Oligoclonal IgG bands in cerebrospinal fluid in various neurological diseases

Oligoclonal bands

Oligoclonal bands (OCBs) represent the presence of intrathecal immunoglobulin G (IgG) as detected by isoelectric focusing and immunofixation. Cerebrospinal fluid (CSF) analysed alongside a paired serum sample gives five different immunofixation patterns. These are: type 1-the normal physiological state with no intrathecal IgG synthesis; type 2-evidence for intrathecal IgG synthesis, with CSF-restricted OCBs; type 3-evidence for intrathecal IgG synthesis, with CSF-restricted OCBs, but with additional, identical bands in the CSF and serum; type 4-absence of intrathecal IgG synthesis, but with identical OCBs in CSF and serum; and type 5-absence of intrathecal IgG synthesis, with a monoclonal band in CSF and serum. Analysis of these patterns can help to diagnose a range of neurological conditions, including multiple sclerosis. However, it is important to interpret OCB results alongside other CSF tests and their clinical context.

Body fluid markers for multiple sclerosis and differential diagnosis from atypical demyelinating disorders

INTRODUCTION

Body fluid markers could be helpful to predict the conversion into clinically definite multiple sclerosis (MS) in people with a first demyelinating event of the central nervous system (CNS). Consequently, biomarkers such as oligoclonal bands, which are integrated in the current MS diagnostic criteria, could assist early MS diagnosis.

AREAS COVERED

This review examines existing knowledge on a broad spectrum of body fluid markers in people with a first CNS demyelinating event, explores their potential to predict conversion to MS, to assess MS disease activity, as well as their utility to differentiate MS from atypical demyelinating disorders such as neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein associated disease.

EXPERT OPINION

This field of research has shown a dramatic increase of evidence, especially in the last decade. Some biomarkers are already established in clinical routine (e.g. oligoclonal bands) while others are currently implemented (e.g. kappa free light chains) or considered as breakthroughs (e.g. neurofilament light). Determination of biomarkers poses challenges for continuous monitoring, especially if exclusively detectable in cerebrospinal fluid. A handful of biomarkers are measurable in blood which holds a significant potential.

The Heterogeneous Multiple Sclerosis Lesion: How Can We Assess and Modify a Degenerating Lesion?

Multiple sclerosis (MS) is a heterogeneous disease of the central nervous system that is governed by neural tissue loss and dystrophy during its progressive phase, with complex reactive pathological cellular changes. The immune-mediated mechanisms that promulgate the demyelinating lesions during relapses of acute episodes are not characteristic of chronic lesions during progressive MS. This has limited our capacity to target the disease effectively as it evolves within the central nervous system white and gray matter, thereby leaving neurologists without effective options to manage individuals as they transition to a secondary progressive phase. The current review highlights the molecular and cellular sequelae that have been identified as cooperating with and/or contributing to neurodegeneration that characterizes individuals with progressive forms of MS. We emphasize the need for appropriate monitoring via known and novel molecular and imaging biomarkers that can accurately detect and predict progression for the purposes of newly designed clinical trials that can demonstrate the efficacy of neuroprotection and potentially neurorepair. To achieve neurorepair, we focus on the modifications required in the reactive cellular and extracellular milieu in order to enable endogenous cell growth as well as transplanted cells that can integrate and/or renew the degenerative MS plaque.

Clinical associations and characteristics of the polyspecific intrathecal immune response in elderly patients with non-multiple sclerosis chronic autoimmune-inflammatory neurological diseases - a retrospective cross-sectional study

Introduction

The polyspecific intrathecal immune response (PSIIR), aka MRZ reaction (M = measles, R = rubella, Z = zoster, optionally Herpes simplex virus, HSV) is defined as intrathecal immunoglobulin synthesis (IIS) for two or more unrelated viruses. Although an established cerebrospinal fluid (CSF) biomarker for multiple sclerosis (MS), a chronic autoimmune-inflammatory neurological disease (CAIND) of the central nervous system (CNS) usually starting in young adulthood, the full spectrum of CAINDs with a positive PSIIR remains ill defined.

Methods

In this retrospective, cross-sectional study, patients with CSF-positive oligoclonal bands (OCB) and - to enrich for non-MS diagnoses - aged ≥50 years were enrolled.

Results

Of 415 with PSIIR testing results (MRZ, HSV optional), 76 were PSIIR-positive. Of these, 25 (33%) did not meet the diagnostic criteria for MS spectrum diseases (MS-S) comprising clinically or radiologically isolated syndrome (CIS/RIS) or MS. PSIIR-positive non-MS-S phenotypes were heterogenous with CNS, peripheral nerve and motor neuron involvement and often defied unequivocal diagnostic classification. A rating by neuroimmunology experts suggested non-MS CAINDs in 16/25 (64%). Long-term follow-up available in 13 always showed a chronically progressive course. Four of five responded to immunotherapy. Compared to MS-S patients, non-MS CAIND patients showed less frequent CNS regions with demyelination (25% vs. 75%) and quantitative IgG IIS (31% vs. 81%). MRZ-specific IIS did not differ between both groups, while additional HSV-specific IIS was characteristic for non-MS CAIND patients.

Discussion

In conclusion, PSIIR positivity occurs frequently in non-MS-S patients ≥50 years. Although sometimes apparently coincidental, the PSIIR seems to represent a suitable biomarker for previously unnoticed chronic neurologic autoimmunities, which require further characterization.

Molecular biomarkers and cognitive impairment in multiple sclerosis: State of the field, limitations, and future direction - A systematic review and meta-analysis

OBJECTIVE

Multiple sclerosis (MS) is associated with cognitive impairment (CI) such as slowed information processing speed (IPS). Currently, no immunocellular or molecular markers have been established in cerebrospinal fluid and serum analysis as surrogate biomarkers with diagnostic or predictive value for the development of CI. This systematic review and meta-analysis aims to sum up the evidence regarding currently discussed markers for CI in MS.

METHODS

A literature search was conducted on molecular biomarkers of CI in MS, such as neurofilament light chain, chitinases, and vitamin D.

RESULTS

5543 publications were screened, of which 77 entered the systematic review. 13 studies were included in the meta-analysis. Neurofilament light chain (CSF: r_p = -0.294, p = 0.003; serum: r_p = -0.137, p = 0.001) and serum levels of vitamin D (r_p = 0.190, p = 0.014) were associated with IPS outcomes.

CONCLUSIONS

Neurofilament light chain and vitamin D are promising biomarkers to track impairments in IPS in MS. Further longitudinal research is needed to establish the use of molecular biomarkers to monitor cognitive decline.

Assessment of oligoclonal bands in cerebrospinal fluid and serum of dogs with meningoencephalitis of unknown origin

BACKGROUND

Meningoencephalitis of unknown origin (MUO) is an inflammatory disease of the canine central nervous system (CNS) that shares several features with multiple sclerosis (MS) in humans. In approximately 95% of MS patients, ≥ two immunoglobulin G (IgG) oligoclonal bands (OCBs) are detectable exclusively in the cerebrospinal fluid (CSF).

HYPOTHESIS/OBJECTIVES

To investigate OCBs in CSF and serum in dogs affected by MUO, intervertebral disc disease (IVDD), idiopathic epilepsy (IE), intracranial neoplasia (IN), steroid-responsive meningitis-arteritis (SRMA), and diseases outside the CNS. We hypothesize that the highest prevalence of CSF-specific OCBs (≥ two OCBs uniquely in the CSF) would be found in dogs affected by MUO.

ANIMALS

Client-owned dogs (n = 121) presented to the neurology service due to neurological deficits.

METHODS

Prospective study. Measurement of IgG concentration in CSF and serum via a canine IgG ELISA kit. OCB detection via isoelectric focusing (IEF) and immunoblot.

RESULTS

Presence of CSF-specific OCBs was significantly higher in dogs with MUO (57%) compared to 22% in IN, 6% in IE, 15% in SRMA, 13% in IVDD, and 0% in the non-CNS group (p < .001). Dogs with MUO were 9.9 times more likely to show CSF-specific OCBs than all other diseases together (95% confidence interval, 3.7-26.4; p < .001).

CONCLUSIONS AND CLINICAL IMPORTANCE

MUO showed the highest prevalence of CSF-specific OCBs, indicating an inflammatory B cell response. Future studies are needed to evaluate the prevalence in the specific MUO subtypes and a possible similarity with human MS.

Neurodegeneration in multiple sclerosis

Axonal loss in multiple sclerosis (MS) is a key component of disease progression and permanent neurologic disability. MS is a heterogeneous demyelinating and neurodegenerative disease of the central nervous system (CNS) with varying presentation, disease courses, and prognosis. Immunomodulatory therapies reduce the frequency and severity of inflammatory demyelinating events that are a hallmark of MS, but there is minimal therapy to treat progressive disease and there is no cure. Data from patients with MS, post-mortem histological analysis, and animal models of demyelinating disease have elucidated patterns of MS pathogenesis and underlying mechanisms of neurodegeneration. MRI and molecular biomarkers have been proposed to identify predictors of neurodegeneration and risk factors for disease progression. Early signs of axonal dysfunction have come to light including impaired mitochondrial trafficking, structural axonal changes, and synaptic alterations. With sustained inflammation as well as impaired remyelination, axons succumb to degeneration contributing to CNS atrophy and worsening of disease. These studies highlight the role of chronic demyelination in the CNS in perpetuating axonal loss, and the difficulty in promoting remyelination and repair amidst persistent inflammatory insult. Regenerative and neuroprotective strategies are essential to overcome this barrier, with early intervention being critical to rescue axonal integrity and function. The clinical and basic research studies discussed in this review have set the stage for identifying key propagators of neurodegeneration in MS, leading the way for neuroprotective therapeutic development. This article is categorized under: Immune System Diseases > Molecular and Cellular Physiology Neurological Diseases > Molecular and Cellular Physiology.

A Review of Compartmentalised Inflammation and Tertiary Lymphoid Structures in the Pathophysiology of Multiple Sclerosis

Multiple sclerosis (MS) is a chronic, immune-mediated, demyelinating disease of the central nervous system (CNS). The most common form of MS is a relapsing–remitting disease characterised by acute episodes of demyelination associated with the breakdown of the blood–brain barrier (BBB). In the relapsing–remitting phase there is often relative recovery (remission) from relapses characterised clinically by complete or partial resolution of neurological symptoms. In the later and progressive stages of the disease process, accrual of neurological disability occurs in a pathological process independent of acute episodes of demyelination and is accompanied by a trapped or compartmentalised inflammatory response, most notable in the connective tissue spaces of the vasculature and leptomeninges occurring behind an intact BBB. This review focuses on compartmentalised inflammation in MS and in particular, what we know about meningeal tertiary lymphoid structures (TLS; also called B cell follicles) which are organised clusters of immune cells, associated with more severe and progressive forms of MS. Meningeal inflammation and TLS could represent an important fluid or imaging marker of disease activity, whose therapeutic abrogation might be necessary to stop the most severe outcomes of disease.

Determining an infectious or autoimmune etiology in encephalitis

OBJECTIVES

Early presentation and workup for acute infectious (IE) and autoimmune encephalitis (AE) are similar. This study aims to identify routine laboratory markers at presentation that are associated with IE or AE.

METHODS

This was a multi-center retrospective study at three tertiary care hospitals in New York City analyzing demographic and clinical data from patients diagnosed with definitive encephalitis based on a confirmed pathogen and/or autoantibody and established criteria for clinical syndromes.

RESULTS

Three hundred and thirty-three individuals with confirmed acute meningoencephalitis were included. An infectious-nonbacterial (NB) pathogen was identified in 151/333 (45.40%), bacterial pathogen in 95/333 (28.50%), and autoantibody in 87/333 (26.10%). NB encephalitis was differentiated from AE by the presence of fever (NB 62.25%, AE 24.10%; p < 0.001), higher CSF white blood cell (WBC) (median 78 cells/μL, 8.00 cells/μL; p < 0.001), higher CSF protein (76.50 mg/dL, 40.90 mg/dL; p < 0.001), lower CSF glucose (58.00 mg/dL, 69.00 mg/dL; p < 0.001), lower serum WBC (7.80 cells/μL, 9.72 cells/μL; p < 0.050), higher erythrocyte sedimentation rate (19.50 mm/HR, 13.00 mm/HR; p < 0.05), higher C-reactive protein (6.40 mg/L, 1.25 mg/L; p = 0.005), and lack of antinuclear antibody titers (>1:40; NB 11.54%, AE 32.73%; p < 0.001). CSF-to-serum WBC ratio was significantly higher in NB compared to AE (NB 11.3, AE 0.99; p < 0.001). From these findings, the association of presenting with fever, CSF WBC ≥50 cells/μL, and CSF protein ≥75 mg/dL was explored in ruling-out AE. When all three criteria are present, an AE was found to be highly unlikely (sensitivity 92%, specificity 75%, negative predictive value 95%, and positive predictive value 64%).

INTERPRETATIONS

Specific paraclinical data at initial presentation may risk stratify which patients have an IE versus AE.

Kappa Free Light Chains in Cerebrospinal Fluid in Inflammatory and Non-Inflammatory Neurological Diseases

Background: Oligoclonal bands represent intrathecal immunoglobulin G (IgG) synthesis and play an important role in the diagnosis of multiple sclerosis (MS). Kappa free light chains (KFLC) are increasingly recognized as an additional biomarker for intrathecal Ig synthesis. However, there are limited data on KFLC in neurological diseases other than MS. Methods: This study, conducted at two centers, retrospectively enrolled 346 non-MS patients. A total of 182 patients were diagnosed with non-inflammatory and 84 with inflammatory neurological diseases other than MS. A further 80 patients were classified as symptomatic controls. Intrathecal KFLC production was determined using different approaches: KFLC index, Reiber’s diagram, Presslauer’s exponential curve, and Senel’s linear curve. Results: Matching results of oligoclonal bands and KFLC (Reiber’s diagram) were frequently observed (93%). The Reiber’s diagram for KFLC detected intrathecal KFLC synthesis in an additional 7% of the patient samples investigated (4% non-inflammatory; 3% inflammatory), which was not found by oligoclonal band detection. Conclusions: The determination of both biomarkers (KFLC and oligoclonal bands) is recommended for routine diagnosis and differentiation of non-inflammatory and inflammatory neurological diseases. Due to the high sensitivity and physiological considerations, the assessment of KFLC in the Reiber’s diagram should be preferred to other evaluation methods.

Update on Multiple Sclerosis Molecular Biomarkers to Monitor Treatment Effects

Multiple sclerosis (MS) is an inflammatory and neurodegenerative disease of the central nervous system characterized by broad inter- and intraindividual heterogeneity. The relapse rate, disability progression, and lesion load assessed through MRI are used to detect disease activity and response to treatment. Although it is possible to standardize these characteristics in larger patient groups, so far, this has been difficult to achieve in individual patients. Easily detectable molecular biomarkers can be powerful tools, permitting a tailored therapy approach for MS patients. However, only a few molecular biomarkers have been routinely used in clinical practice as the validation process, and their transfer into clinical practice takes a long time. This review describes the characteristics of an ideal MS biomarker, the challenges of establishing new biomarkers, and promising molecular biomarkers from blood or CSF samples used to monitor MS treatment effects in clinical practice.

Oligoclonal Bands in Multiple System Atrophy: Case Report and Proposed Mechanisms of Immunogenicity

Multiple System Atrophy (MSA) is a neurodegenerative disease with heterogeneous manifestations and is therefore difficult to diagnose definitively. Because of this, oftentimes an extensive workup for mimickers is undertaken. We herein report a case where the history and cerebrospinal fluid (CSF) findings of oligoclonal bands suggested an inflammatory disorder. Immunomodulatory therapy failed to ameliorate symptoms or alter the trajectory of continued physical decline, prompting re-visitation of the diagnosis. Oligoclonal bands, while generally viewed as specific to multiple sclerosis or other inflammatory conditions, may be seen in other disease processes. Therefore, this finding should not exclude consideration of neurodegenerative disease.

Determination of CSF GFAP, CCN5, and vWF Levels Enhances the Diagnostic Accuracy of Clinically Defined MS From Non-MS Patients With CSF Oligoclonal Bands

Background

Inclusion of cerebrospinal fluid (CSF) oligoclonal IgG bands (OCGB) in the revised McDonald criteria increases the sensitivity of diagnosis when dissemination in time (DIT) cannot be proven. While OCGB negative patients are unlikely to develop clinically definite (CD) MS, OCGB positivity may lead to an erroneous diagnosis in conditions that present similarly, such as neuromyelitis optica spectrum disorders (NMOSD) or neurosarcoidosis.

Objective

To identify specific, OCGB-complementary, biomarkers to improve diagnostic accuracy in OCGB positive patients.

Methods

We analysed the CSF metabolome and proteome of CDMS (n=41) and confirmed non-MS patients (n=64) comprising a range of CNS conditions routinely encountered in neurology clinics.

Results

OCGB discriminated between CDMS and non-MS with high sensitivity (85%), but low specificity (67%), as previously described. Machine learning methods revealed CCN5 levels provide greater accuracy, sensitivity, and specificity than OCGB (79%, +5%; 90%, +5%; and 72%, +5% respectively) while glial fibrillary acidic protein (GFAP) identified CDMS with 100% specificity (+33%). A multiomics approach improved accuracy further to 90% (+16%).

Conclusion

The measurement of a few additional CSF biomarkers could be used to complement OCGB and improve the specificity of MS diagnosis when clinical and radiological evidence of DIT is absent.

Cerebrospinal fluid cytokine levels are associated with macrophage infiltration into tumor tissues of glioma patients

Background

Diffuse gliomas are the most common malignant tumors of the central nervous system with poor treatment efficacy. Infiltration of immune cells into tumors during immunosurveillance is observed in multiple tumor entities and often associated with a favorable outcome. The aim of this study was to evaluate the infiltration of immune cells in gliomas and their association with cerebrospinal fluid (CSF) cytokine concentrations.

Methods

We applied immunohistochemistry in tumor tissue sections of 18 high-grade glioma (HGG) patients (4 anaplastic astrocytoma, IDH-wildtype WHO-III; 14 glioblastomas (GBM), IDH-wildtype WHO-IV) in order to assess and quantify leucocytes (CD45) and macrophages (CD68, CD163) within the tumor core, infiltration zone and perivascular spaces. In addition, we quantified the concentrations of 30 cytokines in the same patients’ CSF and in 14 non-inflammatory controls.

Results

We observed a significantly higher percentage of CD68⁺ macrophages (21–27%) in all examined tumor areas when compared to CD45⁺ leucocytes (ca. 3–7%); CD163⁺ cell infiltration was between 5 and 15%. Compared to the tumor core, significantly more macrophages and leucocytes were detectable within the perivascular area. The brain parenchyma showing a lower tumor cell density seems to be less infiltrated by macrophages. Interleukin (IL)-7 was significantly downregulated in CSF of GBM patients compared to controls. Additionally, CD68⁺ macrophage infiltrates showed significant correlations with the expression of eotaxin, interferon-γ, IL-1β, IL-2, IL-10, IL-13, IL-16 and vascular endothelial growth factor.

Conclusions

Our findings suggest that the infiltration of lymphocytes is generally low in HGG, and does not correlate with cytokine concentrations in the CSF. In contrast, macrophage infiltrates in HGG are associated with CSF cytokine changes that possibly shape the tumor microenvironment. Although results point towards an escape from immunosurveillance or even exploitation of immune cells by HGG, further studies are necessary to decipher the exact role of the immune system in these tumors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08825-1.

Hiccups and psychosis: two atypical presentations of COVID-19

The WHO defines a possible case of COVID-19 as a person experiencing fever, cough, shortness of breath, and neurological signs including anosmia, ageusia, or dysgeusia. However, experiences from hospitals all over the world have shown that presentations vary widely. Some atypical presentations include cardiac, gastrointestinal, neurological, and cutaneous and while some are driven by the inflammatory response, others are a consequence of the hypercoagulable state. In our emergency department in a private hospital in Mexico City, we received two patients with very different symptoms on the same shift. Two previously healthy men in their 40s presented to the ER with very atypical manifestations of COVID-19. Neither of them complained of fever, cough, or shortness of breath. The first referred a 3-day history of hiccups that had not resolved with metoclopramide. The second presented with an acute episode of altered mental status. While the first case revealed lung involvement of the disease, the second case had a clean chest CT scan. These cases are relevant as manifestations of COVID-19 vary widely, especially in previously healthy young adults.

Evidence of Oligoclonal Bands Does Not Exclude Non-Inflammatory Neurological Diseases

Cerebrospinal fluid analysis is an essential part of the diagnostic workup in various neurological disorders. Evidence of an intrathecal immunoglobulin synthesis, as demonstrated by Reiber’s diagram or the more sensitive oligoclonal bands (OCB), are typical for neuroinflammatory diseases, and normally not expected in non-inflammatory neurological diseases. Therefore, patients with non-inflammatory neurological diseases are often used in control groups in studies investigating autoimmune diseases of the central nervous system. However, data about the frequency of intrathecal immunoglobulin synthesis in non-inflammatory neurological disease are scarce. The cerebrospinal fluid (CSF) records of a total of 3622 patients were screened and 2114 patients included with presumably non-inflammatory neurological diseases like dementia, idiopathic peripheral neuropathy, motoneuron disease, stroke, and epileptic seizures. Evidence of an intrathecal immunoglobulin synthesis can be found with low frequency also in non-inflammatory neurological diseases. A much higher rate of patients showed intrathecal immunoglobulin synthesis as demonstrated by OCB than by Reiber’s diagram. In patients with disorders of the peripheral nervous system the frequency of OCB was much lower than in patients presenting with central nervous system manifestations. Evidence of an intrathecal immunoglobulin synthesis should not automatically lead to exclusion of non-inflammatory neurological diseases but should rather prompt the way to investigate for the origin of the intrathecal immunoglobulin synthesis.

E.U. paediatric MOG consortium consensus: Part 3 - Biomarkers of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders

A first episode of acquired demyelinating disorder (ADS) in children is a diagnostic challenge as different diseases can express similar clinical features. Recently, antibodies against myelin oligodendrocyte glycoprotein (MOG) have emerged as a new ADS biomarker, which clearly allow the identification of monophasic and relapsing ADS forms different from MS predominantly in children. Due to the novelty of this antibody there are still challenges and controversies about its pathogenicity and best technique to detect it. In this manuscript we will discuss the recommendations and caveats on MOG antibody assays, role in the pathogenesis, and additionally discuss the usefulness of other potential new biomarkers in MOG-antibody associated disorders (MOGAD).

Molecular biomarkers in multiple sclerosis

Multiple sclerosis (MS) is an inflammatory-neurodegenerative disease of the central nervous system presenting with significant inter- and intraindividual heterogeneity. However, the application of clinical and imaging biomarkers is currently not able to allow individual characterization and prediction. Complementary, molecular biomarkers which are easily quantifiable come from the areas of immunology and neurobiology due to the causal pathomechanisms and can excellently complement other disease characteristics. Only a few molecular biomarkers have so far been routinely used in clinical practice as their validation and transfer take a long time. This review describes the characteristics that an ideal MS biomarker should have and the challenges of establishing new biomarkers. In addition, clinically relevant and promising biomarkers from the blood and cerebrospinal fluid are presented which are useful for MS diagnosis and prognosis as well as for the assessment of therapy response and side effects.

Collection and Analyses of Cerebrospinal Fluid for Pediatric Translational Research

Cerebrospinal fluid sample collection and analysis is imperative to better elucidate central nervous system injury and disease in children. Sample collection methods are varied and carry with them certain ethical and biologic considerations, complications, and contraindications. Establishing best practices for sample collection, processing, storage, and transport will ensure optimal sample quality. Cerebrospinal fluid samples can be affected by a number of factors including subject age, sampling method, sampling location, volume extracted, fraction, blood contamination, storage methods, and freeze-thaw cycles. Indicators of sample quality can be assessed by matrix-associated laser desorption/ionization time-of-flight mass spectrometry and include cystatin C fragments, oxidized proteins, prostaglandin D synthase, and evidence of blood contamination. Precise documentation of sample collection processes and the establishment of meticulous handling procedures are essential for the creation of clinically relevant biospecimen repositories. In this review we discuss the ethical considerations and best practices for cerebrospinal fluid collection, as well as the influence of preanalytical factors on cerebrospinal fluid analyses. Cerebrospinal fluid biomarkers in highly researched pediatric diseases or disorders are discussed.

[Clinical characteristics and diagnosis of disseminated encephalomyelitis in adults]

AIM

To analyze clinical, neuroimaging and laboratory characteristics of acute disseminated encephalomyelitis (ODEM) in adults with an analysis of the frequency of diagnostic errors at the initial examination stage.

MATERIAL AND METHODS

The study included 23 patients hospitalized with a diagnosis of ODEM. The analysis of clinical characteristics, MRI results and cerebrospinal fluid (CSF) was performed. The diagnosis of the disease in each case was specified after a full examination and dynamic observation.

RESULTS

The diagnosis of ODEM was confirmed only in 16 cases. In 6 cases, the final diagnosis of multiple sclerosis (MS) was made, and one case of Susak syndrome, primary CNS lymphoma and levamisole-associated multifocal inflammatory leukoencephalopathy was also detected. It has been shown that ODEM in adults is characterized by the acute development of multifocal brain lesions in combination with clinical manifestations of encephalopathy, which in half of cases is preceded by an infectious disease. There were no specific clinical, neuroimaging and laboratory features, which could allow differentiation of ODEM from onset of MS.

CONCLUSION

To make a correct diagnosis in the first episode of acute multifocal brain lesion, a dynamic observation, including repeated MRI, is needed. The development of specific biomarkers may be of great importance for the early differential diagnosis of demyelinating diseases.

Association of cerebrospinal fluid kappa free light chains with the intrathecal polyspecific antiviral immune response in multiple sclerosis

The polyspecific B-lymphocyte response to neurotropic viruses such as measles (M), rubella (R) and varicella zoster (Z), known as MRZ reaction, is to-date the most specific neurochemical marker for multiple sclerosis (MS). The aim of this study was to investigate a possible association of immunoglobulin (Ig) kappa (κ-) and lambda (λ-) free light chains (FLC) with the presence of the MRZ reaction in multiple sclerosis. Immunoglobulin κ- and λ-FLC, MRZ reaction, oligoclonal IgG bands (OCB), and cerebrospinal fluid (CSF) routine parameters were measured in 65 MS patients. OCB were detected in 97% of MS patients, intrathecal IgG synthesis according to Reiber was detectable in 57%, an elevated IgG index (>0.7) in 66% and the MRZR was positive in 45%. All investigated κ-values (CSF κFLC, CSF-serum ratio of κFLCs (QκFLC), and κFLC index (κFLC/QAlbumin)) were significantly higher in patients with positive MRZ reaction as compared to MRZ negative MS patients. In contrast, λ-values showed no significant differences. Additionally to the putative diagnostic sensitivity and prognostic value of κFLC, the association of κFLC with a highly specific neurochemical marker for MS - the MRZ reaction, especially the determination of κFLCs is an informative tool to assess the B-cell response and determine its extent in MS patients.

Autoimmune Ataxia During Maintenance Therapy for Acute Lymphoblastic Leukemia

Neurologic dysfunction during acute lymphoblastic leukemia treatment is commonly associated with chemotherapy. Nonchemotherapy contributions should be considered for persistent atypical symptoms. We describe a boy with acute lymphoblastic leukemia who developed recurrent fevers, diarrhea, progressive ataxia, and neuropsychiatric impairment during maintenance chemotherapy. He was found to have cytomegalovirus in his serum and colon, but not in his cerebrospinal fluid. Instead, his cerebrospinal fluid revealed oligoclonal bands not present in the serum, suggesting an autoimmune process. Prompt treatment with ganciclovir and immunotherapy resulted in marked clinical improvement. Early recognition and treatment of an autoimmune encephalitis is paramount for optimal clinical outcome.

Misdiagnosis of multiple sclerosis: Impact of the 2017 McDonald criteria on clinical practice

Misdiagnosis of multiple sclerosis (MS) (the incorrect assignment of a diagnosis of MS) remains a problem in contemporary clinical practice. Studies indicate that misdiagnosed patients are often exposed to prolonged unnecessary health care risks and morbidity. The recently published 2017 revision of the McDonald criteria for the diagnosis of MS provides an opportunity to consider the effect of these revisions on the problem of MS misdiagnosis. The 2017 McDonald criteria include several new recommendations to reduce potential for misdiagnoses. The criteria should be used for the types of patients in which validation studies were performed, specifically those patients who present with typical demyelinating syndromes. MRI lesion characteristics were defined for which McDonald criteria would be expected to perform with accuracy. However, 2017 revisions, which now include assessment for cortical lesions, and the inclusion of symptomatic lesions and positive oligoclonal bands for the fulfillment of diagnostic criteria, may have the potential to lead to misdiagnosis of MS if not applied appropriately. While the 2017 McDonald criteria integrate issues relating to MS misdiagnosis and incorporate specific recommendations for its prevention more prominently than prior criteria, the interpretation of clinical and radiologic assessments upon which these criteria depend will continue to allow misdiagnoses. In patients with atypical clinical presentations, the revised McDonald criteria may not be readily applied. In those situations, further evaluation or monitoring rather than immediate diagnosis of MS is prudent.

Glioblastoma as differential diagnosis of autoimmune encephalitis

OBJECTIVE

To identify the clinical and radiological features that should raise suspicion for the autoimmune encephalitis (AE)-like presentation of glioblastoma.

METHODS

This is an observational, retrospective case series of patients referred to the French National Reference Center on Paraneoplastic Neurological Diseases for suspected AE (possible, probable or definite, using the 2016 criteria) who later received a final diagnosis of glioblastoma according to 2016 WHO criteria. An extensive literature search was also conducted for similar existing cases.

RESULTS

Between 2014 and 2016, 306 patients were referred to our center for suspected AE. Six of these patients (2%) later developed pathologically confirmed glioblastoma. Thirteen patients (9 male) were included for analysis (6 from the present series and 7 from the literature); median age was 63. Initially, a diagnosis of AE was clinically suspected based on: working memory deficits (77%), seizures (62%) (including status epilepticus in 23%), and psychiatric symptoms (46%). Initial brain MRI was not in favor of a typical glioblastoma pattern and showed bilateral (54%) or unilateral selective limbic involvement. Five patients exhibited initial slight contrast enhancement. A clear inflammatory CSF was present in five patients and three from the literature showed autoantibody positivity (NMDAR, VGKC, GluRepsilon2). Median delay between suspicions of AE to GBM diagnosis was 3 months (range 1.5-24) and one patient from the literature was diagnosed post-mortem.

CONCLUSIONS

An alternative diagnosis of glioblastoma should be considered in patients presenting initially as AE, especially in patients who do not fulfill the criteria for definite AE and in those with a poor clinical evolution despite initial improvement.

The MRZ reaction as a highly specific marker of multiple sclerosis: re-evaluation and structured review of the literature

BACKGROUND

It has long been known that the majority of patients with multiple sclerosis (MS) display an intrathecal, polyspecific humoral immune response to a broad panel of neurotropic viruses. This response has measles virus, rubella virus and varicella zoster virus as its most frequent constituents and is thus referred to as the MRZ reaction (MRZR).

OBJECTIVE

Re-evaluation of the specificity of MRZR as a marker of MS.

METHODS

Structured review of the existing English-, German- and Spanish-language literature on MRZR testing, with evaluation of MRZR in a cohort of 43 unselected patients with MS and other neurological diseases as a proof of principle.

RESULTS

A positive MRZ reaction, defined as a positive intrathecal response to at least two of the three viral agents, was found in 78% of MS patients but only in 3% of the controls (p < 0.00001), corresponding to specificity of 97%. Median antibody index values were significantly lower in non-MS patients (measles, p < 0.0001; rubella, p < 0.006; varicella zoster, p < 0.02). The 30 identified original studies on MRZR reported results from 1478 individual MRZR tests. A positive MRZR was reported for 458/724 (63.3%) tests in patients with MS but only for 19/754 (2.5%) tests in control patients (p < 0.000001), corresponding to cumulative specificity of 97.5% (CI 95% 96-98.4), cumulative sensitivity of 63.3% (CI 95% 59.6-66.8) (or 67.4% [CI 95% 63.5-71.1] in the adult MS subgroup), a positive likelihood ratio of 25.1 (CI 95% 16-39.3) and a negative likelihood ratio of 0.38 (CI 95% 0.34-0.41). Of particular note, MRZR was absent in 52/53 (98.1%) patients with neuromyelitis optica or MOG-IgG-positive encephalomyelitis, two important differential diagnoses of MS.

CONCLUSION

MRZR is the most specific laboratory marker of MS reported to date. If present, MRZR substantially increases the likelihood of the diagnosis of MS. Prospective and systematic studies on the diagnostic and prognostic impact of MRZR testing are highly warranted.

New type of encephalomyelitis responsive to trimethoprim/sulfamethoxazole treatment in Japan

Objective:

To determine the causative pathogen and investigate the effective treatment of a new type of encephalomyelitis with an unknown pathogen in Japan and report the preliminary ultrastructural and genomic characterization of the causative agent.

Methods:

From 2005 to 2012, we treated 4 Japanese patients with geographic clustering and comparable clinical features, serum/CSF cytology, and radiologic findings. Brain biopsy was conducted in all patients to analyze neuropathologic changes by histology, and electron microscopy was applied to reveal the features of the putative pathogen. Genomic DNA was obtained from the affected brain tissues and CSF, and an unbiased high-throughput sequencing approach was used to screen for specific genomic sequences indicative of the pathogen origin.

Results:

All patients exhibited progressive dementia with involuntary tongue movements. Cytologic examination of CSF revealed elevated mononuclear cells. Abnormal MRI signals were observed in temporal lobes, subcortical white matter, and spinal cord. Biopsied brain tissue exhibited aggregated periodic acid-Schiff–positive macrophages and 2–7 μm diameter round/oval bodies without nuclei or cell walls scattered around the vessels. Unbiased high-throughput sequencing identified more than 100 archaea-specific DNA fragments. All patients were responsive to trimethoprim/sulfamethoxazole (TMP-SMX) plus corticosteroid therapy.

Conclusions:

We report 4 cases of encephalomyelitis due to an unknown pathogen. On the basis of ultrastructural and genomic studies, we propose a new disease entity resulting from a causative pathogen having archaeal features. TMP-SMX therapy was effective against this new type of encephalomyelitis.

Cerebrospinal fluid biochemical studies in patients with Parkinson's disease: toward a potential search for biomarkers for this disease

The blood-brain barrier supplies brain tissues with nutrients and filters certain compounds from the brain back to the bloodstream. In several neurodegenerative diseases, including Parkinson's disease (PD), there are disruptions of the blood-brain barrier. Cerebrospinal fluid (CSF) has been widely investigated in PD and in other parkinsonian syndromes with the aim of establishing useful biomarkers for an accurate differential diagnosis among these syndromes. This review article summarizes the studies reported on CSF levels of many potential biomarkers of PD. The most consistent findings are: (a) the possible role of CSF urate on the progression of the disease; (b) the possible relations of CSF total tau and phosphotau protein with the progression of PD and with the preservation of cognitive function in PD patients; (c) the possible value of CSF beta-amyloid 1-42 as a useful marker of further cognitive decline in PD patients, and (d) the potential usefulness of CSF neurofilament (NFL) protein levels in the differential diagnosis between PD and other parkinsonian syndromes. Future multicentric, longitudinal, prospective studies with long-term follow-up and neuropathological confirmation would be useful in establishing appropriate biomarkers for PD.

Concomitant amyotrophic lateral sclerosis and paraclinical laboratory features of multiple sclerosis: coincidence or causal relationship?

We report a 55-year-old patient, presenting with paresis, muscle atrophy and dysarthria, all symptoms accordable to definite amyotrophic lateral sclerosis (ALS). However, MRI and cerebrospinal fluid show abnormalities typical of multiple sclerosis (MS). On the basis of this case report, we discuss possible overlaps between both diseases by comparing clinical and paraclinical features including laboratory, radiological and electrophysiological diagnostics. As genetic, as well as environmental, factors are assumed to be involved in the development of both the diseases, literature is reviewed according to similar cases, results of autopsies and possible parallels in pathogenesis. In summary, based on the data currently available, the hypothesis of ALS being a neurodegenerative multisystem disorder, a common pathophysiological pathway or, alternatively, a random comorbidity of ALS and MS in this patient has to be discussed.

Biomarkers of inflammatory and auto-immune central nervous system disorders

PURPOSE OF REVIEW

Inflammatory and auto-immune disorders of the central nervous system are a heterogeneous group of disorders. Many of these disorders are potentially treatable with immune therapies that can reduce disability or prevent death. We review the clinical value of biomarkers which can aid in the diagnosis of paediatric inflammatory and auto-immune central nervous system (CNS) disorders.

RECENT FINDINGS

This review will first describe the clinical usefulness of nonspecific biomarkers of CNS inflammation such as cerebrospinal fluid neopterin and oligoclonal bands. Neopterin is produced by immune and neuronal cells after stimulation by interferon species and is increased in a broad range of inflammatory and auto-immune CNS disorders. Oligoclonal bands represent clonal production of immunoglobulin G in the CNS and are present in demyelinating, auto-immune, and infectious CNS disorders. In addition, we will review new advances in the immunogenetic investigation of familial auto-inflammatory disorders such as Aicardi-Goutières syndrome and Chronic Infantile Neurologic Cutaneous Articular syndrome. Finally, we will review the clinical utility of auto-antibodies in CNS disorders, with specific focus on auto-antibodies that bind to cell surface proteins such as N-methyl-D-asparate receptor, voltage-gated potassium channels, myelin oligodendrocyte glycoprotein, and aquaporin-4.

SUMMARY

These biomarkers are increasingly important in the recognition and treatment of inflammatory and auto-immune CNS disorders. Like many biomarkers in paediatric practice, it is essential to interpret the findings in the context of the patient history and examination.

Epilepsy and the immune system: is there a link?

The concept that the immune system plays a role in the epileptogenic process of some epileptic syndromes was first proposed more than 20 years ago. Since then, numerous studies have reported on the existence of a variety of immunological alterations in epileptic patients, on the observation of favourable responses of refractory epilepsy syndromes to immunomodulatory treatment, and on the association of certain well-known immune-mediated disease states with epilepsy. This review comprehensively recapitulates the currently available evidence supporting or arguing against the possible involvement of the immune system in the pathogenesis of certain types of epilepsy. It is concluded that an abundance of facts is in support of this concept and that further studies should be directed at substantiating the pathogenic significance of (auto)immune responses in certain types of epilepsy. Current progress in the functional and molecular immunological research techniques will indisputably contribute to the elucidation of this link.

Changes of intrathecal immunoglobulin synthesis in various types of dementias

Our examinations were finished on 80 patients with different dementia forms. We specified the concentration of liquor immunoglobulins with the nephelometrical method, and concluded the presence of intrathecal immunoglobulin (IgG, IgM and IgA) synthesis on the basis of the Link index. In the cases of senile dementia, SDAT and AD, we found altered blood-brain barrier function. We detected intrathecal IgG and IgA synthesis at AD patients, while the synthesis of all the three immunoglobulins was characteristic for the Jakob-Creutzfeld disease. On the basis of our results, we came to the conclusion that, at the different dementias, the immunopathological occurrences play different roles in the development of the disease.

Cerebrospinal fluid markers of Alzheimer's disease

OBJECTIVE

To review studies on cerebrospinal fluid (CSF) in patients with Alzheimer's disease (AD) in order to answer the question whether CSF contains a specific marker which can be used to support a clinical diagnosis of AD.

DATA SOURCES

Studies identified through an English-language literature search using MEDLINE (1966 to 1990) and a review of bibliographies of relevant articles.

STUDY SELECTION

All studies on CSF in AD patients were selected. Double publications on the same original data were not included. Otherwise, no particular selection was made.

DATA EXTRACTION

The diagnostic utility of more than 60 substances, including CSF measures related to classical neurotransmitters, (neuro)peptides, proteins, amino acids, purines, trace elements, and constituents of senile plaques and neurofibrillary tangles, is evaluated. Clinical epidemiological criteria for deciding on the usefulness of new diagnostic methods are emphasized in this analysis.

DATA SYNTHESIS

Concentrations of some CSF constituents are consistently found to be significantly changed in AD. However, overlap with data of control populations and methodological shortcomings in study design, limit the diagnostic value of all CSF measurements reviewed.

CONCLUSIONS

None of the CSF constituents studied so far can be used in support of the diagnosis of AD. However, increased knowledge concerning macromolecular abnormalities in amyloid containing plaques and neurofibrillary tangles makes the outlook for a diagnostic test for AD on CSF promising.

CSF proteins in neurological disorders analyzed by immobilized PH gradient isoelectric focusing using narrow PH gradients

We analyzed 352 paired CSF and serum samples with isoelectric focusing and immobilized pH gradients (IPG-IEF) using three different gradients. All MS patients (n = 35) had several (from 5 to 30) oligoclonal bands (OBs) in the CSF and most of them had few (from 1-8) OBs in serum. 54.5% patients with CNS infections (n = 12) had oligoclocal bands. OBs in these patients were fewer in number and located at the more acidic pH region compared with the MS samples. Also, corresponding serum bands were more often recognized. We suggest that IPG-IEF improves the diagnostic evaluation of the oligoclonal band pattern. The possibility of the use of extremely narrow gradients makes it a valuable tool for the analysis of selective proteins in various disorders.

High-dose intravenous-penicillin in neurosyphilis: effect on intrathecal synthesis of IgG, IgM, IgA and IgD

We evaluated occurrence and levels of intrathecal synthesis of IgG, IgM, IgA and IgD by calculating corresponding index values in 8 patients with definite and 4 with suspected or possible neurosyphilis, prior to, during and after high-dose intravenous penicillin therapy. Four patients with active neurosyphilis displayed intrathecal synthesis of IgG, IgM and IgA. Only 2 of them showed elevated IgD index, and both had taboparesis, pleocytosis and positive VDRL in CSF, and simultaneous elevation of the IgG, IgA and especially of the IgM indices. This suggests that intrathecal synthesis of IgD may occur in patients with severe CNS inflammation in response to diffuse CNS treponemal damage. Penicillin therapy incited transitory elevation of one or more of the immunoglobulin index values in most patients, possibly in response to massive treponemal lysis inside the CNS. Thereafter, the values became mostly normalized but exceptions occurred, including one patient who had elevated IgG and IgM index which persisted 31 months after therapy. Our data indicate that determinations of immunoglobulin indices performed on consecutive specimens from individual patients with neurosyphilis may be helpful in the evaluation of treatment.

Multiple sclerosis in childhood: contribution of serial MRI to earlier diagnosis

The authors report six children (five girls, one boy) aged 11 to 13 years, of whom four had clinically definite multiple sclerosis (MS) and two had laboratory-supported definite MS. All had brain white matter abnormalities indicative of MS. In three cases, positive findings on the first MRI contributed significantly to their early diagnosis. Follow-up MRI studies over an average period of five months detected morphological changes in three of the children, although there was no concomitant clinical evidence. This raises the question of whether changes in clinically 'silent' lesions on follow-up MRI are antecedents of the essential MS criterion of dissemination over time, which could lead to earlier diagnosis of childhood MS. With cranial computerized tomography (CT) during the first clinical attack, a large focus with a lamellar structure mimicked a brain tumour in two patients. As CT also misses additional small lesions, it should no longer be used as the primary diagnostic method.

Clinical course and long-term prognosis of acute transverse myelopathy

The clinical characteristics and course of acute transverse myelopathy (ATM) was studied. One patient developed multiple sclerosis. In 1 patient ATM was caused by tumour-cell embolization of the intramedullar vessels; 30 aged 12-74 years (median 36 years) had ATM of unknown course, of these, 13 had symptoms of a preceding viral-like infection, 18 had back-pain and 10 signs of spinal shock. The time from onset of ATM to maximum deficit varied from less than 1 h to 20 days. The thoracic region was the most common level of cord damage. Follow-up was possible in 29 cases; 2 died (2 and 8 months after onset), of the surviving 27 (follow-up 1-13 years, median 6 years) one third had a good outcome, one third a fair, while one third remained paraplegic, incontinent with severe sensory deficits. Back-pain and signs of spinal shock indicated a poor outcome.

Intrathecal synthesis of immunoglobulin G in vascular dementia

Serum and CSF from 53 vascular dementia (VD) patients and 50 controls were analysed to investigate the possibility of an intrathecal synthesis of IgG, defined as an elevated IgG index (greater than or equal to 7) and/or presence of oligoclonal IgG in cerebrospinal fluid (CSF), but not in serum. Five (9%) patients and no controls exhibited an intrathecal synthesis of IgG. The IgG index increased with the degree of dementia (p less than 0.05). It was positively related to presence/absence of hypertension (p less than 0.05) and correlated positively with diastolic blood pressure (p less than 0.05). The findings suggest that immunological factors might be involved in the pathogenesis of VD.

Current perspectives on immunology and psychiatry

We selectively review recent research findings in the field of psychoimmunology which test the hypotheses that immunological dysfunction may be aetiologically related to mental illnesses such as schizophrenia, and that certain morbid affective states such as depression and other forms of psychosocial distress may be the cause of immunosuppression and through this mechanism affect the outcome of illnesses such as cancer. Our examination of research implicating immunological or infective mechanisms in the aetiology of schizophrenia indicates that most studies have been unable to control for major methodological difficulties but the compatibility of these theories with the dopamine hypothesis suggests that further research attention is warranted. More clearly, there is growing evidence demonstrating a link between depression, other states of psychological distress and immunosuppression, but the clinical significance of these findings remains uncertain. The complex relationship between stress and the outcome of illnesses such as cancer is discussed and the possible implications of these findings for clinical psychiatry are suggested.

Oligoclonal bands staining for IgG, IgA, IgM, and kappa and lambda light chains in cerebrospinal fluid of patients with multiple sclerosis

We investigated the oligoclonal bands (OB) in CSF of patients with multiple sclerosis (MS), Guillain-Barré syndrome (GBS) and aseptic meningitis (AS) using polyacryamide or agarose isoelectric focusing following electroblotting and immunostaining for IgG, IgA, IgM and light chains. OB staining for IgG was detected in 80% of patients with MS, 25% with GBS and 13% with AS. OB staining for IgA and IgM was not detected in any disease. In MS, OB were stained only for the kappa or lambda light chains, which was compatible with OB staining for IgG. These results suggest that in MS, OB are monoclonal because they can be stained for gamma heavy chains and for only one light chains.

Cerebrospinal fluid protein analysis in diseases of the nervous system

Electrophoretic studies of human CSF proteins from patients with diseases of the NS are reviewed. Various 1-DE methods are of similar value in identifying the non-specific OBs, which are helpful in the diagnosis of MS and recurrent GBS. In early and subclinical MS, OBs are of prognostic value, with IEF gels having the greater resolution. Silver-stained 2-DE gels provide the equivalent information to the OBs on 1-DE gels, with even greater sensitivity, and yield additional disease-associated protein data. Two proteins have proven to have diagnostic value in CJD and other changes that are still being evaluated have been identified in Parkinson's disease, GBS, Alzheimer's disease, schizophrenia and Herpes simplex encephalitis. The vastly improved CSF protein information obtained with silver-stained 2-DE gels heralds both a change from the relatively limited applications with 1-DE methods and also the need to adopt this approach in the routine clinical laboratory.

Oligoclonal immunoglobulin bands in cerebrospinal fluid of patients with Alzheimer's disease and vascular dementia

We examined serum and cerebrospinal fluid (CSF) of 16 patients with Alzheimer's disease (AD), 28 patients with vascular dementia (VD), their age-matched controls and multiple sclerosis (MS) patients in order to evaluate the humoral immune response within the central nervous system both quantitatively and qualitatively. Intra-blood-brain barrier (BBB) protein synthesis was calculated by CSF IgG index. The presence of oligoclonal banding (OCB) was investigated with agarose isoelectric focusing (IEF) followed by immunoblotting with antihuman IgG. No patient with AD and only 4 patients with VD had slightly elevated IgG indexes, and no statistically significant differences in the indexes were found between the two groups. No bands were found in the CSF of AD patients but 3 VD patients had OCB in both serum and CSF. One VD patient had bands in serum but no bands in CSF. No kappa or lambda free light chains were found in those demented patients with demonstrable bands in the CSF and serum. No OCB were found in control sera and CSF. For comparison, the majority of patients with MS had OCB in CSF. Thus, no consistent increase of intrathecal protein synthesis was found in patients with AD and VD. Methodological differences explain at least part of the conflicting results published earlier.