Atypical inflammatory demyelinating syndromes of the CNS

Recovery from acute haemorrhagic leucoencephalitis secondary to COVID-19

A man in his 50s presented with sudden onset expressive aphasia and right-sided facial droop after experiencing coryzal symptoms and malaise for 7 days prior to admission. A brain MRI showed a rapidly progressive mass effect across both hemispheres and cerebrospinal fluid analysis revealed neutrophil predominance with raised protein levels. Acute disseminated encephalomyelitis was provisionally diagnosed, and high-dose methylprednisone was initiated.On admission to the high dependency unit, the patient tested positive for COVID-19 and was treated with appropriate therapeutic agents for severe COVID-19. A subsequent brain biopsy confirmed a demyelinating process, strongly indicating a diagnosis of acute haemorrhagic leucoencephalitis when correlated with the presence of severe oedema on imaging. Nine sessions of plasma exchange were provided over 18 days.At the time of writing, the patient has made an excellent recovery. We urge clinicians to consider this diagnosis and these treatment options for an otherwise devastating condition.

Atypical Demyelinating Disorders: MR Imaging Features, Atypical Triggers, and Etiopathogenesis

Atypical demyelinating lesions (ADLs) can be idiopathic, occurring as isolated and self-limited events, or can appear in different stages of relapsing demyelinating diseases. Not infrequently, ADLs occur in inflammatory syndromes associated with exogenous or endogenous toxic factors, metabolic imbalance, or infectious agents. It is important to recognize imaging patterns that indicate an inflammatory/demyelinating substrate in central nervous system lesions and to investigate potential triggers or complicating factors that might be associated. The prognostic and treatment strategies of ADLs are influenced by the underlying etiopathogenesis.

Neuromyelitis optica spectrum disorder: pathophysiological approach

Aim: To review the main pathological findings of Neuromyelitis Optica Spectrum Disorder (NMOSD) associated with the presence of autoantibodies to aquaporin-4 (AQP4) as well as the mechanisms of astrocyte dysfunction and demyelination. Methods: An comprehensive search of the literature in the field was carried out using the database of The National Center for Biotechnology Information from . Systematic searches were performed until July 2022. Results: NMOSD is an inflammatory and demyelinating disease of the central nervous system mainly in the areas of the optic nerves and spinal cord, thus explaining mostly the clinical findings. Other areas affected in NMOSD are the brainstem, hypothalamus, and periventricular regions. Relapses in NMOSD are generally severe and patients only partially recover. NMOSD includes clinical conditions where autoantibodies to aquaporin-4 (AQP4-IgG) of astrocytes are detected as well as similar clinical conditions where such antibodies are not detected. AQP4 are channel-forming integral membrane proteins of which AQ4 isoforms are able to aggregate in supramolecular assemblies termed orthogonal arrays of particles (OAP) and are essential in the regulation of water homeostasis and the adequate modulation of neuronal activity and circuitry. AQP4 assembly in orthogonal arrays of particles is essential for AQP4-IgG pathogenicity since AQP4 autoantibodies bind to OAPs with higher affinity than for AQP4 tetramers. NMOSD has a complex background with prominent roles for genes encoding cytokines and cytokine receptors. AQP4 autoantibodies activate the complement-mediated inflammatory demyelination and the ensuing damage to AQP4 water channels, leading to water influx, necrosis and axonal loss. Conclusions: NMOSD as an astrocytopathy is a nosological entity different from multiple sclerosis with its own serological marker: immunoglobulin G-type autoantibodies against the AQP4 protein which elicits a complement-dependent cytotoxicity and neuroinflammation. Some patients with typical manifestations of NMSOD are AQP4 seronegative and myelin oligodendrocyte glycoprotein positive. Thus, the detection of autoantibodies against AQP4 or other autoantibodies is crucial for the correct treatment of the disease and immunosuppressant therapy is the first choice.

Baló concentric sclerosis: Literature review and report of two cases

BACKGROUND

Baló's concentric sclerosis (BCS) is a rare variant of multiple sclerosis characterized by unique pathological features of alternating demyelination and preserved myelin.

OBJECTIVES

To describe two cases of BCS, radiological and pathological findings and its clinical course.

RESULTS

We report two distinct cases of BCS that presented with unique MRI findings suggestive of BCS, but with different clinical courses and responses to treatment. The first case demonstrated substantial recovery following corticosteroid therapy, while the second case, initially suspected to be a malignant tumour, showed improvement after surgical intervention and immunoglobulin therapy.

CONCLUSION

These cases highlight the variability in presentation and course of BCS, underscoring the challenges in diagnosis and the importance of considering BCS in the differential diagnosis of demyelinating and tumefactive lesions. The cases also emphasize the potential for favourable outcomes with appropriate management, challenging the traditional view of BCS as uniformly severe.

A 42-Year-Old Woman With Rapidly Expanding White Matter Lesions: From the National Multiple Sclerosis Society Case Conference Proceedings

A 42-year-old woman and active cocaine user complained of subacutely worsening blurred vision and imbalance. Examination of the brain MRI showed rapidly expanding white matter lesions. Brain biopsy was consistent with inflammatory demyelination. Given an unusual presentation and a history of cocaine use, a broad differential diagnosis was considered including neurologic toxidromes.

Clinical and radiological characteristics and outcomes of patients with recurrent or relapsing tumefactive demyelination

BACKGROUND

Relapsing or recurrent tumefactive demyelination is rare and has not been studied beyond individual case reports.

OBJECTIVE

We examined the clinical course, neuroimaging, cerebrospinal fluid (CSF), treatment and outcomes of patients with recurrent tumefactive demyelinating lesions (TDLs).

METHODS

We used PubMed to identify reports of recurrent TDLs and included the details of an additional, unpublished patient.

RESULTS

We identified 18 cases (11F, 7 M). The median age at onset of the index TDL was 37 years (range 12-72) and most were solitary lesions 72 % (13/18). CSF-restricted oligoclonal bands (OCBs) were detected in 25 % (4/16). Only one of those tested (n = 13) was positive for AQP4-IgG. A moderate-to-marked treatment response (high dose corticosteroid with or without additional plasmapheresis, IVIg or disease modifying therapies) was evident in 89 % of treated patients. Median EDSS at the median follow-up of 36 months (range 6-144) was 2 (range 1-10). Most remained ambulatory (EDSS < 4 in 13/18), but 1 patient died.

CONCLUSION

The median age of patients with relapsing TDLs is similar to that of typical MS, but differences include a lower female:male sex ratio, larger lesions, and a comparative lack of CSF-restricted OCBs. Outcomes vary among this group of patients ranging from minimal disability through to death.

Inflammatory lesions of the brainstem: Keys for the diagnosis by MRI

OBJECTIVE

To describe the magnetic resonance imaging (MRI) findings for the most common inflammatory and immune-mediated diseases that involve the brainstem.

CONCLUSION

Inflammatory lesions involving the brainstem are associated with a wide range of autoimmune, infectious, and paraneoplastic syndromes, making the differential diagnosis complex. Being familiar with these entities, their clinical characteristics, and their manifestations on MRI, especially the number of lesions, their shape and extension, and their appearance in different sequences, is useful for orienting the radiological diagnosis.

Defining the natural history of tumefactive demyelination: A retrospective cohort of 257 patients

OBJECTIVE

To describe demographic, clinical, and radiographic features of tumefactive demyelination (TD) and identify factors associated with severe attacks and poor outcomes.

METHODS

Retrospective review of TD cases seen at Mayo Clinic, 1990-2021.

RESULTS

Of 257 patients with TD, 183/257 (71%) fulfilled the 2017 multiple sclerosis (MS) McDonald criteria at the last follow-up, 12/257 (5%) had myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), 0 had aquaporin-4-IgG seropositive neuromyelitis optic spectrum disorders (AQP4+ NMOSD), and 62/257 (24%) were cryptogenic. Onset before age 18 was present in 18/257 (7%). Female to male ratio was 1.3:1. Cerebrospinal fluid oligoclonal (CSF) bands were present in 95/153 (62%). TD was the first demyelinating attack in 176/257 (69%). At presentation, 59/126 (47%) fulfilled Barkhof criteria for dissemination in space, 59/100 (59%) had apparent diffusion coefficient (ADC) restriction, and 57/126 (45%) had mass effect. Despite aggressive clinical presentation at onset, 181/257 (70%) of patients remained fully ambulatory (Expanded Disability Status Scale [EDSS] ≤4) after a 3.0-year median follow-up duration. Severe initial attack-related disability (EDSS ≥4) was more common in patients with motor symptoms (81/143 vs. 35/106, p < 0.0001), encephalopathy (20/143 vs. 2/106, p < 0.0001) and ADC restriction on initial MRI (42/63 vs. 15/33, p = 0.04). Poor long-term outcome (EDSS ≥4) was more common in patients with older onset age (41.9 ± 15 vs. 36.8 ± 15.6, p = 0.02) and motor symptoms at onset (49/76 vs. 66/171, p < 0.0001).

INTERPRETATION

Most TD patients should be considered part of the MS spectrum after excluding MOGAD and NMOSD. Motor symptoms and older age at presentation portend a poor outcome.

Pseudocystic inflammatory demyelinating lesions in multiple sclerosis: A clinical, radiological, and pathological description

BACKGROUND

Pseudocystic inflammatory demyelinating lesions (PIDLs) are poorly described in MS and might represent a diagnostic challenge.

OBJECTIVES

We described the clinical, radiological, pathological, and follow-up characteristics of 13 PIDL in 9 MS patients.

METHODS

We constituted a single-center retrospective case series of PIDLs in MS, defined on MRI as expansive cyst-like lesions, with a fluid-signal content, and a diameter of 1 cm or more.

RESULTS

PIDL often occurred at first event (56%), were often asymptomatic (69%), and encircled by a hypo-T2 diffusion-restricted rim and a thin ring-like gadolinium enhancement (100%) on magnetic resonance imaging (MRI). Associated typical MS lesions were constant. Biopsies from two PIDLs displayed classical features of active MS, except for unusual edema.

CONCLUSION

PIDLs are clinically unremarkable and associated with a good outcome. Their easily recognizable MRI features could help avoid biopsy.

The Pathological Activation of Microglia Is Modulated by Sexually Dimorphic Pathways

Microglia are the primary immunocompetent cells of the central nervous system (CNS). Their ability to survey, assess and respond to perturbations in their local environment is critical in their role of maintaining CNS homeostasis in health and disease. Microglia also have the capability of functioning in a heterogeneous manner depending on the nature of their local cues, as they can become activated on a spectrum from pro-inflammatory neurotoxic responses to anti-inflammatory protective responses. This review seeks to define the developmental and environmental cues that support microglial polarization towards these phenotypes, as well as discuss sexually dimorphic factors that can influence this process. Further, we describe a variety of CNS disorders including autoimmune disease, infection, and cancer that demonstrate disparities in disease severity or diagnosis rates between males and females, and posit that microglial sexual dimorphism underlies these differences. Understanding the mechanism behind differential CNS disease outcomes between men and women is crucial in the development of more effective targeted therapies.

Case report: MOG-IgG-associated encephalitis with Epstein-Barr virus infection and Alzheimer's pathologic change in cerebrospinal fluid

Immunoglobulin G antibodies to myelin oligodendrocyte glycoprotein (MOG-IgG) associated disease is a rare, demyelinated disease in the central nerve system (CNS) predominately involving optic nerve, spinal cord, and brain leading to optic neuritis (ON), transverse myelitis (TM), encephalitis. The phenotype of MOG-IgG-associated encephalitis is similar to acute disseminated encephalomyelitis (ADEM) presenting with seizures, abnormal behavioral and psychological symptoms, and cognitive impairment. A few brain biopsies show multiple sclerosis (MS) pattern histopathology with T cells, macrophages, and complement activation. To date, how MOG-IgG is produced is unknown. Herein, we report a case of a 32-year-old male with MOG-IgG-associated encephalitis presenting MOG-IgG in cerebrospinal fluid (CSF) but seronegative, as well as Epstein-Barr virus (EBV) infection and Alzheimer's pathologic change in CSF (Aβ42 = 317 pg/ml, T-Tau = 538 pg/ml, p-Tau =10.09 pg/ml). With a combination treatment of administering intravenous immunoglobulin (0.4 mg/kg/d, 5 days) with a low dose of methylprednisolone (80 mg/d, 5 days) and rituximab (100 mg/week, 3 weeks), the patient recovered significantly after 3 months follow-up. This case provides us with new thoughts into the production of MOG-IgG and the possible pathologic mechanism of MOG-IgG-associated disease (MOG-AD) and simultaneously further confirms the interaction between EBV and changes of CSF biomarkers of Alzheimer's disease (AD).

Acute Hemorrhagic Leukoencephalitis (AHLE): A Comprehensive Review on Causes, Symptoms, Link with COVID-19, Diagnosis, and Treatment

Acute hemorrhagic leukoencephalitis (AHLE), also called Hurst disease, is a rare demyelinating disease of the central nervous system (CNS) marked by rapid progression and acute inflammation of the white matter. Due to the correlation in their suspected postinfectious autoimmune pathogenesis, it is regarded as the most severe form of acute disseminated encephalomyelitis (ADEM). Because this clinical scenario has a high mortality rate, aggressive and immediate treatment is required. Although the exact cause of AHLE is unknown, it usually occurs after a bacterial or viral infection, or, less frequently, after a measles or rabies vaccination. AHLE has been reported in patients with coronavirus disease 2019 (COVID-19) as a rare but serious neurological complication. However, due to the lack of evidence-based diagnostic criteria, diagnosis is difficult. The small number of cases described in the literature, which most likely reflects underreporting and/or low incidence, necessitates greater public awareness. Increased clinical suspicion and early imaging identification of this entity may allow clinicians to pursue more aggressive treatment options, potentially reducing fatal outcomes. This study focuses on symptoms and causes of AHLE, difference between AHLE and ADME, diagnosis and treatment of AHLE, and its link with COVID-19.

Pathogenic autoantibodies in multiple sclerosis - from a simple idea to a complex concept

The role of autoantibodies in multiple sclerosis (MS) has been enigmatic since the first description, many decades ago, of intrathecal immunoglobulin production in people with this condition. Some studies have indicated that MS pathology is heterogeneous, with an antibody-associated subtype - characterized by B cells (in varying quantities), antibodies and complement - existing alongside other subtypes with different pathologies. However, subsequent evidence suggested that some cases originally diagnosed as MS with autoantibody-mediated demyelination were more likely to be neuromyelitis optica spectrum disorder or myelin oligodendrocyte glycoprotein antibody-associated disease. These findings raise the important question of whether an autoantibody-mediated MS subtype exists and whether pathogenic MS-associated autoantibodies remain to be identified. Potential roles of autoantibodies in MS could range from specific antibodies defining the disease to a non-disease-specific amplification of cellular immune responses and other pathophysiological processes. In this Perspective, we review studies that have attempted to identify MS-associated autoantibodies and provide our opinions on their possible roles in the pathophysiology of MS.

Exogenous Antioxidants in Remyelination and Skeletal Muscle Recovery

Inflammatory, oxidative, and autoimmune responses cause severe damage to the nervous system inducing loss of myelin layers or demyelination. Even though demyelination is not considered a direct cause of skeletal muscle disease there is extensive damage in skeletal muscles following demyelination and impaired innervation. In vitro and in vivo evidence using exogenous antioxidants in models of demyelination is showing improvements in myelin formation alongside skeletal muscle recovery. For instance, exogenous antioxidants such as EGCG stimulate nerve structure maintenance, activation of glial cells, and reduction of oxidative stress. Consequently, this evidence is also showing structural and functional recovery of impaired skeletal muscles due to demyelination. Exogenous antioxidants mostly target inflammatory pathways and stimulate remyelinating mechanisms that seem to induce skeletal muscle regeneration. Therefore, the aim of this review is to describe recent evidence related to the molecular mechanisms in nerve and skeletal muscle regeneration induced by exogenous antioxidants. This will be relevant to identifying further targets to improve treatments of neuromuscular demyelinating diseases.

Adult-Onset Genetic Central Nervous System Disorders Masquerading as Acquired Neuroinflammatory Disorders: A Review

Importance

Adult-onset genetic disorders may present with clinical and magnetic resonance imaging (MRI) features suggestive of acquired inflammatory diseases. An ever-growing number of potentially treatable adult-onset genetic neuroinflammatory disorders have been described in the past few years that need to be rapidly identified.

Observations

Adult-onset acquired neuroinflammatory disorders encompass a large group of central nervous system (CNS) diseases with varying presentation, MRI characteristics, and course, among which the most common is multiple sclerosis. Despite recent progress, including the discovery of specific autoantibodies, a significant number of adult-onset neuroinflammatory disorders with progressive or relapsing course still remain without a definite diagnosis. In addition, some patients with genetic disorders such as leukodystrophies, hemophagocytic lymphohistiocytosis, or genetic vasculopathies can mimic acquired neuroinflammatory disorders. These genetic disorders, initially described in pediatric populations, are increasingly detected in adulthood thanks to recent progress in molecular genetics and the larger availability of high-throughput sequencing technologies.

Conclusions and Relevance

Genetic adult-onset neuroinflammatory diseases are at the border between primary CNS inflammatory diseases and systemic disorders with multiorgan involvement and predominantly neurologic manifestations. Neurologists must be aware of the main clues and red flags so they can confirm a diagnosis early, when some of these genetic disorders can be successfully treated.

Pure Relapsing Short Myelitis

Background and Objectives

Pure relapsing short myelitis with clinical and paraclinical features suggesting multiple sclerosis (MS) has been described recently. Here, we evaluated the existence of this potential new form of MS by retrospectively searching for similar cases in the databases of the French tertiary MS centers.

Methods

Patients were included based on the present criteria: at least 2 short (<3 vertebral segments) myelitis episodes; minimum follow-up of 3 years; no MS-like brain lesion during all the follow-up; tested negative for both anti–myelin oligodendrocyte glycoprotein and anti–aquaporin 4 antibodies in serum; presence of oligoclonal bands in CSF; and comprehensive workup to exclude alternative diagnoses.

Results

Eighteen patients fulfilled all criteria. The sex ratio (females/males) was 5/1; the median (range) age at first relapse was 35.5 (25–54) years, the disease duration was 80.5 (50–308) months, and the annualized relapse rate was 0.36 (0.1–0.5). The median (range) number of relapses per patient was 2 (2–5), and the median (range) Expanded Disability Status Scale score at last follow-up was 1 (0–7.5). In CSF, the median (range) protein level was 0.34 g/L (0.18–0.77), and the median (range) number of mononuclear cells was 3 (0–28). Spinal cord MRI demonstrated a median (range) number of 2 (1–5) lesions per examination and 3 [1–7] on the last examination. Fifty-five percent of lesions involved the cervical levels. Secondary progressive evolution occurred in 3 of 18 (17%) patients.

Discussion

Pure spinal MS could be a rare entity in the MS disease spectrum. However, the existence of a distinct entity in the inflammatory CNS disorders cannot be excluded.

Sera of Neuromyelitis Optica Patients Increase BID-Mediated Apoptosis in Astrocytes

Neuromyelitis optica (NMO) is a rare disease usually presenting with bilateral or unilateral optic neuritis with simultaneous or sequential transverse myelitis. Autoantibodies directed against aquaporin-4 (AQP4-IgG) are found in most patients. They are believed to cross the blood−brain barrier, target astrocytes, activate complement, and eventually lead to astrocyte destruction, demyelination, and axonal damage. However, it is still not clear what the primary pathological event is. We hypothesize that the interaction of AQP4-IgG and astrocytes leads to DNA damage and apoptosis. We studied the effect of sera from seropositive NMO patients and healthy controls (HCs) on astrocytes’ immune gene expression and viability. We found that sera from seropositive NMO patients led to higher expression of apoptosis-related genes, including BH3-interacting domain death agonist (BID), which is the most significant differentiating gene (p < 0.0001), and triggered more apoptosis in astrocytes compared to sera from HCs. Furthermore, NMO sera increased DNA damage and led to a higher expression of immunological genes that interact with BID (TLR4 and NOD-1). Our findings suggest that sera of seropositive NMO patients might cause astrocytic DNA damage and apoptosis. It may be one of the mechanisms implicated in the primary pathological event in NMO and provide new avenues for therapeutic intervention.

Neuroinflammation in Parkinson's Disease - Putative Pathomechanisms and Targets for Disease-Modification

Parkinson’s disease (PD) is a progressive and debilitating chronic disease that affects more than six million people worldwide, with rising prevalence. The hallmarks of PD are motor deficits, the spreading of pathological α-synuclein clusters in the central nervous system, and neuroinflammatory processes. PD is treated symptomatically, as no causally-acting drug or procedure has been successfully established for clinical use. Various pathways contributing to dopaminergic neuron loss in PD have been investigated and described to interact with the innate and adaptive immune system. We discuss the possible contribution of interconnected pathways related to the immune response, focusing on the pathophysiology and neurodegeneration of PD. In addition, we provide an overview of clinical trials targeting neuroinflammation in PD.

Hybrid 18F-florbetapir PET/MRI for assessing myelin recovery in GFAP-A patients

Glial fibrillary acidic protein astrocytopathy (GFAP-A) is a rare autoimmune disease of the central nervous system that was newly reported in 2016. Previous studies have speculated that the pathological mechanism and clinical outcome of GFAP-A lie in the demyelination of the central nervous system, but due to the limitations of MR, this conclusion has not been further confirmed from the perspective of neuroimaging. A non-invasive, quantitative measurement of demyelination would be clinically valuable, given its critical role in mediating GFAP-A. Here, we report a case in which we use ¹⁸F-florbetapir positron emission tomography-magnetic resonance imaging (PET/MRI) to evaluate myelin recovery with follow-up in the patient with GFAP-A. Our patient displayed a decreased uptake of PET tracer ¹⁸F-florbetapir in the brain lesions and lower distribution volume ratio in the damaged white matter lesions compared to the normal-appearing white matter, indicating significant intracranial demyelination. After treatment, the ¹⁸F-florbetapir PET/MRI examination showed a significant increase in the uptake of ¹⁸F-florbetapir in the brain lesions, along with a reduced Expanded Disability Status Scale score. Although only a small number of patients have been validated, this case first reported ¹⁸F-florbetapir PET/MRI could quantitatively and non-invasively assess the myelin recovery in GFAP-A patients, which may lead to improvements in the early diagnosis and long-term prognosis.

Case Report: Baló's Concentric Sclerosis-Like Lesion in a Patient With Relapsing-Remitting Multiple Sclerosis Treated With Dimethyl Fumarate

Baló's concentric sclerosis (BCS) is a rare demyelinating disorder characterized by acute or subacute neurological symptoms associated with characteristic lesions of concentric onion skin appearance on MRI images and in pathology. The connection between BCS and classic MS is still a subject of debates. Our report presents a case of a patient who developed a symptomatic Baló-like lesion following several years of classical relapsing-remitting multiple sclerosis treated with dimethyl fumarate.

The clinical spectrum of haemorrhagic CNS inflammatory demyelinating lesions

BACKGROUND

Haemorrhagic demyelinating lesions are rare, and little is known about the demyelinating diseases with which they are associated, or how lesional haemorrhage affects treatment and outcomes.

OBJECTIVE

To examine the clinical characteristics and outcomes of patients with demyelinating lesions and magnetic resonance imaging (MRI) evidence of haemorrhage seen at the Mayo clinic between 1990 and 2018.

METHODS

The Mayo Clinic's medical-record diagnostic-linkage system was used to identify patients with CNS demyelinating disease and parenchymal haemorrhage on brain MRI cross-referenced against a database of patients with pathologically confirmed CNS demyelinating disease. The clinical characteristics, diagnosis, MRI findings, brain histopathology, and outcomes of these patients were reviewed.

RESULTS

Ten patients with haemorrhagic demyelination were identified, including three patients who underwent a brain biopsy. The main findings were that haemorrhagic demyelinating lesions most often occur in atypical forms of demyelination, especially acute haemorrhagic leukoencephalitis (AHL, or Weston-Hurst disease) and tumefactive demyelination, and rarely in multiple sclerosis. A spectrum of outcomes was observed for these patients ranging from complete remission through to high level disability.

CONCLUSION

Lesional haemorrhage is uncommon in demyelinating disease where it is most closely associated with AHL. Bleeding within a demyelinating lesion does not always herald a poor prognosis.

Correlation between Amerindian ancestry and neuromyelitis optica spectrum disorders (NMSOD) among patients in Midwestern Brazil

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is the second most frequently demyelinating, autoimmune, and inflammatory Central Nervous System (CNS) disease, and its prevalence varies greatly according to geography and ethnicity.

OBJECTIVE

To determine the prevalence and phenotype of NMOSD at a reference center for demyelinating diseases in Goiás State.

METHODS

This was a cross-sectional study, approved under CAAE number 8380.9317.9.0000.5078. All patients fulfilled the 2015 international consensus criteria.

RESULTS

Our study showed NMOSD as 9.37% of all demyelinating diseases registered in. It occurred predominantly in women (81%) and non-white individuals (83.4% had self-declared mixed skin color), and the median age at onset was 48 years. Amerindian ancestry was significantly higher (68.75%) than others. Longitudinally extensive transverse myelitis (LETM) alone ≥3 vertebral segments (35%) and optic neuritis (ON) alone (35%) were the most common onset manifestations. The median length of time from disease beginning to study enrollment was 48 months. A relapsing course and moderate disability (Expanded Disability Status Scale (EDSS) 3.0-4.0) were most commonly observed. The worst neurological impairments, characterized by EDSS>4.5, occurred more frequently in males (44.5% among men versus 20.5% among women). The majority of the patients had been receiving immunosuppressive treatment with azathioprine since the diagnosis of NMSOD: 77% (37) had a good therapeutic response. The prevalent outcome (84%) was permanent disability: 52% became physically handicapped; 54% had permanent visual impairment (25% with bilateral and 75% with unilateral amaurosis) and 30% had sphincter disability (82% with neurogenic bladder and 18% with ostomy).

CONCLUSION

The estimated prevalence of NMOSD in Goiás is 0.79/per 100,000 inhabitants. The predominant phenotype comprises women, non-whites, onset in the fourth decade of life, relapsing course, and permanent moderate disability. Our study was the first on the epidemiology of NMOSD in Goiás, where NMOSD predominantly correlates with Amerindian ancestry.

Population-based incidence and clinico-radiological characteristics of tumefactive demyelination in Olmsted County, Minnesota, United States

BACKGROUND AND PURPOSE

Tumefactive demyelination (TD) presents with large inflammatory lesions mimicking tumors or other space-occupying lesions. Limited epidemiological, clinical and radiological data exist for TD. We aimed to report the incidence rate, and clinical and radiological features of TD in Olmsted County, Minnesota.

METHODS

We retrospectively reviewed patients with central nervous system inflammatory demyelination-related diagnostic codes (January 1, 1998 to December 31, 2018) in the Rochester Epidemiology Project database, and adjusted incidence rates by age and sex to the 2010 US total population. We used the Expanded Disability Status Scale (EDSS) to assess outcomes (index attack and last follow-up).

RESULTS

Of 792 multiple sclerosis (MS) patients, 15 (eight males, seven females) had tumefactive MS, representing 1.9% of the MS population. The median (range) age at attack onset was 34.2 (2-61) years. Tumefactive lesion was the first clinical MS attack in 8/16 patients. Cerebrospinal fluid oligoclonal bands (OCBs) were present in 8/12 patients and 11/16 patients met the Barkhof criteria for dissemination in space. Most patients remained fully ambulatory (EDSS score ≤4 in 13/16 patients [81%]) after a median (range) follow-up duration of 10.5 (1-20.5) years. Age-adjusted annual incidence rates were 0.46/100,000 (95% confidence interval [CI] 0.12-0.81) for female patients, 0.66/100,000 (95% CI 0.23-1.02) for male patients, and 0.56/100,000 [95% CI 0.28-0.83] overall. When age- and sex-adjusted to the 2010 US total population, the overall annual incidence rate was 0.57 (95% CI 0.28-0.84). Despite aggressive clinical presentation at disease onset, most patients remained fully ambulatory (EDSS score ≤4 in 13/16 patients) with a relapsing-remitting course.

CONCLUSIONS

Although incidence is rare, TD should be suspected in patients presenting with subacutely progressive neurological deficits associated with magnetic resonance imaging findings of ring enhancement, apparent diffusion coefficient restriction, and OCB on spinal fluid analysis.

Consensus recommendation on the use of therapeutic plasma exchange for adult neurological diseases in Southeast Asia from the Southeast Asia therapeutic plasma exchange consortium

Therapeutic plasma exchange (TPE) is an effective and affordable treatment option in most parts of Southeast Asia (SEA). In 2018, the SEA TPE Consortium (SEATPEC) was established, consisting of regional neurologists working to improve outcome of various autoimmune neurological diseases. We proposed an immunotherapeutic guideline prioritizing TPE for this region. We reviewed disease burden, evidence-based treatment options, and major guidelines for common autoimmune neurological disorders seen in SEA. A modified treatment algorithm based on consensus agreement by key-opinion leaders was proposed. Autoimmune antibody diagnostic testing through collaboration with accredited laboratories was established. Choice of first-line immunotherapies (IVIg/corticosteroid/TPE) is based on available evidence, clinicians’ experience, contraindications, local availability, and affordability. TPE could be chosen as first-line therapy for GBS, CIDP, MG (acute/short term), IgG, A paraproteinemic neuropathy, and NMDAR encephalitis. Treatment is stopped for acute monophasic conditions such as GBS and ADEM following satisfactory outcome. For chronic immune disorders, a therapy taper or long-term maintenance therapy is recommended depending on the defined clinical state. TPE as second-line treatment is indicated for IVIg or corticosteroids refractory cases of ADEM, NMOSD (acute), MG, and NMDAR/LGI1/CASPR2/Hashimoto’s encephalitis. With better diagnosis, treatment initiation with TPE is a sustainable and effective immunotherapy for autoimmune neurological diseases in SEA.

Encapsulation of bryostatin-1 by targeted exosomes enhances remyelination and neuroprotection effects in the cuprizone-induced demyelinating animal model of multiple sclerosis

Demyelination is a critical neurological disease, and there is still a lack of effective treatment methods. In the past two decades, stem cells have emerged as a novel therapeutic effector for neural regeneration. However, owing to the existence of the blood-brain barrier (BBB) and the complex microenvironment, targeted therapy still faces multiple challenges. Targeted exosome carriers for drug delivery may be considered a promising therapeutic method. Exosomes were isolated from mice neural stem cells. To develop targeting exosomes, we generated a lentivirus armed PDGFRα ligand that could anchor the membrane. Exosome targeting tests were carried out in vitro and in vivo. The modified exosomes showed an apparent ability to target OPCs in the lesion area. Next, the exosomes were loaded with Bryostatin-1 (Bryo), and the cuprizone-fed mice were administered with the targeting exosomes. The data show that Bryo exhibits a powerful therapeutic effect compared with Bryo alone after exosome encapsulation. Specifically, this novel exosome-based targeting delivery of Bryo significantly improves the protection ability of the myelin sheath and promotes remyelination. Moreover, it blocks astrogliosis and axon damage, and also has an inhibitory effect on pro-inflammatory microglia. The results of this investigation provide a straightforward strategy to produce targeting exosomes and indicate a potential therapeutic approach for demyelinating disease.

Diagnosis and Management of Central Nervous System Demyelinating Disorders

The spectrum of demyelinating diseases affecting the central nervous system is broad. Although many have a chronic course, neuroinflammatory conditions often present with acute to subacute onset symptoms requiring hospitalization when severe. This article reviews the acute phase assessment and management of these disorders, with a particular focus on multiple sclerosis, neuromyelitis optica spectrum disorder, myelin oligodendrocyte glycoprotein antibody disorder, and several atypical demyelinating diseases.

Tumefactive demyelination: updated perspectives on diagnosis and management

INTRODUCTION

Tumefactive demyelination (TD) can be a challenging scenario for clinicians due to difficulties distinguishing it from other conditions, such as neoplasm or infection; or with managing the consequences of acute lesions, and then deciding upon the most appropriate longer term treatment strategy.

AREAS COVERED

The authors review the literature regarding TD covering its clinic-radiological features, association with multiple sclerosis (MS), and its differential diagnosis with other neuroinflammatory and non-inflammatory mimicking disorders with an emphasis on atypical forms of demyelination including acute disseminated encephalomyelitis (ADEM), MOG antibody-associated demyelination (MOGAD) and neuromyelitis spectrum disorders (NMOSD). We also review the latest in the acute and long-term treatment of TD.

EXPERT OPINION

It is important that the underlying cause of TD be determined whenever possible to guide the management approach which differs between different demyelinating and other inflammatory conditions. Improved neuroimaging and advances in serum and CSF biomarkers should one day allow early and accurate diagnosis of TD leading to better outcomes for patients.

Fulminant inflammatory demyelination presenting as stroke-in-evolution in an elderly subject

BACKGROUND

Fulminant inflammatory demyelination is a possible presentation of inflammatory demyelinating disorders, thus representing a potential stroke mimic especially in younger patients.

AIMS OF THE STUDY

To describe clinical and diagnostic pitfalls in a case of fulminant inflammatory demyelination presenting with stroke-like symptoms in an elderly patient.

METHODS

Case report and case-based review of the literature.

RESULTS

A 67-year-old woman, who accessed the emergency room as suspect stroke for hyperacute onset of rapidly worsening speech impairment and drowsiness, was later diagnosed with a huge brain inflammatory demyelination. Clinical, laboratory, and neuroimaging tests did not allow to put a more specific diagnosis. Due to the rapidly deteriorating course, she received immunosuppression with benefit.

CONCLUSION

This report is meant to highlight the diagnostic challenges connected with fulminant inflammatory demyelination, which sometime can resemble a stroke-in evolution and appear clinically unfitting for inclusion in any specific pathological entities within the broad-spectrum of inflammatory demyelinating disorders.

Autoimmune Brainstem Encephalitis: An Illustrative Case and a Review of the Literature

Autoimmune brainstem encephalitis (BSE) is a rare neurological condition with a wide range of underlying etiologies. It can be subdivided into two broad groups: a primary inflammatory disease of the central nervous system (CNS) or a brainstem disorder secondary to systemic diseases where the CNS is only one of many affected organs. Symptoms range from mild to life-threatening manifestations. Most cases respond well to immunotherapy. Therefore, broad and in-depth knowledge of the various inflammatory disorders that target the brainstem is essential for guiding the diagnostic approach and assisting in early initiation of appropriate therapy. We herein report on a case of BSE and provide an overview of the various causes of autoimmune BSE with an emphasis on the clinical manifestations and diagnostic approach.

Pseudotumoral Demyelinating Lesions: A Presentation of Acute Disseminated Encephalomyelitis

Pseudotumoral forms of demyelination are related to central nervous system demyelinating disorders, usually considered to be an atypical presentation of multiple sclerosis including its different varieties such as Balo's, Schilder's, and Marburg diseases. These lesions could also be seen in myelin oligodendrocyte glycoprotein antibody-associated demyelination, acute disseminated encephalomyelitis (ADEM), and neuromyelitis optica spectrum disorder. The pseudotumoral aspect may be mistakenly considered as an abscess or a cancerous tumor, in which case, patients could endure unnecessary possibly harmful brain biopsy and have a delay in their disease diagnostics and management. Once latter differential diagnosis is discarded, pseudotumoral demyelination prompts uncertainties concerning the nature of the underlying demyelinating condition as prognosis and management differ from multiple sclerosis to other syndromes, especially whether a chronic treatment is needed or not. In this case report, we present a 35-year-old male patient hospitalized in the department of neurology for a rapidly progressive onset of encephalopathy and polyfocal neurological deficits, with pseudotumoral lesions shown on brain MRI. On further investigations, ADEM was the more likely diagnosis that could fit the patient's clinical and radiological presentation. Thence, he was put on high dose of intravenous corticosteroids, with a followed good recovery within the first week of the treatment.

Diagnostic approach in multiple sclerosis with MRI: an update

Although neurological examination and medical history are the first and most important steps towards the diagnosis of multiple sclerosis (MS), MRI has taken a prominent role in the diagnostic workflow especially since the implementation of McDonald criteria. However, before applying those on MR imaging features, other diseases must be excluded and MS should be favoured as the most likely diagnosis. For the prognosis the earliest possible and correct diagnosis of MS is crucial, since increasingly effective disease modifying therapies are available for the different forms of clinical manifestation and progression. This review deals with the significance of MRI in the diagnostic workup of MS with special regard to daily clinical practice. The recommended MRI protocols for baseline and follow-up examinations are summarized and typical MS lesion patterns ("green flags") in four defined CNS compartments are introduced. Pivotal is the recognition of neurological aspects as well as imaging findings atypical for MS ("red flags"). In addition, routinely assessment of Aquaporin-4-IgG antibodies specific for neuromyelitis optica spectrum disorders (NMOSD) as well as the knowledge of associated lesion patterns on MRI is recommended. Mistaken identity of such lesions with MS and consecutive implementation of disease modifying therapies for MS can worsen the course of NMOSD.

A Review of Clinical and Imaging Findings in Tumefactive Demyelination

OBJECTIVE. Tumefactive demyelination mimics primary brain neoplasms on imaging, often necessitating brain biopsy. This article reviews the literature for the clinical and radiologic findings of tumefactive demyelination in various disease processes to facilitate identification of tumefactive demyelination on imaging. CONCLUSION. Both clinical and radiologic findings must be integrated to distinguish tumefactive demyelinating lesions from similarly appearing lesions on imaging. Further research on the immunopathogenesis of tumefactive demyelination and associated conditions will elucidate their interrelationship.

Clinical and Radiologic Features, Pathology, and Treatment of Baló Concentric Sclerosis

OBJECTIVE

To describe clinical, radiologic, and pathologic features of Baló concentric sclerosis (BCS) and assess overlap between BCS and other CNS inflammatory demyelinating diseases.

METHODS

Retrospective review of BCS cases from US and Australian tertiary care centers.

RESULTS

We identified 40 BCS cases with 38 available MRIs. Solitary MRI lesions were present in 26% (10/38). We saw >1 active concurrent BCS lesion in 45% (17/38). A third (13/38) had multiple sclerosis-suggestive lesions on the index MRI, of which 10 fulfilled Barkhof criteria. In patients with serial MRI performed within 1 month of the index MRI, lesions expanded radially with sequentially increased numbers of T2 hyperintense rings 52% (14/27). Initially nonenhancing or centrally enhancing lesions subsequently developed single or multiple enhancing rings (41%; 9/22) and incomplete enhancing rings (14%; 3/22). Discordance between rings as they appear on apparent diffusion coefficient, diffusion-weighted imaging, and gadolinium-enhanced imaging was observed in 67% (22/33). Aquaporin-4 immunoglobulin G (n = 26) and myelin oligodendrocyte glycoprotein immunoglobulin G (n = 21) were negative in all patients with serum available. Clinical response to steroid treatment was seen in 46% (13/28). A monophasic clinical course was present in 56% (18/32) at last follow-up (median 27.5 months; range 3-100 months). The initial attack was fatal in 10% (4/40). Median time from symptom onset to death was 23 days (range 19-49 days). All 17 patients with pathology available demonstrated typical findings of multiple sclerosis. Patients with active demyelinating lesions all demonstrated oligodendrocytopathy (pattern III).

CONCLUSIONS

BCS may be a distinct subtype of multiple sclerosis characterized by pattern III immunopathology.

Clinico-radiologic features and therapeutic strategies in tumefactive demyelination: a retrospective analysis of 50 consecutive cases

Aims

Our goal was to expand the spectrum of clinico-radiologic characteristics and the possible therapeutic choices in patients with tumefactive demyelinating lesions (TDLs).

Methods

A retrospective analysis of 50 patients with at least one TDL was performed at an academic neurology center (2008-2020).

Results

Our cohort comprised mostly women (33/50) with a mean age of 38 years at TDL onset. The mean follow-up time was 76 months. The mean Expanded Disability Status Scale score at TDL onset and at the latest neurological evaluation was 3.7 and 2.3, respectively. We subcategorized the patients into seven groups based mainly on the clinical/radiological findings and disease course. Group A included patients presenting with a Marburg-like TDL (n = 4). Groups B and C comprised patients presenting with monophasic (n = 7) and recurrent TDLs (n = 12), respectively. Multiple sclerosis (MS) patients who subsequently developed TDL (n = 16) during the disease course were categorized as Group D. Group E comprised patients who initially presented with TDL and subsequently developed a classical relapsing-remitting MS without further evidence of TDL (n = 5). Groups F (n = 2) and G (n = 4) involved MS patients who developed TDL during drug initiation (natalizumab, fingolimod) and cessation (interferon, fingolimod), respectively. Regarding long-term treatments applied after corticosteroid administration in the acute phase, B-cell-directed therapies were shown to be highly effective especially in cases with recurrent TDLs. Cyclophosphamide was spared for more aggressive disease indicated by a poor response to corticosteroids and plasma exchange failure.

Conclusion

Tumefactive central nervous system demyelination is an heterogenous disease; its stratification into distinct groups according to different phenotypes can establish more efficient treatment strategies, thus improving clinical outcomes in the future.

Autoimmune Neurologic Emergencies

Over the past decade, understanding of autoimmune neurologic disorders has exponentially increased. Many patients present as a neurologic emergency and require timely evaluation with rapid management and intensive care. However, the diagnosis is often either missed or delayed, which may lead to a significant burden of disabling morbidity and even mortality. A high level of suspicion in the at-risk population should be maintained to facilitate more rapid diagnosis and prompt treatment. At present, there is no all-encompassing algorithm specifically applicable to the management of fulminant autoimmune neurologic disorders. This article discusses manifestations and management of various autoimmune neurologic emergencies.

Spinal Cord Anatomy and Localization

PURPOSE OF REVIEW

This article focuses on clinically relevant teaching points in spinal anatomy and localizing the lesion in myelopathy.

RECENT FINDINGS

The principles underlying spinal cord lesion localization are well established, but improvements in MRI and the discovery of pathologic antibodies associated with causes of transverse myelitis distinct from multiple sclerosis, such as aquaporin-4 IgG and myelin oligodendrocyte glycoprotein IgG, have assisted in diagnosis.

SUMMARY

The spinal cord has a highly organized neuroanatomy of ascending and descending tracts that convey sensory, motor, and autonomic information. Using integration of clues from the patient's history and neurologic examination, the effective clinician can distinguish spinal cord from peripheral nerve or brain pathology, often determine the level and parts of the spinal cord affected by a lesion, and focus on a likely diagnosis. The advent of MRI of the spine has revolutionized investigation of spinal cord disorders, but an important place for strong clinical acumen still exists in assessing the patient with a myelopathy.

Differential imaging of atypical demyelinating lesions of the central nervous system

The detection of atypical and sometimes aggressive or tumefactive demyelinating lesions of the central nervous system often poses difficulties in the differential diagnosis. The clinical presentation is generally aspecific, related to the location and similar to a number of different lesions, including neoplasms and other intracranial lesions with mass effect. CSF analysis may also be inconclusive, especially for lesions presenting as a single mass at onset. As a consequence, a brain biopsy is frequently performed for characterization. Advanced MRI imaging plays an important role in directing the diagnosis, reducing the rate of unnecessary biopsies and allowing a prompt start of therapy that is often crucial, especially in the case of infratentorial lesions. In this review, the main pattern of presentation of atypical inflammatory demyelinating diseases is discussed, with particular attention on the differential diagnosis and how to adequately define the correct etiology.