Outcomes of mechanical thrombectomy at a single-centre tertiary level public healthcare hospital in South Africa.

INTRODUCTION: Mechanical thrombectomy (MT) is standard of care for acute ischaemic stroke from large vessel occlusion following randomised controlled trials performed largely in high-income countries. Limited data exists on its effectiveness in the setting of low-and-middle-income countries. We aimed to evaluate the safety and efficacy of MT in a tertiary level public hospital in Cape Town, South Africa. METHODS: Patients with acute ischaemic stroke presenting consecutively to Groote Schuur Hospital between 1 January 2018 to 1 January 2022 with proximal intracranial occlusion in the anterior circulation treated with MT within 6 h from onset using computed tomography (CT) and CT angiography imaging-based protocols were evaluated. Demographic, clinical, radiological and procedural data were obtained from the stroke unit database. Recanalisation was evaluated post-procedure by modified Treatment in Cerebral Infarction score (mTICI). Functional independence (modified Rankin scores 0-2) and mortality at 90 days were also assessed. RESULTS: Thrombectomies were performed in 84 patients during the study period. The median age was 56 years (interquartile range, IQR) and 51% of participants were female. Median National Institute of Health Stroke Score was 18 and median baseline Alberta Stroke Programme Early CT score was 8. Bridging thrombolysis was given to 65% of participants. Median time from symptom onset to reperfusion was 339 min (IQR). Successful recanalisation (mTICI 2b/3) was obtained in 62%. At 90 days, 34% of participants gained functional independence and mortality was 34%. CONCLUSION: This study demonstrated similar rates of recanalisation and functional independence to that seen in trials in high-income countries using basic imaging despite a higher mortality and longer median time to reperfusion. This data supports the effectiveness of MT in a tertiary level public hospital in South Africa despite the challenges of providing emergent stroke care in a resource-constrained setting.

Primary Sjögren's syndrome with renal tubular acidosis and central pontine myelinolysis: An unusual triad.

Primary Sjögren's syndrome (pSS) is a complex, multisystem autoimmune disorder. It is characterized by lymphocytic infiltration of the exocrine glands. In the setting of pSS, the presence of systemic disease is an important prognostic determinant, but involvement of the kidney is uncommon. The triad of pSS, distal renal tubular acidosis (dRTA), and central pontine myelinolysis (CPM) is rare and potentially fatal. A 42-year-old woman presented with dRTA, profound hypokalemia, and CPM characterized by progressive global quadriparesis, ophthalmoplegia, and encephalopathy. Sjögren's syndrome was diagnosed based on sicca symptoms, clinical features, and strongly positive anti-SSA/Ro and anti-SSB/La autoantibodies. The patient responded well to electrolyte replacement, acid-base correction, corticosteroids, and subsequent cyclophosphamide therapy. Early recognition and appropriate treatment resulted in good kidney and neurological outcomes in this case. This report highlights the need to consider the diagnosis of pSS in unexplained dRTA and CPM, as it has a favorable prognosis if recognized and managed timeously.

CSF Findings in Relation to Clinical Characteristics, Subtype, and Disease Course in Patients With Guillain-Barré Syndrome.

BACKGROUND AND OBJECTIVES: To investigate CSF findings in relation to clinical and electrodiagnostic subtypes, severity, and outcome of Guillain-Barré syndrome (GBS) based on 1,500 patients in the International GBS Outcome Study. METHODS: Albuminocytologic dissociation (ACD) was defined as an increased protein level (>0.45 g/L) in the absence of elevated white cell count (<50 cells/µL). We excluded 124 (8%) patients because of other diagnoses, protocol violation, or insufficient data. The CSF was examined in 1,231 patients (89%). RESULTS: In 846 (70%) patients, CSF examination showed ACD, which increased with time from weakness onset: ≤4 days 57%, >4 days 84%. High CSF protein levels were associated with a demyelinating subtype, proximal or global muscle weakness, and a reduced likelihood of being able to run at week 2 (odds ratio [OR] 0.42, 95% CI 0.25-0.70; p = 0.001) and week 4 (OR 0.44, 95% CI 0.27-0.72; p = 0.001). Patients with the Miller Fisher syndrome, distal predominant weakness, and normal or equivocal nerve conduction studies were more likely to have lower CSF protein levels. CSF cell count was <5 cells/µL in 1,005 patients (83%), 5-49 cells/µL in 200 patients (16%), and ≥50 cells/µL in 13 patients (1%). DISCUSSION: ACD is a common finding in GBS, but normal protein levels do not exclude this diagnosis. High CSF protein level is associated with an early severe disease course and a demyelinating subtype. Elevated CSF cell count, rarely ≥50 cells/µL, is compatible with GBS after a thorough exclusion of alternative diagnoses. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that CSF ACD (defined by the Brighton Collaboration) is common in patients with GBS.

Cognitive Impairment in Tuberculous Meningitis.

BACKGROUND: Cognitive impairment is reported as a common complication in adult tuberculous meningitis (TBM), yet few studies have systematically assessed the frequency and nature of impairment. Moreover, the impact of impairment on functioning and medication adherence has not been described. METHODS: A cognitive test battery (10 measures assessing 7 cognitive domains) was administered to 34 participants with human immunodeficiency virus (HIV)-associated TBM 6 months after diagnosis. Cognitive performance was compared with that a comparator group of 66 people with HIV without a history of tuberculosis. A secondary comparison was made between participants with TBM and 26 participants with HIV 6 months after diagnosis of tuberculosis outside the central nervous system (CNS). Impact on functioning was evaluated, including through assessment of medication adherence. RESULTS: Of 34 participants with TBM, 16 (47%) had low performance on cognitive testing. Cognition was impaired across all domains. Global cognitive performance was significantly lower in participants with TBM than in people with HIV (mean T score, 41 vs 48, respectively; P < .001). These participants also had lower global cognition scores than those with non-CNS tuberculosis (mean global T score, 41 vs 46; P = .02). Functional outcomes were not significantly correlated with cognitive performance in the subgroup of participants in whom this was assessed (n = 19). CONCLUSIONS: Low cognitive performance following HIV-associated TBM is common. This effect is independent of, and additional to, effects of HIV and non-CNS tuberculosis disease. Further studies are needed to understand longer-term outcomes, clarify the association with treatment adherence, a key predictor of outcome in TBM, and develop context-specific tools to identify individuals with cognitive difficulties in order to improve outcomes in TBM.

An International Perspective on Preceding Infections in Guillain-Barré Syndrome: The IGOS-1000 Cohort.

BACKGROUND AND OBJECTIVES: Infections play a key role in the development of Guillain-Barré syndrome (GBS) and have been associated with specific clinical features and disease severity. The clinical variation of GBS across geographical regions has been suggested to be related to differences in the distribution of preceding infections, but this has not been studied on a large scale. METHODS: We analyzed the first 1,000 patients included in the International GBS Outcome Study with available biosamples (n = 768) for the presence of a recent infection with Campylobacter jejuni, hepatitis E virus, Mycoplasma pneumoniae, cytomegalovirus, and Epstein-Barr virus. RESULTS: Serologic evidence of a recent infection with C. jejuni was found in 228 (30%), M. pneumoniae in 77 (10%), hepatitis E virus in 23 (3%), cytomegalovirus in 30 (4%), and Epstein-Barr virus in 7 (1%) patients. Evidence of more than 1 recent infection was found in 49 (6%) of these patients. Symptoms of antecedent infections were reported in 556 patients (72%), and this proportion did not significantly differ between those testing positive or negative for a recent infection. The proportions of infections were similar across continents. The sensorimotor variant and the demyelinating electrophysiologic subtype were most frequent across all infection groups, although proportions were significantly higher in patients with a cytomegalovirus and significantly lower in those with a C. jejuni infection. C. jejuni-positive patients were more severely affected, indicated by a lower Medical Research Council sum score at nadir (p = 0.004) and a longer time to regain the ability to walk independently (p = 0.005). The pure motor variant and axonal electrophysiologic subtype were more frequent in Asian compared with American or European C. jejuni-positive patients (p < 0.001, resp. p = 0.001). Time to nadir was longer in the cytomegalovirus-positive patients (p = 0.004). DISCUSSION: Across geographical regions, the distribution of infections was similar, but the association between infection and clinical phenotype differed. A mismatch between symptom reporting and serologic results and the high frequency of coinfections demonstrate the importance of broad serologic testing in identifying the most likely infectious trigger. The association between infections and outcome indicates their value for future prognostic models.

Post-Infectious Autoimmunity in the Central (CNS) and Peripheral (PNS) Nervous Systems: An African Perspective.

The direct impact and sequelae of infections in children and adults result in significant morbidity and mortality especially when they involve the central (CNS) or peripheral nervous system (PNS). The historical understanding of the pathophysiology has been mostly focused on the direct impact of the various pathogens through neural tissue invasion. However, with the better understanding of neuroimmunology, there is a rapidly growing realization of the contribution of the innate and adaptive host immune responses in the pathogenesis of many CNS and PNS diseases. The balance between the protective and pathologic sequelae of immunity is fragile and can easily be tipped towards harm for the host. The matter of immune privilege and surveillance of the CNS/PNS compartments and the role of the blood-brain barrier (BBB) and blood nerve barrier (BNB) makes this even more complex. Our understanding of the pathogenesis of many post-infectious manifestations of various microbial agents remains elusive, especially in the diverse African setting. Our exploration and better understanding of the neuroimmunology of some of the infectious diseases that we encounter in the continent will go a long way into helping us to improve their management and therefore lessen the burden. Africa is diverse and uniquely poised because of the mix of the classic, well described, autoimmune disease entities and the specifically "tropical" conditions. This review explores the current understanding of some of the para- and post-infectious autoimmune manifestations of CNS and PNS diseases in the African context. We highlight the clinical presentations, diagnosis and treatment of these neurological disorders and underscore the knowledge gaps and perspectives for future research using disease models of conditions that we see in the continent, some of which are not uniquely African and, where relevant, include discussion of the proposed mechanisms underlying pathogen-induced autoimmunity. This review covers the following conditions as models and highlight those in which a relationship with COVID-19 infection has been reported: a) Acute Necrotizing Encephalopathy; b) Measles-associated encephalopathies; c) Human Immunodeficiency Virus (HIV) neuroimmune disorders, and particularly the difficulties associated with classical post-infectious autoimmune disorders such as the Guillain-Barré syndrome in the context of HIV and other infections. Finally, we describe NMDA-R encephalitis, which can be post-HSV encephalitis, summarise other antibody-mediated CNS diseases and describe myasthenia gravis as the classic antibody-mediated disease but with special features in Africa.

Varicella-zoster virus reactivation is frequently detected in HIV-infected individuals presenting with stroke.

Infections are an underappreciated cause of stroke, particularly in young and immunocompromised individuals. Varicella-zoster virus (VZV) reactivation, particularly ophthalmic zoster, has been linked to increased risk of stroke but diagnosing VZV-associated cerebral vasculopathy is challenging as neither a recent zoster rash, nor detectable levels of VZV DNA are universally present at stroke presentation. Detection of VZV IgG in cerebrospinal fluid (CSF-VZVG) presents a promising alternative, but requires evaluation of individual blood-CSF dynamics, particularly in the setting of chronic inflammatory states such as HIV infection. Consequently, its use has not been broadly adopted as simple diagnostic algorithms are not available. In this study looking at young adults presenting with acute stroke, we used an algorithm that includes testing for both VZV nucleic acids and CSF-VZVG which was corrected for blood-CSF barrier dynamics and poly-specific immune activation. We found that 13 of 35 (37%), including 7 with a positive CSF VZV PCR, young HIV-infected adults presenting with stroke, 3 of 34 (9%) young HIV-uninfected adults presenting with stroke, and 1 of 18 (6%) HIV-infected nonstroke controls demonstrated evidence of central nervous system reactivation of VZV.

Predicting Outcome in Guillain-Barré Syndrome: International Validation of the Modified Erasmus GBS Outcome Score.

BACKGROUND AND OBJECTIVES: The clinical course and outcome of the Guillain-Barré syndrome (GBS) are diverse and vary among regions. The modified Erasmus GBS Outcome Score (mEGOS), developed with data from Dutch patients, is a clinical model that predicts the risk of walking inability in patients with GBS. The study objective was to validate the mEGOS in the International GBS Outcome Study (IGOS) cohort and to improve its performance and region specificity. METHODS: We used prospective data from the first 1,500 patients included in IGOS, aged ≥6 years and unable to walk independently. We evaluated whether the mEGOS at entry and week 1 could predict the inability to walk unaided at 4 and 26 weeks in the full cohort and in regional subgroups, using 2 measures for model performance: (1) discrimination: area under the receiver operating characteristic curve (AUC) and (2) calibration: observed vs predicted probability of being unable to walk independently. To improve the model predictions, we recalibrated the model containing the overall mEGOS score, without changing the individual predictive factors. Finally, we assessed the predictive ability of the individual factors. RESULTS: For validation of mEGOS at entry, 809 patients were eligible (Europe/North America [n = 677], Asia [n = 76], other [n = 56]), and 671 for validation of mEGOS at week 1 (Europe/North America [n = 563], Asia [n = 65], other [n = 43]). AUC values were >0.7 in all regional subgroups. In the Europe/North America subgroup, observed outcomes were worse than predicted; in Asia, observed outcomes were better than predicted. Recalibration improved model accuracy and enabled the development of a region-specific version for Europe/North America (mEGOS-Eu/NA). Similar to the original mEGOS, severe limb weakness and higher age were the predominant predictors of poor outcome in the IGOS cohort. DISCUSSION: mEGOS is a validated tool to predict the inability to walk unaided at 4 and 26 weeks in patients with GBS, also in countries outside the Netherlands. We developed a region-specific version of mEGOS for patients from Europe/North America. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that the mEGOS accurately predicts the inability to walk unaided at 4 and 26 weeks in patients with GBS. TRIAL REGISTRATION INFORMATION: NCT01582763.

[Evidence based guidelines. Diagnosis and management of Guillain-Barré syndrome in ten steps]. / Guía basada en la evidencia. Diagnóstico y manejo del síndrome de Guillain-Barré en diez pasos.

Guillain-Barré syndrome (GBS) is a rare, but potentially fatal, immune-mediated disease of the peripheral nerves and nerve roots that is usually triggered by infections. The incidence of GBS can therefore increase during outbreaks of infectious diseases, as was seen during the Zika virus epidemics in 2013 in French Polynesia and in 2015 in Latin America. Diagnosis and management of GBS can be complicated as its clinical presentation and disease course are heterogeneous, and no international clinical guidelines are currently available. To support clinicians, especially in the context of an outbreak, we have developed a globally applicable guideline for the diagnosis and management of GBS. The guideline is based on current literature and expert consensus, and has a ten-step structure to facilitate its use in clinical practice. We first provide an introduction to the diagnostic criteria, clinical variants and differential diagnoses of GBS. The ten steps then cover early recognition and diagnosis of GBS, admission to the intensive care unit, treatment indication and selection, monitoring and treatment of disease progression, prediction of clinical course and outcome, and management of complications and sequelae.

El síndrome de Guillain-Barré (SGB) es una enfermedad inmunológica del nervio periférico y las raíces nerviosas, poco frecuente, potencialmente mortal y que suele desencadenarse por infecciones. La incidencia del SGB puede aumentar durante el brote de enfermedades infecciosas, tal como se observó en las epidemias del virus Zika en la Polinesia Francesa en 2013 y en América Latina en 2015. El diagnóstico y el manejo clínico del SGB pueden ser complicados ya que su presentación y el curso de la enfermedad son heterogéneos, y actualmente no se cuenta con guías clínicas internacionales. Para respaldar a los médicos, especialmente en el contexto de un brote de una enfermedad infecciosa, hemos desarrollado una guía clínica aplicable en todo el mundo para el diagnóstico y el tratamiento del SGB. La guía se basa en literatura actualizada y el consenso de expertos, y tiene una estructura de diez pasos para facilitar su uso en la práctica clínica. Inicialmente, brindamos una introducción a los criterios de diagnóstico, variantes clínicas y diagnósticos diferenciales del SGB. Los diez pasos luego abordan el reconocimiento y el diagnóstico temprano del SGB, la admisión a la unidad de cuidados intensivos, indicación y selección de tratamiento, seguimiento y tratamiento de la progresión de la enfermedad, predicción del curso clínico, resultados y tratamiento de complicaciones y secuelas.

Guía basada en la evidencia. Diagnóstico y manejo del síndrome de Guillain-Barré en diez pasos / Evidence based guidelines. Diagnosis and management of Guillain-Barré syndrome in ten steps

Resumen El síndrome de Guillain-Barré (SGB) es una enfermedad inmunológica del nervio periférico y las raíces nerviosas, poco frecuente, potencialmente mortal y que suele desencadenarse por infecciones. La incidencia del SGB puede aumentar durante el brote de enfermedades infecciosas, tal como se observó en las epidemias del virus Zika en la Polinesia Francesa en 2013 y en América Latina en 2015. El diagnóstico y el manejo clínico del SGB pueden ser complicados ya que su presentación y el curso de la enfermedad son heterogéneos, y actualmente no se cuenta con guías clínicas internacionales. Para respaldar a los médicos, especialmente en el contexto de un brote de una enfermedad infecciosa, hemos desarrollado una guía clínica aplicable en todo el mundo para el diagnóstico y el tratamiento del SGB. La guía se basa en literatura actualizada y el consenso de expertos, y tiene una estructura de diez pasos para facilitar su uso en la práctica clínica. Inicialmente, brindamos una introducción a los criterios de diagnóstico, variantes clínicas y diagnósticos diferenciales del SGB. Los diez pasos luego abordan el reconocimiento y el diagnóstico temprano del SGB, la admisión a la unidad de cuidados intensivos, indicación y selección de tratamiento, seguimiento y tratamiento de la progresión de la enfermedad, predicción del curso clínico, resultados y tratamiento de complicaciones y secuelas.

Abstract Guillain-Barré syndrome (GBS) is a rare, but potentially fatal, immune-mediated disease of the peripheral nerves and nerve roots that is usually triggered by infections. The incidence of GBS can therefore increase during outbreaks of infectious diseases, as was seen during the Zika virus epidemics in 2013 in French Polynesia and in 2015 in Latin America. Diagnosis and management of GBS can be complicated as its clinical presentation and disease course are heterogeneous, and no international clinical guidelines are currently available. To support clinicians, especially in the context of an outbreak, we have developed a globally applicable guideline for the diagnosis and management of GBS. The guideline is based on current literature and expert consensus, and has a ten-step structure to facilitate its use in clinical practice. We first provide an introduction to the diag nostic criteria, clinical variants and differential diagnoses of GBS. The ten steps then cover early recognition and diagnosis of GBS, admission to the intensive care unit, treatment indication and selection, monitoring and treatment of disease progression, prediction of clinical course and outcome, and management of complications and sequelae.

Viral protein R polymorphisms in the pathogenesis of HIV-associated acute ischaemic stroke: a case-control study.

HIV-1 viral proteins have been implicated in endothelial dysfunction, which is a major determinant of ischaemic stroke risk in HIV-infected individuals. Polymorphisms in HIV-1 viral protein R (Vpr) may alter its potential to promote endothelial dysfunction, by modifying its effects on viral replication, reactivation of latent cells, upregulation of pro-inflammatory cytokines and infection of macrophages. We analysed Vpr polymorphisms and their association with acute ischaemic stroke by comparing Vpr signature amino acids between 54 HIV-infected individuals with acute ischaemic stroke, and 80 age-matched HIV-infected non-stroke controls. Isoleucine at position 22 and serine at position 41 were associated with ischaemic stroke in HIV. Individuals with stroke had lower CD4 counts and CD4 nadirs than controls. These polymorphisms are unique to individuals with stroke compared to South African subtype C and the control group consensus sequences. Signature Vpr polymorphisms are associated with acute ischaemic stroke in HIV. These may increase stroke risk by promoting endothelial dysfunction and susceptibility to opportunistic infections. Therapeutic targeting of HIV-1 viral proteins may present an additional mechanism of decreasing stroke risk in HIV-infected individuals.

Conceptual framework for establishing the African Stroke Organization.

Africa is the world's most genetically diverse, second largest, and second most populous continent, with over one billion people distributed across 54 countries. With a 23% lifetime risk of stroke, Africa has some of the highest rates of stroke worldwide and many occur in the prime of life with huge economic losses and grave implications for the individual, family, and the society in terms of mental capital, productivity, and socioeconomic progress. Tackling the escalating burden of stroke in Africa requires prioritized, multipronged, and inter-sectoral strategies tailored to the unique African epidemiological, cultural, socioeconomic, and lifestyle landscape. The African Stroke Organization (ASO) is a new pan-African coalition that brings together stroke researchers, clinicians, and other health-care professionals with participation of national and regional stroke societies and stroke support organizations. With a vision to reduce the rapidly increasing burden of stroke in Africa, the ASO has a four-pronged focus on (1) research, (2) capacity building, (3) development of stroke services, and (4) collaboration with all stakeholders. This will be delivered through advocacy, awareness, and empowerment initiatives to bring about people-focused changes in policy, clinical practice, and public education. In the spirit of the African philosophy of Ubuntu "I am because we are," the ASO will harness the power of diversity, inclusiveness, togetherness, and team work to build a strong, enduring, and impactful platform for tackling stroke in Africa.

Original research: Second IVIg course in Guillain-Barré syndrome with poor prognosis: the non-randomised ISID study.

OBJECTIVE: To compare disease course in patients with Guillain-Barré syndrome (GBS) with a poor prognosis who were treated with one or with two intravenous immunoglobulin (IVIg) courses. METHODS: From the International GBS Outcome Study, we selected patients whose modified Erasmus GBS Outcome Score at week 1 predicted a poor prognosis. We compared those treated with one IVIg course to those treated with two IVIg courses. The primary endpoint, the GBS disability scale at 4 weeks, was assessed with multivariable ordinal regression. RESULTS: Of 237 eligible patients, 199 patients received a single IVIg course. Twenty patients received an 'early' second IVIg course (1-2 weeks after start of the first IVIg course) and 18 patients a 'late' second IVIg course (2-4 weeks after start of IVIg). At baseline and 1 week, those receiving two IVIg courses were more disabled than those receiving one course. Compared with the one course group, the adjusted OR for a better GBS disability score at 4 weeks was 0.70 (95%CI 0.16 to 3.04) for the early group and 0.66 (95%CI 0.18 to 2.50) for the late group. The secondary endpoints were not in favour of a second IVIg course. CONCLUSIONS: This observational study did not show better outcomes after a second IVIg course in GBS with poor prognosis. The study was limited by small numbers and baseline imbalances. Lack of improvement was likely an incentive to start a second IVIg course. A prospective randomised trial is needed to evaluate whether a second IVIg course improves outcome in GBS.

Diagnosis and management of Guillain-Barré syndrome in ten steps.

Guillain-Barré syndrome (GBS) is a rare, but potentially fatal, immune-mediated disease of the peripheral nerves and nerve roots that is usually triggered by infections. The incidence of GBS can therefore increase during outbreaks of infectious diseases, as was seen during the Zika virus epidemics in 2013 in French Polynesia and 2015 in Latin America. Diagnosis and management of GBS can be complicated as its clinical presentation and disease course are heterogeneous, and no international clinical guidelines are currently available. To support clinicians, especially in the context of an outbreak, we have developed a globally applicable guideline for the diagnosis and management of GBS. The guideline is based on current literature and expert consensus, and has a ten-step structure to facilitate its use in clinical practice. We first provide an introduction to the diagnostic criteria, clinical variants and differential diagnoses of GBS. The ten steps then cover early recognition and diagnosis of GBS, admission to the intensive care unit, treatment indication and selection, monitoring and treatment of disease progression, prediction of clinical course and outcome, and management of complications and sequelae.

Regional variation of Guillain-Barré syndrome.

Guillain-Barré syndrome is a heterogeneous disorder regarding the clinical presentation, electrophysiological subtype and outcome. Previous single country reports indicate that Guillain-Barré syndrome may differ among regions, but no systematic comparative studies have been conducted. Comparative studies are required to identify factors determining disease susceptibility, variation and prognosis, and to improve diagnostic criteria. The International Guillain-Barré Syndrome Outcome Study is a prospective, observational cohort study including all patients within the diagnostic spectrum, aiming to describe the heterogeneity of Guillain-Barré syndrome worldwide. The current study was based on the first 1000 inclusions with a follow-up of at least 1 year and confirmed the variation in clinical presentation, course and outcome between patients. The full clinical spectrum of Guillain-Barré syndrome was observed in patients from all countries participating in the International Guillain-Barré Syndrome Outcome Study, but the frequency of variants differed between regions. We compared three regions based on geography, income and previous reports of Guillain-Barré syndrome subtypes: 'Europe/Americas', 'Asia' (without Bangladesh), and 'Bangladesh'. We excluded 75 (8%) patients because of alternative diagnoses, protocol violations, or missing data. The predominant clinical variant was sensorimotor in Europe/Americas (n = 387/562, 69%) and Asia (n = 27/63, 43%), and pure motor in Bangladesh (n = 74/107, 69%). Miller Fisher syndrome and Miller Fisher-Guillain-Barré overlap syndrome were more common in Asia (n = 14/63, 22%) than in the other two regions (Europe/Americas: n = 64/562, 11%; Bangladesh: n = 1/107, 1%) (P < 0.001). The predominant electrophysiological subtype was demyelinating in all regions (Europe/Americas: n = 312/573, 55%; Asia: n = 29/65, 45%; Bangladesh: n = 38/94, 40%). The axonal subtype occurred more often in Bangladesh (n = 34/94, 36%) than in Europe/Americas (n = 33/573, 6%) and other Asian countries (n = 4/65, 6%) (P < 0.001). In all regions, patients with the axonal subtype were younger, had fewer sensory deficits, and showed a trend towards poorer recovery compared to patients with the demyelinating subtype. The proportion of patients able to walk unaided after 1 year varied between Asia (n = 31/34, 91%), Europe/Americas (n = 334/404, 83%) and Bangladesh (n = 67/97, 69%) (P = 0.003). A similar variation was seen for mortality, being higher in Bangladesh (n = 19/114, 17%) than in Europe/Americas (n = 23/486, 5%) and Asia (n = 1/45, 2%) (P < 0.001). This study showed that factors related to geography have a major influence on clinical phenotype, disease severity, electrophysiological subtype, and outcome of Guillain-Barré syndrome.

Case Report: Osmotic Demyelination Syndrome in an Adolescent with Neuromyelitis Optica.

A 17-year-old girl presented with intractable vomiting due to area postrema involvement in the first presentation of seronegative neuromyelitis optica (NMO). During the course of her illness, she developed mild hyponatremia, and magnetic resonance imaging revealed abnormalities consistent with the co-occurrence of osmotic demyelination syndrome (ODS). This combination of imaging features is novel, and this case expands the spectrum of brain abnormalities seen in NMO and NMO spectrum disorders. It was suspected that NMO may predispose to ODS by causing astrocyte dysfunction involving aquaporin 4 water channels, which are implicated in both conditions.

The Great Diseases Project: a partnership between Tufts Medical School and the Boston public schools.

Medical schools, although the gatekeepers of much biomedical education and research, rarely engage formally with K-12 educators to influence curriculum content or professional development. This segregation of content experts from teachers creates a knowledge gap that limits inclusion of current biomedical science into high school curricula, affecting both public health literacy and the biomedical pipeline. The authors describe how, in 2009, scientists from Tufts Medical School and Boston public school teachers established a partnership of formal scholarly dialogue to create 11th- to 12th-grade high school curricula about critical health-related concepts, with the goal of increasing scientific literacy and influencing health-related decisions. The curricula are based on the great diseases (infectious diseases, neurological disorders, metabolic disease, and cancer). Unlike most health science curricular interventions that provide circumscribed activities, the curricula are comprehensive, each filling one full term of in-class learning and providing extensive real-time support for the teacher. In this article, the authors describe how they developed and implemented the infectious disease curriculum, and its impacts. The high school teachers and students showed robust gains in content knowledge and critical thinking skills, whereas the Tufts scientists increased their pedagogical knowledge and appreciation for health-related science communication. The results show how formal interactions between medical schools and K-12 educators can be mutually beneficial.