Antibodies to gangliosides and galactocerebroside in patients with Guillain-Barré syndrome with preceding Campylobacter jejuni and other identified infections

Engineering Mycoplasma pneumoniae to bypass the association with Guillain-Barré syndrome

A non-pathogenic Mycoplasma pneumoniae-based chassis is leading the development of live biotherapeutic products (LBPs) for respiratory diseases. However, reports connecting Guillain-Barré syndrome (GBS) cases to prior M. pneumoniae infections represent a concern for exploiting such a chassis. Galactolipids, especially galactocerebroside (GalCer), are considered the most likely M. pneumoniae antigens triggering autoimmune responses associated with GBS development. In this work, we generated different strains lacking genes involved in galactolipids biosynthesis. Glycolipid profiling of the strains demonstrated that some mutants show a complete lack of galactolipids. Cross-reactivity assays with sera from GBS patients with prior M. pneumoniae infection showed that certain engineered strains exhibit reduced antibody recognition. However, correlation analyses of these results with the glycolipid profile of the engineered strains suggest that other factors different from GalCer contribute to sera recognition, including total ceramide levels, dihexosylceramide (DHCer), and diglycosyldiacylglycerol (DGDAG). Finally, we discuss the best candidate strains as potential GBS-free Mycoplasma chassis.

Guillain-barré syndrome (GBS) with antecedent chikungunya infection: a case report and literature review

Guillain-Barré Syndrome (GBS) is an autoimmune neuropathy. Antecedent infections have been seen to be significant triggering factors for developing GBS. Among them, arboviral infections are rapidly gaining importance as significant triggers, especially in the areas where they are endemic. Chikungunya, an arboviral infection that usually causes a self-limiting acute febrile illness can lead to GBS as one its severe complications. Herein, we describe a case of a 21-year-old female who presented with weakness in all four limbs and paresthesia. Nerve conduction study and cerebrospinal fluid (CSF) analysis showed axonal, demyelinating motor and sensory neuropathy with albuminocytological dissociation indicating Acute Motor and Sensory Axonal Neuropathy (AMSAN) variant of GBS. Serum IgM antibodies against ganglioside GM1 were detected. Anti-Chikungunya IgM antibodies were found in both serum and CSF samples. The patient was initiated with Intravenous Immunoglobulin (IVIG) therapy. In view of hypoxia, she was intubated and was on mechanical ventilation. After 2 weeks of being comatose, the patient gradually improved and was discharged with no sequelae.A literature review on antecedent infections in GBS is presented alongside the case report to better understand the association of GBS with antecedent infections, especially the endemic arboviral infections like Chikungunya, Dengue and Zika. This will help in reinforcing the significance of having robust surveillance and public health control measures for infectious diseases.

European Academy of Neurology/Peripheral Nerve Society Guideline on diagnosis and treatment of Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is an acute polyradiculoneuropathy. Symptoms may vary greatly in presentation and severity. Besides weakness and sensory disturbances, patients may have cranial nerve involvement, respiratory insufficiency, autonomic dysfunction and pain. To develop an evidence-based guideline for the diagnosis and treatment of GBS, using Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology a Task Force (TF) of the European Academy of Neurology (EAN) and the Peripheral Nerve Society (PNS) constructed 14 Population/Intervention/Comparison/Outcome questions (PICOs) covering diagnosis, treatment and prognosis of GBS, which guided the literature search. Data were extracted and summarised in GRADE Summaries of Findings (for treatment PICOs) or Evidence Tables (for diagnostic and prognostic PICOs). Statements were prepared according to GRADE Evidence-to-Decision (EtD) frameworks. For the six intervention PICOs, evidence-based recommendations are made. For other PICOs, good practice points (GPPs) are formulated. For diagnosis, the principal GPPs are: GBS is more likely if there is a history of recent diarrhoea or respiratory infection; CSF examination is valuable, particularly when the diagnosis is less certain; electrodiagnostic testing is advised to support the diagnosis; testing for anti-ganglioside antibodies is of limited clinical value in most patients with typical motor-sensory GBS, but anti-GQ1b antibody testing should be considered when Miller Fisher syndrome (MFS) is suspected; nodal-paranodal antibodies should be tested when autoimmune nodopathy is suspected; MRI or ultrasound imaging should be considered in atypical cases; and changing the diagnosis to acute-onset chronic inflammatory demyelinating polyradiculoneuropathy (A-CIDP) should be considered if progression continues after 8 weeks from onset, which occurs in around 5% of patients initially diagnosed with GBS. For treatment, the TF recommends intravenous immunoglobulin (IVIg) 0.4 g/kg for 5 days, in patients within 2 weeks (GPP also within 2-4 weeks) after onset of weakness if unable to walk unaided, or a course of plasma exchange (PE) 12-15 L in four to five exchanges over 1-2 weeks, in patients within 4 weeks after onset of weakness if unable to walk unaided. The TF recommends against a second IVIg course in GBS patients with a poor prognosis; recommends against using oral corticosteroids, and weakly recommends against using IV corticosteroids; does not recommend PE followed immediately by IVIg; weakly recommends gabapentinoids, tricyclic antidepressants or carbamazepine for treatment of pain; does not recommend a specific treatment for fatigue. To estimate the prognosis of individual patients, the TF advises using the modified Erasmus GBS outcome score (mEGOS) to assess outcome, and the modified Erasmus GBS Respiratory Insufficiency Score (mEGRIS) to assess the risk of requiring artificial ventilation. Based on the PICOs, available literature and additional discussions, we provide flow charts to assist making clinical decisions on diagnosis, treatment and the need for intensive care unit admission.

European Academy of Neurology/Peripheral Nerve Society Guideline on diagnosis and treatment of Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is an acute polyradiculoneuropathy. Symptoms may vary greatly in presentation and severity. Besides weakness and sensory disturbances, patients may have cranial nerve involvement, respiratory insufficiency, autonomic dysfunction and pain. To develop an evidence-based guideline for the diagnosis and treatment of GBS, using Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology, a Task Force (TF) of the European Academy of Neurology (EAN) and the Peripheral Nerve Society (PNS) constructed 14 Population/Intervention/Comparison/Outcome questions (PICOs) covering diagnosis, treatment and prognosis of GBS, which guided the literature search. Data were extracted and summarised in GRADE Summaries of Findings (for treatment PICOs) or Evidence Tables (for diagnostic and prognostic PICOs). Statements were prepared according to GRADE Evidence-to-Decision (EtD) frameworks. For the six intervention PICOs, evidence-based recommendations are made. For other PICOs, good practice points (GPPs) are formulated. For diagnosis, the principal GPPs are: GBS is more likely if there is a history of recent diarrhoea or respiratory infection; CSF examination is valuable, particularly when the diagnosis is less certain; electrodiagnostic testing is advised to support the diagnosis; testing for anti-ganglioside antibodies is of limited clinical value in most patients with typical motor-sensory GBS, but anti-GQ1b antibody testing should be considered when Miller Fisher syndrome (MFS) is suspected; nodal-paranodal antibodies should be tested when autoimmune nodopathy is suspected; MRI or ultrasound imaging should be considered in atypical cases; and changing the diagnosis to acute-onset chronic inflammatory demyelinating polyradiculoneuropathy (A-CIDP) should be considered if progression continues after 8 weeks from onset, which occurs in around 5% of patients initially diagnosed with GBS. For treatment, the TF recommends intravenous immunoglobulin (IVIg) 0.4 g/kg for 5 days, in patients within 2 weeks (GPP also within 2-4 weeks) after onset of weakness if unable to walk unaided, or a course of plasma exchange (PE) 12-15 L in four to five exchanges over 1-2 weeks, in patients within 4 weeks after onset of weakness if unable to walk unaided. The TF recommends against a second IVIg course in GBS patients with a poor prognosis; recommends against using oral corticosteroids, and weakly recommends against using IV corticosteroids; does not recommend PE followed immediately by IVIg; weakly recommends gabapentinoids, tricyclic antidepressants or carbamazepine for treatment of pain; does not recommend a specific treatment for fatigue. To estimate the prognosis of individual patients, the TF advises using the modified Erasmus GBS outcome score (mEGOS) to assess outcome, and the modified Erasmus GBS Respiratory Insufficiency Score (mEGRIS) to assess the risk of requiring artificial ventilation. Based on the PICOs, available literature and additional discussions, we provide flow charts to assist making clinical decisions on diagnosis, treatment and the need for intensive care unit admission.

Ophthalmoplegia associated with anti-GQ1b antibodies: case report and review

A 60-year-old man with longstanding bilateral asymmetrical ptosis presented with a partial third nerve palsy. His diplopia improved following an ice pack test. He did not report any symptoms related to the coronavirus disease 2019 (COVID-19), and nasopharyngeal swab was negative. Initial head imaging and blood work-up were normal except for a high titer of anti-GQ1b antibodies. The patient was subsequently diagnosed with acute ophthalmoparesis without ataxia which is part of the anti-GQ1b antibody syndrome spectrum. He made a spontaneous recovery over the following months without the need for immunotherapy. Clinical features, pathophysiology and a review of the literature are discussed herein. It is important to consider anti-GQ1b antibody syndrome in patients with symptoms of diplopia, ptosis or suspected ocular myasthenia.

Biological functions of sialic acid as a component of bacterial endotoxin

Lipopolysaccharide (endotoxin, LPS) is an important Gram-negative bacteria antigen. LPS of some bacteria contains sialic acid (Neu5Ac) as a component of O-antigen (O-Ag), in this review we present an overview of bacteria in which the presence of Neu5Ac has been confirmed in their outer envelope and the possible ways that bacteria can acquire Neu5Ac. We explain the role of Neu5Ac in bacterial pathogenesis, and also involvement of Neu5Ac in bacterial evading the host innate immunity response and molecular mimicry phenomenon. We also highlight the role of sialic acid in the mechanism of bacterial resistance to action of serum complement. Despite a number of studies on involvement of Neu5Ac in bacterial pathogenesis many aspects of this phenomenon are still not understood.

Impact of antecedent infections on the antibodies against gangliosides and ganglioside complexes in guillain-barré syndrome: A correlative study

Background and Aims:

Guillain-Barré Syndrome (GBS), an immune-mediated neuropathy, is characterized by antibodies against gangliosides/ganglioside complexes (GSCs) of peripheral nerves. Antecedent infections have been reported to induce antibodies that cross-react with the host gangliosides and thereby have a pivotal role in conferring an increased risk for developing GBS. Data pertaining to the impact of various antecedent infections, particularly those prevalent in tropical countries like India on the ganglioside/GSC antibodies is sparse. We aimed at exploring the association between six antecedent infections and the profile of ganglioside/GSC antibodies in GBS.

Methods:

Patients with GBS (n = 150) and healthy controls (n = 50) were examined for the serum profile of antibodies against GM1, GM2, GD1a, GD1b, GT1b, and GQ1b and their GSCs by ELISA. These antibodies were correlated with immunoreactivities against Campylobacter jejuni, Japanese encephalitis (JE), dengue, influenza, zika, and chikungunya infections.

Results:

The frequencies of antibodies against six single gangliosides (P < 0.001) and their GSCs (P = 0.039) were significantly higher in patients as compared to controls. Except for GT1b-antibody which was more frequent in axonal GBS, none of the other ganglioside/GSC antibodies correlated with the electrophysiological subtypes of GBS. Antecedent JE infection was significantly associated with increased frequency of antibodies against GD1a, GD1b, GT1b, and GQ1b. Antibodies against GSCs were not influenced by the antecedent infections.

Interpretation:

This study for the first time shows an association between antecedent JE infection and ganglioside antibodies in GBS. This finding reinforces the determining role of antecedent infections on ganglioside antibody responses and the subsequent immunological processes in GBS.

Immune mechanisms, the role of complement, and related therapies in autoimmune neuropathies

INTRODUCTION

Autoimmune neuropathies have diverse presentations and underlying immune mechanisms. Demonstration of efficacy of therapeutic agents that inhibit the complement cascade would confirm the role of complement activation.

AREAS COVERED

A review of the pathophysiology of the autoimmune neuropathies, to identify those that are likely to be complement mediated.

EXPERT OPINION

Complement mediated mechanisms are implicated in the acute and chronic neuropathies associated with IgG or IgM antibodies that target the Myelin Associated Glycoprotein (MAG) or gangliosides in the peripheral nerves. Antibody and complement mechanisms are also suspected in the Guillain-Barré syndrome and chronic inflammatory demyelinating neuropathy, given the therapeutic response to plasmapheresis or intravenous immunoglobulins, even in the absence of an identifiable target antigen. Complement is unlikely to play a role in paraneoplastic sensory neuropathy associated with antibodies to HU/ANNA-1 given its intracellular localization. In chronic demyelinating neuropathy with anti-nodal/paranodal CNTN1, NFS-155, and CASPR1 antibodies, myotonia with anti-VGKC LGI1 or CASPR2 antibodies, or autoimmune autonomic neuropathy with anti-gAChR antibodies, the response to complement inhibitory agents would depend on the extent to which the antibodies exert their effects through complement dependent or independent mechanisms. Complement is also likely to play a role in Sjogren's, vasculitic, and cryoglobulinemic neuropathies.

Galactocerebroside biosynthesis pathways of Mycoplasma species: an antigen triggering Guillain-Barré-Stohl syndrome

Infection by Mycoplasma pneumoniae has been identified as a preceding factor of Guillain-Barré-Stohl syndrome. The Guillain-Barré-Stohl syndrome is triggered by an immune reaction against the major glycolipids and it has been postulated that M. pneumoniae infection triggers this syndrome due to bacterial production of galactocerebroside. Here, we present an extensive comparison of 224 genome sequences from 104 Mycoplasma species to characterize the genetic determinants of galactocerebroside biosynthesis. Hidden Markov models were used to analyse glycosil transferases, leading to identification of a functional protein domain, termed M2000535 that appears in about a third of the studied genomes. This domain appears to be associated with a potential UDP-glucose epimerase, which converts UDP-glucose into UDP-galactose, a main substrate for the biosynthesis of galactocerebroside. These findings clarify the pathogenic mechanisms underlining the triggering of Guillain-Barré-Stohl syndrome by M. pneumoniae infections.

Immunoglobulin Treatment in Neuromuscular Medicine

Intravenous immunoglobulin (IVIg) is used in the treatment of autoimmune diseases, including immune-mediated central and peripheral nervous system disorders. This article will review the indications, proposed mechanism of actions, and administration of immunoglobulin treatment in various neuropathies, neuromuscular junction disorders, and myopathies. IVIg may have more than one mechanism of action to alter the pathogenesis of underlying neuromuscular disease. IVIg treatment has been used as a first-line treatment in Guillain-Barre syndrome, chronic inflammatory demyelinating polyradiculoneuropathy, multifocal motor neuropathy, and second-line off-label treatment in medically refractory cases of polymyositis, dermatomyositis, and myasthenia gravis. IVIg is a well-tolerated and effective treatment for these neuromuscular diseases. With this review article, we hope to increase clinicians' awareness of the indications and efficiencies of IVIg in a broad spectrum of neuromuscular diseases.

Quantification of Campylobacter jejuni contamination on chicken carcasses in France

Highly prevalent in poultry, Campylobacter is a foodborne pathogen which remains the primary cause of enteritis in humans. Several studies have determined prevalence and contamination level of this pathogen throughout the food chain. However it is generally performed in a deterministic way without considering heterogeneity of contamination level. The purpose of this study was to quantify, using probabilistic tools, the contamination level of Campylobacter spp. on chicken carcasses after air-chilling step in several slaughterhouses in France. From a dataset (530 data) containing censored data (concentration <10CFU/g), several factors were considered, including the month of sampling, the farming method (standard vs certified) and the sampling area (neck vs leg). All probabilistic analyses were performed in R using fitdistrplus, mc2d and nada packages. The uncertainty (i.e. error) generated by the presence of censored data was small (ca 1 log₁₀) in comparison to the variability (i.e. heterogeneity) of contamination level (3 log₁₀ or more), strengthening the probabilistic analysis and facilitating result interpretation. The sampling period and sampling area (neck/leg) had a significant effect on Campylobacter contamination level. More precisely, two "seasons" were distinguished: one from January to May, another one from June to December. During the June-to-December season, the mean Campylobacter concentration was estimated to 2.6 [2.4; 2.8] log₁₀ (CFU/g) and 1.8 [1.5; 2.0] log₁₀ (CFU/g) for neck and leg, respectively. The probability of having >1000CFU/g (higher limit of European microbial criterion) was estimated to 35.3% and 12.6%, for neck and leg, respectively. In contrast, during January-to-May season, the mean contamination level was estimated to 1.0 [0.6; 1.3] log₁₀ (CFU/g) and 0.6 [0.3; 0.9] log₁₀ (CFU/g) for neck and leg, respectively. The probability of having >1000CFU/g was estimated to 13.5% and 2.0% for neck and leg, respectively. An accurate quantification of contamination level enables industrials to better adapt their processing and hygiene practices. These results will also help in refining exposure assessment models.

Association of anti-gangliosides antibodies and anti-CMV antibodies in Guillain-Barré syndrome

INTRODUCTION

Numerous types of infection were closely related to GBS, mainly including Campylobacter jejuni, Cytomegalovirus, which may lead to the production of anti-gangliosides antibodies (AGA). Currently, although there are increased studies on the AGA and a few studies of anti-CMV antibodies in GBS, the association between them remains poorly documented. Therefore, our research aims to analyze the correlation of anti-CMV antibodies and AGA in GBS.

METHODS

A total of 29 patients with GBS were enrolled in this study. The CMV antibodies were tested by the electrochemiluminescence immunoassay "ECLIA" (Roche Diagnostics GmbH). The serum gangliosides were determined by The EUROLINE test kit.

RESULTS

Of the 29 patients with GBS, 9 (31%) were AGA-seropositive, in which 22 were CMV-IgG positive in CSF at the same time, but all 29 samples were CMV-IgM negative in both serum and CSF. In the AGA-positive group, the rate of both serum and CSF positive was 87.5% (7/8), higher than 50% (7/14) of the negative group, although no statistical significance was found. In addition, we found that there was a trend of higher ratio of men, a younger age onset, less frequent preceding infection, a higher level of CSF proteins, and less frequent cranial nerve deficits, although the data did not reach a statistical significance.

CONCLUSION

In spite of no statistical significance association was found between serum AGA and CMV-IgG in serum and CSF. However, we found that there was a trend of high positive rate of both serum and CSF-CMV-IgG in AGA-positive than the negative group. So we should further expand the sample size to analyze the association between AGA and CMV or other neurotropic virus antibodies in various diseases, to observe whether they could be serological marker of these diseases (especially GBS) or the underlying pathogenesis.

Mycoplasma pneumoniae triggering the Guillain-Barré syndrome: A case-control study

OBJECTIVE

Guillain-Barré syndrome (GBS) is an acute postinfectious immune-mediated polyneuropathy. Although preceding respiratory tract infections with Mycoplasma pneumoniae have been reported in some cases, the role of M. pneumoniae in the pathogenesis of GBS remains unclear. We here cultured, for the first time, M. pneumoniae from a GBS patient with antibodies against galactocerebroside (GalC), which cross-reacted with the isolate. This case prompted us to unravel the role of M. pneumoniae in GBS in a case-control study.

METHODS

We included 189 adults and 24 children with GBS and compared them to control cohorts for analysis of serum antibodies against M. pneumoniae (n = 479) and GalC (n = 198).

RESULTS

Anti-M. pneumoniae immunoglobulin (Ig) M antibodies were detected in GBS patients and healthy controls in 3% and 0% of adults (p = 0.16) and 21% and 7% of children (p = 0.03), respectively. Anti-GalC antibodies (IgM and/or IgG) were found in 4% of adults and 25% of children with GBS (p = 0.001). Anti-GalC-positive patients showed more-frequent preceding respiratory symptoms, cranial nerve involvement, and a better outcome. Anti-GalC antibodies correlated with anti-M. pneumoniae antibodies (p < 0.001) and cross-reacted with different M. pneumoniae strains. Anti-GalC IgM antibodies were not only found in GBS patients with M. pneumoniae infection, but also in patients without neurological disease (8% vs 9%; p = 0.87), whereas anti-GalC IgG was exclusively found in patients with GBS (9% vs 0%; p = 0.006).

INTERPRETATION

M. pneumoniae infection is associated with GBS, more frequently in children than adults, and elicits anti-GalC antibodies, of which specifically anti-GalC IgG may contribute to the pathogenesis of GBS. Ann Neurol 2016;80:566-580.

Seroprevalence of campylobacteriosis and relevant post-infectious sequelae

Post-infectious sequelea such as Guillain Barré syndrome (GBS), reactive arthritis (RA), and inflammatory bowel disease (IBD) may arise as a consequence of acute Campylobacter-enteritis (AE). However, reliable seroprevalence data of Campylobacter-associated sequelae has not been established. The objectives of this study were, first, to identify the most specific and sensitive test antigen in an optimized ELISA assay for diagnosing a previous Campylobacter-infection and, second, to compare the prevalence of anti-Campylobacter antibodies in cohorts of healthy blood donors (BD), AE, GBS, RA, and IBD patients with antibodies against known GBS, RA and IBD triggering pathogens. Optimized ELISAs of single and combined Campylobacter-proteins OMP18 and P39 as antigens were prepared and sera from AE, GBS, RA and IBD patients and BD were tested for Campylobcter-specific IgA and IgG antibodies. The results were compared with MIKROGEN™-recomLine Campylobacter IgA/IgG and whole cell lysate-immunoblot. Antibodies specific for Helicobacter pylori, Mycoplasma pneumoniae, Yersinia enterocolitica, and Borrelia afzelii were tested with commercial immunoblots. ROC plot analysis revealed AUC maxima in the combination of OMP18 and P39 for IgA and in the P39-antigen for IgG. As a result, 34–49 % GBS cases, 44–62 % RA cases and 23–40 % IBD cases were associated with Campylobacter-infection. These data show that Campylobcater-seropositivity in these patient groups is significantly higher than other triggering pathogens suggesting that it plays an important role in development of GBS and RA, and supports the hypothesis that recurrent acute campylobacteriosis triggers IBD.

Clinical features in Guillain-Barré syndrome with anti-Gal-C antibody

INTRODUCTION

Guillain-Barré syndrome (GBS) has often been associated with antibodies to glycolipids, such as galactocerebroside (Gal-C), a component of myelin. Whether patients who have GBS with anti-Gal-C antibody (Gal-C-GBS) more often have demyelinating neuropathy or axonal neuropathy remains controversial. Their clinical features have also been unestablished.

METHODS

We enrolled 47 patients with Gal-C-GBS. Their clinical and electrophysiological data were retrospectively reviewed and compared to 119 patients with GBS without anti-Gal-C antibody (non-Gal-C-GBS).

RESULTS

Demyelinating polyneuropathy occurred 4 times more frequently than axonal polyneuropathy in patients with Gal-C-GBS, but without statistical significance compared to patients with non-Gal-C-GBS (2.2:1). Patients with Gal-C-GBS had more frequent sensory deficits, autonomic involvements, and antecedent Mycoplasma pneumoniae (MP) infection than patients with non-Gal-C-GBS.

CONCLUSIONS

This is the largest study clarifying the clinical and electrophysiological findings that more frequent sensory deficits, autonomic involvements, and antecedent MP infection are associated with Gal-C-GBS.

Identification of gene networks and pathways associated with Guillain-Barré syndrome

BACKGROUND

The underlying change of gene network expression of Guillain-Barré syndrome (GBS) remains elusive. We sought to identify GBS-associated gene networks and signaling pathways by analyzing the transcriptional profile of leukocytes in the patients with GBS.

METHODS AND FINDINGS

Quantitative global gene expression microarray analysis of peripheral blood leukocytes was performed on 7 patients with GBS and 7 healthy controls. Gene expression profiles were compared between patients and controls after standardization. The set of genes that significantly correlated with GBS was further analyzed by Ingenuity Pathways Analyses. 256 genes and 18 gene networks were significantly associated with GBS (fold change ≥2, P<0.05). FOS, PTGS2, HMGB2 and MMP9 are the top four of 246 significantly up-regulated genes. The most significant disease and altered biological function genes associated with GBS were those involved in inflammatory response, infectious disease, and respiratory disease. Cell death, cellular development and cellular movement were the top significant molecular and cellular functions involved in GBS. Hematological system development and function, immune cell trafficking and organismal survival were the most significant GBS-associated function in physiological development and system category. Several hub genes, such as MMP9, PTGS2 and CREB1 were identified in the associated gene networks. Canonical pathway analysis showed that GnRH, corticotrophin-releasing hormone and ERK/MAPK signaling were the most significant pathways in the up-regulated gene set in GBS.

CONCLUSIONS

This study reveals the gene networks and canonical pathways associated with GBS. These data provide not only networks between the genes for understanding the pathogenic properties of GBS but also map significant pathways for the future development of novel therapeutic strategies.

Clinical characteristics of Guillain-Barré syndrome in a tropical country: a Brazilian experience

OBJECTIVE

To analyze the clinical variants, outcomes, and prognosis of Guillain-Barré syndrome (GBS) in a Brazilian population.

MATERIALS AND METHODS

Clinical and laboratory data of 149 cases of GBS diagnosed from 1994 to 2007 were analyzed.

RESULTS

Acute inflammatory demyelinating polyneuropathy (AIDP) was the most frequent variant (81.8%) of GBS, followed by acute motor axonal neuropathy (AMAN) (14.7%) and acute motor and sensory axonal neuropathy (AMSAN) (3.3%). The incidence of GBS was 0.3/100,000 for the state of Rio Grande do Norte and cases occurred at a younger age. GBS was preceded by infections, with the axonal variant associated with episodes of diarrheas (P = 0.025). Proximal weakness was more frequent in AIDP, and distal weakness predominant in the axonal variant. Compared to 42.4% of cases with AIDP (P < 0.0001), 84.6% of cases with the axonal variant had nadir in <10 days. Individuals with the axonal variant took longer to recover deambulation (P < 0.0001). The mortality of GBS was 5.3%.

CONCLUSION

A predominance of the AIDP variant was seen, and the incidence of the disease decreased with age. As expected, the distribution of weakness correlated with the clinical variants, and individuals with the axonal variant had a poorer prognosis.

Guillain-Barre syndrome, influenzalike illnesses, and influenza vaccination during seasons with and without circulating A/H1N1 viruses

The role of influenzalike illnesses and influenza vaccination in the development of Guillain-Barré syndrome (GBS), particularly the role of A/H1N1 epidemics and A/H1N1 vaccination, is debated. Data on all incident GBS cases meeting the Brighton Collaboration criteria that were diagnosed at 25 neurology centers in France were prospectively collected between March 2007 and June 2010, covering 3 influenzavirus seasons, including the 2009-2010 A/H1N1 outbreak. A total of 457 general practitioners provided a registry of patients from which 1,080 controls were matched by age, gender, index date (calendar month), and region to 145 cases. Causal relations were assessed by multivariate case-control analysis with adjustment for risk factors (personal and family history of autoimmune disorders, among others), while matching on age, gender, and calendar time. Influenza (seasonal or A/H1N1) or influenzalike symptoms in the 2 months preceding the index date was associated with GBS, with a matched odds ratio of 2.3 (95% confidence interval (CI): 0.7, 8.2). The difference in the rates of GBS occurring between influenza virus circulation periods and noncirculation periods was highly statistically significant (P = 0.004). Adjusted odds ratios for GBS occurrence within 6 weeks after seasonal and A/H1N1 vaccination were 1.3 (95% CI: 0.4, 4.1) and 0.9 (95% CI: 0.1, 7.6), respectively. Study results confirm that influenza virus is a likely risk factor for GBS. Conversely, no new concerns have arisen regarding influenza vaccination.

Preceding infections and anti-ganglioside antibody profiles assessed by a dot immunoassay in 306 French Guillain-Barré syndrome patients

We describe by an in-house dot immunoassay, specific anti-ganglioside and sulfatide antibodies, by comparing the results from a large group of 134 infected French GBS patients and those from 172 noninfected French GBS and 142 control groups. A recent infection was identified in 134/306 (43.8%) GBS patients: Campylobacter jejuni (24.6%) was the most common agent, followed by cytomegalovirus (12.4%), Mycoplasma pneumoniae (3.2%) and Epstein-Barr virus (1.3%). Anti-ganglioside antibodies were detected in 97/306 (31.7%) of total GBS patients, 82/134 (61.2%) of GBS patients with a recent identified infection and 15/172 (8.7%) of the patients without identified infection. According to the specificities and antibody classes, four specific IgG antibody profiles were individualised against the two major GM1 and GD1a gangliosides in motor axonal C. jejuni-associated GBS variants, against GQ1b and disialylated gangliosides in Miller Fisher syndrome and its variants. One specific IgM profile against GM2 was found in 16/38 (42%) of severe sensory demyelinating CMV-associated GBS and in 8/17 (47%) of subjects with recent CMV infection with no neurological disease. IgG or IgM antibodies to GM1 were found in 5/10 M. pneumoniae-infected patients. IgM antibodies to GM1 were observed in the control groups, 15% of the 74 patients with amyotrophic lateral sclerosis, 19% of the 51 patients with chronic inflammatory demyelinating polyneuropathy, and 9% of the 21 healthy control subjects. The fine specificity of the four IgG antibody profiles and the IgM anti-GM2 profile is closely related to the nature of the preceding infections and the pattern of clinical features.

Acute isolated ophthalmoplegia with anti-GQ1b antibodies

Ophthalmoplegia without ataxia, areflexia or both has been designated as atypical Miller Fisher syndrome (MFS) or acute ophthalmoplegia (AO). This entity, first reported by Chiba et al. is associated with anti-GQ1b IgG antibodies.We report a patient with isolated acute ophthalmoplegia with high titer of anti-GQ1b IgG antibody activity in the acute phase in whom treatment with intravenous immunoglobulin (IVIg) led to the clinical recovery and the decrease in antibody titer.

A role for interferon-beta in Guillain-Barré Syndrome?

Guillain-Barré syndrome (GBS) is an acute inflammatory demyelinating neuropathy that is associated with long-lasting morbidity and a substantial risk of mortality. The 2 reference treatments, plasma exchange and intravenous immunoglobulins (IVIg), do not change the functional prognosis for the most severely ill patients. The pathogenesis of GBS involves humoral and cellular immune dysfunctions that have only recently been characterised. Antibodies to nerve antigens may participate in complement activation, antibody-dependent macrophage cytotoxicity and reversible conduction failure. The cellular immune reaction is associated with increases in pro-inflammatory cytokines [such as tumour necrosis factor-alpha (TNFalpha)] and matrix metalloproteinases (MMPs; e.g. MMP-9), and a decrease in anti-inflammatory cytokines [such as transforming growth factor-beta1 (TGFbeta1)]. All the changes favour adhesion to and transmigration across the endothelium of immune cells, a key phenomenon associated with GBS. Recovery from GBS is characterised by the normalisation of these changes. Experimental allergic neuritis (EAN), the experimental model of GBS, has strikingly similar immunological characteristics. The usual treatment options for patients with GBS (plasma exchange and IVIg) mainly target the humoral component of the immune response. Interferon-beta (IFNbeta) is a cellular immunomodulator that inhibits antigen presentation and TNFalpha production and binding, and modulates macrophage properties. IFNbeta increases anti-inflammatory T cell functions and the production of anti-inflammatory cytokines, such as TGFbeta1. IFNbeta has important effects on leukodiapedesis, caused by modulating the expression of cell adhesion molecules and the MMP-9 proteinases. It has been used with success in EAN, in some patients with acute exacerbation of chronic inflammatory demyelinating polyneuropathy, and in 1 patient with GBS. The pathophysiology of patients with GBS, an understanding of IFNbeta properties and results of experimental studies support the investigation of IFNbeta in trials of patients with GBS.

Innate and adaptive autoimmunity directed to the central nervous system

The immune system has two major components, an innate arm and an adaptive arm. Certain autoimmune diseases of the brain represent examples of disorders where one of these constituents plays a major role. Some rare autoimmune diseases involve activation of the innate arm and include chronic infantile neurologic, cutaneous, articular (CINCA) syndrome. In contrast, adaptive immunity is prominent in multiple sclerosis, neuromyelitis optica, and the paraneoplastic syndromes where highly specific T cell responses and antibodies mediate these diseases. Studies of autoimmune brain disorders have aided in the elucidation of distinct neuronal roles played by key molecules already well known to immunologists (e.g., complement and components of the major histocompatibility complex). In parallel, molecules known to neurobiology and sensory physiology, including toll-like receptors, gamma amino butyric acid and the lens protein alpha B crystallin, have intriguing and distinct functions in the immune system, where they modulate autoimmunity directed to the brain.

Immunity to Campylobacter: its role in risk assessment and epidemiology

Acquired immunity is an important factor in the epidemiology of campylobacteriosis in the developing world, apparently limiting symptomatic infection to children of less than two years. However, also in developed countries the highest incidence is observed in children under five years and the majority of Campylobacter infections are asymptomatic, which may be related to the effects of immunity and/or the ingested doses. Not accounting for immunity in epidemiological studies may lead to biased results due to the misclassification of Campylobacter-exposed but apparently healthy persons as unexposed. In risk assessment studies, health risks may be overestimated when immunity is neglected.

Association of Campylobacter jejuni infection with childhood Guillain-Barré syndrome: a case-control study

A prospective case-control study was conducted to determine the association between Campylobacter jejuni infection and childhood Guillain-Barré syndrome in the Indian population. We found evidence of recent Campylobacter jejuni infection in 27.7% of patients with Guillain-Barré syndrome, as compared with 2.3% in neurological controls (P = .003) and 2.3% in nonneurological controls (P = .003). Of the 15 patients with Campylobacter jejuni infection, 8 (53.3%) reported having had diarrhea within 12 weeks before the onset of the neurologic illness. Our results suggest association between recent Campylobacter jejuni infection and bulbar weakness (P = .043). No statistical difference was observed between the Campylobacter jejuni positive and negative groups with respect to age, other clinical features, albuminocytological dissociation, and residual paralysis at follow-up. It is concluded that subclinical Campylobacter jejuni infection is an important antecedent illness in childhood Guillain-Barré syndrome in the Indian population.

Influenza, Campylobacter and Mycoplasma infections, and hospital admissions for Guillain-Barré syndrome, England

TOC Summary line: Campylobacter, Mycoplasma pneumoniae, and influenza (or influenza vaccination) act as infectious triggers for Guillain-Barré syndrome.

Guillain-Barré syndrome (GBS) is the most common cause of acute flaccid paralysis in polio-free regions. Considerable evidence links Campylobacter infection with GBS, but evidence that implicates other pathogens as triggers remains scarce. We conducted a time-series analysis to investigate short-term correlations between weekly laboratory-confirmed reports of putative triggering pathogens and weekly hospitalizations for GBS in England from 1993 through 2002. We found a positive association between the numbers of reports of laboratory-confirmed influenza A in any given week and GBS hospitalizations in the same week. Different pathogens may trigger GBS in persons of different ages; among those <35 years, numbers of weekly GBS hospitalizations were associated with weekly Campylobacter and Mycoplasma pneumoniae reports, whereas among those >35 years, positive associations were with influenza. Further studies should estimate the relative contribution of different pathogens to GBS incidence, overall and by age group, and determine whether influenza is a real trigger for GBS or a marker for influenza vaccination.

Guillain-Barré syndrome and preceding infection with campylobacter, influenza and Epstein-Barr virus in the general practice research database

Background

A number of infectious agents have previously been suggested as risk factors for the development of Guillain-Barré syndrome (GBS), but robust epidemiologic evidence for these associations is lacking.

Methods and Findings

We conducted a nested case-control study using data from the United Kingdom General Practice Research Database between 1991 and 2001. Controls were matched to cases on general practice clinic, sex, year of birth and date of outcome diagnosis in their matched case. We found positive associations between GBS and infection with Campylobacter, Epstein-Barr virus and influenza-like illness in the previous two months, as well as evidence of a protective effect of influenza vaccination. After correction for under-ascertainment of Campylobacter infection, the excess risk of GBS following Campylobacter enteritis was 60-fold and 20% of GBS cases were attributable to this pathogen.

Conclusions

Our findings indicate a far greater excess risk of GBS among Campylobacter enteritis patients than previously reported by retrospective serological studies. In addition, they confirm previously suggested associations between infection due to Epstein-Barr virus infection and influenza-like illness and GBS. Finally, we report evidence of a protective effect of influenza vaccination on GBS risk, which may be mediated through protection against influenza disease, or result from a lower likelihood of vaccination among those with recent infection. Cohort studies of GBS incidence in this population would help to clarify the burden of GBS due to influenza, and any potential protective effect of influenza vaccination.

Cytomegalovirus-Associated Periodontitis and Guillain-Barré Syndrome

BACKGROUND

Guillain-Barré syndrome (GBS), an autoimmune disorder of the peripheral nervous system, is characterized by rapidly ascending neural paralysis, hyporeflexia, and areflexia. The polyneuropathy of the GBS affects one to four humans per 100,000 of the population annually throughout the world (adults and children). The pathogenesis of GBS remains unclear. However, there are increasing indications that the disease is triggered by a preceding well-established febrile infection by cytomegalovirus (CMV). The present report describes active CMV within the periodontium of a 37-year-old patient affected by GBS.

METHODS

Real-time reverse transcriptase-polymerase chain reaction (real-time RT-PCR) was performed to detect CMV, Epstein-Barr virus-1 (EBV-1), herpes simplex 1 (HSV-1) and 2 (HSV-2) virus, and enteroviruses (polio-, coxsackie-, echo-, and enteroviruses 68 and 71) from periodontal sites demonstrating advanced attachment loss. Healthy sites and sites with inflamed gingival tissue were not included in the study. Anaerobic bacterial culture determined the occurrence of potential major periodontal pathogens.

RESULTS

Real-time RT-PCR and microbiologic analysis revealed the presence of a dual infection of CMV and specific bacterial plaque. CMV, Porphyromonas gingivalis, Tannerella forsythensis, and Campylobacter species were associated with periodontitis active sites, loss of attachment, and gingival bleeding. Furthermore, periodontal sites infected by active CMV had no visible radiographic crestal lamina dura.

CONCLUSIONS

The periodontium may serve as a reservoir for CMV and a source of viral replication. However, further research is needed to test whether viral replication in the periodontium precedes the GBS symptoms.

Guillain-Barré syndrome

Guillain-Barré syndrome consists of at least four subtypes of acute peripheral neuropathy. Major advances have been made in understanding the mechanisms of some of the subtypes. The histological appearance of the acute inflammatory demyelinating polyradiculoneuropathy (AIDP) subtype resembles experimental autoimmune neuritis, which is predominantly caused by T cells directed against peptides from the myelin proteins P0, P2, and PMP22. The role of T-cell-mediated immunity in AIDP remains unclear and there is evidence for the involvement of antibodies and complement. Strong evidence now exists that axonal subtypes of Guillain-Barré syndrome, acute motor axonal neuropathy (AMAN), and acute motor and sensory axonal neuropathy (AMSAN), are caused by antibodies to gangliosides on the axolemma that target macrophages to invade the axon at the node of Ranvier. About a quarter of patients with Guillain-Barré syndrome have had a recent Campylobacter jejuni infection, and axonal forms of the disease are especially common in these people. The lipo-oligosaccharide from the C jejuni bacterial wall contains ganglioside-like structures and its injection into rabbits induces a neuropathy that resembles acute motor axonal neuropathy. Antibodies to GM1, GM1b, GD1a, and GalNac-GD1a are in particular implicated in acute motor axonal neuropathy and, with the exception of GalNacGD1a, in acute motor and sensory axonal neuropathy. The Fisher's syndrome subtype is especially associated with antibodies to GQ1b, and similar cross-reactivity with ganglioside structures in the wall of C jejuni has been discovered. Anti-GQ1b antibodies have been shown to damage the motor nerve terminal in vitro by a complement-mediated mechanism. Results of international randomised trials have shown equivalent efficacy of both plasma exchange and intravenous immunoglobulin, but not corticosteroids, in hastening recovery from Guillain-Barré syndrome. Further research is needed to discover treatments to prevent 20% of patients from being left with persistent and significant disability.

Immunoadsorption therapy for a child with Guillain-Barre syndrome subsequent to Mycoplasma infection: a case study

We report an 11-year-old boy with apparently the motor axonal form of Guillain-Barre syndrome (GBS) who presented with severe paralysis and respiratory insufficiency by the 3rd day from onsets of symptoms. His serum anti-Mycoplasma pneumoniae and anti-Galactocerebroside (Gal-C) IgM antibody were significantly elevated. Magnetic resonance imaging, following contrast injection, showed enhancement of the cauda equina. The patient responded quickly and dramatically to immunoadsorption therapy using a tryptophan-immobilized column, with recovery of respiratory failure and muscle strength, dominantly in the left extremities. Immunoadsorption therapy should be considered for patients with anti Gal-C antibody-associated GBS.

Diagnosis and management of acute myelopathies

BACKGROUND

Acute myelopathies represent a heterogeneous group of disorders with distinct etiologies, clinical and radiologic features, and prognoses. Transverse myelitis (TM) is a prototype member of this group in which an immune-mediated process causes neural injury to the spinal cord, resulting in varying degrees of weakness, sensory alterations, and autonomic dysfunction. TM may exist as part of a multifocal CNS disease (eg, MS), multisystemic disease (eg, systemic lupus erythematosus), or as an isolated, idiopathic entity.

REVIEW SUMMARY

In this article, we summarize recent classification and diagnostic schemes, which provide a framework for the diagnosis and management of patients with acute myelopathy. Additionally, we review the state of current knowledge about the epidemiology, natural history, immunopathogenesis, and treatment strategies for patients with TM.

CONCLUSIONS

Our understanding of the classification, diagnosis, pathogenesis, and treatment of TM has recently begun to expand dramatically. With more rigorous criteria applied to distinguish acute myelopathies and with an emerging understanding of immunopathogenic events that underlie TM, it may now be possible to effectively initiate treatments in many of these disorders. Through the investigation of TM, we are also gaining a broader appreciation of the mechanisms that lead to autoimmune neurologic diseases in general.

Epidemiology of Campylobacter jejuni isolated from patients with Guillain-Barré and Fisher syndromes in Japan

Campylobacter jejuni isolation is the standard for the diagnosis of this type of bacterial infection, but there have been no epidemiological studies of a large number of C. jejuni isolates from patients with Guillain-Barre syndrome (GBS) and Fisher syndrome (FS). For 13 years, stool specimens from GBS/FS patients have been sent from 378 hospitals throughout Japan to the Tokyo Metropolitan Institute of Public Health. A total of 113 strains (11%) were isolated from the stool specimens from 1,049 patients. The isolation rate did not differ by region. The rates were 22% for 449 patients with a history of diarrhea and 2% for the others. An additional 18 isolates were provided by various hospitals. There was no noticeable seasonal distribution in the onset of C. jejuni isolated from patients with GBS/FS. The male/female ratios were 1.7:1 for GBS and 2.2:1 for FS. The patient age range showed a peak in 10- to 30-year-old subjects who had GBS and in 10- to 20-year-old subjects who had FS. The predominance of young adults and male patients who had C. jejuni-associated GBS/FS may be related to the preponderance of young adults and male patients who had C. jejuni enteritis. The median interval from diarrhea onset to neurologic symptom onset was 10 days for GBS/FS. Penner's C. jejuni serotype HS:19 was more frequently present in GBS (67%) than in enteritis (6%) patients. HS:2 was more frequent in FS (41%) than in enteritis (14%) patients. These findings suggest that certain C. jejuni strains specifically trigger GBS and that others specifically trigger FS.

Neural autoantibodies and neurophysiologic abnormalities in patients exposed to molds in water-damaged buildings

Adverse health effects of fungal bioaerosols on occupants of water-damaged homes and other buildings have been reported. Recently, it has been suggested that mold exposure causes neurological injury. The authors investigated neurological antibodies and neurophysiological abnormalities in patients exposed to molds at home who developed symptoms of peripheral neuropathy (i.e., numbness, tingling, tremors, and muscle weakness in the extremities). Serum samples were collected and analyzed with the enzyme-linked immunosorbent assay (ELISA) technique for antibodies to myelin basic protein, myelin-associated glycoprotein, ganglioside GM1, sulfatide, myelin oligodendrocyte glycoprotein, alpha-B-crystallin, chondroitin sulfate, tubulin, and neurofilament. Antibodies to molds and mycotoxins were also determined with ELISA, as reported previously. Neurophysiologic evaluations for latency, amplitude, and velocity were performed on 4 motor nerves (median, ulnar, peroneal, and tibial), and for latency and amplitude on 3 sensory nerves (median, ulnar, and sural). Patients with documented, measured exposure to molds had elevated titers of antibodies (immunoglobulin [Ig]A, IgM, and IgG) to neural-specific antigens. Nerve conduction studies revealed 4 patient groupings: (1) mixed sensory-motor polyneuropathy (n = 55, abnormal), (2) motor neuropathy (n = 17, abnormal), (3) sensory neuropathy (n = 27, abnormal), and (4) those with symptoms but no neurophysiological abnormalities (n = 20, normal controls). All groups showed significantly increased autoantibody titers for all isotypes (IgA, IgM, and IgG) of antibodies to neural antigens when compared with 500 healthy controls. Groups 1 through 3 also exhibited abnormal neurophysiologic findings. The authors concluded that exposure to molds in water-damaged buildings increased the risk for development of neural autoantibodies, peripheral neuropathy, and neurophysiologic abnormalities in exposed individuals.

Association of anti-GM1 antibodies but not of anti-cytomegalovirus, Campylobacter jejuni and Helicobacter pylori IgG, with a poor outcome in Guillain-Barré syndrome

Few reports exist on the influence of humoral immune responses, against microorganisms involved in infections preceding Guillain-Barré syndrome (GBS) and GM1, on clinical outcome. Nor is there any data on the relation between anti-Helicobacter pylori antibodies and prognosis in patients with GBS. To address these questions, we assayed and correlated serum anti-GM1 IgG and IgM and anti-H. pylori, anti-Campylobacter jejuni and anti-cytomegalovirus (CMV) IgG with duration of hospitalization of GBS patients and prognosis at discharge. Patients with anti-GM1 alone or associated with anti-H. pylori antibodies had significant longer hospitalization to reach a low clinical score at discharge than those without (P=0.004). A significant difference was also found for the association of anti-GM1 with anti-CMV antibodies (P=0.019). A weak but significant association of anti-GM1 and anti-C. jejuni antibodies with long hospitalization and worse prognosis at discharge was also found (P=0.02). The statistical significance increased when patients with anti-GM1 and anti-microorganism antibodies were compared with those displaying anti-H. pylori or anti-CMV only. These findings provide further evidence that the level of circulating anti-GM1 IgG plays a role in determining recovery from disability in GBS patients irrespective of other IgG against microorganisms causing infections preceding GBS.

Localization of major gangliosides in the PNS: implications for immune neuropathies

Antibodies targeting major gangliosides that are broadly distributed in the nervous system are sometimes associated with clinical symptoms that imply selective nerve damage. For example, anti-GD1a antibodies are associated with acute motor axonal neuropathy (AMAN), a form of Guillain-Barré syndrome that selectively affects motor nerves, despite reports that GD1a is present in human axons and myelin and is not expressed differentially in motor versus sensory roots. We used a series of high-affinity monoclonal antibodies (mAbs) against the major nervous system gangliosides GM1, GD1a, GD1b and GT1b to test whether any of them bind motor or sensory fibres differentially in rodent and human peripheral nerves. The following observations were made. (i) Some of the anti-GD1a antibodies preferentially stained motor fibres, supporting the association of human anti-GD1a antibodies with predominant motor neuropathies such as AMAN. (ii) A GD1b antibody preferentially stained the large dorsal root ganglion (DRG) neurones, in keeping with the proposed role of human anti-GD1b antibodies in sensory ataxic neuropathies. (iii) Two mAbs with broad structural cross-reactivity bound to both gangliosides and peripheral nerve proteins. (iv) Myelin was poorly stained; all clones stained axons nearly exclusively. Our findings suggest that anti-ganglioside antibody fine specificity as well as differences in ganglioside accessibility in axons and myelin influence the selectivity of injury to different fibre systems and cell types in human autoimmune neuropathies.

Cross-reactive anti-galactocerebroside antibodies and Mycoplasma pneumoniae infections in Guillain-Barré syndrome

Anti-galactocerebroside (GalC) antibodies are reported to be present in GBS patients with preceding Mycoplasma pneumoniae (MP) infection. We investigated the presence of anti-GalC reactivity in serum of a large group of GBS patients using ELISA and compared this with healthy controls and individuals with an uncomplicated MP infection. Anti-GalC antibody reactivity was present in 12% of the GBS patients. Furthermore, anti-GalC antibodies were associated with MP infections, a relatively mild form of the disease and demyelinating features. Anti-GalC antibodies cross-reacted with MP antigen. In conclusion, anti-GalC antibodies in GBS patients may be induced by molecular mimicry with MP.

Immunopathogenesis of acute transverse myelitis

Acute transverse myelitis is a group of disorders characterized by focal inflammation of the spinal cord and resultant neural injury. Acute transverse myelitis may be an isolated entity or may occur in the context of multifocal or even multisystemic disease. It is clear that the pathological substrate--injury and dysfunction of neural cells within the spinal cord--may be caused by a variety of immunological mechanisms. For example, in acute transverse myelitis associated with systemic disease (i.e. systemic lupus erythematosus or sarcoidosis), a vasculitic or granulomatous process can often be identified. In idiopathic acute transverse myelitis, there is an intraparenchymal or perivascular cellular influx into the spinal cord, resulting in the breakdown of the blood-brain barrier and variable demyelination and neuronal injury. There are several critical questions that must be answered before we truly understand acute transverse myelitis: (1) What are the various triggers for the inflammatory process that induces neural injury in the spinal cord? (2) What are the cellular and humoral factors that induce this neural injury? and (3) Is there a way to modulate the inflammatory response in order to improve patient outcome? Although much remains to be elucidated about the causes of acute transverse myelitis, tantalizing clues as to the potential immunopathogenic mechanisms in acute transverse myelitis and related inflammatory disorders of the spinal cord have recently emerged. It is the purpose of this review to illustrate recent discoveries that shed light on this topic, relying when necessary on data from related diseases such as acute disseminated encephalomyelitis, Guillain-Barré syndrome and neuromyelitis optica. Developing a further understanding of how the immune system induces neural injury will depend upon confirmation and extension of these findings and will require multicenter collaborative efforts.

Sialosyl-galactose: a common denominator of Guillain-Barré and related disorders?

The immune reactivity implicated in the pathogenesis of Guillain-Barré syndrome (GBS) and related diseases, which occur following infection with specific strains of Campylobacter jejuni bearing sialylated lipopolysaccharide structures that cross-react with specific gangliosides, is consistent with provocation of inflammation via molecular mimicry. In this review, we have focused upon microbial characteristics and structures, the fine structure of the essential carbohydrate determinants, and the application of our proposed criteria, modified from those of Koch for causation of infectious and of Witebsky for autoimmune diseases, to the circumstance of infectious induction of autoimmune disorder.

Antibodies against gangliosides: a link between preceding infection and immunopathogenesis of Guillain-Barré syndrome

Autoantibodies against gangliosides GM1 and GQ1b, characteristic cell surface glycolipids of the nervous system, are present in specific clinical types of GuillainBarré syndrome (GBS). Close associations of anti-GM1 with acute motor axonal neuropathy, and of anti-GQ1b with Miller Fisher syndrome, strongly suggest that these antibodies contribute to neuropathy pathogenesis. Immune responses against gangliosides are suspected to originate as a result of molecular mimicry between gangliosides and lipopolysaccharides of Campylobacter jejuni, the most frequent infectious trigger of GBS. Thus, antibodies against gangliosides may link C. jejuni infection with the precipitation of neurological disease.

Differential immune response to gangliosides in Guillain-Barré syndrome patients from Japan and The Netherlands

Anti-ganglioside antibodies are consistently found in Guillain-Barré syndrome (GBS) patients from different geographical parts of the world. Several studies indicated differences in relative frequencies of anti-ganglioside reactivity and isotype distribution between GBS patients from Asia and from Europe. We investigated antibody reactivity against the gangliosides GM1, GM1b and GalNAc-GD1a in GBS patients from Japan and The Netherlands in two different laboratories. The proportion of GBS patients with anti-ganglioside antibodies did not differ between the two countries. GBS patients from The Netherlands more frequently had cross-reacting anti-GalNAc-GD1a/anti-GM1b antibodies and a stronger IgM anti-ganglioside response. Our findings indicate that geographical determined factors, dependent on either the host or the triggering infectious agent, determine the isotype distribution and fine specificity of anti-ganglioside antibodies in GBS patients.

Intravenous immunoglobulin for cranial polyneuropathy associated with Campylobacter jejuni infection

This study reports the efficacy of i.v. immunoglobulin in a patient with cranial polyneuropathy resulting from Campylobacter jejuni infection who had high titers of serum IgG antibodies against gangliosides GD1a and GT1b in the acute phase. Treatment with i.v. immunoglobulin (400 mg/kg/day x 5 days) led to rapid partial resolution of his neurologic manifestations, but complete recovery was not obtained until 6 months later. The present case suggests that i.v. immunoglobulin therapy prevents further progression of the disease but that it may not shorten the clinical course of cranial polyneuropathy in some cases associated with Campylobacter jejuni infection.

Multicenter evaluation of the novel enzyme immunoassay based on P1-enriched protein for the detection of Mycoplasma pneumoniae infection

The aim of the study was to evaluate new Mycoplasma pneumoniae IgG, IgA and IgM EIA methods based on the enrichment of P1-protein (ThermoLabsystems, Helsinki, Finland) (L) for the detection of acute infection. This evaluation was performed in two independent routine clinical microbiology laboratories. The first laboratory used samples preselected by IgG and IgM Platelia enzyme immunoassay (P) and the second used samples preseleced by Serion ELISA Classic M. pneumoniae IgG, IgM (V). The L method was also compared to the FDA approved method of ImmunoWell M. pneumoniae IgG and IgM (G). When the agreement of two methods was applied as a serologic criteria for an acute infection, the following ratios of acute to nonacute infection were calculated 32/86 (totally 118) in the first and 20/72 (totally 92) in the second laboratory. In the first laboratory, the corresponding ratios by methods were 35/83 (sensitivity 100%, specificity 96.5%), 31/87 (sensitivity 97%, specificity 100%), and 55/63 (sensitivity 100%, specificity 79%) for the L, P and G methods, respectively. In the second laboratory, the ratios were 21/71 (sensitivity 100%, specificity 99%), 16/76 (sensitivity 83%, specificity 100%), and 53/39 (sensitivity 100, specificity 69%) for the L, V and G methods, respectively. Taking into account that the tested sample material was preselected by the P and V methods, which may have introduced some bias in their favor, the newly developed L method utilizing P1-enriched protein was found reliable for serodiagnosis of acute M. pneumoniae infection. The method G was the least specific in detection of acute infection.

Three patients with ophthalmoplegia associated with Campylobacter jejuni

Cranial polyneuropathy is idiopathic in most patients. Idiopathic cranial polyneuropathy is an acute postinfectious syndrome, along with Guillain-Barré syndrome and Miller Fisher syndrome, in which the common preceding pathogen is Campylobacter jejuni. Serum anti-GQ1b antibodies are elevated in Miller Fisher syndrome and Guillain-Barré syndrome with ophthalmoplegia. Three patients with idiopathic cranial polyneuropathy with predominant ocular involvement are presented. C. jejuni isolated from stool specimens belonged to Penner serotypes O:4, O:23, and O:33. Serum anti-GQ1b antibodies were elevated in all patients but demonstrated rapid reduction concomitant with clinical recovery. All patients recovered completely. Because both preceding C. jejuni infection and elevated anti-GQ1b antibodies decreasing with time were seen in all patients, the pathogenesis of idiopathic cranial polyneuropathy with ophthalmoplegia may be similar to that of Miller Fisher syndrome.

Molecular mimicry in Campylobacter jejuni and Helicobacter pylori lipopolysaccharides: contribution of gastrointestinal infections to autoimmunity

Molecular mimicry of host structures by the saccharide portion of lipopolysaccharides (LPS) of the gastrointestinal pathogens Campylobacter jejuni and Helicobacter pylori is thought to be associated with the development of autoimmune sequelae. C. jejuni, a leading cause of gastroenteritis, is the most common antecedent infection in Guillain-Barré syndrome (GBS), an inflammatory neuropathy. Chemical analyses of the core oligosaccharides of neuropathy-associated C. jejuni strains have revealed structural homology with human gangliosides. Serum antibodies against gangliosides are found in one third of GBS patients but are generally absent in enteritis cases. Collective data suggest that the antibodies are induced by antecedent infection with C. jejuni, and subsequently react with nerve tissue causing damage. The O-chains of most H. pylori strains express Lewis blood group antigens which are thought to have a role in camouflage of the bacterium as these antigens are also present on human gastric epithelial cells. In chronic H. pylori infections, bacterial expression of Lewis antigens is suggested to be involved in the induction of autoantibodies against the Lewis antigen-expressing gastric proton pump. Many aspects of the autoimmune mechanisms in C. jejuni -associated GBS and H. pylori -induced atrophic gastritis remain unclear, such as the involvement of T cells and the role of host factors.

Antecedent symptoms in Guillain-Barré syndrome: an important indicator for clinical and serological subgroups

OBJECTIVES

To examine whether Guillain-Barré syndrome (GBS) can be classified in clinical and immunological subgroups based on the type of prior illness. Background - The existence of antecedent symptoms supports the diagnosis of GBS in patients who experience acute muscle weakness progression. However, little is known about additional meanings of determining antecedent symptoms.

MATERIALS AND METHODS

Prospective investigation of prior infectious illness in GBS and related disorders (n=176).

RESULTS

The frequent antecedent symptoms in GBS and related disorders were fever (52%), cough (48%), sore throat (39%), nasal discharge (30%), and diarrhea (27%). Patients who had sore throats or coughs frequently had ophthalmoparesis (respectively P=0.0004, P=0.001) and IgG anti-GQ1b antibody (P=0.01, P=0.007). Fever was associated with bulbar palsy (P=0.047) and headache with facial palsy (P=0.04). Patients with diarrhea often had anti-ganglioside IgG (anti-GM1 [P=0.0006] and anti-GM1b [P=0.008]), IgM (anti-GM1 [P=0.03], anti-GM1b [P=0.02], and anti-GalNAc-GD1a [P=0.047]) antibodies and rarely showed ophthalmoparesis or bulbar palsy (respectively P=0.02, P=0.04). Diarrhea and abdominal pain were closely associated with Campylobacter jejuni serology (respectively P<0.0001, P=0.01), whereas other symptoms were not related to pathogens such as cytomegalovirus, Epstein-Barr virus, or Mycoplasma pneumoniae.

CONCLUSIONS

Our comprehensive study showed that GBS preceded by sore throat, cough, fever, headache, or diarrhea respectively forms clinical or serological subgroups, or both. This association is not necessarily dependent on infection by the known trigger pathogens.

Guillain-Barré syndrome- and Miller Fisher syndrome-associated Campylobacter jejuni lipopolysaccharides induce anti-GM1 and anti-GQ1b Antibodies in rabbits

Campylobacter jejuni infections are thought to induce antiganglioside antibodies in patients with Guillain-Barré syndrome (GBS) and Miller Fisher syndrome (MFS) by molecular mimicry between C. jejuni lipopolysaccharides (LPS) and gangliosides. We used purified LPS fractions from five Campylobacter strains to induce antiganglioside responses in rabbits. The animals that received injections with LPS from GBS-associated strains developed anti-GM1 and anti-GA1 antibodies. Animals injected with LPS from one MFS-related C. jejuni strain produced anti-GQ1b antibodies. Rabbits that were injected with Penner O:3 LPS had a strong anti-LPS response, but no antiganglioside reactivity was observed. The antiganglioside specificity in the rabbits reflected the specificity in the patients from whom the strains were isolated. In conclusion, our results indicate that an immune response against GBS- and MFS-associated C. jejuni LPS results in antiganglioside antibodies. These results provide strong support for molecular mimicry as a mechanism in the induction of antiganglioside antibodies following infections.

Campylobacter Enteritis and the Guillain-Barré Syndrome

Campylobacter jejuni is one of the most common causes of bacterial gastroenteritis in the United States and worldwide with approximately 2.4 million infections per year in the United States. A now clearly recognized sequelae following Campylobacter infection is the Guillain-Barré syndrome, an acute immune-mediated attack on the peripheral nervous system. How Campylobacter induces Guillain-Barré syndrome is the subject of intense investigation, and this article discusses some of the recent advances in our understanding of the clinical, epidemiologic, and pathogenic features of the disease.