Christa Walgaard

Guillain-Barré syndrome: pathogenesis, diagnosis, treatment and prognosis.

Guillain–Barré syndrome (GBS) is a potentially life-threatening postinfectious disease characterized by rapidly progressive, symmetrical weakness of the extremities. About 25% of patients develop respiratory insufficiency and many show signs of autonomic dysfunction. Diagnosis can usually be made on clinical grounds, but lumbar puncture and electrophysiological studies can help to substantiate the diagnosis and to differentiate demyelinating from axonal subtypes of GBS. Molecular mimicry of pathogen-borne antigens, leading to generation of crossreactive antibodies that also target gangliosides, is part of the pathogenesis of GBS; the subtype and severity of the syndrome are partly determined by the nature of the antecedent infection and specificity of such antibodies. Intravenous immunoglobulin and plasma exchange are proven effective treatments but many patients have considerable residual deficits. Discrimination of patients with treatment-related fluctuations from those with acute-onset chronic inflammatory demyelinating polyneuropathy is important, as these conditions may require different treatments. Novel prognostic models can accurately predict outcome and the need for artificial ventilation, which could aid the selection of patients with a poor prognosis for more-individualized care. This Review summarizes the clinical features of and diagnostic criteria for GBS, and discusses its pathogenesis, treatment and prognosis.

Diagnosis of Guillain-Barre syndrome and validation of Brighton criteria

Guillain-Barré syndrome is an acute polyradiculoneuropathy with a variable clinical presentation. Accurate diagnostic criteria are essential for patient care and research, including clinical trials and vaccine safety studies. Several diagnostic criteria for Guillain-Barré syndrome have been proposed, including the recent set by the Brighton Collaboration. In the present study we describe in detail the key diagnostic features required to meet these Brighton criteria in a study population of 494 adult patients with Guillain-Barré syndrome, previously included in therapeutic and observational studies. The patients had a median age of 53 years (interquartile range 36-66 years) and males slightly predominated (56%). All patients developed bilateral limb weakness which generally involved both upper and lower extremities. The weakness remained restricted to the legs in 6% and to the arms in 1% of the patients. Decreased reflexes in paretic arms or legs were found initially in 91% of patients and in all patients during follow-up. Ten (2%) patients however showed persistence of normal reflexes in paretic arms. Disease nadir was reached within 2 weeks in 80%, within 4 weeks in 97% and within 6 weeks in all patients. A monophasic disease course occurred in 95% of patients, of whom 10% had a treatment-related fluctuation. A clinical deterioration after 8 weeks of onset of weakness occurred in 23 (5%) patients. Cerebrospinal fluid was examined in 474 (96%) patients. A mild pleocytosis (5 to 50 cells/μl) was found in 15%, and none had more than 50 cells/μl. An increased cerebrospinal fluid protein concentration was found only in 64% of patients, highly dependent on the timing of the lumbar puncture after onset of weakness (49% at the first day to 88% after 2 weeks). Nerve electrophysiology was compatible with the presence of a neuropathy in 99% of patients, but only 59% fulfilled the current criteria for a distinct subtype of Guillain-Barré syndrome. Patients with a complete data set (335) were classified according to the Brighton criteria, ranging from a high to a low level of diagnostic certainty, as level 1 in 61%, level 2 in 33%, level 3 in none, and level 4 in 6% of patients. Patients categorized in these levels did not differ with respect to proportion of patients with preceding events, initial clinical manifestations or outcome. The observed variability in the key diagnostic features of Guillain-Barré syndrome in the current cohort study, can be used to improve the sensitivity of the diagnostic criteria.

Early recognition of poor prognosis in Guillain-Barré syndrome

Background: Guillain-Barré syndrome (GBS) has a highly diverse clinical course and outcome, yet patients are treated with a standard therapy. Patients with poor prognosis may benefit from additional treatment, provided they can be identified early, when nerve degeneration is potentially reversible and treatment is most effective. We developed a clinical prognostic model for early prediction of outcome in GBS, applicable for clinical practice and future therapeutic trials. Methods: Data collected prospectively from a derivation cohort of 397 patients with GBS were used to identify risk factors of being unable to walk at 4 weeks, 3 months, and 6 months. Potential predictors of poor outcome (unable to walk unaided) were considered in univariable and multivariable logistic regression models. The clinical model was based on the multivariable logistic regression coefficients of selected predictors and externally validated in an independent cohort of 158 patients with GBS. Results: High age, preceding diarrhea, and low Medical Research Council sumscore at hospital admission and at 1 week were independently associated with being unable to walk at 4 weeks, 3 months, and 6 months (all p 0.05–0.001). The model can be used at hospital admission and at day 7 of admission, the latter having a better predictive ability for the 3 endpoints; the area under the receiver operating characteristic curve (AUC) is 0.84–0.87 and at admission the AUC is 0.73–0.77. The model proved to be valid in the validation cohort. Conclusions: A clinical prediction model applicable early in the course of disease accurately predicts the first 6 months outcome in GBS.

Prediction of respiratory insufficiency in Guillain-Barré syndrome

Respiratory insufficiency is a frequent and serious complication of the Guillain‐Barré syndrome (GBS). We aimed to develop a simple but accurate model to predict the chance of respiratory insufficiency in the acute stage of the disease based on clinical characteristics available at hospital admission.

Antibodies to Heteromeric Glycolipid Complexes in Guillain-Barré Syndrome

Autoantibodies are infrequently detected in the sera of patients with the demyelinating form of Guillain-Barré syndrome most commonly encountered in the Western world, despite abundant circumstantial evidence suggesting their existence. We hypothesised that antibody specificities reliant on the cis interactions of neighbouring membrane glycolipids could explain this discrepancy, and would not have been detected by traditional serological assays using highly purified preparations of single gangliosides. To assess the frequency of glycolipid complex antibodies in a Western European cohort of patients GBS we used a newly developed combinatorial glycoarray methodology to screen against large range of antigens (11 gangliosides, 8 other single glycolipids and 162 heterodimeric glycolipid complexes). Serum samples of 181 patients from a geographically defined, Western European cohort of GBS cases were analysed, along with 161 control sera. Serum IgG binding to single gangliosides was observed in 80.0% of axonal GBS cases, but in only 11.8% of cases with demyelinating electrophysiology. The inclusion of glycolipid complexes increased the positivity rate in demyelinating disease to 62.4%. There were 40 antigens with statistically significantly increased binding intensities in GBS as compared to healthy control sera. Of these, 7 complex antigens and 1 single ganglioside also produced statistically significantly increased binding intensities in GBS versus neurological disease controls. The detection of antibodies against specific complexes was associated with particular clinical features including disease severity, requirement for mechanical ventilation, and axonal electrophysiology. This study demonstrates that while antibodies against single gangliosides are often found in cases with axonal-type electrophysiology, antibodies against glycolipid complexes predominate in cases with demyelinating electrophysiology, providing a more robust serum biomarker than has ever been previously available for such cases. This work confirms the activation of the humoral immune system in the dysimmune disease process in GBS, and correlates patterns of antigen recognition with different clinical features.

Emerging drugs for Guillain-Barré syndrome

Introduction: Intravenous immunoglobulin (IVIg) and plasma exchange are proven effective treatments for Guillain-Barré syndrome (GBS). However, this treatment is insufficient for many patients as 1 – 5% die, 25% need artificial respiration, 20% are still unable to walk unaided after 6 months and 85% have residual symptoms, such as fatigue and pain. Areas covered: Strategies to design and conduct trials with new compounds and individualized regimens of IVIg are discussed. The development of specific immunomodulators is set against a background of recent insights in the pathophysiological mechanisms of GBS. Patients with poor prognosis can be identified in the early phase of disease using predictors such as high age, severe disability, preceding diarrhea and possibly low increase in serum IgG after standard IVIg treatment. An ongoing trial with a second IVIg dose in this group and the preclinical development of potential new treatments and their mode of action are discussed. Expert opinion: GBS is a heterogeneous disease with considerable short- and long-term disability for which more effective and individualized treatments are required. Under investigation are new treatment strategies with adapted IVIg dosages based on prognostic factors and more specific immunomodulation, including complement inhibitors.

Association of Albumin Levels With Outcome in Intravenous Immunoglobulin–Treated Guillain-Barré Syndrome

Importance There is an urgent need for biomarkers to monitor treatment efficacy and anticipate outcome in patients with Guillain-Barré syndrome (GBS). Objective To assess whether there is an association between serum albumin levels, a widely used and relatively easily measurable biomarker of health and inflammation, and the clinical course and outcome of GBS in patients treated with intravenous immunoglobulin (IVIG). Design, Setting, and Participants We used serum samples derived from a cohort of patients with GBS admitted to hospitals across the Netherlands participating in national GBS studies from May 5, 1986, through August 2, 2000. Serum albumin was measured from January 13 to 20, 2011. Analysis was performed from February 25, 2013, to September 6, 2016. All patients fulfilled the criteria for GBS and had severe disease (defined as not being able to walk unaided >10 m). Patients misdiagnosed as having GBS were retrospectively excluded from the study. Serum samples were obtained before and after IVIG treatment at 4 standardized time points from 174 patients. Albumin levels were determined by routine diagnostic turbidimetry and related to demographics and clinical course during a follow-up of 6 months. Main Outcomes and Measures Serum albumin concentration was determined before and after treatment with IVIG and related to clinical outcome: muscle weakness (measured by Medical Research Council sum score), respiratory failure (measured by requirement and duration of mechanical ventilation), and ability to walk (measured by GBS disability score). Results Serum albumin levels were determined in 174 patients with GBS (mean [SD] age, 49.6 [20.1] years; 99 males [56.9%]). Before treatment, the median serum albumin level was 4.2 g/dL (interquartile range, 3.8-4.5 g/dL), with hypoalbuminemia (albumin, <3.5 g/dL) in 20 (12.8%) of 156 patients. Two weeks after commencing treatment with IVIG (2 g/kg), the median serum albumin level decreased to 3.7 g/dL (interquartile range, 3.2-4.1 g/dL) (P < .001), and the number with hypoalbuminemia increased to 60 (34.5%) of 174 (P < .001). Hypoalbuminemia was associated with an increased chance of respiratory failure before (16 [36.4%] of 44, P = .001) or after (29 [54.7%] of 53, P < .001) IVIG treatment, inability to walk unaided (21 [35.0%] of 60 vs 6 [5.3%] of 114, P < .001), and severe muscle weakness at 4 weeks (Medical Research Council sum score, 31.8 vs 52.9, P < .001) and 6 months (Medical Research Council sum score, 49.4 vs 58.4, P < .001). Conclusions and Relevance Patients with GBS may develop hypoalbuminemia after treatment with IVIG, which is related to a more severe clinical course and a poorer outcome. Further studies are required to confirm that serum albumin can be used as a biomarker to monitor disease activity and treatment response to IVIG in patients with GBS.

Second IVIg course in Guillain-Barré syndrome patients with poor prognosis (SID-GBS trial): Protocol for a double-blind randomized, placebo-controlled clinical trial

One course of intravenous immunoglobulins (IVIg) of 2 g/kg is standard treatment in Guillain‐Barré syndrome (GBS) patients unable to walk independently. Despite treatment some patients recover poorly, in part related to rapid consumption of IVIg, indicating that they may benefit from a second course of IVIg. The aim of the study is to determine whether a second course of IVIg, administered 1 week after start of the first course in patients with GBS and predicted poor outcome improves functional outcome on the GBS disability scale after 4 weeks. Secondary outcome measures include adverse events (AEs), Medical Research Council sumscore and GBS disability score after 8, 12, and 26 weeks, length of hospital and ICU admission, mortality, and changes in serum IgG levels. GBS patients of 12 years and older with a poor prognosis, based on the modified Erasmus GBS outcome score (mEGOS) at 1 week after start of the first IVIg course are eligible for randomization in this double‐blind, placebo‐controlled (IVIg or albumin) clinical trial. This study will determine if a second course of IVIg administered in the acute phase of the disease is safe, feasible, and effective in patients with GBS and a poor prognosis. This Dutch trial is registered prospectively as NTR 2224 in the Netherlands National Trial Register (NTR) which is the Primary Registry in the WHO Registry Network for the Netherlands.