167 research outputs found
The Cerebrospinal Fluid in Multiple Sclerosis
Investigation of cerebrospinal fluid (CSF) in the diagnostic work-up in suspected multiple sclerosis (MS) patients has regained attention in the latest version of the diagnostic criteria due to its good diagnostic accuracy and increasing issues with misdiagnosis of MS based on over interpretation of neuroimaging results. The hallmark of MS-specific changes in CSF is the detection of oligoclonal bands (OCB) which occur in the vast majority of MS patients. Lack of OCB has a very high negative predictive value indicating a red flag during the diagnostic work-up, and alternative diagnoses should be considered in such patients. Additional molecules of CSF can help to support the diagnosis of MS, improve the differential diagnosis of MS subtypes and predict the course of the disease, thus selecting the optimal therapy for each patient
Nodding syndrome in Tanzania may not be associated with circulating anti-NMDA- and anti-VGKC receptor antibodies or decreased pyridoxal phosphate serum levels-a pilot study
Background: Nodding syndrome (NS) is a seemingly progressive epilepsy disorder of unknown underlying cause. We investigated association of pyridoxal-phosphate serum levels and occurrence of anti-neuronal antibodies against N-methyl-D-aspartate (NMDA) receptor and voltage gated potassium channel (VGKC) complex in NS patients.Methods: Sera of a Tanzanian cohort of epilepsy and NS patients and community controls were tested for the presence of anti-NMDA-receptor and anti-VGKC complex antibodies by indirect immunofluorescence assay. Furthermore pyridoxal-phosphate levels were measured.Results: Auto-antibodies against NMDA receptor or VGKC (LG1 or Caspr2) complex were not detected in sera of patients suffering from NS (n=6), NS plus other seizure types (n=16), primary generalized epilepsy (n=1) and community controls without epilepsy (n=7). Median Pyridoxal-phosphate levels in patients with NS compared to patients with primary generalized seizures and community controls were not significantly different. However, these median pyridoxal-phosphate levels are significantly lower compared to the range considered normal in Europeans.Conclusions: In this pilot study NS was not associated with serum anti-NMDA receptor or anti-VGKC complex antibodies and no association to pyridoxal-phosphate serum levels was found.Key words: nodding syndrome, epilepsy, anti-neuronal antibodies, pyridoxal-phosphat
Psychometrische Prüfung des deutschsprachigen „Neurologischen Fragebogens zur Müdigkeit bei Multipler Sklerose (NFI-MS-G)“ bei Rehabilitanden mit Multipler Sklerose (Psychometric Evaluation of the ‘German Neurological Fatigue Index for Multiple Sclerosis (NFI-MS-G)’ in a Sample of Rehabilitation Patients with Multiple Sclerosis)
Purpose The purpose of this study was to provide a patient-reported outcome measure for people with multiple sclerosis (MS) comprehensively reflecting the construct of fatigue and developed upon the assumptions of the Rasch model. The Neurological Fatigue Index – Multiple Sclerosis (NFI-MS) is based on both a medical and patient-described symptom framework of fatigue and has been validated. Therefore, in this study the German version of the NFI-MS (NFI-MS-G) consisting of a physical and cognitive subscale and a summary scale was validated.
Method In this bi-centre-study, 309 people with MS undergoing outpatient rehabilitation or being≥2 months before or after their inpatient rehabilitation completed the German NFI-MS-G twice within 14–21 days together with other questionnaires. Correlation with established questionnaires and Rasch analysis were used for its validation. Additionally, psychometric properties of known-groups validity, internal consistency, test-retest reliability, measurement precision and readability were tested. Finally, the English NFI-MS and German NFI-MS-G were compared with each other to equate the language versions.
Results The NFI-MS-G showed good internal construct validity, convergent and known-groups validity and internal consistency (Cronbach’s alpha 0.84–0.93). The physical subscale showed minor local dependencies between items 1 and 7, 2 and 3 and 4 to 6, that could be treated by combining the respective items to testlets. Unidimensionality was found for the physical and cognitive subscales but not for the summary scale. Replacing the summary scale, a 2-domains subtest measuring the higher-order construct of fatigue was created. Good test-retest reliability (Lin’s concordance correlation coefficient of 0.86–0.90) and low floor and ceiling effects were demonstrated. The NFI-MS-G was found easily readable and invariant across groups of gender, age, disease duration, timepoint and centre.
Conclusion The German version of the NFI-MS comprehensively represents the construct of fatigue and has adequate psychometric properties. The German version differs from the English original version with respect to a lack of unidimensionality of the summary scale and minor local dependencies of the physical subscale that could be canceled out using a testlet analysis
IgG-index predicts neurological morbidity in patients with infectious central nervous system diseases
<p>Abstract</p> <p>Background</p> <p>Prognosis assessment of patients with infectious and neoplastic disorders of the central nervous system (CNS) may still pose a challenge. In this retrospective cross-sectional study the prognostic value of basic cerebrospinal fluid (CSF) parameters in patients with bacterial meningitis, viral meningoencephalitis and leptomeningeal metastases were evaluated.</p> <p>Methods</p> <p>White blood cell count, CSF/serum glucose ratio, protein, CSF/serum albumin quotient and Immunoglobulin indices for IgG, IgA and IgM were analyzed in 90 patients with bacterial meningitis, 117 patients with viral meningoencephalitis and 36 patients with leptomeningeal metastases in a total of 480 CSF samples.</p> <p>Results</p> <p>In the initial spinal tap, the IgG-index was the only independent predictor for unfavorable outcome (GOS < 5) in patients with infectious CNS diseases but not in patients with leptomeningeal metastases. The sensitivity and specificity of an IgG-index of 0.75 and higher for predicting unfavorable outcome was 40.9% and 80.8% in bacterial meningitis and 40% and 94.8% in viral meningoencephalitis, respectively. No significant associations between CSF parameters and outcome could be observed in follow-up CSF samples.</p> <p>Conclusion</p> <p>The present study suggests that in infectious CNS diseases an elevated IgG-Index might be an additional marker for the early identification of patients at risk for neurological morbidity.</p
Fibrinogen is not elevated in the cerebrospinal fluid of patients with multiple sclerosis
<p>Abstract</p> <p>Background</p> <p>Elevated plasma fibrinogen levels are a well known finding in acute infectious diseases, acute stroke and myocardial infarction. However its role in the cerebrospinal fluid (CSF) of acute and chronic central (CNS) and peripheral nervous system (PNS) diseases is unclear.</p> <p>Findings</p> <p>We analyzed CSF and plasma fibrinogen levels together with routine parameters in patients with multiple sclerosis (MS), acute inflammatory diseases of the CNS (bacterial and viral meningoencephalitis, BM and VM) and PNS (Guillain-Barré syndrome; GBS), as well as in non-inflammatory neurological controls (OND) in a total of 103 patients. Additionally, MS patients underwent cerebral MRI scans at time of lumbar puncture.</p> <p>CSF and plasma fibrinogen levels were significantly lower in patients with MS and OND patients as compared to patients with BM, VM and GBS. There was a close correlation between fibrinogen levels and albumin quotient (rho = 0.769, <it>p </it>< 0.001) which strongly suggests passive transfer of fibrinogen through the blood-CSF-barrier during acute inflammation. Hence, in MS, the prototype of chronic neuroinflammation, CSF fibrinogen levels were not elevated and could not be correlated to clinical and neuroradiological outcome parameters.</p> <p>Conclusions</p> <p>Although previous work has shown clear evidence of the involvement of fibrinogen in MS pathogenesis, this is not accompanied by increased fibrinogen in the CSF compartment.</p
Search for Specific Biomarkers of IFNβ Bioactivity in Patients with Multiple Sclerosis
Myxovirus A (MxA), a protein encoded by the MX1 gene with antiviral activity, has proven to be a sensitive measure of IFNβ bioactivity in multiple sclerosis (MS). However, the use of MxA as a biomarker of IFNβ bioactivity has been criticized for the lack of evidence of its role on disease pathogenesis and the clinical response to IFNβ. Here, we aimed to identify specific biomarkers of IFNβ bioactivity in order to compare their gene expression induction by type I IFNs with the MxA, and to investigate their potential role in MS pathogenesis. Gene expression microarrays were performed in PBMC from MS patients who developed neutralizing antibodies (NAB) to IFNβ at 12 and/or 24 months of treatment and patients who remained NAB negative. Nine genes followed patterns in gene expression over time similar to the MX1, which was considered the gold standard gene, and were selected for further experiments: IFI6, IFI27, IFI44L, IFIT1, HERC5, LY6E, RSAD2, SIGLEC1, and USP18. In vitro experiments in PBMC from healthy controls revealed specific induction of selected biomarkers by IFNβ but not IFNγ, and several markers, in particular USP18 and HERC5, were shown to be significantly induced at lower IFNβ concentrations and more selective than the MX1 as biomarkers of IFNβ bioactivity. In addition, USP18 expression was deficient in MS patients compared with healthy controls (p = 0.0004). We propose specific biomarkers that may be considered in addition to the MxA to evaluate IFNβ bioactivity, and to further explore their implication in MS pathogenesis
Monocyte NOTCH2 expression predicts interferon-beta immunogenicity in multiple sclerosis patients
Multiple sclerosis (MS) is an autoimmune disease characterized by CNS inflammation leading to demyelination and axonal damage. IFN-β is an established treatment for MS; however, up to 30% of IFN-β–treated MS patients develop neutralizing antidrug antibodies (nADA), leading to reduced drug bioactivity and efficacy. Mechanisms driving antidrug immunogenicity remain uncertain, and reliable biomarkers to predict immunogenicity development are lacking. Using high-throughput flow cytometry, NOTCH2 expression on CD14+ monocytes and increased frequency of proinflammatory monocyte subsets were identified as baseline predictors of nADA development in MS patients treated with IFN-β. The association of this monocyte profile with nADA development was validated in 2 independent cross-sectional MS patient cohorts and a prospective cohort followed before and after IFN-β administration. Reduced monocyte NOTCH2 expression in nADA+ MS patients was associated with NOTCH2 activation measured by increased expression of Notch-responsive genes, polarization of monocytes toward a nonclassical phenotype, and increased proinflammatory IL-6 production. NOTCH2 activation was T cell dependent and was only triggered in the presence of serum from nADA+ patients. Thus, nADA development was driven by a proinflammatory environment that triggered activation of the NOTCH2 signaling pathway prior to first IFN-β administration
Treatment- and population-specific genetic risk factors for anti-drug antibodies against interferon-beta: a GWAS
BackgroundUpon treatment with biopharmaceuticals, the immune system may produce anti-drug antibodies (ADA) that inhibit the therapy. Up to 40% of multiple sclerosis patients treated with interferon beta (IFN beta) develop ADA, for which a genetic predisposition exists. Here, we present a genome-wide association study on ADA and predict the occurrence of antibodies in multiple sclerosis patients treated with different interferon beta preparations.MethodsWe analyzed a large sample of 2757 genotyped and imputed patients from two cohorts (Sweden and Germany), split between a discovery and a replication dataset. Binding ADA (bADA) levels were measured by capture-ELISA, neutralizing ADA (nADA) titers using a bioassay. Genome-wide association analyses were conducted stratified by cohort and treatment preparation, followed by fixed-effects meta-analysis.ResultsBinding ADA levels and nADA titers were correlated and showed a significant heritability (47% and 50%, respectively). The risk factors differed strongly by treatment preparation: The top-associated and replicated variants for nADA presence were the HLA-associated variants rs77278603 in IFN beta -1a s.c.- (odds ratio (OR)=3.55 (95% confidence interval=2.81-4.48), p=2.1x10(-26)) and rs28366299 in IFN beta -1b s.c.-treated patients (OR=3.56 (2.69-4.72), p=6.6x10(-19)). The rs77278603-correlated HLA haplotype DR15-DQ6 conferred risk specifically for IFN beta -1a s.c. (OR=2.88 (2.29-3.61), p=7.4x10(-20)) while DR3-DQ2 was protective (OR=0.37 (0.27-0.52), p=3.7x10(-09)). The haplotype DR4-DQ3 was the major risk haplotype for IFN beta -1b s.c. (OR=7.35 (4.33-12.47), p=1.5x10(-13)). These haplotypes exhibit large population-specific frequency differences. The best prediction models were achieved for ADA in IFN beta -1a s.c.-treated patients. Here, the prediction in the Swedish cohort showed AUC=0.91 (0.85-0.95), sensitivity=0.78, and specificity=0.90;patients with the top 30% of genetic risk had, compared to patients in the bottom 30%, an OR =73.9 (11.8-463.6, p=4.4x10(-6)) of developing nADA. In the German cohort, the AUC of the same model was 0.83 (0.71-0.92), sensitivity=0.80, specificity=0.76, with an OR=13.8 (3.0-63.3, p=7.5x10(-4)).ConclusionsWe identified several HLA-associated genetic risk factors for ADA against interferon beta, which were specific for treatment preparations and population backgrounds. Genetic prediction models could robustly identify patients at risk for developing ADA and might be used for personalized therapy recommendations and stratified ADA screening in clinical practice. These analyses serve as a roadmap for genetic characterizations of ADA against other biopharmaceutical compounds
Kappa free light chains is a valid tool in the diagnostics of MS: A large multicenter study
Objective: To validate kappa free light chain (KFLC) and lambda free light chain (LFLC) indices as a diagnostic biomarker in multiple sclerosis (MS). Methods: We performed a multicenter study including 745 patients from 18 centers (219 controls and 526 clinically isolated syndrome (CIS)/MS patients) with a known oligoclonal IgG band (OCB) status. KFLC and LFLC were measured in paired cerebrospinal fluid (CSF) and serum samples. Gaussian mix- ture modeling was used to define a cut-off for KFLC and LFLC indexes. Results: The cut-off for the KFLC index was 6.6 (95% confidence interval (CI) = 5.2-138.1). The cut-off for the LFLC index was 6.9 (95% CI=4.5-22.2). For CIS/MS patients, sensitivity of the KFLC index (0.88; 95% CI = 0.85-0.90) was higher than OCB (0.82; 95%CI = 0.79-0.85; p < 0.001), but specificity (0.83; 95% CI = 0.78-0.88) was lower (OCB = 0.92; 95% CI = 0.89-0.96; p < 0.001). Both sensitivity and specificity for the LFLC index were lower than OCB. Conclusion: Compared with OCB, the KFLC index is more sensitive but less specific for diagnosing CIS/MS. Lacking an elevated KFLC index is more powerful for excluding MS compared with OCB but the latter is more important for ruling in a diagnosis of CIS/MS
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