine, along with its pathophysiology, management, and outcome.

Bacterial glycosylation, it’s complicated

Each microbe has the ability to produce a wide variety of sugar structures that includes some combination of glycolipids, glycoproteins, exopolysaccharides and oligosaccharides. For example, bacteria may synthesize lipooligosaccharides or lipopolysaccharides, teichoic and lipoteichoic acids, N- and O-linked glycoproteins, capsular polysaccharides, exopolysaccharides, poly-N-acetylglycosamine polymers, peptidoglycans, osmoregulated periplasmic glucans, trehalose or glycogen, just to name a few of the more broadly distributed carbohydrates that have been studied. The composition of many of these glycans are typically dissimilar from those described in eukaryotes, both in the seemingly endless repertoire of sugars that microbes are capable of synthesizing, and in the unique modifications that are attached to the carbohydrate residues. Furthermore, strain-to-strain differences in the carbohydrate building blocks used to create these glycoconjugates are the norm, and many strains possess additional mechanisms for turning on and off transferases that add specific monosaccharides and/or modifications, exponentially contributing to the structural heterogeneity observed by a single isolate, and preventing any structural generalization at the species level. In the past, a greater proportion of research effort was directed toward characterizing human pathogens rather than commensals or environmental isolates, and historically, the focus was on microbes that were simple to grow in large quantities and straightforward to genetically manipulate. These studies have revealed the complexity that exists among individual strains and have formed a foundation to better understand how other microbes, hosts and environments further transform the glycan composition of a single isolate. These studies also motivate researchers to further explore microbial glycan diversity, particularly as more sensitive analytical instruments and methods are developed to examine microbial populations in situ rather than in large scale from an enriched nutrient flask. This review emphasizes many of these points using the common foodborne pathogen Campylobacter jejuni as the model microbe.

Understanding the Tissue Specificity of ZIKV Infection in Various Animal Models for Vaccine Development

Zika virus (ZIKV) is an arthropod-borne virus that belongs to the Flavivirus genus and is principally transmitted by Aedes aegypti mosquitoes. ZIKV infection often causes no or only mild symptoms, but it can also trigger severe consequences, including microcephaly in infants and Guillain-Barré syndrome, uveitis, and neurologic manifestations in adults. There is no ZIKV vaccine or treatment currently approved for clinical use. The primary target of ZIKV infection has been recognized as the maternal placenta, with vertical transmission to the fetal brain. However, ZIKV can also spread to multiple tissues in adults, including the sexual organs, eyes, lymph nodes, and brain. Since numerous studies have indicated that there are slightly different tissue-specific pathologies in each animal model of ZIKV, the distinct ZIKV tropism of a given animal model must be understood to enable effective vaccine development. Here, we comprehensively discussed the tissue specificity of ZIKV reported in each animal model depending on the genetic background and route of administration. This review should facilitate the selection of appropriate animal models when studying the fundamental pathogenesis of ZIKV infection, thereby supporting the design of optimal preclinical and clinical studies for the development of vaccines and therapeutics.

[Introduction to Myelin Research]

Myelin is a multilamellar membrane structure formed by oligodendrocytes in the central nervous system (CNS) and Schwann cells in the peripheral nervous system (PNS). It has been recognized as an insulator that is essential for the rapid and efficient propagation of action potentials by saltatory conduction. However, recently many studies have shown that myelin and myelin-forming cells interact with axons and regulate the nervous system far more actively than previously thought. For example, myelination changes axons dynamically and divides them into four distinct functional domains: node of Ranvier, paranode, juxtaparanode, and internode. Voltage-gated Na⁺ channels are clustered at the node, while K⁺ channels are at the juxtaparanode, and segregation of these channels by paranodal axoglial junction is necessary for proper axonal function. My research experience began at the neurology ward of the Niigata University Medical Hospital, where I saw a patient with peripheral neuropathy of unknown etiology more than 37 years ago. In the patient's serum, we found an autoantibody against a glycolipid enriched in the PNS. Since then, I have been interested in myelin because of its beautiful structure and unique roles in the nervous system. In this review, our recent studies related to CNS and PNS myelin are presented.

The outcome of Guillain-Barré syndrome following intravenous immunoglobulin compared to the natural course

BACKGROUND

Intravenous immunoglobulin (IVIg) is recommended in Guillain-Barré syndrome (GBS), but its efficacy may vary in different subtypes. We report the outcomes of patients with GBS following IVIg treatment compared to the natural course (NC). We also compare the effect of IVIg treatment in different subtypes of GBS.

METHODS

From a cohort of 528 GBS, we have extracted 189 patients who received IVIg and compared their outcomes with 199 age and peak disability matched patients who did not receive IVIg, plasmapheresis, or corticosteroid. Disability was assessed using the 0-6 GBS Disability Scale (GBSDS). Clinical and neurophysiological subtypes were recorded. The primary outcome was functional disability at 6-months and was categorized as complete (GBSDS ≤ 1), partial (GBSDS 2-3), and poor (GBSDS > 3). The secondary outcomes were in-hospital death, and duration of hospitalization, and mechanical ventilation (MV).

RESULTS

In-hospital death (2.6% vs 2%; p = 0.74) and 3-months poor recovery (20.7% vs 18%) were similar in the IVIg and NC group. At 6-months, however, a lesser proportion of patients in IVIg group had poor recovery (2.2% vs 8.3%; p = 0.026). The outcomes of IVIg and NC were compared in 72 AMAN and 256 AIDP patients. IVIg therapy did not alter the outcome in AMAN but resulted in a lesser proportion of poor recovery at 6-months in AIDP (0.8% vs. 6.6%; p = 0.03).

CONCLUSION

Intravenous immunoglobulin is beneficial in AIDP variants of GBS but not in the AMAN subtype. A customized treatment may be cost-effective till a randomized controlled trial is conducted in AMAN.

Axonal pathology in early stages of Guillain-Barré syndrome

INTRODUCTION

Guillain-Barré syndrome (GBS) is an acute-onset, immune-mediated disease of the peripheral nervous system. It may be classified into 2 main subtypes: demyelinating (AIDP) and axonal (AMAN). This study aims to analyse the mechanisms of axonal damage in the early stages of GBS (within 10 days of onset).

DEVELOPMENT

We analysed histological, electrophysiological, and imaging findings from patients with AIDP and AMAN, and compared them to those of an animal model of myelin P2 protein-induced experimental allergic neuritis. Inflammatory oedema of the spinal nerve roots and spinal nerves is the initial lesion in GBS. The spinal nerves of patients with fatal AIDP may show ischaemic lesions in the endoneurium, which suggests that endoneurial inflammation may increase endoneurial fluid pressure, reducing transperineurial blood flow, potentially leading to conduction failure and eventually to axonal degeneration. In patients with AMAN associated with anti-ganglioside antibodies, nerve conduction block secondary to nodal sodium channel dysfunction may affect the proximal, intermediate, and distal nerve trunks. In addition to the mechanisms involved in AIDP, active axonal degeneration in AMAN may be associated with nodal axolemma disruption caused by anti-ganglioside antibodies.

CONCLUSION

Inflammatory oedema of the proximal nerve trunks can be observed in early stages of GBS, and it may cause nerve conduction failure and active axonal degeneration.

Axonal pathology in early stages of Guillain-Barré syndrome

INTRODUCTION

Guillain-Barré syndrome (GBS) is an acute-onset, immune-mediated disease of the peripheral nervous system. It may be classified into 2 main subtypes: demyelinating (AIDP) and axonal (AMAN). This study aims to analyse the mechanisms of axonal damage in the early stages of GBS (within 10days of onset).

DEVELOPMENT

We analysed histological, electrophysiological, and imaging findings from patients with AIDP and AMAN, and compared them to those of an animal model of myelin P2 protein-induced experimental allergic neuritis. Inflammatory oedema of the spinal nerve roots and spinal nerves is the initial lesion in GBS. The spinal nerves of patients with fatal AIDP may show ischaemic lesions in the endoneurium, which suggests that endoneurial inflammation may increase endoneurial fluid pressure, reducing transperineurial blood flow, potentially leading to conduction failure and eventually to axonal degeneration. In patients with AMAN associated with anti-ganglioside antibodies, nerve conduction block secondary to nodal sodium channel dysfunction may affect the proximal, intermediate, and distal nerve trunks. In addition to the mechanisms involved in AIDP, active axonal degeneration in AMAN may be associated with nodal axolemma disruption caused by anti-ganglioside antibodies.

CONCLUSION

Inflammatory oedema of the proximal nerve trunks can be observed in early stages of GBS, and it may cause nerve conduction failure and active axonal degeneration.

Characterization of Guillain-Barré Syndrome in the integrated development region of the Federal District and Surrounding Areas (RIDE), Brazil, between 2017 and 2019

INTRODUCTION

Guillain-Barré Syndrome (GBS) is an acute immune-mediated polyneuropathy that primarily affects the peripheral nerves. Following the Zika virus outbreak in Latin America, all the Latin American and Brazilian studies conducted reported an increase in the incidence of GBS. The present study aims to characterize the clinical and demographic profile of patients with GBS, according to electrophysiological estudies.

METHODS

This is a clinical cohort study based on data from medical charts and interviews conducted at the homes of GBS cases identified by three data sources, admitted to and treated at a tertiary referral hospital between March 2017 and May 2019.

RESULTS

There was a high level of diagnostic certainty among the 51 GBS cases monitored, with most classified as exhibiting acute inflammatory demyelinating polyneuropathy (AIDP). The majority of the individuals were of working age, with an average schooling level. Diarrhea and upper respiratory tract infection were the previous events most reported. Most cases were admitted to the hospital unable to walk and the main complication identified was aspiration pneumonia.

CONCLUSION

The findings indicate the need to rethink the care of patients with GBS in order to minimize the possibility of future complications during hospitalization that may lead to unfavorable outcomes.

Frequency of exposure to arboviruses and characterization of Guillain Barré syndrome in a clinical cohort of patients treated at a tertiary referral center in Brasília, Federal District

Background:

Guillian Barré syndrome (GBS) is an acute autoimmune polyradiculoneuropathy often associated with previous exposure to infectious agents.

Methods:

A clinical cohort of 41 patients with GBS admitted to the Base Hospital Institute of the Federal District between May 2017 and April 2019 was followed up for 1 year. Serological tests for arbovirus detection and amplification of nucleic acids using polymerase chain reaction for zika virus (ZIKV), dengue virus (DENV), and chikungunya virus (CHIKV) were performed.

Results:

The cohort consisted of 61% men with a median age of 40 years, and 83% had GBS-triggering events. A total of 54% had Grade 4 disability, 17% had Grade 3, 12% had Grade 2, 10% had Grade 5, and 7% had Grade 1. The classic form occurred in 83% of patients. Nerve conduction evaluations revealed acute demyelinating inflammatory polyneuropathy (51%), acute motor axonal neuropathy (17%), acute sensory-motor neuropathy (15%), and indeterminate forms (17%). Four patients were seropositive for DENV. There was no laboratory detection of ZIKV or CHIKV infection. Ninety percent of patients received human immunoglobulin. Intensive care unit admission occurred in 17.1% of the patients, and mechanical ventilation was used in 14.6%. One patient died of Bickerstaff’s encephalitis. Most patients showed an improvement in disability at 10 weeks of follow-up.

Conclusions:

GBS in the Federal District showed a variable clinical spectrum, and it was possible to detect recent exposure to DENV.

Durvalumab-Induced Demyelinating Lesions in a Patient With Extensive-Stage Small-Cell Lung Cancer: A Case Report

It is of great clinical value to investigate the immune-related adverse events (irAEs), especially demyelinating lesions, caused by immune checkpoint inhibitors (ICIs). The incidence of demyelinating lesions is less frequent in irAEs, but once it occurs, it will seriously affect the survival of patients. The present study reports a case of durvalumab-induced demyelinating lesions in a patient with extensive-stage small-cell lung cancer. Subsequently, the patient receives a high intravenous dose of methylprednisolone and his condition is improved after 21 days of treatment. Altogether, early diagnosis and treatment of ICIs-related neurological irAEs is of great significance to the outcome of the patient’s condition.

[Pathophysiological and diagnostic aspects of Guillain-Barré syndrome]

Guillain-Barré syndrome (GBS) is the most common cause of acute neuropathy. It usually onset with a rapidly progressive ascending bilateral weakness with sensory disturbances, and patients may require intensive treatment and close monitoring as about 30% have a respiratory muscle weakness and about 10% have autonomic dysfunction. The diagnosis of GBS is based on clinical history and examination. Complementary examinations are performed to rule out a differential diagnosis and to secondarily confirm the diagnosis. GBS is usually preceded by an infectious event in ≈ 2/3 of cases. Infection leads to an immune response directed against carbohydrate antigens located on the infectious agent and the formation of anti-ganglioside antibodies. By molecular mimicry, these antibodies can target structurally similar carbohydrates found on host's nerves. Their binding results in nerve conduction failure or/and demyelination which can lead to axonal loss. Some anti-ganglioside antibodies are associated with particular variants of GBS: the Miller-Fisher syndrome, facial diplegia and paresthesias, the pharyngo-cervico-brachial variant, the paraparetic variant, and the Bickerstaff brainstem encephalitis. Their semiological differences might be explained by a distinct expression of gangliosides among nerves. The aim of this review is to present pathophysiological aspects and the diagnostic approach of GBS and its variants.

Association between serum low-density neutrophils and acute-onset and recurrent Guillain-Barré syndrome

BACKGROUND AND AIM

Guillain-Barré syndrome (GBS) is one of the most common causes of acute flaccid paralysis. A timely assessment of this disease condition and its treatments are of vital importance to patients diagnosed with GBS. The purpose of this study is to investigate the variation trend of neutrophils along with disease courses and assess the prognostic value of serum low-density neutrophils (LDNs) in the acute-onset and recurrence of GBS.

METHODS

A total of 176 GBS patients were recruited. Patients were evaluated with Medical Research Council (MRC) sum score and the Hughes Functional Grading Scale score upon admission. Peripheral blood samples were collected for routine testing. Flow cytometry analysis was performed to identify LDNs. All patients were followed up to collect disease condition data.

RESULTS

The total neutrophil ratios and counts were significantly higher in patients with acute-onset GBS compared to healthy controls (HCs). These counts/ratios decreased during remission and re-elevated in recurrent GBS patients. However, no correlation was observed between the total neutrophil counts/ratios and the MRC sum score. The LDNs collected from different GBS courses were identified using flow cytometry. The counts and ratios were significantly higher in acute-onset GBS and recurrent GBS compared to HCs and patients in remission. The LDN counts/ratios displayed a negative correlation with the MRC sum scores in acute-onset GBS and recurrent GBS.

CONCLUSION

Our findings suggest that LDN counts/ratios are positively correlated with the acute-onset and recurrence of GBS and its severity. Therefore, LDNs might serve as an accessible prognostic indicator for disease progression monitoring.

Anti-MAG neuropathy: From biology to clinical management

The acquired chronic demyelinating neuropathies include a growing number of disease entities that have characteristic, often overlapping, clinical presentations, mediated by distinct immune mechanisms, and responding to different therapies. After the discovery in the early 1980s, that the myelin associated glycoprotein (MAG) is a target antigen in an autoimmune demyelinating neuropathy, assays to measure the presence of anti-MAG antibodies were used as the basis to diagnose the anti-MAG neuropathy. The route was open for describing the clinical characteristics of this new entity as a chronic distal large fiber sensorimotor neuropathy, for studying its pathogenesis and devising specific treatment strategies. The initial use of chemotherapeutic agents was replaced by the introduction in the late 1990s of rituximab, a monoclonal antibody against CD20⁺ B-cells. Since then, other anti-B cells agents have been introduced. Recently a novel antigen-specific immunotherapy neutralizing the anti-MAG antibodies with a carbohydrate-based ligand mimicking the natural HNK-1 glycoepitope has been described.

Guillain-Barré Syndrome in an Elderly Patient as a Complication of COVID-19 Infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an infection that mainly affects the respiratory system. It may present with fever, fatigue, dry cough, and dyspnea. In addition, numerous studies and case reports discussed those viruses showing their effects on the nervous system. In this report, we present a case of a 66-year-old Saudi man who had been recovering from symptoms related to coronavirus 2019 (COVID-19) associated disease. He was presented with sudden progressive ascending weakness that started in the left leg, and it spread to involve both legs and then both arms, five days prior to hospitalization. Lumbar puncture and nerve conduction studies showed that the patient has an acute motor-sensory axonal neuropathy (AMSAN) variant of Guillain-Barré syndrome (GBS). The patient was treated with intravenous immunoglobulin (IVIG) and supportive care. The patient was discharged after 15 days of hospitalization with clinical improvement. In conclusion, to our knowledge, this study investigated the first reported case of GBS in an elderly patient as a complication of COVID-19 infection in Saudi Arabia, with the most severe variant AMSAN. As the COVID-19 pandemic continues, clinicians should consider GBS as a neurological complication of COVID-19, and therapy must be initiated. Further studies are needed to study the possible mechanism of GBS in patients with COVID-19 in the future.

Risk of progression to autoimmune disease in severe drug eruption: risk factors and the factor-guided stratification

The identification of risk factors is key not only to uncover the pathogenesis of autoimmune disease but also to predict progression to autoimmune disease. Drug-induced hypersensitivity syndrome (DiHS)/ drug reaction with eosinophilia and systemic symptoms (DRESS) is likely the best prototypic example for analyzing the sequential events. We conducted a retrospective study of 55 patients with DiHS/DRESS followed for the possibility of later development of autoimmune disease ∼18 years after resolution. Nine patients progressed to autoimmune sequelae regardless of treatment. The generation of autoantibodies preceded by 8 years in 8 of the 9 patients. The combination of increases in lymphocyte counts, severe liver damage, a rebound increase in globulin, persistent reactivations of Epstein-Barr virus and human herpesvirus-6, and low interleukin (IL)-2 and IL-4 at the acute/subacute phases, were significant risk factors for the future development of autoimmune disease. Based on these factors, we established a scoring system that can identify high-risk patients. When stratified these patients into three risk categories (low/intermediate/high), occurrence of autoimmune disease was exclusively detected in the high group. Our data represent the new scoring system to identify patients at high-risk of developing autoimmune disease, although a larger study is required to validate the scoring system.

Lactic Acid Bacteria - A Promising Tool for Controlling Chicken Campylobacter Infection

Since 2005, campylobacteriosis has been the most common zoonotic disease in Europe. The main reservoir of pathogenic Campylobacter strains is broilers, which makes raw and undercooked poultry meat two major sources of disease. Infection in chicken flocks is most often asymptomatic, despite a high level of colonization reaching 106-109cfu/g in animal ceca. It is widely believed that controlling the level of colonization of the birds' digestive tract by pathogenic strains is a good way to increase food safety. Many treatments have been proposed to combat or at least reduce the level of colonization in animals reservoirs: probiotics, bacteriophages, vaccines, and anti-Campylobacter bacteriocins. This review focuses on the effects of Campylobacter infection on the chicken microbiome and colonization control strategies using probiotics (mostly lactic acid bacteria, LAB), which are live microorganisms included in the diet of animals as feed additives or supplements. Probiotics are not only an alternative to antibiotics, which were used for years as animal growth promoters, but they also constitute an effective protective barrier against excessive colonization of the digestive system by pathogenic bacteria, including Campylobacter. Moreover, one of the many beneficial functions of probiotics is the ability to manipulate the host's microbiota. Recently, there have also been some promising attempts to use lactic acid bacteria as a delivery system of oral vaccine against Campylobacter. Recombinant LAB strains induce primarily a mucosal immune response against foreign antigens, accompanied by at most a low-level immune response against carrier strains. Since the main barrier against the invasion of pathogens in the gastrointestinal tract is the intestinal mucosal membrane, the development of effective oral vaccines to protect animals against enteric infection is very reasonable.

Modified recombinant human IgG1-Fc is superior to natural intravenous immunoglobulin at inhibiting immune-mediated demyelination

Intravenous immunoglobulin (IVIG) is an established treatment for numerous autoimmune conditions. Although Fc fragments derived from IVIG have shown efficacy in controlling immune thrombocytopenia in children, the mechanisms of action are unclear and controversial. The aim of this study was to dissect IVIG effector mechanisms using further adapted Fc fragments on demyelination in an ex vivo model of the central nervous system-immune interface. Using organotypic cerebellar slice cultures (OSCs) from transgenic mice, we induced extensive immune-mediated demyelination and oligodendrocyte loss with an antibody specific for myelin oligodendrocyte glycoprotein (MOG) and complement. Protective effects of adapted Fc fragments were assessed by live imaging of green fluorescent protein expression, immunohistochemistry and confocal microscopy. Cysteine- and glycan-adapted Fc fragments protected OSC from demyelination in a dose-dependent manner where equimolar concentrations of either IVIG or control Fc were ineffective. The protective effects of the adapted Fc fragments are partly attributed to interference with complement-mediated oligodendroglia damage. Transcriptome analysis ruled out signatures associated with inflammatory or innate immune responses. Taken together, our findings show that recombinant biomimetics can be made that are at least two hundred-fold more effective than IVIG in controlling demyelination by anti-MOG antibodies.

Sydenham's chorea: from pathophysiology to therapeutics

Sydenham's chorea is an autoimmune chorea emerging after a group A beta-hemolytic streptococcal (GABHS) infection, i.e. a rheumatic chorea with or without the presence of carditis or arthritis. The disorder, defined by the presence of chorea, is also associated with cognitive and behavioral symptoms, including emotional lability, anxiety, depressive and obsessive-compulsive symptoms. The authors review the pathophysiology, clinical characteristics, and available evidence on therapeutic strategies, the latter including the secondary prevention of GABHS infections, reduction of chorea, and immune modulation. Sydenham's chorea has been regarded as a model for pediatric autoimmune neuropsychiatric disorders, however, the field is marked by conflicting results and controversies. Regarding therapeutics, there are limited high-quality interventional studies and the selection of treatment strategy often relies on the clinician's experience. A serial treatment algorithm is presented based upon the severity of clinical presentation and response to symptomatic pharmacotherapy.

Guillain-Barré Syndrome After Acute Hepatitis E Infection: A Case Report and Literature Review

INTRODUCTION

Guillain-Barré syndrome precipitated by hepatitis E virus infection is rare, yet its incidence is increasing.

CLINICAL FINDINGS

A 57-year-old man was transferred from another facility with fatigue, orange urine, and progressive weakness over 4 to 6 weeks. Initial laboratory results included total bilirubin, 9.0 mg/dL; direct bilirubin, 6.4 mg/dL; aspartate aminotransferase, 1551 U/L; alanine aminotransferase, 3872 U/L; and alkaline phosphatase, 430 U/L. Immunoglobulin M and quantitative polymerase chain reaction test results were positive for hepatitis E virus. Contrast-enhanced magnetic resonance imaging of the brain and spine showed no gross abnormalities. Analysis of cerebrospinal fluid obtained by lumbar puncture revealed the following (reference values in parentheses): total white blood cell count, 15/μL (0-5/μL), with 33% neutrophils and 54% lymphocytes; protein, 0.045 g/dL (0.015-0.045 g/dL); and glucose, 95 mg/dL (within reference range). Neurological examination revealed weakness in both upper extremities, with proximal strength greater than distal strength. The patient could not elevate either lower extremity off the bed and had areflexia and reduced sensation throughout all extremities.

DIAGNOSIS

Guillain-Barré syndrome secondary to acute hepatitis E virus infection was diagnosed on the basis of clinical characteristics, serum and cerebrospinal fluid analyses, and nerve conduction studies.

CONCLUSIONS

Nurses and clinicians should obtain a thorough history and consider hepatitis E virus infection as a precipitating factor in patients with sensory and motor disturbances consistent with Guillain-Barré syndrome. The case gives insight into the diagnostic process for Guillain-Barré syndrome and highlights the vital role of bedside nurses in evaluating and treating these patients.