Acute Disseminated Encephalomyelitis and Acute Hemorrhagic Leukoencephalitis Following COVID-19: Systematic Review and Meta-synthesis.

BACKGROUND AND OBJECTIVES: Since the onset of the COVID-19 pandemic, a growing number of reports have described cases of acute disseminated encephalomyelitis (ADEM) and acute hemorrhagic leukoencephalitis (AHLE) following infection with COVID-19. Given their relatively rare occurrence, the primary objective of this systematic review was to synthesize their clinical features, response to treatments, and clinical outcomes to better understand the nature of this neurologic consequence of COVID-19 infection. METHODS: Patients with a history of COVID-19 infection were included if their reports provided adequate detail to confirm a diagnosis of ADEM or AHLE by virtue of clinical features, radiographic abnormalities, and histopathologic findings. Cases purported to be secondary to vaccination against COVID-19 or occurring in the context of a preexisting relapsing CNS demyelinating disease were excluded. Case reports and series were identified via PubMed on May 17, 2021, and 4 additional cases from the authors' hospital files supplemented the systematic review of the literature. Summary statistics were used to describe variables using a complete case analysis approach. RESULTS: Forty-six patients (28 men, median age 49.5 years, 1/3 >50 years old) were analyzed, derived from 26 case reports or series originating from 8 countries alongside 4 patient cases from the authors' hospital files. COVID-19 infection was laboratory confirmed in 91% of cases, and infection severity necessitated intensive care in 67%. ADEM occurred in 31 cases, whereas AHLE occurred in 15, with a median presenting nadir modified Rankin Scale score of 5 (bedridden). Anti-MOG seropositivity was rare (1/15 patients tested). Noninflammatory CSF was present in 30%. Hemorrhage on brain MRI was identified in 42%. Seventy percent received immunomodulatory treatments, most commonly steroids, IV immunoglobulins, or plasmapheresis. The final mRS score was ≥4 in 64% of patients with adequate follow-up information, including 32% who died. DISCUSSION: In contrast to ADEM cases from the prepandemic era, reported post-COVID-19 ADEM and AHLE cases were often advanced in age at onset, experienced severe antecedent infection, displayed an unusually high rate of hemorrhage on neuroimaging, and routinely had poor neurologic outcomes, including a high mortality rate. Findings are limited by nonstandardized reporting of cases, truncated follow-up information, and presumed publication bias.

Postvaccinal Encephalitis after ChAdOx1 nCov-19.

The global SARS-CoV-2 pandemic has contributed to more than 163 million confirmed infections and 3.3 million deaths worldwide. The severity of the pandemic has led to an unprecedented effort to develop multiple effective vaccines. Due to excellent safety and efficacy data from clinical trials, several vaccines were approved. We report a case series of postvaccinal encephalitis in temporal correlation to vaccination with ChAdOx1 nCov-19. The diagnostic criteria for possible autoimmune encephalitis were fulfilled. Our patients responded well to immunosuppressive therapy with corticosteroids. The incidence has been estimated to be approximately 8 per 10 million vaccine doses. Complication of postvaccinal encephalitis after ChAdOx1 nCoV-19 vaccination still appear to be very rare, but need to be diagnosed and treated adequately. Large pooled data from observational epidemiologic studies are necessary to verify causality. ANN NEUROL 2021;90:506-511.

Clinical Features, Treatment Strategies, and Outcomes in Hospitalized Children With Immune-Mediated Encephalopathies.

BACKGROUND: Autoimmune encephalitis (AE) and acute disseminated encephalomyelitis (ADEM) are immune-mediated brain conditions that can cause substantial neurological sequalae. Data describing the clinical characteristics, treatments, and neurological outcomes for these conditions are needed. METHODS: This is a single-center retrospective review of children diagnosed with AE or ADEM over a nine-year period with discharge outcomes measured by the Modified Rankin Score. RESULTS: Seventy-five patients (23 with ADEM and 52 with AE) were identified. Patients with ADEM had a higher percentage of abnormal magnetic resonance imaging findings (100% vs 60.8%; P < 0.001) and a shorter time from symptom onset to diagnosis (6 vs 14 days; P = 0.024). Oligoclonal bands and serum and cerebrospinal fluid inflammatory indices were higher in patients with AE. Nearly all patients received corticosteroids followed by plasmapheresis or intravenous immunoglobulin, and treatment strategies did not differ significantly between groups. Second-line immune therapies were commonly used in patients with AE. Finally, patients with AE had trends toward longer hospital lengths of stay (21 vs 13 days) and a higher percentage of neurological disability at hospital discharge (59.6% vs 34.8%). CONCLUSIONS: Although patients with ADEM and AE may have similar presenting symptoms, we found significant differences in the frequency of imaging findings, symptom duration, and laboratory and cerebrospinal fluid profiles, which can assist in distinguishing between the diagnoses. Patients in both groups were treated with a combination of immunomodulating therapies, and neurological disability was common at hospital discharge.

Neuroimaging manifestations in children with SARS-CoV-2 infection: a multinational, multicentre collaborative study.

BACKGROUND: The CNS manifestations of COVID-19 in children have primarily been described in case reports, which limit the ability to appreciate the full spectrum of the disease in paediatric patients. We aimed to identify enough cases that could be evaluated in aggregate to better understand the neuroimaging manifestations of COVID-19 in the paediatric population. METHODS: An international call for cases of children with encephalopathy related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and abnormal neuroimaging findings was made. Clinical history and associated plasma and cerebrospinal fluid data were requested. These data were reviewed by a central neuroradiology panel, a child neurologist, and a paediatric infectious diseases expert. The children were categorised on the basis of their time of probable exposure to SARS-CoV-2. In addition, cases were excluded when a direct link to SARS-CoV-2 infection could not be established or an established alternate diagnostic cause could be hypothesised. The accepted referral centre imaging data, from ten countries, were remotely reviewed by a central panel of five paediatric neuroradiologists and a consensus opinion obtained on the imaging findings. FINDINGS: 38 children with neurological disease related to SARS-CoV-2 infection were identified from France (n=13), the UK (n=8), the USA (n=5), Brazil (n=4), Argentina (n=4), India (n=2), Peru (n=1), and Saudi Arabia (n=1). Recurring patterns of disease were identified, with neuroimaging abnormalities ranging from mild to severe. The most common imaging patterns were postinfectious immune-mediated acute disseminated encephalomyelitis-like changes of the brain (16 patients), myelitis (eight patients), and neural enhancement (13 patients). Cranial nerve enhancement could occur in the absence of corresponding neurological symptoms. Splenial lesions (seven patients) and myositis (four patients) were predominantly observed in children with multisystem inflammatory syndrome. Cerebrovascular complications in children were less common than in adults. Significant pre-existing conditions were absent and most children had favourable outcomes. However, fatal atypical CNS co-infections developed in four previously healthy children infected with SARS-CoV-2. INTERPRETATION: Acute-phase and delayed-phase SARS-CoV-2-related CNS abnormalities are seen in children. Recurring patterns of disease and atypical neuroimaging manifestations can be found and should be recognised being as potentially due to SARS-CoV-2 infection as an underlying aetiological factor. Studies of paediatric specific cohorts are needed to better understand the effects of SARS-CoV-2 infection on the CNS at presentation and on long-term follow-up in children. FUNDING: American Society of Pediatric Neuroradiology, University of Manchester (Manchester, UK). VIDEO ABSTRACT.

Silent New Brain MRI Lesions in Children with MOG-Antibody Associated Disease.

Anti-myelin oligodendrocyte glycoprotein immunoglobulin G (MOG-IgG) antibodies are associated clinically with either a monophasic or relapsing disease course. We investigated the frequency and clinical importance of acquired asymptomatic brain magnetic resonance imaging (MRI) lesions in a prospective incident cohort of 74 MOG-IgG positive children with serial MRI scans over a median of 5 years from presentation. Silent new lesions were detected in 14% of MOG-IgG positive participants, most commonly within the first months post-onset, with a positive predictive value for clinically relapsing disease of only 20%. Detection of asymptomatic lesions alone need not prompt initiation of chronic immunotherapy. ANN NEUROL 2021;89:408-413.

Epidemiology of Demyelinating Diseases in Korean Pediatric Patients.

The epidemiology of demyelinating diseases in the Korean pediatric population has not been reported to date. This study aimed to identify the epidemiology of demyelinating diseases in Korean children by using big data. The subjects were children (0-17 years old) diagnosed with acute-disseminated encephalomyelitis, multiple sclerosis, neuromyelitis optica, and Guillain-Barré syndrome enrolled in the Korean Health Insurance Review and Assessment Service (HIRA) from January 2010 to December 2017.Of 1722 enrolled children, 553 (32.1%) had acute-disseminated encephalomyelitis, 170 (9.9%) had multiple sclerosis, 68 (3.9%) had neuromyelitis optica, and 931 (54.1%) had Guillain-Barré syndrome. The male-female ratios were 1.47:1 in acute-disseminated encephalomyelitis, 1.43:1 in Guillain-Barré syndrome, 1:1.66 in multiple sclerosis, and 1:1.62 in neuromyelitis optica. Demyelinating diseases were most prevalent in summer. The prevalence differed by region, with 545 (31.6%) in Seoul and 298 (17.3%) in Gyeonggi. This study is the first to identify the incidence of demyelinating diseases in South Korea.

Spectrum of Neurological Manifestations in Covid-19: A Review.

COVID-19, in most patients, presents with mild flu-like illness. Elderly patients with comorbidities, like hypertension, diabetes, or lung and cardiac disease, are more likely to have severe disease and deaths. Neurological complications are frequently reported in severely or critically ill patients with comorbidities. In COVID-19, both central and peripheral nervous systems can be affected. The SARS-CoV-2 virus causes the disease COVID-19 and has the potential to invade the brain. The SARS-CoV-2 virus enters the brain either via a hematogenous route or olfactory system. Angiotensin-converting enzyme two receptors, present on endothelial cells of cerebral vessels, are a possible viral entry point. The most severe neurological manifestations, altered sensorium (agitation, delirium, and coma), are because of hypoxic and metabolic abnormalities. Characteristic cytokine storm incites severe metabolic changes and multiple organ failure. Profound coagulopathies may manifest with ischemic or hemorrhagic stroke. Rarely, SARS-CoV-2 virus encephalitis or pictures like acute disseminated encephalomyelitis or acute necrotizing encephalopathy have been reported. Nonspecific headache is a commonly experienced neurological symptom. A new type of headache "personal protection equipment-related headache" has been described. Complete or partial anosmia and ageusia are common peripheral nervous system manifestations. Recently, many cases of Guillain-Barré syndrome in COVID-19 patients have been observed, and a postinfectious immune-mediated inflammatory process was held responsible for this. Guillain-Barré syndrome does respond to intravenous immunoglobulin. Myalgia/fatigue is also common, and elevated creatine kinase levels indicate muscle injury. Most of the reports about neurological complications are currently from China. COVID-19 pandemic is spreading to other parts of the world; the spectrum of neurological complications is likely to widen further.

Acute Disseminated Encephalomyelitis with Seizures and Myocarditis: A Fatal Triad.

Autoimmune pathology of acute disseminated encephalomyelitis (ADEM) is generally restricted to the brain. Our objective is to expand the phenotype of ADEM. A four-year-old girl was admitted to the pediatric emergency room of a university medical center five days after a common upper respiratory tract infection. Acute symptoms were fever, leg pain, and headaches. She developed meningeal signs, and her level of consciousness dropped rapidly. Epileptic seizure activity started, and she became comatose, requiring intubation and mechanical ventilation. Serial brain magnetic resonance imaging (MRI) illustrated the fulminant development of ADEM. Treatment escalation with high-dose corticosteroids, immunoglobulins, and plasma exchange did not lead to clinical improvement. On day ten, the patient developed treatment-refractory cardiogenic shock and passed away. The postmortem assessment confirmed ADEM and revealed acute lymphocytic myocarditis, likely explaining the acute cardiac failure. Human metapneumovirus and picornavirus were detected in the tracheal secrete by PCR. Data sources-medical chart of the patient. This case is consistent with evidence from experimental findings of an association of ADEM with myocarditis as a postinfectious systemic autoimmune response, with life-threatening involvement of the brain and heart.

COVID-19: A Global Threat to the Nervous System.

In less than 6 months, the severe acute respiratory syndrome-coronavirus type 2 (SARS-CoV-2) has spread worldwide infecting nearly 6 million people and killing over 350,000. Initially thought to be restricted to the respiratory system, we now understand that coronavirus disease 2019 (COVID-19) also involves multiple other organs, including the central and peripheral nervous system. The number of recognized neurologic manifestations of SARS-CoV-2 infection is rapidly accumulating. These may result from a variety of mechanisms, including virus-induced hyperinflammatory and hypercoagulable states, direct virus infection of the central nervous system (CNS), and postinfectious immune mediated processes. Example of COVID-19 CNS disease include encephalopathy, encephalitis, acute disseminated encephalomyelitis, meningitis, ischemic and hemorrhagic stroke, venous sinus thrombosis, and endothelialitis. In the peripheral nervous system, COVID-19 is associated with dysfunction of smell and taste, muscle injury, the Guillain-Barre syndrome, and its variants. Due to its worldwide distribution and multifactorial pathogenic mechanisms, COVID-19 poses a global threat to the entire nervous system. Although our understanding of SARS-CoV-2 neuropathogenesis is still incomplete and our knowledge is evolving rapidly, we hope that this review will provide a useful framework and help neurologists in understanding the many neurologic facets of COVID-19. ANN NEUROL 2020;88:1-11 ANN NEUROL 2020;88:1-11.

The clinical spectrum and incidence of anti-MOG-associated acquired demyelinating syndromes in children and adults.

OBJECTIVES: The aim of this study was to assess the Dutch nationwide incidence of myelin oligodendrocyte glycoprotein (MOG)-IgG-associated acquired demyelinating syndromes (ADS) and to describe the clinical and serological characteristics of these patients. METHODS: All serum samples for routine diagnostics from February 2014 to December 2017 were sent to the single central reference laboratory for the full-length MOG-IgG cell-based assay (CBA) in the Netherlands. Clinical data from patients known in our National ADS centre were available. RESULTS: A total of 1414 samples of 1277 patients were received; of these, 92 patients (7%) were MOG-IgG-seropositive. The mean incidence was 0.16/100,000 people, with higher seropositivity in children (0.31/100,000) than in adults (0.13/100,000). In MOG-IgG-positive patients at the National ADS centre (61/92, 66%), the most common presenting phenotype is acute disseminated encephalomyelitis (ADEM, 56%) in children and optic neuritis (ON, 44%) in adults. Relapsing disease occurred in 9/34 (26%) children and 11/27 (41%) adults during median follow-up of 27.5 months. Patients were tested MOG-IgG-positive >200 months after the initial attack, suggesting an extended time to first relapse (TTFR). Longitudinal analysis of MOG-IgG (25/61, 41%) showed that 67% of the monophasic patients remain seropositive and 60% in relapsing patients. Majority of seronegative patients had no relapses (89%). CONCLUSION: This nationwide study shows that the overall incidence of MOG-IgG-seropositive disorders is 0.16 per 100,000 people. The distribution over the clinical phenotypes differs between adults and children. Seropositivity can be maintained over years even without clinical activity, while seronegative patients generally had no relapses.

Early predictors of epilepsy and subsequent relapse in children with acute disseminated encephalomyelitis.

OBJECTIVE: To identify predictors of epilepsy and clinical relapses in children presenting with acute disseminated encephalomyelitis (ADEM). METHODS: Children presenting with ADEM between 2005 and 2017 and tested clinically for MOG-Ab were identified from three tertiary paediatric neurology centres in the United Kingdom. Patients were followed up for a median of 6 years (range, 1-16 years). RESULTS: A total of 74 children were studied (38 females; median age at first presentation: 4.5 years (range, 1.4-16 years)). MOG-Ab was positive in 50/74 (67.6%) of cases, and 27 (54%) of MOG-Ab positive children presented with a neurological relapse over time. MOG-Ab was more frequently positive in the relapsing group than in the monophasic group (27/31 vs 23/43; odds ratio 5.9 (95% CI: 1.8-19.7); p = 0.002). 16/74 (22%) children had seizures during the acute presentation with ADEM and 12/74 (16.2%) patients were diagnosed with post-ADEM epilepsy. The diagnosis of post-ADEM epilepsy was more frequently observed in children with relapsing disease than monophasic disease (10/31 vs 2/43; odds ratio 9.8 (95% confidence interval (CI): 2.0-48.7); p = 0.003), in children who had positive intrathecal oligoclonal bands than those with negative bands (4/7 vs 4/30; odds ratio 8.7 (95% CI: 1.4-54.0); p = 0.027) and in children who had positive MOG-Ab than negative MOG-Ab cases (11/12 vs 39/62; odds ratio 6.5 (95% CI:0.8-53.6); p = 0.051). CONCLUSION: A higher relapse rate and a greater risk of post-ADEM epilepsy in children with MOG-Ab-associated disease may indicate a chronic disease with immune-mediated seizures in these children.

Whole exome sequencing in a child with acute disseminated encephalomyelitis, optic neuritis, and periodic fever syndrome: a case report.

BACKGROUND: Acute disseminated encephalomyelitis is generally preceded by an infection, and it is usually self-limiting and non-recurrent. However, when there are multiple attacks of acute disseminated encephalomyelitis followed by optic neuritis, it is defined as acute disseminated encephalomyelitis-optic neuritis. To the best of our knowledge, there are no previous reports of acute disseminated encephalomyelitis and optic neuritis preceded by autoinflammation, triggered by periodic fever syndrome. We report on a case of acute disseminated encephalomyelitis with optic neuritis and periodic fever syndrome in a 12-year-old Ecuadorian Hispanic boy with several relapses over the past 10 years, always preceded by autoinflammatory manifestations and without evidence of infectious processes. Whole exome sequencing was performed, and although the results were not conclusive, we found variants in genes associated with both autoinflammatory (NLRP12) and neurological (POLR3A) phenotypes that could be related to the disease pathogenesis having a polygenic rather than monogenic trait. CONCLUSION: We propose that an autoinflammatory basis should be pursued in patients diagnosed as having acute disseminated encephalomyelitis and no record of infections. Also, we show that our patient had a good response after 1 year of treatment with low doses of intravenous immunoglobulin and colchicine.

[Imaging appearance of acute disseminated encephalomyelitis: a study of 22 cases]. / Imagerie de l'encéphalomyélite aiguë disséminée: étude de 22 cas.

Acute disseminated encephalomyelitis (ADEM) is a rare cause of encephalitis in adults, characterized by inflammatory lesions in the white substance of the central nervous system (CNS). Initial clinical presentation may mimic severe CNS infection with fever, encephalopathy, seizures, or multiple sclerosis. The purpose of our study was to report the epidemiological, clinical, radiological, therapeutic and evolutionary features of ADEM and to determine the role of MRI sequences in the diagnosis, monitoring and prognosis of this disease. We conducted a retrospective study of the clinical and radiological records of 22 patients with ADEM followed up in the Department of Neurology over a period of 11 years (January 2006- January 2017). These patients underwent medical imaging at the Mohammed V Military Teaching Hospital, de Rabat. The average age of patients was 35 years (12-57 years). A recent infection was found in 31% of patients, while 4% of patients had recently undergone vaccination. Symptoms were dominated by focal neurologic deficit (72%). CT scan was normal in 78%. MRI showed hyperintense subtentorial and supratentorial white substance on FLAIR sequences in 70% of patients, without diffusion restriction in all cases, with enhancement of the lesions in 27% of cases and involvement of the cervical spinal cord in 68% of cases. Clinical and radiological outcome was favorable in all cases.

A unique case of multiphasic ADEM or what else?

BACKGROUND: Acute disseminated encephalomyelitis (ADEM) is a monophasic post-infectious demyelinating disease, clinically defined by the acute onset of polyfocal neurological deficits including encephalopathy. A subset of ADEM patients will subsequently be diagnosed with relapsing disorders, including recurrent DEM (RDEM), multiphasic DEM (MDEM), neuromyelitis optica spectrum disorders (NMOSD) and multiple sclerosis (MS). Here we describe the case of an adult patient, who presented two ADEM-like episodes after a very long (8 years) symptoms-free period. CLINICAL CASE: A 48 years old man presented a first case of sub-acute onset of encephalopathy and dysarthria with MRI findings suggestive for ADEM for which he underwent an intravenous and oral steroid treatment followed by a complete clinical remission. After 8 years he presented a new sub-acute onset of encephalopathy and balance disorders with the onset of new lesions at the MRI. The search for oligoclonal band (OCB) showed a single CSF-restricted IgG band. Suspecting a new ADEM episode he was treated with intravenous steroids without benefit and 3 apheresis sessions with clinical improvement followed by an oral steroid treatment. After 2 months he experienced a paroxysmal episode of dysarthria, upper and lower left limbs impairment and urge incontinence with a stable new brain and spinal cord MRI. The search for anti-aquaporin-4 and anti-MOG (cell-based assay) antibodies was repeated twice within a 6 months span and resulted in both cases negative. The patient was treated with Rituximab (1g followed by 1g after 15 days, followed by 1g after 6 months) with stability of the neurological and radiological examinations at the last follow-up. CONCLUSIONS: To the best of our knowledge, this is the first case of MDEM in which the two episodes of ADEM occurred 8 years apart. Although this case fulfills the diagnostic criteria for MDEM, the time elapsed between the two episodes is very long. Therefore, we cannot exclude that this disease might be a new nosological entity that could be included in the expanding range of demyelinating diseases.

Acute disseminated encephalomyelitis in children - clinical and MRI decision making in the emergency department.

BACKGROUND: Acute disseminated encephalomyelitis (ADEM) is an uncommon, treatable, primarily pediatric, immune-mediated disease. Diagnosis of ADEM requires two essential elements: typical clinical presentation and magnetic resonance imaging (MRI) findings. The aim of this study was to evaluate how clinical findings in the initial emergency department (ED) presentation influenced the timing of MRI. METHODS: A retrospective chart review was conducted of children diagnosed with ADEM, over a 12-year period, in a tertiary care pediatric center. Clinical presentation at ED admission was recorded and patients who underwent an MRI as part of their ED evaluation (early MRI) with those who had MRI performed during ward hospitalization (late MRI) were compared. RESULTS: 30 patients were diagnosed with ADEM during the study period. Encephalopathy and polyfocal neurological signs were described in 80% and 50% of patients ED charts, respectively. Seven patients underwent early MRI and polyfocal neurological signs were more common in this group (p = 0.006). Fever was more common in the late MRI group (p = 0.02). Following diagnosis, all patients were treated with immune-modulation therapy, improved clinically, and were discharged. CONCLUSION: 20% of ADEM patients were not encephalopathic at ED presentation. Polyfocal neurological signs and absence of fever at ED presentation were related to earlier MRI utilization and thus earlier diagnosis and treatment. Familiarity with the ADEM constellation of signs, and a high index of suspicion, may help the ED clinician in early diagnosis and treatment of this rare disease.

Clinical time course of pediatric acute disseminated encephalomyelitis.

The detailed clinical time course in acute disseminated encephalomyelitis (ADEM) from initial symptoms, through exacerbation, to remission has not been widely reported. Hence, this study aimed to investigate the clinical time course of pediatric ADEM. This was a multicenter retrospective study based on registry data from medical chart reviews. The study included children who met the international consensus diagnostic criteria for ADEM. The patients comprised 18 boys and 6 girls, with a mean age of 5.5 ±â€¯3.3 years at onset. From onset, the time until peak neurological symptoms, time until initial improvement, and time until full recovery was 3.1 ±â€¯3.7 days, 6.0 ±â€¯4.5 days, and 26 ±â€¯34 days, respectively. Twenty-three (96%) patients were treated with high-dose methylprednisolone (mPSL) with a mean duration of 4.1 ±â€¯4.0 days from onset. The condition of 15 patients (65%) improved within 3 days of high-dose mPSL initiation, whereas, that of four patients began to improve after >5 days of high-dose mPSL initiation. Only one patient (4%) did not achieve full recovery despite treatment with high-dose mPSL, intravenous immunoglobulin, and plasma exchange. This study presents the detailed clinical time course in pediatric ADEM in Japan. Progression of neurologic deficits typically lasts a few days, with initial improvement in 1 week leading to full recovery within 1 month.

Development of the clinical assessment scale in autoimmune encephalitis.

OBJECTIVE: There is no scale for rating the severity of autoimmune encephalitis (AE). In this study, we aimed to develop a novel scale for rating severity in patients with diverse AE syndromes and to verify the reliability and validity of the developed scale. METHODS: The key items were generated by a panel of experts and selected according to content validity ratios. The developed scale was initially applied to 50 patients with AE (development cohort) to evaluate its acceptability, reproducibility, internal consistency, and construct validity. Then, the scale was applied to another independent cohort (validation cohort, n = 38). RESULTS: A new scale consisting of 9 items (seizure, memory dysfunction, psychiatric symptoms, consciousness, language problems, dyskinesia/dystonia, gait instability and ataxia, brainstem dysfunction, and weakness) was developed. Each item was assigned a value of up to 3 points. The total score could therefore range from 0 to 27. We named the scale the Clinical Assessment Scale in Autoimmune Encephalitis (CASE). The new scale showed excellent interobserver (intraclass correlation coefficient [ICC] = 0.97) and intraobserver (ICC = 0.96) reliability for total scores, was highly correlated with modified Rankin scale (r = 0.86, p < 0.001), and had acceptable internal consistency (Cronbach α = 0.88). Additionally, in the validation cohort, the scale showed high interobserver reliability (ICC = 0.99) and internal consistency (Cronbach α = 0.92). INTERPRETATION: CASE is a novel clinical scale for AE with a high level of clinimetric properties. It would be suitable for application in clinical practice and might help overcome the limitations of current outcome scales for AE. ANN NEUROL 2019;85:352-358.

Increased Intracranial Pressure in Acute Disseminated Encephalomyelitis.

OBJECTIVE: To assess the intracranial pressure in pediatric acute disseminated encephalomyelitis using spinal tap opening pressure on lumbar puncture, which is routinely performed as part of suspected acute disseminated encephalomyelitis workup. Compared to other cerebrospinal fluid parameters such as cell count, protein concentration, and presence of oligoclonal bands, cerebrospinal fluid opening pressure is infrequently recorded. METHODS: A retrospective chart review of demographic, clinical, and laboratory data of children diagnosed with acute disseminated encephalomyelitis admitted to a tertiary referral hospital between 2005 and 2016. RESULTS: Of the 36 children diagnosed with acute disseminated encephalomyelitis, 24 had the cerebrospinal fluid opening pressure documented in their records. The mean cerebrospinal fluid opening pressure was 27.6±12.6 cmH2O, range 9-55 cmH2O (95% confidence interval 21.9-33.6). Cerebrospinal fluid opening pressure in the acute disseminated encephalomyelitis group was statistically significantly higher ( P = .0013, 95% confidence interval 4.2-15.0) than the accepted upper limit in this age group (18 cmH2O). In 10 of 24 patients (42%), the opening pressure was above 28 cmH2O. CONCLUSIONS: Increased opening pressure was the most frequent cerebrospinal fluid abnormal finding in our cohort, which suggests a potential role of increased intracranial pressure in the acute disseminated encephalomyelitis pathophysiological disease mechanism. In certain cases, the opening pressure value could have monitoring and therapeutic implications, and therefore its measurement is highlighted by this study.