Guillain-Barré syndrome

A Case of Paraneoplastic Guillain-Barré Syndrome Associated with Squamous Cell Carcinoma of the Lung

We report a case of a 61-year-old man with a history of squamous cell carcinoma of the lung presenting with rapidly progressive symmetric ascending weakness with areflexia. The weakness was quickly followed by respiratory decompensation requiring intubation. Lumbar puncture yielded cerebrospinal fluid with elevated protein (177 mg/dL), normal glucose (61 mg/dL), normal red blood cell count (0 per/µl), and normal white blood cell count (0 per/µL). Emergent magnetic resonance imaging of cervical, thoracic, and lumbar spine did not show evidence of metastatic disease, fracture, subluxation, or other causes of cord compression. The patient was diagnosed with acute inflammatory polyneuropathy, also known as Guillain-Barré syndrome. Despite treatment with a five-day course of intravenous immunoglobulin and a subsequent five-day course of plasmapheresis, the patient did not recover respiratory function and died 48 days after diagnosis. To our knowledge, this is the first documented case of Guillain-Barré occurring concomitantly with squamous cell carcinoma of the lung.

Guillain Barré syndrome associated with bladder instillation of Bacille Calmette Guérin (BCG)

Introduction.

Guillain Barré Syndrome (GBS) has rarely been associated with tuberculosis and has been previously reported after Bacille Calmette Guérin (BCG) vaccination, but we report an association of GBS with intra-vesical BCG instillations followed by the clinical picture of disseminated BCGosis.

Case presentation.

A 68-year-old man with bladder carcinoma had a transurethral tumour resection followed by repeated BCG instillations. Catheterization for his eighth dose was traumatic, causing frank haematuria. Ten days later he presented with fevers, myalgia and dyspnoea. Chest X-ray on admission showed micronodular shadowing and a computed tomography scan showed miliary changes in the lungs. Disseminated BCGosis infection was suspected and his symptoms did improve after starting rifamipicin, isoniazid and ethambutol. Over 2 weeks post-admission he developed an unsteady gait, reduced pin-prick sensation below both knees and fingertips, reduced proprioception in both toes and ankles, with absent reflexes in his lower limbs and diminished reflexes in his upper limbs. Nerve conduction studies showed a purely demyelinating sensori-motor peripheral neuropathy in upper and lower limbs, characteristic of GBS.

Conclusion.

To our knowledge this is the first case report of GBS following bladder instillation of BCG. Given the millions of cases of tuberculosis and millions of doses of administered BCG, GBS must be a very rare adverse effect.

Neurofilament light protein levels in cerebrospinal fluid predict long-term disability of Guillain-Barré syndrome: A pilot study

OBJECTIVES

Although the recovery from Guillain-Barré syndrome (GBS) is good in most patients, some develop permanent severe disability or even die. Early predictors would increase the likelihood to identify patients at risk for poor outcome at the acute stage, allowing them intensified therapeutic intervention.

MATERIALS AND METHOD

Eighteen patients with a history of GBS 9-17 years ago were reassessed with scoring of neurological disability and quality of life assessment (QoL). Their previous diagnostic work-up included clinical examination with scoring of disability, neurophysiological investigation, a battery of serology tests for infections, and cerebrospinal fluid (CSF) examination. Aliquots of CSF were frozen, stored for 20-28 years, and analyzed by ELISA for determination of neurofilament light protein (NFL) and glial fibrillary acidic protein (GFAP).

RESULTS

Patients with poor outcome (n = 3) had significantly higher NFL and GFAP levels at GBS nadir than those with good outcome (n = 15, P < .01 and P < .05, respectively). High NFL correlated with more prominent disability and worse QoL at long-term follow-up (r = .694, P < .001, and SF 36 dimension physical component summary (PCS) (r =-.65, P < .05), respectively, whereas GFAP did not correlate with clinical outcome or QoL.

CONCLUSION

High NFL in CSF at the acute stage of GBS seems to predict long-term outcome and might, together with neurophysiological and clinical measures, be useful in treatment decisions and clinical care of GBS.

Immunotherapy of Guillain-Barré syndrome

Guillain-Barré syndrome (GBS), the most common cause of acute neuromuscular weakness and paralysis worldwide, encompasses a group of acute immune-mediated disorders restricted to peripheral nerves and roots. Immune-mediated attack of peripheral nervous system myelin, axons or both is presumed to be triggered by molecular mimicry, with both cell- and humoral-dependent mechanisms implicated in disease pathogenesis. Good circumstantial evidence exists for a pathogenic role for molecular mimicry in GBS pathogenesis, especially with its axonal forms, providing insights that could guide future immunotherapy. Intravenous immunoglobulin (IVIg) and plasma exchange (PE) are the most commonly prescribed immunotherapies for GBS with variable efficacy dependent on GBS subtype, severity at initial presentation and other clinical and electrophysiologic prognostic factors. The mechanisms of action of IVIg and PE are not known definitely. Despite recent significant advances in molecular biology that provide insights into GBS pathogenesis, no advances in therapeutics or significant improvements in patient outcomes have occurred over the past three decades. We summarize the clinical aspects of GBS, its current pathogenesis and immunotherapy, and highlight the potential of leukocyte trafficking inhibitors as novel disease-specific immunotherapeutic drugs.

Prognostic factors of Guillain-Barré syndrome: a 111-case retrospective review

Background

To identify the predictive factors associated with worse prognosis in the Guillain-Barré syndrome (GBS), which can be helpful to fully evaluate the disease progression and provide proper treatments.

Methods

Clinical data of 111 GBS patients who were diagnosed from 2010 to 2015 were collected and retrospectively analyzed.

Results

Patients with diabetes (P=0.031), high blood pressure at admission (P=0.034), uroschesis (P=0.028), fever (P<0.001), ventilator support (P<0.001) during hospitalization, disorder of consciousness (p=0.007) and absence of preceding respiratory infection(P=0.016) were associated with worse outcome at discharge, while abnormal sensation, ataxia, weakness and decrease of tendon reflex seemed not correlated with the Medical Research Council(MRC) score at discharge. Compared with the subtype of acute inflammatory demyelinating polyneuropathy, prognosis of Miller-Fisher syndrome (p<0.001) and cranial nerve variant (p<0.038) were better, but prognosis of acute motor axonal neuropathy(AMAN) was worse (p<0.032). Laboratory examinations at admission showed that hyperglycemia (P=0.002), high leukocyte count (P=0.010), hyperfibrinogenemia (P=0.001), hyponatremia (P=0.020), hypoalbuminemia (P=0.005), abnormal hepatic (P=0.048) and renal (P=0.009) functions were associated with poorer prognosis at discharge, while albuminocytologic dissociation in cerebrospinal fluid, GM1 and GQ1b antibody showed no correlation with the MRC score at discharge. γ-Globulin and glucocorticoid therapies showed no difference in the MRC score at the discharge.

Conclusions

AMAN, diabetes, high blood pressure, uroschesis, high body temperature, ventilator support, consciousness disorder, absence of upper respiratory tract preceding infection, hyperglycemia, hyponatremia, hypoalbuminemia, high leukocyte count, hyperfibrinogenemia, abnormal hepatic and renal function were demonstrated as poor prognostic factors.

Guillain-Barré syndrome in southern China: retrospective analysis of hospitalised patients from 14 provinces in the area south of the Huaihe River

OBJECTIVES

The clinical and epidemiological profiles of Guillain-Barré syndrome (GBS) in southern China have yet to be fully recognised. We aimed to investigate the subtypes of GBS in southern China, compare the clinical features of demyelinating form with that of axonal form and test whether preceding infections and age have influence on the clinical phenotype, disease course and severity of GBS.

METHODS

Medical records of patients with a diagnosis of GBS admitted to 31 tertiary hospitals, located in 14 provinces in southern China, from 1 January 2013 to 30 September 2016, were collected and retrospectively reviewed.

RESULTS

Finally. 1056 patients, including 887 classic GBS and 169 variants, were enrolled. The 661 classic patients with available electromyographic data were grouped as having acute inflammatory demyelinating polyneuropathy (AIDP, 49.0%), acute motor axonal neuropathy (AMAN, 18.8%), inexcitable (0.9%) and equivocal (31.3%). In contrast to AIDP, patients with AMAN were characterised by earlier nadir (P=0.000), higher Hughes score at nadir (P=0.003) and at discharge (P=0.000). Preceding upper respiratory infections were identified in 369 (34.9%) patients, who were more inclined to develop AIDP (P=0.000) and Miller-Fisher syndrome (P=0.027), whereas gastrointestinal infection were found in 89 (8.4%) patients, who were more prone to develop AMAN (P=0.000), with more severe illness (P=0.001) and longer hospital stay (P=0.009). Children (≤15 years) and the elderly (≥56 years) were more severe at nadir, the elderly had the longest hospital stay (P=0.023).

CONCLUSION

AIDP is the predominant form in southern China, which is different from data of northern China. The different subtypes, preceding infection and age of onset can partially determine the disease progression, severity and short-term recovery speed of GBS.

CLINICAL TRIAL REGISTRATION

ChiCTR-RRC-17014152.

Epidemiology and Clinical Features of Guillain-Barre Syndrome in Isfahan, Iran

Background:

Guillain-Barre syndrome (GBS) is an immune-mediated peripheral neuropathy. We compared clinical, laboratory characteristics, and disease course of GBS subtypes in a large group of Iranian patients in Isfahan.

Materials and Methods:

We collected data from patients who were admitted to Alzahra referral university Hospital, Isfahan, Iran with a diagnosis of GBS. In this population-based cross-sectional research, characteristic of 388 cases with GBS between 2010 and 2015 were studied.

Results:

The current study recruited 388 patients with GBS including 241 males (62.1%) and 147 females (37.9%) with a mean age of 42.78 ± 21.34. Patients with polyradiculopathy had the highest mean age of 55.12 ± 20.59 years, whereas the least age was seen in acute motor axonal neuropathy (AMAN) with the mean of 36.30 ± 18.71 years. The frequency of GBS witnessed the highest frequency in spring with 113 cases (29.1%) and winter with 101 cases (26%). Patients' electrodiagnostic findings indicated that the highest frequency pertained to AMSAN with 93 cases (24%), whereas the least frequent diagnosis was acute Polyradiculopathy with 8 cases (2.1%). Most of the patients did not have any infections (53.6%) and among patients with infections, AMSAN had the highest frequency (22.9%) and finally, patients with AMSAN and AMAN had a higher length of stay.

Conclusion:

The study demonstrated incidence, sex distribution, preceding infection, and surgery similar to previous studies. However, our data differs from a study in Tehran that showed acute inflammatory demyelinating polyradiculoneuropathy is more prevalent than other types and we found a seasonal preponderance in cold months, particularly in axonal types.

Guillain-Barré Syndrome Associated With Zika Virus Infection in Martinique in 2016: A Prospective Study

Background

Guillain-Barré syndrome (GBS) has been reported to be associated with Zika virus (ZIKV) infection in case reports and retrospective studies, mostly on the basis of serological tests, with the problematic cross-reacting antibodies of the Flavivirus genus. Some GBS cases do not exhibit a high level of diagnostic certainty. This prospective study aimed to describe the clinical profiles and the frequency of GBS associated with ZIKV during the ZIKV outbreak in Martinique in 2016.

Methods

We recorded prospective data from GBS meeting levels 1 or 2 of diagnostic certainty for the Brighton Collaboration, with proof of recent ZIKV infection and negative screening for etiologies of GBS.

Results

Of the sample of 34 patients with suspected GBS during the outbreak, 30 had a proven presence of GBS, and 23 had a recent ZIKV infection. The estimated GBS incidence rate ratio (2016 vs 2006-2015) was 4.52 (95% confidence interval, 2.80-7.64; P = .0001). Recent ZIKV infection was confirmed by urine reverse-transcription polymerase chain reaction (RT-PCR) analysis in 17 cases and by serology in 6 cases. Patients, 65% of whom were male, had a median age of 61 years (interquartile range, 56-71 years) and experienced severe GBS. Electrophysiological tests were consistent with the primary demyelinating form of the disease.

Conclusions

ZIKV infection is usually benign, when symptomatic, but in countries at risk of ZIKV epidemics, adequate intensive care bed capacity is required for management of severe GBS cases. Arbovirus RNA detection by RT-PCR should be part of the management of GBS cases.

Clinical factors associated with Guillain-Barré syndrome following surgery

Background

We sought to identify clinical associations and potential triggers of Guillain-Barré syndrome (GBS) within 6 weeks of surgery.

Methods

We retrospectively reviewed consecutive patients diagnosed with GBS within 6 weeks of a surgery between January 1995 and June 2014 at Mayo Clinic. Postsurgical GBS was defined as symptom onset within 6 weeks of surgery. Patients with postsurgical GBS were compared with patients who did not have a surgery prior to GBS onset to determine differences between groups.

Results

A total of 208 patients with GBS, median age 55 years (interquartile range [IQR] 41-68), were included. Nineteen patients (9.1%) developed postsurgical GBS. Median duration from the surgery to onset of first GBS symptom was 15 days (IQR 9-37). The main types of surgeries preceding GBS were gastrointestinal, orthopedic, and cardiac. General anesthesia was used in 18 (95%) and conscious sedation in 1 (5%) patient. Among the 19 patients with postsurgical GBS, 11 (57.9%) had a known diagnosis of malignancy. Autoimmune conditions were present in 5 (26.3%) patients. Postoperative infection was found in 4 (21%) patients. On univariate analysis, the factors that showed an association with postsurgical GBS were age (p = 0.02), malignancy (p ≤ 0.0004), active malignancy (p = 0.03), preexisting autoimmune disorder (p = 0.02), and infection (p = 0.0001). On multivariate analysis, only active malignancy (0.03) remained associated.

Conclusions

Surgery antedated GBS in 9.1% of patients. Postsurgical GBS was more common in patients with an active malignancy. A prospective study is needed to determine whether active malignancy represents an independent risk factor for the development of postsurgical GBS.

An assessment of public health surveillance of Zika virus infection and potentially associated outcomes in Latin America

BACKGROUND

We evaluated whether outbreaks of Zika virus (ZIKV) infection, newborn microcephaly, and Guillain-Barré syndrome (GBS) in Latin America may be detected through current surveillance systems, and how cases detected through surveillance may increase health care burden.

METHODS

We estimated the sensitivity and specificity of surveillance case definitions using published data. We assumed a 10% ZIKV infection risk during a non-outbreak period and hypothetical increases in risk during an outbreak period. We used sensitivity and specificity estimates to correct for non-differential misclassification, and calculated a misclassification-corrected relative risk comparing both periods. To identify the smallest hypothetical increase in risk resulting in a detectable outbreak we compared the misclassification-corrected relative risk to the relative risk corresponding to the upper limit of the endemic channel (mean + 2 SD). We also estimated the proportion of false positive cases detected during the outbreak. We followed the same approach for microcephaly and GBS, but assumed the risk of ZIKV infection doubled during the outbreak, and ZIKV infection increased the risk of both diseases.

RESULTS

ZIKV infection outbreaks were not detectable through non-serological surveillance. Outbreaks were detectable through serologic surveillance if infection risk increased by at least 10%, but more than 50% of all cases were false positive. Outbreaks of severe microcephaly were detected if ZIKV infection increased prevalence of this condition by at least 24.0 times. When ZIKV infection did not increase the prevalence of severe microcephaly, 34.7 to 82.5% of all cases were false positive, depending on diagnostic accuracy. GBS outbreaks were detected if ZIKV infection increased the GBS risk by at least seven times. For optimal GBS diagnosis accuracy, the proportion of false positive cases ranged from 29 to 54% and from 45 to 56% depending on the incidence of GBS mimics.

CONCLUSIONS

Current surveillance systems have a low probability of detecting outbreaks of ZIKV infection, severe microcephaly, and GBS, and could result in significant increases in health care burden, due to the detection of large numbers of false positive cases. In view of these limitations, Latin American countries should consider alternative options for surveillance.

Investigating the Association Between the Caecal Microbiomes of Broilers and Campylobacter Burden

One of the major transmission routes for the foodborne bacterial pathogen Campylobacter is undercooked poultry meat, contaminated from intestinal contents during processing. In broilers, Campylobacter can grow to very high densities in the caeca, and is often considered to be a commensal or an opportunistic pathogen in poultry. Reduction of caecal loads of Campylobacter may assist in lowering incidence rates of Campylobacter food poisoning. To achieve this, there needs to be a better understanding of the dynamics of Campylobacter colonization in its natural niche, and the effect of the local microbiome on colonization. Previous studies have shown that the microbiome differed between Campylobacter colonized and non-colonized chicken intestinal samples. To characterize the microbiome of Campylobacter-colonized broilers, caecal samples of 100 randomly selected birds from four farms were analyzed using amplified 16S rRNA gene sequences. Bacterial taxonomic analysis indicated that inter-farm variation was greater than intra-farm variation. The two most common bacterial groups were Bacteroidetes and Firmicutes which were present in all samples and constituted 29.7-63.5 and 30.2-59.8% of the bacteria present, respectively. Campylobacter was cultured from all samples, ranging from 2 to 9 log₁₀ CFU g^-1. There was no clear link between Campylobacter counts and Firmicutes, Bacteroidetes, or Tenericutes levels in the 16S rRNA operational taxonomic unit (OTU)-based analysis of the caecal microbiome, but samples with high Campylobacter counts (>9 log CFU g^-1) contained increased levels of Enterobacteriaceae. A decrease in Lactobacillus abundance in chicken caeca was also associated with high Campylobacter loads. The reported associations with Lactobacillus and Enterobacteriaceae match changes in the intestinal microbiome of chickens and mice previously reported for Campylobacter infection, and raises the question about temporality and causation; as to whether increases in Campylobacter loads create conditions adverse to Lactobacilli and/or beneficial to Enterobacteriaceae, or that changes in Lactobacilli and Enterobacteriaceae levels created conditions beneficial for Campylobacter colonization. If these changes can be controlled, this may open opportunities for modulation of chicken microbiota to reduce Campylobacter levels for improved food safety.

Three-Year Follow-Up Study in Patients with Guillain-Barré Syndrome

A majority of patients with Guillain-Barré syndrome (GBS) have tendency of a good recovery. Our aim was to evaluate the outcome of the disease 1 and 3 years after GBS symptom onset. Methods: During 2014, GBS was diagnosed in 82 patients in seven tertiary healthcare centers. Neurological follow-up was conducted in 57 (70%) patients after 1 year, and in 54 (66%) after 3 years. Functional disability was estimated according to the GBS disability scale (GDS), with a score of 0-3 indicating mild disability and a score of 4-6 indicating severe disability during acute phase, whereas a score >1 indicated poor recovery on follow-ups. Visual analog scale was used to assess sensory symptoms and musculoskelatal pain, and Krupp’s Fatigue Severity Scale was used to asses fatigue. Results: Poor functional outcome was found in 39% of GBS patients at year 1 and 30% at year 3. Paresthesias/dysesthesias were detected in 60% of patients after 1 year and 43% after 3 years. Musculoskeletal pain was present in 40% of patients at year 1 and 33% at year 3. Significant fatigue after 1 year was found in 21% of subjects and after 3 years in 7%. Parameters associated with poor functional outcome after 1 year were age >55 years (p=0.05), severe disability at admission (p<0.05), and on discharge (p<0.01). Poor functional outcome after 3 years was associated with male gender (p<0.05) and severe disability on discharge (p=0.06). Conclusion: One and even three years after GBS onset, a substantial number of patients had neurological sequelae, including functional disability, sensory symptoms, pain, and fatigue.

Antibiotic Sensitivity Profiling and Virulence Potential of Campylobacter jejuni Isolates from Estuarine Water in the Eastern Cape Province, South Africa

Campylobacter jejuni (CJ) is a zoonotic microbe and a major causative organism of diarrheal infection in humans that often has its functional characteristics inactivated in stressed conditions. The current study assessed the correlation between recovered CJ and water quality parameters and the drug sensitivity patterns of the pathogen to frontline antibiotics in human and veterinary medicine. Water samples (n = 244) from rivers/estuarines were collected from April⁻September 2016, and physicochemical conditions were recorded on-site. CJ was isolated from the samples using standard microbiological methods and subjected to sensitivity testing to 10 antibiotics. Mean CJ counts were between 1 and 5 logs (CFU/mL). Ninety-five isolates confirmed as CJ by PCR showed varying rates of resistance. Sensitivity testing showed resistance to tetracycline (100%), azithromycin (92%), clindamycin (84.2%), clarithromycin and doxycycline (80%), ciprofloxacin (77.8%), vancomycin (70.5%), erythromycin (70%), metronidazole (36.8%) and nalidixic acid (30.5%). Virulence encoding genes were detected in the majority 80/95, 84.2%) of the confirmed isolates from cdtB; 60/95 (63.2%) from cstII; 49/95 (51.6%) from cadF; 45/95 (47.4%) from clpP; 30/95 (31.6%) from htrB, and 0/95 (0%) from csrA. A multiple resistance cmeABC active efflux pump system was present in 69/95 (72.6) isolates. The presence of CJ was positively correlated with temperature (r = 0.17), pH (r = 0.02), dissolved oxygen (r = 0.31), and turbidity (r = 0.23) but negatively correlated with salinity (r = −0.39) and conductivity (r = −0.28). The detection of multidrug resistant CJ strains from estuarine water and the differential gene expressions they possess indicates a potential hazard to humans. Moreover, the negative correlation between the presence of the pathogen and physicochemical parameters such as salinity indicates possible complementary expression of stress tolerance response mechanisms by wild-type CJ strains.

Can we assess severity of Guillain-Barré syndrome using absolute monocyte count?

INTRODUCTION

Guillain-Barré syndrome (GBS) is an inflammatory demyelinating autoimmune disease, associated with blood-nerve barrier breakdown, inflammatory cells infiltration, and cytokine leakage in the peripheral nervous system. Currently, it has been revealed that monocytes play key roles in the inflammatory response. Therefore, we aimed to assess the correlation between monocyte count and GBS in this study.

METHODS

Retrospective study was conducted in 114 patients with GBS and 120 age- and gender-matched individuals.

RESULTS

Absolute monocyte count in patients with GBS was higher than that in healthy controls (0.61 ± 0.24 vs 0.41 ± 0.10; P  < .001). Interestingly, monocyte count had significant positive correlations with CRP, ESR, and disease severity of GBS (r = .244, P = .009; r = .269, P = .004; r = .322, P < .001). A cutoff value of 0.515 for monocyte count was observed in patients with GBS (areas under the curve = 0.808, 95% confidence interval = 0.749-0.868, P  < .001). Meanwhile, absolute monocyte count was independently associated with GBS in logistic regression analysis (odds ratio = 2.291, 95% confidence interval = 3.557-27.493, P < .001).

CONCLUSION

Our findings demonstrated that elevated monocyte count is independently associated with GBS patients, and suggested monocyte count is positively associated with disease severity of GBS.

Beneficial or Harmful Role of Macrophages in Guillain-Barré Syndrome and Experimental Autoimmune Neuritis

Guillain-Barré syndrome (GBS), an immune-mediated demyelinating peripheral neuropathy, is characterized by acute weakness of the extremities and areflexia or hyporeflexia. Experimental autoimmune neuritis (EAN) is a common animal model for GBS, which represents a CD4+ T cell-mediated inflammatory autoimmune demyelination of the peripheral nervous system (PNS), and is used to investigate the pathogenic mechanism of GBS. It has been found that macrophages play a critical role in the pathogenesis of both GBS and EAN. Macrophages have been primarily classified into two major phenotypes: proinflammatory macrophages (M1) and anti-inflammatory macrophages (M2). The two different macrophage subsets M1 and M2 may play a decisive role in initiation and development of GBS and EAN. However, recently, it has been indicated that the roles of macrophages in immune regulation and autoimmune diseases are more complex than those suggested by a simple M1-M2 dichotomy. Macrophages might exert either inflammatory or anti-inflammatory effect by secreting pro- or anti-inflammatory cytokines, and either inducing the activation of T cells to mediate immune response, resulting in inflammation and demyelination in the PNS, or promoting disease recovery. In this review, we summarize the dual roles of macrophages in GBS and EAN and explore the mechanism of macrophage polarization to provide a potential therapeutic approach for GBS in the future.

Beneficial or Harmful Role of Macrophages in Guillain-Barré Syndrome and Experimental Autoimmune Neuritis

Guillain-Barré syndrome (GBS), an immune-mediated demyelinating peripheral neuropathy, is characterized by acute weakness of the extremities and areflexia or hyporeflexia. Experimental autoimmune neuritis (EAN) is a common animal model for GBS, which represents a CD4⁺ T cell-mediated inflammatory autoimmune demyelination of the peripheral nervous system (PNS), and is used to investigate the pathogenic mechanism of GBS. It has been found that macrophages play a critical role in the pathogenesis of both GBS and EAN. Macrophages have been primarily classified into two major phenotypes: proinflammatory macrophages (M1) and anti-inflammatory macrophages (M2). The two different macrophage subsets M1 and M2 may play a decisive role in initiation and development of GBS and EAN. However, recently, it has been indicated that the roles of macrophages in immune regulation and autoimmune diseases are more complex than those suggested by a simple M1-M2 dichotomy. Macrophages might exert either inflammatory or anti-inflammatory effect by secreting pro- or anti-inflammatory cytokines, and either inducing the activation of T cells to mediate immune response, resulting in inflammation and demyelination in the PNS, or promoting disease recovery. In this review, we summarize the dual roles of macrophages in GBS and EAN and explore the mechanism of macrophage polarization to provide a potential therapeutic approach for GBS in the future.

Beneficial or Harmful Role of Macrophages in Guillain-Barré Syndrome and Experimental Autoimmune Neuritis

Guillain-Barré syndrome (GBS), an immune-mediated demyelinating peripheral neuropathy, is characterized by acute weakness of the extremities and areflexia or hyporeflexia. Experimental autoimmune neuritis (EAN) is a common animal model for GBS, which represents a CD4⁺ T cell-mediated inflammatory autoimmune demyelination of the peripheral nervous system (PNS), and is used to investigate the pathogenic mechanism of GBS. It has been found that macrophages play a critical role in the pathogenesis of both GBS and EAN. Macrophages have been primarily classified into two major phenotypes: proinflammatory macrophages (M1) and anti-inflammatory macrophages (M2). The two different macrophage subsets M1 and M2 may play a decisive role in initiation and development of GBS and EAN. However, recently, it has been indicated that the roles of macrophages in immune regulation and autoimmune diseases are more complex than those suggested by a simple M1-M2 dichotomy. Macrophages might exert either inflammatory or anti-inflammatory effect by secreting pro- or anti-inflammatory cytokines, and either inducing the activation of T cells to mediate immune response, resulting in inflammation and demyelination in the PNS, or promoting disease recovery. In this review, we summarize the dual roles of macrophages in GBS and EAN and explore the mechanism of macrophage polarization to provide a potential therapeutic approach for GBS in the future.

Correlative study between C-reactive protein, clinical severity, and nerve conduction studies in Guillain-Barrè syndrome

Background

Guillain-Barre' syndrome (GBS) is a serious autoimmune disorder in which the immune system attacks healthy nerve cells of the peripheral nervous system causing polyradiculoneuropathy which leads to weakness, numbness, and tingling, and can eventually cause paralysis. Autoimmune conditions like GBS can induce a high level of inflammation resulting in an increase in the C-reactive protein( CRP) production. The aim of this study is to assess the relationship between CRP level and the clinical severity as well as the electrophysiological findings of nerve conduction studies in patients with GBS.

Methods

Twenty- four patients (10 males &14 females) with ages ranged from 14 to 50 years and a mean age of 33.46 ±12.25 years who fulfilled the clinical criteria for diagnosing GBS were recruited within the first 2 weeks of onset of illness, in a cross- section study. They underwent general and neurological examination. Nerve conduction studies as well as assessment of serum CRP level were done.

Results

There was a statistically significant positive correlation between clinical severity assessed by (Hughes disability scale) and serum CRP level in GBS patients. Multivariate logistic regression analysis showed that both gastroenteritis, cranio-bulbar affection, need for mechanical ventilation (MV), disability score >4, and absent motor and sensory responses were significantly associated with high serum CRP level >6mg/dl.

Conclusions

The results of this study support the hypothesis that in GBS patients, gastroenteritis, craniobulbar affection, need for MV, disability score >4, and absent motor and sensory nerve responses were significantly related to high serum CRP level. This reflects the negative impact of the inflammatory response elicited by high CRP level on clinical severity in GBS patients, and so it may be used as a prognostic marker of clinical severity of GBS and this can help in therapeutic decision making.

Safety and efficacy of eculizumab in Guillain-Barré syndrome: a multicentre, double-blind, randomised phase 2 trial

BACKGROUND

Despite the introduction of plasmapheresis and immunoglobulin therapy, many patients with Guillain-Barré syndrome still have an incomplete recovery. Evidence from pathogenesis studies suggests the involvement of complement-mediated peripheral nerve damage. We aimed to investigate the safety and efficacy of eculizumab, a humanised monoclonal antibody against the complement protein C5, in patients with severe Guillain-Barré syndrome.

METHODS

This study was a 24 week, multicentre, double-blind, placebo-controlled, randomised phase 2 trial done at 13 hospitals in Japan. Eligible patients with Guillain-Barré syndrome were aged 18 years or older and could not walk independently (Guillain-Barré syndrome functional grade 3-5). Patients were randomly assigned (2:1) to receive 4 weeks of intravenous immunoglobulin plus either eculizumab (900 mg) or placebo; randomisation was done via a computer-generated process and web response system with minimisation for functional grade and age. The study had a parallel non-comparative single-arm outcome measure. The primary outcomes were efficacy (the proportion of patients with restored ability to walk independently [functional grade ≤2] at week 4) in the eculizumab group and safety in the full analysis set. For the efficacy endpoint, we predefined a response rate threshold of the lower 90% CI boundary exceeding 50%. This trial is registered with ClinicalTrials.gov, number, NCT02493725.

FINDINGS

Between Aug 10, 2015, and April 21, 2016, 34 patients were assigned to receive either eculizumab (n=23) or placebo (n=11). At week 4, the proportion of the patients able to walk independently (functional grade ≤2) was 61% (90% CI 42-78; n=14) in the eculizumab group, and 45% (20-73; n=5) in the placebo group. Adverse events occurred in all 34 patients. Three patients had serious adverse events: two in the eculizumab group (anaphylaxis in one patient and intracranial haemorrhage and abscess in another patient) and one in the placebo group (depression). The possibility that anaphylaxis and intracranial abscess were related to eculizumab could not be excluded. No deaths or meningococcal infections occurred.

INTERPRETATION

The primary outcome measure did not reach the predefined response rate. However, because this is a small study without statistical comparison with the placebo group, the efficacy and safety of eculizumab could be investigated in larger, randomised controlled trials.

FUNDING

The Japan Agency for Medical Research and Development, Ministry of Health, Labor and Welfare, and Alexion Pharmaceuticals.

Guillain-Barré syndrome and Zika virus outbreaks

PURPOSE OF REVIEW

Arboviruses have been associated with central and peripheral nervous system injuries, in special the flaviviruses. Guillain-Barré syndrome (GBS), transverse myelitis, meningoencephalitis, ophthalmological manifestations, and other neurological complications have been recently associated to Zika virus (ZIKV) infection. In this review, we aim to analyze the epidemiological aspects, possible pathophysiology, and what we have learned about the clinical and laboratory findings, as well as treatment of patients with ZIKV-associated neurological complications.

RECENT FINDINGS

In the last decades, case series have suggested a possible link between flaviviruses and development of GBS. Recently, large outbreaks of ZIKV infection in Asia and the Americas have led to an increased incidence of GBS in these territories. Rapidly, several case reports and case series have reported an increase of all clinical forms and electrophysiological patterns of GBS, also including cases with associated central nervous system involvement. Finally, cases suggestive of acute transient polyneuritis, as well as acute and progressive postinfectious neuropathies associated to ZIKV infection have been reported, questioning the usually implicated mechanisms of neuronal injury.

SUMMARY

The recent ZIKV outbreaks have triggered the occurrence of a myriad of neurological manifestations likely associated to this arbovirosis, in special GBS and its variants.

[Approach for identifying of treatment option for pediatric patients in Guillain-Barre syndrome considering results of pharmacoeconomic analysis]

AIM

A pharmacoeconomic analysis of direct costs on treatment with high dose intravenous immunoglobulins (IVIG) and plasmapheresis (PP) in children.

MATERIAL AND METHODS

Literature data on the pathogenesis of Guillain-Barre syndrome (GBS) were analyzed. The results of pharmacoeconomic analysis of direct costs on treatment of GBS using IVIG and PP are presented. Risks for complications during treatment with IVIG and PP are calculated.

RESULTS AND CONCLUSION

The pharmacoeconomic analysis demonstrates comparable costs of treatment with IVIG or PP in the Russian Federation. Nevertheless, a less number of complications, convenience in use and the good safety and tolerability profile make it more preferable to this group of patients. In a clinical case of a 7-year child described in the article, treatment with 10% IVIG - privigen in dose 2 g/kg during 5 days started in the 3^rd week of disease showed a marked positive effect.

Autoimmune Neurological Conditions Associated With Zika Virus Infection

Zika virus (ZIKV) is an emerging flavivirus rapidly spreading throughout the tropical Americas. Aedes mosquitoes is the principal way of transmission of the virus to humans. ZIKV can be spread by transplacental, perinatal, and body fluids. ZIKV infection is often asymptomatic and those with symptoms present minor illness after 3 to 12 days of incubation, characterized by a mild and self-limiting disease with low-grade fever, conjunctivitis, widespread pruritic maculopapular rash, arthralgia and myalgia. ZIKV has been linked to a number of central and peripheral nervous system injuries such as Guillain-Barré syndrome (GBS), transverse myelitis (TM), meningoencephalitis, ophthalmological manifestations, and other neurological complications. Nevertheless, mechanisms of host-pathogen neuro-immune interactions remain incompletely elucidated. This review provides a critical discussion about the possible mechanisms underlying the development of autoimmune neurological conditions associated with Zika virus infection.

Current priorities in the Zika response

Zika virus (ZIKV), a single-stranded RNA virus of the Flaviviridae family, is an arbovirus (viruses transmitted by arthropods) transmitted to humans and non-human primates through the bites of infected female Aedes sp. mosquitoes. Although first isolated in 1947, it only recently emerged as a global threat, present in several countries resulting in a pandemic scenario. ZIKV infections may have severe outcomes, such as neurological impairment, and with the intrinsic ability of inducing microcephaly in fetuses of infected pregnant women, the virus has become a major public health problem. This review discusses some advances in diagnosis; vaccine development and the problems associated with their administration; the importance of the cross-reactivity with other flaviviruses in protecting or worsening the disease; the implications of the recent outbreak caused by the virus in the world; and future prospects for the complete understanding of this disease.

Zika virus outbreak in New Caledonia and Guillain-Barré syndrome: a case-control study

Zika virus (ZIKV) infection has been associated with neurologic disorders including Guillain-Barré syndrome (GBS). In New Caledonia during the ZIKV outbreak (2014-2015), case-control and retrospective studies have been performed to assess the link between ZIKV and GBS. Among the 15 cases included, 33% had evidence of a recent ZIKV infection compared to only 3.3% in the 30 controls involved. All patients were Melanesian, had facial diplegia and similar neurophysiological pattern consistent with acute inflammatory demyelinating polyneuropathy, and recovered well. Furthermore, during the peak of ZIKV transmission, we observed a number of GBS cases higher than the calculated upper limit, emphasizing the fact that ZIKV is now a major trigger of GBS.

Immune-mediated Neuropathies Our Experience over 3 Years

Introduction

Immune-mediated peripheral neuropathy is the term applied to a spectrum of peripheral nerve disorders where immune dysregulation plays a role. Therefore, they are treatable. We analyzed the cases seen in the past 3 years by us and evaluated the clinical, laboratory, and outcome parameters in these patients.

Patients and Methods

Consecutive patients seen by the authors and diagnosed as immune-mediated neuropathy were analyzed for etiology, pathology, and outcome assessed.

Results

A total of sixty patients, 31 acute and 29 chronic neuropathies, were identified. Their subtypes treatment and outcome assessed. Males were significantly more in both acute and chronic cases. Miller Fisher 4, AMAN 1, paraplegic type 1, motor dominant type 19, Sensory-motor 1, MADSAM 3, Bifacial 2. Nonsystemic vasculitis was seen in 16 out of 29 chronic neuropathy and HIV, POEMS, and diabetes mellitus one each.

Discussion

There is a spectrum of immune-mediated neuropathy which varies in clinical course, response to treatment, etc., Small percentage of uncommon cases are seen. In this group, mortality was nil and morbidity was minimal.

Conclusion

Immune-mediated neuropathies are treatable and hence should be diagnosed early for good quality outcome.

An idiopathic thrombocytopenic purpura with polyneuropathy

Concurrent association of idiopathic thrombocytopenic purpura (ITP) and peripheral neuropathy is a rare condition. There are only few case reports published concerning peripheral neuropathy with ITP. One of the etiopathogenetic mechanisms proposed is intraneural hemorrhage, but the pathogenesis is not fully understood. Autoimmune nature with common antibodies to the platelets and the nerve´s myelin sheath should also be considered. Here we describe a 47-year-old woman, with a family history of autoimmune diseases. She was diagnosed 2 years ago with ITP and later developed a chronic combined inflammatory demyelinating polyneuropathy. Treatment with high-dose steroids was initiated with a poor response. The patient showed a clear improvement in platelet count and in the peripheral neuropathy symptoms when treatment with intravenous immunoglobulin was administered. Common etiologic mechanism of the two diseases should be considered, both, because of the simultaneous time of development and a similar response to intravenous immunoglobulin treatment.

The clinical features of combined central and peripheral demyelination in Chinese patients

BACKGROUND

Combined central and peripheral demyelination (CCPD) is rare and has never been reported as a spectrum disease in Han Chinese population.

OBJECTIVES

To study the clinical features of CCPD in Han Chinese patients.

METHODS

Twenty-two CCPD patients were selected from 788 demyelination cases. We reviewed and compared the clinical manifestation, laboratory data, electrophysiological examination, MRI and the prognosis.

RESULTS

CCPD patients presented with sensory disturbance (86.4%), plegia (77.3%), cranial nerve involvement (77.3%), abnormal deep tendon reflexes (72.7%). CSF data showed increased CSF protein in 81% patients. Oligoclonal IgG bands (OB) were negative. Cortical or juxtacortical, periventricular, infratentorial lesions, thoracic and cervical spinal cord were mostly affected. Visual evoked potentials indicated optic nerves demyelinating in 50% cases. 21 CCPD patients were treated with intravenous immunoglobulin or steroids or both of them, and the efficacy was 33.3%, 54.5%, 71.4%, respectively. One case that showed no response to steroids plus intravenous immunoglobulin treatment was improved significantly after using cyclophosphamide.

CONCLUSIONS

CCPD is a spectrum disease that can't be regarded as a simple combination of MS and CIDP. A suspected CCPD should receive brain and spinal MRI as well as electrophysiological examination to obtain a precise diagnosis.

Guillain-Barré syndrome following varicella-zoster virus infection

We describe the frequency, clinical features, and electrophysiological and immunological phenotypes of Guillain-Barré Syndrome (GBS) patients treated at a single institution in Bangladesh who had preceding chicken pox (primary Varicella-zoster virus [VZV] infection) within 4 weeks of GBS onset. A literature review of GBS cases preceding VZV infection is also provided. Diagnosis of GBS was based on the National Institute of Neurological Disorders and Stroke criteria for GBS. Serum anti-VZV IgM and IgG antibodies were quantified by indirect chemiluminescence immunoassay (CLIA); anti-Campylobacter jejuni IgG, IgM, and IgA antibodies and anti-ganglioside GM1 IgM and IgG antibodies, by enzyme-linked immunosorbent assays. Neurophysiologic subtypes were categorized following the Hadden criteria. Of 536 patients with GBS, 7 (1.3%) had chicken pox within 4 weeks before GBS onset. Four of the seven cases were male (age range, 23 to 40 years old). All seven patients were bed-bound, six had sensory symptoms, and three required mechanical ventilation for respiratory failure. All seven patients had CSF albuminocytologic dissociation and evidence of demyelination in nerve conduction studies. Anti-VZV IgM antibodies were present and anti-GM1 and anti-Campylobacter jejuni lipo-oligosaccharides (LOS) were negative in all cases. All patients had excellent outcome at 1 year (able to run). A systematic literature review of GBS cases related to VZV revealed 39 previously reported patients with comparable clinical presentations and outcomes, of which 36 had neurophysiologic evidence of demyelination. VZV infection is associated with the demyelinating subtype of GBS, clearly distinct from the axonal form of GBS that predominate in countries like Bangladesh.

Complete response to pembrolizumab in a patient with metastatic colon cancer with microsatellite instability and a history of Guillain-Barre syndrome

Currently, clinical trials with programmed death-1 (PD-1) inhibitors exclude patients with preexisting autoimmune disorders such as Guillain-Barre syndrome (GBS). Therefore, the scientific literature has limited information about the efficacy and safety of PD-1 inhibitors in cancer patients with autoimmune disorders. Immune checkpoint inhibitors can exacerbate preexisting autoimmune disorders and can induce severe immune-related adverse events. Here, we report the case of a 73-year-old female patient with history of GBS and mismatch repair deficient metastatic colorectal cancer who achieved a durable complete response to pembrolizumab. The patient was maintained on intravenous immunoglobulin (IVIG) during her treatment without any neurological exacerbations. This case highlights the feasibility of PD-1 inhibitors in select patients with neurological autoimmune disorders and calls for more systematic evaluation of checkpoint inhibitors in patients with cancer and GBS, especially with the known link between this disorder and malignancy.

Neuromuscular complications of immune checkpoint inhibitor therapy

Immune checkpoint inhibitor (ICPI) therapy unleashes the body's natural immune system to fight cancer. ICPIs improve overall cancer survival, however, the unbridling of the immune system may induce a variety of immune-related adverse events. Neuromuscular immune complications are rare but they can be severe. Myasthenia gravis and inflammatory neuropathy are the most common neuromuscular adverse events but a variety of others including inflammatory myopathy are reported. The pathophysiologic mechanism of these autoimmune disorders may differ from that of non-ICPI-related immune diseases. Accordingly, while the optimal treatment for ICPI-related neuromuscular disorders generally follows a traditional paradigm, there are important novel considerations in selecting appropriate immunosuppressive therapy. This review presents 2 new cases, a summary of neuromuscular ICPI complications, and an approach to the diagnosis and treatment of these disorders. Muscle Nerve, 2018.

Serial electromyographic findings in Guillain-Barré syndrome patients

We sought to investigate electromyographic characteristics of Guillain-Barré syndrome (GBS) patients in the recovery phase by using serial electromyography (EMG). We included seven GBS patients and assessed their neurologic function at admission and 2, 3 and 6 months post onset using Hughes Functional Grading Scale scores. All patients underwent serial electromyographic assessment of compound muscle action potentials (CMAPs), mean conduction velocity (MCV), and distal motor latency (DML) of peripheral nerves. F wave was recorded of the median nerve and ulnar nerve. All seven patients had a Hughes Functional Grading Scale score between 3 and 6 at admission, while three patients at 2 months, one patient at 3 months, and no patient at 6 months post GBS onset had a Hughes Functional Grading Scale score between 3 and 6 ( P < 0.05). No F wave was elicited in 41.7% (20/48) of the motor nerves examined at admission, which declined to 25% at 6 months post GBS onset. Decreased amplitude in CMAPs was seen in 50% (24/48) of the motor nerves examined at admission, which decreased to 25% at 6 months ( P < 0.05). Moreover, 60.4% (29/48) of the motor nerves showed abnormal abduction velocity, which declined to 0% at 3 and 6 months post GBS onset ( P < 0.01). In conclusion, GBS patients exhibit a variable course in recovery of electromyographic parameters, and amplitude in CMAPs cannot fully reflect recovery of muscle tone. Conduction block is reversible and in line with rapid muscle tone recovery.

The Role of the Gut Microbiome in Multiple Sclerosis Risk and Progression: Towards Characterization of the "MS Microbiome"

Multiple sclerosis (MS) is the prototypic complex disease, in which both genes and the environment contribute to its pathogenesis. To date, > 200 independent loci across the genome have been associated with MS risk. However, these only explain a fraction of the total phenotypic variance, suggesting the possible presence of additional genetic factors, and, most likely, also environmental factors. New DNA sequencing technologies have enabled the sequencing of all kinds of microorganisms, including those living in and around humans (i.e., microbiomes). The study of bacterial populations inhabiting the gut is of particular interest in autoimmune diseases owing to their key role in shaping immune responses. In this review, we address the potential crosstalk between B cells and the gut microbiota, a relevant scenario in light of recently approved anti-B-cell therapies for MS. In addition, we review recent efforts to characterize the gut microbiome in patients with MS and discuss potential challenges and future opportunities. Finally, we describe the international MS microbiome study, a multicenter effort to study a large population of patients with MS and their healthy household partners to define the core MS microbiome, how it is shaped by disease-modifying therapies, and to explore potential therapeutic interventions.

Effect of serum inflammatory markers on the prognosis of adult and pediatric patients with Guillain-Barré syndrome

OBJECTIVE

The aim of this study was to evaluate blood neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), C-reactive protein (CRP), and albumin levels for their prognostic value in adult Guillain-Barré syndrome (GBS-A) and pediatric Guillain-Barré syndrome (GBS-P) patients.

PATIENTS AND METHODS

We retrospectively analyzed the medical records of 68 Guillain-Barré syndrome (GBS) patients (36 adults, 32 children) who were treated as inpatients at Harran University Faculty of Medicine, Neurology and Pediatric Neurology Departments. The pretreatment NLR, PLR, CRP, and albumin levels and Hughes scores at hospital admission, discharge, and third-month control were documented.

RESULTS

In GBS-A patients, the mean CRP and NLR levels at admission/discharge and third-month control were significantly higher, and the mean albumin level was significantly lower in the Hughes disability scale (HDS)≥3 group. In GBS-P group, the mean NLR level at third month was significantly higher in the HDS≥3 group. GBS-A patients had higher mean NLR, PLR, and CRP levels and lower mean albumin values than GBS-P patients. Both GBS-A and GBS-P patients had higher mean NLR, PLR, and CRP levels and lower mean albumin values than healthy controls. Only the albumin level of the GBS-A group was found to be a significant predictor of prognosis at discharge from hospital.

CONCLUSION

NLR, CRP, and albumin levels in the GBS-A group and NLR levels in the GBS-P group may be helpful in predicting the prognosis of the disease. The albumin level of GBS-A patients is an independent risk factor for prognosis at discharge from hospital.

Diseases of the peripheral nerves

This chapter reviews the diseases of the peripheral nerves from a neuropathologic point of view, with a special focus on specific morphologic changes, and includes a summary of the histopathologic methods available for their diagnosis. As the rate of obesity and the prevalence of type 2 diabetes increase, diabetic neuropathy is the most common cause of peripheral neuropathy. Many systemic disorders with metabolic origin, like amyloidosis, hepatic failure, vitamin deficiencies, uremia, lipid metabolism disorders, and others, can also cause axonal or myelin alterations in the peripheral nervous system. The most notable causes of toxic neuropathies are chemotherapeutic agents, alcohol consumption, and exposure to heavy metals and other environmental or biologic toxins. Inflammatory neuropathies cover infectious neuropathies (Lyme disease, human immunodeficiency virus, leprosy, hepatitis) and neuropathies of autoimmune origin (sarcoidosis, Guillain-Barré syndrome/acute inflammatory demyelinating polyneuropathy, chronic inflammatory demyelinating polyneuropathy, and diverse forms of vasculitis. The increasing number of known diseases causing gene mutations in hereditary peripheral neuropathies requires precise characterization, which includes histopathology.

A rating scale for the severity of Guillain-Barré syndrome

INTRODUCTION

The objective of this study was to develop a rating scale to assess the severity of Guillain-Barré syndrome (GBS).

METHODS

The preliminary rating scale, which contained 11 items, was developed by the Delphi method, and data of 258 patients were collected to evaluate it. Item analysis was accomplished by 100 patients; the additional 158 patients were used to evaluate the reliability, validity, and discriminative ability of the rating scale. The structure of the rating scale was testified by the confirmatory factor analysis and also made a further evaluation by the correlation analysis.

RESULTS

The rating scale contained 10 items. The three factors mainly generalized the motor function, cranial nerve function and autonomic function. The results of reliability and validity showed that the structure of the rating scale was good (χ² =68.25, df=32, χ² /df=2.13, normed fit index (NFI)=0.919, non-normed fit index (NNFI)=0.936, comparative fit index (CFI)=0.96, a root mean square error of approximation (RMSEA)=0.085), and the Cronbach's α coefficient for the scale was .852, with the three dimensions ranging from .585 to .752.

CONCLUSION

Reliability and validity of the rating scale are all satisfied. The scale contained the main clinical presentations of GBS, and it is suitable to evaluate the severity of GBS.

Zika Virus-associated Ocular and Neurologic Disorders: The Emergence of New Evidence

BACKGROUND

It has been approximately 70 years since the discovery of the Zika virus (ZIKV). It had been established that the virus causes mild infections and is confined to Africa and Asia; however, major changes in the clinical and epidemiologic patterns of ZIKV infection have occurred in recent years. The virus has attracted intense interest because of the possible association of several autoimmune and neurodevelopmental disorders.

METHODS

We present a summary of the articles that attempt to explain the ZIKV unknowns and strengthen the association with some disorders that are thought to be related to ZIKV, by describing the discovery milestones from the initial identification of the virus to the present day.

RESULTS

New evidence strengthens the association between ZIKV infections and Guillain-Barré syndrome (GBS), microcephaly and various neurodevelopmental and ophthalmologic disorders as a result of numerous new clinical and experimental studies.

CONCLUSIONS

The World Health Organization declared the end of the "Public Health Emergency of International Concern" in December 2016, but ZIKV and associated consequences remain a significant enduring public health challenge.

Novel pathomechanisms in inflammatory neuropathies

Inflammatory neuropathies are rare autoimmune-mediated disorders affecting the peripheral nervous system. Considerable progress has recently been made in understanding pathomechanisms of these disorders which will be essential for developing novel diagnostic and therapeutic strategies in the future. Here, we summarize our current understanding of antigenic targets and the relevance of new immunological concepts for inflammatory neuropathies. In addition, we provide an overview of available animal models of acute and chronic variants and how new diagnostic tools such as magnetic resonance imaging and novel therapeutic candidates will benefit patients with inflammatory neuropathies in the future. This review thus illustrates the gap between pre-clinical and clinical findings and aims to outline future directions of development.

Behavioral, climatic, and environmental risk factors for Zika and Chikungunya virus infections in Rio de Janeiro, Brazil, 2015-16

The burden of arboviruses in the Americas is high and may result in long-term sequelae with infants disabled by Zika virus infection (ZIKV) and arthritis caused by infection with Chikungunya virus (CHIKV). We aimed to identify environmental drivers of arbovirus epidemics to predict where the next epidemics will occur and prioritize municipalities for vector control and eventual vaccination. We screened sera and urine samples (n = 10,459) from residents of 48 municipalities in the state of Rio de Janeiro for CHIKV, dengue virus (DENV), and ZIKV by molecular PCR diagnostics. Further, we assessed the spatial pattern of arbovirus incidence at the municipal and neighborhood scales and the timing of epidemics and major rainfall events. Lab-confirmed cases included 1,717 infections with ZIKV (43.8%) and 2,170 with CHIKV (55.4%) and only 29 (<1%) with DENV. ZIKV incidence was greater in neighborhoods with little access to municipal water infrastructure (r = -0.47, p = 1.2x10^-8). CHIKV incidence was weakly correlated with urbanization (r = 0.2, p = 0.02). Rains began in October 2015 and were followed one month later by the largest wave of ZIKV epidemic. ZIKV cases markedly declined in February 2016, which coincided with the start of a CHIKV outbreak. Rainfall predicted ZIKV and CHIKV with a lead time of 3 weeks each time. The association between rainfall and epidemics reflects vector ecology as the larval stages of Aedes aegypti require pools of water to develop. The temporal dynamics of ZIKV and CHIKV may be explained by the shorter incubation period of the viruses in the mosquito vector; 2 days for CHIKV versus 10 days for ZIKV.

Spinal nerve involvement in early Guillain-Barré syndrome: The Haymaker and Kernohan's legacy

Pathological studies of early Guillain-Barré syndrome (GBS), defined as of 10days of disease onset, are scanty making it difficult to interpret the physiopathology of clinical and electrophysiological features. In 1949, Webb Haymaker and James Kernohan reported 50 clinico-pathological studies of fatal GBS cases, 32 of them having died between days 2 and 10 after onset. They established that the brunt of initial lesions, consisting of endoneurial oedema interpreted as degenerative, relied on spinal nerves. That this oedema was inflammatory was soon thereafter recognized. Two decades later, however, the pathogenic role of endoneurial oedema was disputed. In experimental allergic neuritis, considered an animal model of GBS, the initial lesion appearing on day 4 post-inoculation is marked inflammatory oedema in the sciatic nerve and lumbosacral nerve roots. Additional detailed clinico-pathological studies corroborated that the appearance of epi-perineurium at the subarachnoid angle, where anterior and posterior roots join to form the spinal nerve, is a pathological hotspot in early GBS, there developing inflammatory oedema, incipient demyelination and endoneurial ischemic zones with axonal degeneration. Furthermore, nerve ultrasonography has demonstrated predominant spinal nerve changes in early GBS, either demyelinating or axonal. Other outstanding Haymaker and Kernohan's contributions were to clarify the complex nosology of the syndrome bringing under the same rubric Landry's paralysis, acute febrile polyneuritis and GBS, and critically analyzing GBS exclusion criteria by then prevailing. It is concluded that the authors' legacy remains as relevant as ever.

Is serum bilirubin associated with the severity of Guillain-Barré syndrome?

OBJECTIVE

Our aim was to assess the correlation between serum bilirubin levels and Guillain-Barré syndrome (GBS).

PATIENTS AND METHODS

One hundred and one newly diagnosed patients with Guillain-Barré syndrome and 111 healthy age- and sex-matched individuals in the First Affiliated Hospital of Guangxi Medical University (Guangxi, China) from June 2012 to May 2017 were included in this study. Clinical characteristics and laboratory parameters of Guillain-Barré syndrome patients and healthy controls were retrospectively analysed.

RESULTS

Serum bilirubin levels in Guillain-Barré syndrome patients were significantly lower as compared with those in healthy controls (p < 0.001); besides, log C-reactive protein and erythrocyte sedimentation rate were significantly higher. We found that there was a negative correlation between GBS disability scale scores and total bilirubin, direct bilirubin, indirect bilirubin (r = -0.541, P < 0.001; r = -0.403, P < 0.001; r = -0.526, P < 0.001), respectively. Among patients with GBS, serum total bilirubin, direct bilirubin, and indirect bilirubin levels were independently associated with Guillain-Barré syndrome disability scale scores in multiple linear regression analysis, respectively.

CONCLUSIONS

We observed that serum bilirubin levels were lower in patients with Guillain-Barré syndrome, and suggested total bilirubin, direct bilirubin, and indirect bilirubin were independently and inversely associated with Guillain-Barré syndrome severity.