Preceding infections and anti-ganglioside antibodies in patients with Guillain-Barré syndrome: a single centre prospective case-control study

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated encephalitis induced by Mycoplasma pneumoniae infections

BACKGROUND

This study aims to report the phenomenon of Myelin oligodendrocyte glycoprotein antibody-associated encephalitis induced by Mycoplasma pneumoniae infections and promote the potential benefits of combining early immunotherapy and anti-M-pneumoniae therapy for these patients.

METHODS

Three children with MOG-IgG-associated encephalitis due to M. pneumoniae infections who were treated at our hospital from September to November 2023 were included in the study. We investigated and analyzed the background and clinical features of these patients.

RESULTS

Three patients developed headaches, seizures, and/or other neurological manifestations, elevated mononuclear cells in cerebrospinal fluid, intracranial lesions on cranial magnetic resonance imaging (MRI), and positive MOG-IgG in serum, within 10-14 days. They were diagnosed with MOG-IgG-associated encephalitis due to M. pneumoniae infections, the treatment consisted of intravenous immunoglobulin, glucocorticoid, and erythromycin, then they were completely recovered.

CONCLUSION

Mycoplasma pneumoniae (M. pneumoniae) infections can cause oligodendrocyte glycoprotein (MOG) antibody-associated encephalitis. The recognition of this condition will promote the potential benefits of combining early immunotherapy and anti-M. pneumoniae therapy for patients with MOG-IgG-associated encephalitis.

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.

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.

Campylobacter jejuni Infection, Anti-Ganglioside Antibodies, and Neuropathy

Preceding infection with Campylobacter jejuni (Cj) occurs in approximately 30% of patients with Guillain–Barre syndrome (GBS), and the risk of GBS following Cj infection is increased by 77 to 100-fold. GBS is most often of the axonal subtype and is thought to be mediated by IgG antibodies to peripheral nerve gangliosides that are cross reactive with oligosaccharides in the Cj lipopolysaccharides (LPS). The antibodies are thought to be induced by molecular mimicry, where immune reactivity to a cross reactive epitope in the infectious organism and normal tissue can cause autoimmune disease. Clonally restricted IgM antibodies that react with the same oligosaccharides in gangliosides and Cj-LPS are associated with chronic neuropathies of otherwise similar phenotypes. The anti-ganglioside antibodies in GBS are of the IgG1 and IgG3 subclasses, indicating T-cell reactivity to the same antigens that could help disrupt the blood–nerve barrier. Cj infection can activate multiple innate and adoptive pro-inflammatory pathways that can overcome immune tolerance and induce autoimmunity. Elucidation of the specific immune mechanisms involved in the development of the autoantibodies and neuropathy would help our understanding of the relation between infection and autoimmunity and aid in the development of more effective preventive interventions and therapies.

Guillain-Barré Syndrome with Lethal Outcome Following COVID-19 Vaccination - Case Report Supported by Autopsy Examination

Objective:

After the outbreak of the global pandemic caused by SARS-CoV-2 infection at the end of the year 2019, it took one year to start vaccination against this infection with products from various manufacturers. As of November 2021, more than 8 billion vaccine doses against COVID-19 have been administered, which is essentially linked to a spike in adverse events reports following these vaccinations, including a number of neurological adverse events.

Case Report:

We report a case of a 71-year-old patient with lethal fulminant onset of Guillain-Barré syndrome after the second dose of mRNA vaccine tozinameran. This is, to our best knowledge, the first case report of this adverse event supported by autopsy and histological examination. The patient presented with progressive ascending weakness and paresthesia, with typical cytoalbuminologic dissociation in cerebrospinal fluid and severe motoric and sensitive axonal-demyelinating polyneuropathy on electromyography. The patient’s history and complex diagnostic workup did not reveal any other possible causative factors. The patient did not respond to the treatment with intravenous immunoglobulins and died 10 days later due to aspiration bronchopneumonia as a complication of respiratory muscles paralysis.

Conclusion:

Most of the reported adverse reactions following COVID-19 vaccination include mild or moderate events noticed in the post-vaccination period; however, reports of possible lethal outcomes are no exception. Still, the overall incidence of GBS after vaccination does not significantly exceed its incidence in the general population. Each such report should be carefully examined by a team of specialists to prevent overestimation of lethal adverse events linked to vaccinations, especially in fatalities that happen in the post-vaccination period.

Pragmatic guide to peripheral nerve disease and the role of clinical biomarkers

In clinical neurology practice, there are few sensitive, specific and responsive serological biomarkers reflecting pathological processes affecting the peripheral nervous system. Instead, we rely on surrogate multimodality biomarkers for diagnosis and management. Correct use and interpretation of the available tests is essential to ensure that appropriate treatments are used and adjusted in a timely fashion. The incorrect application or interpretation of biomarkers can result in misdiagnosis and delays in appropriate treatment. Here, we discuss the uses and limitations of such biomarkers and discuss possible future developments.

Outcomes of patients presenting with Guillain-Barre Syndrome at a tertiary care center in India

Background

The Guillain-Barre Syndrome (GBS), also known as acute idiopathic polyneuritis, is a critical acquired condition associated with preceding nonspecific infection or triggering factors like trauma, surgery, or vaccination. GBS is currently the most frequent cause of acute flaccid paralysis in India. This study evaluates the short-term and in-hospital outcomes in different subtypes of GBS.

Methods

A prospective observational study was conducted at V.S. Hospital, Ahmedabad, from September 2015 to December 2017. Patients above the age of 12 were included. Patients having other underlying neurological conditions, as well as immunodeficiency disorders, were excluded. The patients were classified into different subtypes of GBS, and functional outcomes were recorded on admission and discharge according to Hughes Scoring System. All statistical analyses were performed by using SPSS software.

Results

Out of 50 patients, 35 (70%) were males. The mean age was of 37.18 +/− 18.35 years. 25 (50%) patients had a preceding infection. 88% of patients presented with cranial nerve (CN) involvement had a Hughes Score of >/= 3 (p = 0.0087). They had less improvement of Hughes Score on discharge (0.13 +/− 0.04) as compared to the patients without cranial nerve involvement (0.38 +/− 0.08) (p = 0.008). Respiratory involvement was associated with a higher Hughes Score (p = 0.005) on admission. 85% of patients diagnosed with an axonal subtype of GBS had a Hughes Score of >/= 3 (p = 0.06) compared to 74% patients with demyelinating subtype. Axonal subtype required double period (11 +/− 2.34) to show improvement as compared to demyelinating subtype (6 +/− 1.2) (p = 0.020). Irrespective of the subtypes, in two different treatment cohorts (PLEX vs IVIG), there was no difference in short term functional outcomes measured by improvement in the Hughes scores (p = 0.89).

Conclusions

Early cranial nerve and respiratory involvement in patients presenting with GBS are associated with poor outcomes warranting immediate critical care involvement. In our study, amongst all the subtypes, axonal had poor clinical outcomes. Further clinical trials on the Indian subpopulation will help us evaluate the impact of different treatment modalities on this disease.

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.

Acute Polyradiculomyelitis With Spinal Cord Gray Matter Lesions: A Report of Two Cases

Objective: Inflammatory polyradiculomyelitis belongs to a rare group of immune-mediated diseases affecting both the central and peripheral nervous system. We aimed to describe an unusual presentation of acute polyradiculomyelitis with marked spinal cord lesions restricted to the gray matter.

Methods: Thorough examination of two case reports including clinical, MRI, serologic, electrophysiologic and CSF examinations as well as short-term follow-up.

Results: We present two adult patients with acute polyradiculomyelitis and unusual spinal cord lesions restricted to the gray matter on MRI. The clinical presentation, serologic, electrophysiologic and CSF features of the two patients varied, whereas both patients demonstrated severe, asymmetrical, predominantly distal, motor deficits of the lower extremities as well as bladder and bowel dysfunction. Both patients only partially responded to anti-inflammatory treatment. Severe motor impairment and bladder dysfunction persisted even months after symptom onset.

Conclusions: To our best of knowledge, these are the first reports of acute polyradiculomyelitis with distinct involvement of the lower thoracic spinal cord gray matter. Currently, it remains unclear whether gray matter lesions reflect a separate pathophysiologic mechanism or an exceedingly rare presentation of spinal cord involvement in acute polyradiculomyelitis.

Antecedent infections in Guillain-Barré syndrome patients from south India

Guillain-Barré syndrome (GBS) is the commonest post-infectious inflammatory peripheral neuropathy with undiscerned aetiology. The commonly reported antecedent infections implicated in India include Campylobacter jejuni, chikungunya, dengue, and Japanese encephalitis (JE). In this study from south India, we investigated the role of these four agents in triggering GBS. This case-control study was performed on 150 treatment-naive patients with GBS and 150 age and sex-matched controls from the same community. IgM immunoreactivity for C. jejuni, chikungunya, and dengue was detected by enzyme-linked immunosorbent assay (ELISA) in serum of patients with GBS and control subjects. Immunoreactivity against JE was detected in serum as well as cerebrospinal fluid (CSF) from patients (n = 150) and orthopaedic control (n = 45) subjects. The immunoreactivity against infections was compared between demyelinating and axonal subtypes of GBS. Overall, 119/150 patients with GBS had serological evidence of antecedent infection. Amongst those with evidence of antecedent infection, 24 (16%), 8 (5%), and 9 (6%) patients were exclusively immunoreactive to chikungunya, JE, and C. jejuni, respectively. In the remaining patients (78/119), immunoreactivity to multiple pathogens was noted. Immunoreactivity to C. jejuni infection was found in 32% of GBS patients compared to 2.7% controls (P < .001), whereas to chikungunya virus was reported in 66.7% of patients with GBS compared to 44.7% controls (P = .006). Anti-dengue immunoreactivity was significantly associated with the demyelinating subtype of GBS. Patients positive for JE IgM (CSF) manifested demyelinating electrophysiology. In this large case-control study, immunoreactivity against multiple infectious agents was observed in a subset of patients. Chikungunya was the commonest antecedent infection, followed by C. jejuni.

Association of Hospital-Diagnosed Infections and Antibiotic Use With Risk of Developing Guillain-Barré Syndrome

OBJECTIVE

To determine whether hospital-diagnosed and community-treated infections are important Guillain-Barré syndrome (GBS) risk factors, we investigated the magnitude and duration of associated GBS risk.

METHODS

We conducted a nationwide population-based case-control study of all patients with first-time hospital-diagnosed GBS in Denmark between 1987 and 2016 and 10 matched population controls per case. Hospital-diagnosed infections were determined in the 1987-2016 period and community antibiotic prescriptions in the 2004-2016 period. We used conditional logistic regression to examine the relative risk of GBS associated with having a recent infection.

RESULTS

Hospital-diagnosed infections within 60 days were observed in 4.3% of 2,414 GBS cases vs 0.3% of 23,909 controls, with a matched odds ratio (OR) of 13.7 (95% confidence interval [CI], 10.2-18.5). The strongest association with subsequent GBS was observed for lower respiratory tract infection, gastrointestinal tract infection, and septicemia. Community antibiotic prescriptions within 60 days were observed in 22.4% of 1,086 GBS cases and 7.8% of 10,747 controls, with a matched OR of 3.5 (95% CI, 3.0-4.1). The risk of GBS declined considerably with time since infection, with high ORs of 21.3 (95% CI, 14.5-31.2) and 4.7 (95% CI, 3.9-5.7) observed within the first month after a hospital-diagnosed infection and a community antibiotic prescription, respectively. However, GBS risk remained increased 2.4-fold (95% CI, 1.1-5.5) and 1.5-fold (95% CI, 1.2-2.0) even in the fifth month after infection.

CONCLUSION

There is a strong, temporal association between community antibiotic use and especially infections necessitating hospitalization and risk of subsequent GBS.

Cardiovascular complications and its relationship with functional outcomes in Guillain-Barré syndrome

BACKGROUND

Guillain-Barré syndrome (GBS) is a monophasic disease characterized by acute polyradiculoneuropathy.

AIM

This study investigated cardiovascular complications in patients with GBS and their relationship with outcomes.

DESIGN AND METHODS

We included 96 patients, who were diagnosed with GBS according to Brighton case definitions. All enrolled patients were evaluated according to a predetermined algorithm, which included nerve conduction studies, cerebrospinal fluid analysis, electrocardiography, 2D echo, cardiac markers and autonomic function testing.

RESULTS

We enrolled a total of 96 patients. The mean age of patients was 35.75 ± 17.66 years. Furthermore, 54.2% of patients developed cardiovascular complications, of which changes in electrocardiography (ECG) findings (50%), hypertension (28.12%), labile hypertension (12.5), tachycardia (26.04), bradycardia (13.54%) and a fluctuating heart rate (HR) (11.46) were common. Other cardiovascular complications seen in GBS patients were increased pro-BNP (26.04%), raised troponin T levels (3.12%), acute coronary syndrome (2.08%), heart failure (2.08%) and abnormal 2D echo findings (8.33%). The results of the univariate analysis revealed that a history of preceding infection, a Medical Research Council sum score, neck muscle weakness, facial nerve involvement, bulbar involvement, respiratory failure, cardiovascular complications, autonomic dysfunction, acute motor sensory axonal neuropathy subtype and baseline Hughes score were significantly (P < 0.005) associated with poor outcomes. However, none of these factors were found to be independently associated with poor outcomes in the multivariate analysis.

CONCLUSION

A considerable number of patients with GBS developed cardiovascular complications and it needs attention.

Systematic review of factors associated with the development of Guillain-Barré syndrome 2007-2017: what has changed?

OBJECTIVE

The objective of this study was to describe the factors associated with the development of Guillain-Barré syndrome, both infectious and non-infectious, during and after the A(H1N1) influenza pandemic in 2009 and the recent Zika virus epidemic in the Americas.

METHOD

Systematic review of literature on factors associated with the development of the Guillain-Barré syndrome published between 2007 and 2017 listed in EBSCO, MEDLINE and LILACS databases. The quality of the studies was evaluated using the Newcastle Ottawa Scale.

RESULTS

Thirty-four articles met inclusion criteria and were selected for analysis. Their quality was considered good in relation to most of the items evaluated. Many aetiological agents had the results of association with Guillain-Barré syndrome, among them Campylobacter jejuni, influenza vaccine - both pandemic and seasonal vaccines, respiratory infection, gastrointestinal infection among others. The aetiological agents found are, in most part, the same reported prior to the study period. The association with surgeries, chikungunya virus (CHIKV), Zika virus and quadrivalent human papillomavirus vaccine stand out as new aetiological agents in the list of the various possible agents that trigger Guillain-Barré syndrome reported in the study period. There were no Brazilian studies identified during this period.

CONCLUSIONS

The results of the review reaffirmed C. jejuni as the major trigger of GBS, whereas the association of influenza vaccines and GBS is less clear; Zika virus infection in association with GBS was found in only one study.

Guillain-Barré syndrome following bacterial meningitis: a case report and literature review

Background

We reported a case of an adult that presented Guillain-Barré syndrome (GBS) after bacterial meningitis which was secondary to chronic suppurative otitis media (CSOM). To our knowledge, this is the first case involving an adult presenting with GBS following bacterial meningitis.

Case presentation

A 46-year man with type 2 diabetes and otitis media (OM) suffered with fever, headache, and vomiting for 6 days. The patient’s neck stiffness was obvious and the Kernig and Brudzinski signs were produced. The result of cerebrospinal fluid (CSF) analysis and cytological examination of the CSF supported the diagnose of bacterial meningitis. On day 17 the patient felt numbness in both hands and feet, which gradually progressed to weakness of the limbs. Bladder dysfunction occurred, which required catheterization. The patient showed a tetraparesis with emphasis on the legs. The deep tendon reflexes of limbs were absent. The patient had peripheral hypalgesia and deep sensory dysfunction. The symptoms were possibly a result of GBS. Nerve conduction study showed that the F wave latency of the upper and lower limbs was prolonged, particularly the lower limbs. 8 days later the repeated nerve conduction study showed a low compound muscle action potential (3.3 mV) with a normal distal motor latency (14.2 ms) and a low motor nerve conduction velocity (34.3 m/s) in the tibial nerve. The patient still required assistance when walking 3 months after onset.

Conclusions

GBS following bacterial meningitis is rare and limbs weakness in patients with bacterial meningitis was usually considered because of weakness. This case should serve as a reminder for clinical doctors that when a patient with bacterial meningitis complains about limbs numbness or weakness, GBS should be considered, especially when the patient had diabetes mellitus (DM) history.

Pathogenesis and Treatment of Neurologic Diseases Associated With Mycoplasma pneumoniae Infection

Mycoplasma pneumoniae is mainly recognized as a respiratory pathogen, although it is associated with the development of several extra-respiratory conditions in up to 25% of the cases. Diseases affecting the nervous system, both the peripheral (PNS) and the central nervous system (CNS), are the most severe. In some cases, particularly those that involve the CNS, M. pneumoniae-related neuropathies can lead to death or to persistent neurologic problems with a significant impact on health and a non-marginal reduction in the quality of life of the patients. However, the pathogenesis of most of the M. pneumoniae-related neuropathies remains undefined. The main aim of this paper is to discuss what is presently known regarding the pathogenesis and treatment of the most common neurologic disorders associated with M. pneumoniae infection. Unfortunately, the lack of knowledge of the true pathogenesis of most of the cases of M. pneumoniae-mediated neurological diseases explains why treatment is not precisely defined. However, antibiotic treatment with drugs that are active against M. pneumoniae and able to pass the blood-brain barrier is recommended, even though the best drug, dosage, and duration of therapy have not been established. Sporadic clinical reports seem to indicate that because immunity plays a relevant role in the severity of the condition and outcome, attempts to reduce the immune response can be useful. However, further studies are needed before the problem of the best therapy for M. pneumoniae-mediated neurological diseases can be efficiently solved.

Pathogenesis of Mycoplasma pneumoniae: An update

Genus Mycoplasma, belonging to the class Mollicutes, encompasses unique lifeforms comprising of a small genome of 8,00,000 base pairs and the inability to produce a cell wall under any circumstances. Mycoplasma pneumoniae is the most common pathogenic species infecting humans. It is an atypical respiratory bacteria causing community acquired pneumonia (CAP) in children and adults of all ages. Although atypical pneumonia caused by M. pneumoniae can be managed in outpatient settings, complications affecting multiple organ systems can lead to hospitalization in vulnerable population. M. pneumoniae infection has also been associated with chronic lung disease and bronchial asthma. With the advent of molecular methods of diagnosis and genetic, immunological and ultrastructural assays that study infectious disease pathogenesis at subcellular level, newer virulence factors of M. pneumoniae have been recognized by researchers. Structure of the attachment organelle of the organism, that mediates the crucial initial step of cytadherence to respiratory tract epithelium through complex interaction between different adhesins and accessory adhesion proteins, has been decoded. Several subsequent virulence mechanisms like intracellular localization, direct cytotoxicity and activation of the inflammatory cascade through toll-like receptors (TLRs) leading to inflammatory cytokine mediated tissue injury, have also been demonstrated to play an essential role in pathogenesis. The most significant update in the knowledge of pathogenesis has been the discovery of Community-Acquired Respiratory Distress Syndrome toxin (CARDS toxin) of M. pneumoniae and its ability of adenosine diphosphate (ADP) ribosylation and inflammosome activation, thus initiating airway inflammation. Advances have also been made in terms of the different pathways behind the genesis of extrapulmonary complications. This article aims to comprehensively review the recent advances in the knowledge of pathogenesis of this organism, that had remained elusive during the era of serological diagnosis. Elucidation of virulence mechanisms of M. pneumoniae will help researchers to design effective vaccine candidates and newer therapeutic targets against this agent.

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.

Severe childhood Guillain-Barré syndrome associated with Mycoplasma pneumoniae infection: a case series

We report seven children with recent Mycoplasma pneumoniae infection and severe Guillain-Barré syndrome (GBS) that presented to two European medical centres from 1992 to 2012. Severe GBS was defined as the occurrence of respiratory failure, central nervous system (CNS) involvement, or death. Five children had GBS, one Bickerstaff brain stem encephalitis (BBE), and one acute-onset chronic inflammatory demyelinating polyneuropathy (A-CIDP). The five patients with severe GBS were derived from an original cohort of 66 children with GBS. In this cohort, 17 children (26%) had a severe form of GBS and 47% of patients with M. pneumoniae infection presented with severe GBS. Of the seven patients in this case series, five were mechanically ventilated and four had CNS involvement (two were comatose). Most patients presented with non-specific clinical symptoms (nuchal rigidity and ataxia) and showed a rapidly progressive disease course (71%). Antibodies against M. pneumoniae were detected in all patients and were found to be intrathecally synthesised in two cases (GBS and BBE), which proves intrathecal infection. One patient died and only two patients recovered completely. These cases illustrate that M. pneumoniae infection in children can be followed by severe and complicated forms of GBS. Non-specific clinical features of GBS in such patients may predispose a potentially life-threatening delay in diagnosis.

Infection with and Carriage of Mycoplasma pneumoniae in Children

“Atypical” pneumonia was described as a distinct and mild form of community-acquired pneumonia (CAP) already before Mycoplasma pneumoniae had been discovered and recognized as its cause. M. pneumoniae is detected in CAP patients most frequently among school-aged children from 5 to 15 years of age, with a decline after adolescence and tapering off in adulthood. Detection rates by polymerase chain reaction (PCR) or serology in children with CAP admitted to the hospital amount 4–39%. Although the infection is generally mild and self-limiting, patients of every age can develop severe or extrapulmonary disease. Recent studies indicate that high rates of healthy children carry M. pneumoniae in the upper respiratory tract and that current diagnostic PCR or serology cannot discriminate between M. pneumoniae infection and carriage. Further, symptoms and radiologic features are not specific for M. pneumoniae infection. Thus, patients may be unnecessarily treated with antimicrobials against M. pneumoniae. Macrolides are the first-line antibiotics for this entity in children younger than 8 years of age. Overall macrolides are extensively used worldwide, and this has led to the emergence of macrolide-resistant M. pneumoniae, which may be associated with severe clinical features and more extrapulmonary complications. This review focuses on the characteristics of M. pneumoniae infections in children, and exemplifies that simple clinical decision rules may help identifying children at high risk for CAP due to M. pneumoniae. This may aid physicians in prescribing appropriate first-line antibiotics, since current diagnostic tests for M. pneumoniae infection are not reliably predictive.

[Neurological symptoms due to Mycoplasma pneumoniae infection in nine children]

Mycoplasma pneumoniae infection is common in children. Extrapulmonary symptoms usually reveal as neurological symptoms, mainly as encephalitis with significant morbidity and mortality. Various other neurological presentations have also been reported. We describe a cohort of nine children with neurological manifestations due to M. pneumoniae infection, including five cases of encephalitis, one of polyradiculoneuritis, one of ophthalmoplegia, one of optic neuritis, and one of myositis. Progression was variable from ad integrum recovery to severe brain damage. Diagnosis is usually confirmed by PCR and/or serological follow-up, but the latter is still insufficiently used in practice to systematically affirm the diagnosis. Therapeutic management is not clearly defined and long-term progression can be uncertain despite early antibiotic and/or anti-inflammatory treatments.

Guillain-Barré syndrome: subtypes and predictors of outcome from India

There is a paucity of large studies evaluating the subtypes of Guillain-Barré syndrome (GBS) and their outcome from Southeast Asia. We report cliniconeurophysiological subtypes of GBS and their correlation with triggering events and 3-month outcome from northern India. Three hundred and twenty eight consecutive patients with GBS were clinically evaluated, including their triggers, severity, autonomic involvement, cranial nerve palsy, and respiratory paralysis. Nerve conduction study (NCS) was repeated at 3 weeks if the initial study was normal. They were categorized into acute inflammatory demyelinating polyradiculoneuropathy (AIDP), acute motor axonal neuropathy (AMAN), acute motor sensory axonal neuropathy (AMSAN), inexcitable motor nerve, and equivocal. Clinically, 204 (62.2%) patients had pure motor, 106 (32.3%) motor sensory, 16 (4.9%) Miller Fisher syndrome, and 2 (0.6%) pure sensory GBS. Based on NCS, 242 (73.8%) had AIDP, 44 (13.4%) AMAN, 15 (4.6%) AMSAN, 8 (2.4%) inexcitable motor nerves, and 27 (8.2%) equivocal GBS. AIDP patients were older, more common in summer, had lesser peak disability, and better outcome compared to those with AMAN. Eleven (3.4%) patients died and 48 (14.6%) had poor outcome at 3 months. The poor outcome was related to severity, dysautonomia, and inexcitable motor nerves. AIDP is the commonest variant of GBS in our study and has better outcome compared to AMAN.

Acute small fiber neuropathy following Mycoplasma infection: a rare variant of Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is a well-described condition involving the peripheral nervous system. The most well-known form of this disease is acute inflammatory demyelinating polyradiculoneuropathy. Among the different variants of GBS described in the literature, the sensory variant is scantily recognized. There has been a recent attempt to classify the sensory variants of the GBS and bring more objectivity to this diagnostic paradigm. We report a rare sensory variant of GBS presenting with isolated small nerve fiber involvement peripherally in the limbs and associated facial nerve palsy in a patient who had clinical and serological evidence of a preceding Mycoplasma pneumoniae infection. The symptoms resolved gradually with intravenous immunoglobulin therapy. This case adds to the growing literature of the rare form of acute small fiber neuropathy and GBS variants.

Infectious and noninfectious triggers in Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is the commonest cause of acquired flaccid paralysis in the world and regarded by many as the prototype for postinfectious autoimmunity. Here the authors consider both infectious and noninfectious triggers of GBS and determine where possible what immunological mechanisms may account for this association. In approximately two-thirds of cases, an infectious trigger is reported in the weeks that lead up to disease onset, indicating that the host's response to infection must play an important role in disease pathogenesis. The most frequently identified bacteria, Campylobacter jejuni, through a process known as molecular mimicry, has been shown to induce cross-reactive anti-ganglioside antibodies, which can lead to the development of axonal-type GBS in some patients. Whether this paradigm can be extended to other infectious organisms or vaccines remains an important area of research and has public health implications. GBS has also been reported rarely in patients with underlying systemic diseases and immunocompromised states and although the exact mechanism is yet to be established, increased susceptibility to known infectious triggers should be considered most likely.

Role of Campylobacter jejuni infection in the pathogenesis of Guillain-Barré syndrome: an update

Our current knowledge on Campylobacter jejuni infections in humans has progressively increased over the past few decades. Infection with C. jejuni is the most common cause of bacterial gastroenteritis, sometimes surpassing other infections due to Salmonella, Shigella, and Escherichia coli. Most infections are acquired due to consumption of raw or undercooked poultry, unpasteurized milk, and contaminated water. After developing the diagnostic methods to detect C. jejuni, the possibility to identify the association of its infection with new diseases has been increased. After the successful isolation of C. jejuni, reports have been published citing the occurrence of GBS following C. jejuni infection. Thus, C. jejuni is now considered as a major triggering agent of GBS. Molecular mimicry between sialylated lipooligosaccharide structures on the cell envelope of these bacteria and ganglioside epitopes on the human nerves that generates cross-reactive immune response results in autoimmune-driven nerve damage. Though C. jejuni is associated with several pathologic forms of GBS, axonal subtypes following C. jejuni infection may be more severe. Ample amount of existing data covers a large spectrum of GBS; however, the studies on C. jejuni-associated GBS are still inconclusive. Therefore, this review provides an update on the C. jejuni infections engaged in the pathogenesis of GBS.

Immunoglobulin IgG Fc-receptor polymorphisms and HLA class II molecules in Guillain-Barré syndrome

OBJECTIVE

To analyze host genetic factors immunoglobulin G Fc receptors (FcgammaRs) and human leukocyte antigen (HLA) class II in GBS patients.

METHODS

FcgammaRIIA, IIIA and IIIB polymorphisms were studied in 80 each GBS patients and healthy controls by allele specific PCR. HLA class II DRbeta1 and DQbeta1 typing was performed at the two-digit level by PCR in randomly selected 54 GBS patients and 202 controls.

RESULTS

FcgammaRIIA-H/H (56% vs 9%; P < 0.0001) and FcgammaRIIIA-V/V (40% vs 13%; P < 0.0001) genotypes, H131 allele frequencies (0.73 vs 0.26, P < 0.0001) and HLA DQbeta1*060x (OR, 1.96; 95% CI, 1.26-3.04; P < 0.01) were significantly increased in GBS than controls. DRbeta1*0701 alone (OR, 10; 95% CI, 45.90-2.25; P < 0.001) and together with FcgammaRIIA-H/H (OR, 11.03; 95% CI, 2.63-46.20; P < 0.001) was significantly associated with GBS patients having microbiological evidence of recent infection.

CONCLUSIONS

The study indicates that homozygous FcgammaRIIA and FcgammaRIIIA genotypes and FcgammaRIIA H131 allele are associated with GBS. HLA class II molecule DRbeta1*0701 is identified as novel genetic risk factor for development of GBS in patients with preceding infection.

Pathogenesis of neurologic manifestations of Mycoplasma pneumoniae infection

Mycoplasma pneumoniae has been associated with various neurologic manifestations, but exactly how the organism can cause such a wide variety of diseases is a long-standing mystery. In this respect, although pneumonia has been considered the hallmark of Mycoplasma pneumoniae infection, emerging accumulations of data have revealed that the infection can cause a number of extrapulmonary manifestations even in the absence of pneumonia. The importance of host immune response in the pathomechanism of pneumonia has been established, but the pathomechanisms of extrapulmonary manifestations remain largely unknown. For this review, extrapulmonary manifestations due to M. pneumoniae infection were classified into three categories: a direct type, in which locally induced cytokines must play a role; an indirect type, in which immune modulation such as autoimmunity must play a role; and a vascular occlusion type, in which vasculitis or thrombosis (either or both, and with or without systemic hypercoagulable state) must play a role. This classification was then applied within a literature review for neurologic manifestations. Most neurologic manifestations due to M. pneumoniae infection could be reasonably classified into and explained by one of the three types of pathomechanisms.

Correlation between genotypic diversity, lipooligosaccharide gene locus class variation, and caco-2 cell invasion potential of Campylobacter jejuni isolates from chicken meat and humans: contribution to virulotyping

Significant interest in studying the lipooligosaccharide (LOS) of Campylobacter jejuni has stemmed from its potential role in postinfection paralytic disorders. In this study we present the results of PCR screening of five LOS locus classes (A, B, C, D, and E) for a collection of 116 C. jejuni isolates from chicken meat (n = 76) and sporadic human cases of diarrhea (n = 40). We correlated LOS classes with clonal complexes (CC) assigned by multilocus sequence typing (MLST). Finally, we evaluated the invasion potential of a panel of 52 of these C. jejuni isolates for Caco-2 cells. PCR screening showed that 87.1% (101/116) of isolates could be assigned to LOS class A, B, C, D, or E. Concordance between LOS classes and certain MLST CC was revealed. The majority (85.7% [24/28]) of C. jejuni isolates grouped in CC-21 were shown to express LOS locus class C. The invasion potential of C. jejuni isolates possessing sialylated LOS (n = 29; classes A, B, and C) for Caco-2 cells was significantly higher (P < 0.0001) than that of C. jejuni isolates with nonsialylated LOS (n = 23; classes D and E). There was no significant difference in invasiveness between chicken meat and human isolates. However, C. jejuni isolates assigned to CC-206 (correlated with LOS class B) or CC-21 (correlated with LOS class C) showed statistically significantly higher levels of invasion than isolates from other CC. Correlation between LOS classes and CC was further confirmed by pulsed-field gel electrophoresis. The present study reveals a correlation between genotypic diversity and LOS locus classes of C. jejuni. We showed that simple PCR screening for C. jejuni LOS classes could reliably predict certain MLST CC and add to the interpretation of molecular-typing results. Our study corroborates that sialylation of LOS is advantageous for C. jejuni fitness and virulence in different hosts. The modulation of cell surface carbohydrate structure could enhance the ability of C. jejuni to adapt to or survive in a host.

Influence of host interleukin-10 polymorphisms on development of traveler's diarrhea due to heat-labile enterotoxin-producing Escherichia coli in travelers from the United States who are visiting Mexico

Up to 60% of U.S. visitors to Mexico develop traveler's diarrhea (TD), mostly due to enterotoxigenic Escherichia coli (ETEC) strains that produce heat-labile (LT) and/or heat-stable (ST) enterotoxins. Distinct single-nucleotide polymorphisms (SNPs) within the interleukin-10 (IL-10) promoter have been associated with high, intermediate, or low production of IL-10. We conducted a prospective study to investigate the association of SNPs in the IL-10 promoter and the occurrence of TD in ETEC LT-exposed travelers. Sera from U.S. travelers to Mexico collected on arrival and departure were studied for ETEC LT seroconversion by using cholera toxin as the antigen. Pyrosequencing was performed to genotype IL-10 SNPs. Stools from subjects who developed diarrhea were also studied for other enteropathogens. One hundred twenty-one of 569 (21.3%) travelers seroconverted to ETEC LT, and among them 75 (62%) developed diarrhea. Symptomatic seroconversion was more commonly seen in subjects who carried a genotype producing high levels of IL-10; it was seen in 83% of subjects with the GG genotype versus 54% of subjects with the AA genotype at IL-10 gene position -1082 (P, 0.02), in 71% of those with the CC genotype versus 33% of those with the TT genotype at position -819 (P, 0.005), and in 71% of those with the CC genotype versus 38% of those with the AA genotype at position -592 (P, 0.02). Travelers with the GCC haplotype were more likely to have symptomatic seroconversion than those with the ATA haplotype (71% versus 38%; P, 0.002). Travelers genetically predisposed to produce high levels of IL-10 were more likely to experience symptomatic ETEC TD.