Serum Contactin-1 in CIDP

To investigate whether serum levels of contactin-1, a paranodal protein, correlate with paranodal injury as seen in patients with CIDP with antibodies targeting the paranodal region. Serum contactin-1 levels were measured in 187 patients with CIDP and 222 healthy controls. Paranodal antibodies were investigated in all patients. Serum contactin-1 levels were lower in patients (N = 41) with paranodal antibodies compared with patients (N = 146) without paranodal antibodies (p < 0.01) and showed good discrimination between these groups (area under the curve 0.84; 95% CI: 0.76-0.93). These findings suggest that serum contactin-1 levels have the potential to serve as a possible diagnostic biomarker of paranodal injury in CIDP. This study provides class II evidence that serum contactin-1 levels can discriminate between patients with CIDP with or without paranodal antibodies with a sensitivity of 71% (95% CI: 56%-85%) and a specificity of 97% (95% CI: 83%-100%)

B-cell targeting with anti-CD38 daratumumab:implications for differentiation and memory responses

B cell–targeted therapies, such as CD20-targeting mAbs, deplete B cells but do not target the autoantibody-producing plasma cells (PCs). PC-targeting therapies such as daratumumab (anti-CD38) form an attractive approach to treat PC-mediated diseases. CD38 possesses enzymatic and receptor capabilities, which may impact a range of cellular processes including proliferation and differentiation. However, very little is known whether and how CD38 targeting affects B-cell differentiation, in particular for humans beyond cancer settings. Using in-depth in vitro B-cell differentiation assays and signaling pathway analysis, we show that CD38 targeting with daratumumab demonstrated a significant decrease in proliferation, differentiation, and IgG production upon T cell–dependent B-cell stimulation. We found no effect on T-cell activation or proliferation. Furthermore, we demonstrate that daratumumab attenuated the activation of NF-?B in B cells and the transcription of NF-?B–targeted genes. When culturing sorted B-cell subsets with daratumumab, the switched memory B-cell subset was primarily affected. Overall, these in vitro data elucidate novel non-depleting mechanisms by which daratumumab can disturb humoral immune responses. Affecting memory B cells, daratumumab may be used as a therapeutic approach in B cell–mediated diseases other than the currently targeted malignancies

Second intravenous immunoglobulin dose in patients with Guillain-Barre syndrome with poor prognosis (SID-GBS):a double-blind, randomised, placebo-controlled trial

Background Treatment with one standard dose (2 g/kg) of intravenous immunoglobulin is insufficient in a proportion of patients with severe Guillain-Barre syndrome. Worldwide, around 25% of patients severely affected with the syndrome are given a second intravenous immunoglobulin dose (SID), although it has not been proven effective. We aimed to investigate whether a SID is effective in patients with Guillain-Barre syndrome with a predicted poor outcome. Methods In this randomised, double-blind, placebo-controlled trial (SID-GBS), we included patients (>= 12 years) with Guillain-Barre syndrome admitted to one of 59 participating hospitals in the Netherlands. Patients were included on the first day of standard intravenous immunoglobulin treatment (2 g/kg over 5 days). Only patients with a poor prognosis (score of >= 6) according to the modified Erasmus Guillain-Barre syndrome Outcome Score were randomly assigned, via block randomisation stratified by centre, to SID (2 g/kg over 5 days) or to placebo, 7-9 days after inclusion. Patients, outcome adjudicators, monitors, and the steering committee were masked to treatment allocation. The primary outcome measure was the Guillain-Barre syndrome disability score 4 weeks after inclusion. All patients in whom allocated trial medication was started were included in the modified intention-to-treat analysis. Findings Between Feb 16, 2010, and June 5, 2018, 327 of 339 patients assessed for eligibility were included. 112 had a poor prognosis. Of those, 93 patients with a poor prognosis were included in the modified intention-to-treat analysis: 49 (53%) received SID and 44 (47%) received placebo. The adjusted common odds ratio for improvement on the Guillain-Barre syndrome disability score at 4 weeks was 1.4 (95% CI 0.6-3.3; p=0.45). Patients given SID had more serious adverse events (35% vs 16% in the first 30 days), including thromboembolic events, than those in the placebo group. Four patients died in the intervention group (13-24 weeks after randomisation). Interpretation Our study does not provide evidence that patients with Guillain-Barre syndrome with a poor prognosis benefit from a second intravenous immunoglobulin course; moreover, it entails a risk of serious adverse events. Therefore, a second intravenous immunoglobulin course should not be considered for treatment of Guillain-Barre syndrome because of a poor prognosis. The results indicate the need for treatment trials with other immune modulators in patients severely affected by Guillain-Barre syndrome. Funding Prinses Beatrix Spierfonds and Sanquin Plasma Products. Copyright (C) 2021 Elsevier Ltd. All rights reserved

Genetic correlation between amyotrophic lateral sclerosis and schizophrenia

A. Palotie on työryhmän Schizophrenia Working Grp Psychiat jäsen.We have previously shown higher-than-expected rates of schizophrenia in relatives of patients with amyotrophic lateral sclerosis (ALS), suggesting an aetiological relationship between the diseases. Here, we investigate the genetic relationship between ALS and schizophrenia using genome-wide association study data from over 100,000 unique individuals. Using linkage disequilibrium score regression, we estimate the genetic correlation between ALS and schizophrenia to be 14.3% (7.05-21.6; P = 1 x 10(-4)) with schizophrenia polygenic risk scores explaining up to 0.12% of the variance in ALS (P = 8.4 x 10(-7)). A modest increase in comorbidity of ALS and schizophrenia is expected given these findings (odds ratio 1.08-1.26) but this would require very large studies to observe epidemiologically. We identify five potential novel ALS-associated loci using conditional false discovery rate analysis. It is likely that shared neurobiological mechanisms between these two disorders will engender novel hypotheses in future preclinical and clinical studies.Peer reviewe

Chronic inflammatory demyelinating polyradiculoneuropathy: update on clinical features, phenotypes and treatment options

In this review, we focus on less recognised signs and symptoms in typical chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and on the clinical presentation, course of disease and response to treatment of the atypical CIDP phenotypes. Frequently occurring and often disabling symptoms in CIDP such as fatigue, pain and tremor have recently been emphasised, whereas autonomic dysfunction, if present, is usually mild. Sensory CIDP is probably the most frequent atypical CIDP phenotype and diagnosis can be difficult in the absence of clear demyelinating features on nerve conduction studies. The most important study comparing intravenous immunoglobulin treatment with intravenous methylprednisolone showed a lower rate of discontinuation due to inefficacy, adverse events or intolerance with intravenous immunoglobulin treatment. However, improvement after corticosteroids seems to be more long-lasting than after intravenous immunoglobulin suggesting superior long-term immunosuppressive and immunomodulating effect of corticosteroids in CIDP. Symptoms other than the classical motor and sensory symptoms can lead to significant disability in CIDP patients. Based on limited evidence from largely small retrospective case series, we conclude that atypical CIDP phenotypes often have a different course of disease and sometimes response to treatment when compared with typical CIDP. Prospective multicentre cohort studies using standardised clinical description, electrophysiological parameters and outcome measures are needed to study the natural disease course of these phenotypes including response to different treatment

Immunotherapy of multifocal motor neuropathy

Areas covered: The paper identifies studies since 1985 for patients with MMN. Randomised and non-randomized studies examining the effects of any therapeutic agent were selected, to give a full overview of the different treatments for MMN. The review provides a treatment algorithm together with our views on current treatments, ongoing trials and possible directions for further research. Expert opinion: IVIg remains the only proven treatment for MMN, although questions around dosages and duration of treatment remain. The presence of an effective therapy for MMN should not discourage but stimulate further research into alternative treatments as ongoing axonal damage results in increasing impairment in patients with MM

Intravenous immunoglobulin treatment in chronic inflammatory demyelinating polyradiculoneuropathy, a time to start and a time to stop

Intravenous immunoglobulin (IVIg) is often used as preferred treatment in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Several studies highlighted the short-term efficacy of IVIg for CIDP yet many patients need maintenance therapy. Notwithstanding the fact IVIg has been used for over 30 years in CIDP, there is only limited evidence to guide dosage and interval during maintenance treatment. The variation in disease course, lack of biomarkers, and fear of deterioration after stopping IVIg makes long-term treatment challenging. Recent studies suggest a proportion of patients receive unnecessary IVIg maintenance treatment. This review provides an overview of the use of IVIg for CIDP treatment, focusing on evidence for long-term IVIg us