Diagnostic markers of acute encephalitis syndrome and COVID-associated multisystem inflammatory syndrome in children from Southern India

Acute encephalitis syndrome (AES) in children poses a significant public health challenge in India. This study aims to explore the utility of host inflammatory mediators and neurofilament (NfL) levels in distinguishing etiologies, assessing disease severity, and predicting outcomes in AES. We assessed 12 mediators in serum (n = 58) and 11 in cerebrospinal fluid (CSF) (n = 42) from 62 children with AES due to scrub typhus, viral etiologies, and COVID-associated multisystem inflammatory syndrome (MIS-C) in Southern India. Additionally, NfL levels in serum (n = 20) and CSF (n = 18) were examined. Clinical data, including Glasgow coma scale (GCS) and Liverpool outcome scores, were recorded. Examining serum and CSF markers in the three AES etiology groups revealed notable distinctions, with scrub typhus differing significantly from viral and MIS-C causes. Viral causes had elevated serum CCL11 and CCL2 compared with scrub typhus, while MIS-C cases showed higher HGF levels than scrub typhus. However, CSF analysis showed a distinct pattern with the scrub typhus group exhibiting elevated levels of IL-1RA, IL-1β, and TNF compared with MIS-C, and lower CCL2 levels compared with the viral group. Modeling the characteristic features, we identified that age ≥3 years with serum CCL11 < 180 pg/mL effectively distinguished scrub typhus from other AES causes. Elevated serum CCL11, HGF, and IL-6:IL-10 ratio were associated with poor outcomes (p = 0.038, 0.005, 0.02). Positive CSF and serum NfL correlation, and negative GCS and serum NfL correlation were observed. Median NfL levels were higher in children with abnormal admission GCS and poor outcomes. Measuring immune mediators and brain injury markers in AES provides valuable diagnostic insights, with the potential to facilitate rapid diagnosis and prognosis. The correlation between CSF and serum NfL, along with distinctive serum cytokine profiles across various etiologies, indicates the adequacy of blood samples alone for assessment and monitoring. The association of elevated levels of CCL11, HGF, and an increased IL-6:IL-10 ratio with adverse outcomes suggests promising avenues for therapeutic exploration, warranting further investigation.

Cognitive domains affected post-COVID-19; a systematic review and meta-analysis

BACKGROUND AND PURPOSE

This review aims to characterize the pattern of post-COVID-19 cognitive impairment, allowing better prediction of impact on daily function to inform clinical management and rehabilitation.

METHODS

A systematic review and meta-analysis of neurocognitive sequelae following COVID-19 was conducted, following PRISMA-S guidelines. Studies were included if they reported domain-specific cognitive assessment in patients with COVID-19 at >4 weeks post-infection. Studies were deemed high-quality if they had >40 participants, utilized healthy controls, had low attrition rates and mitigated for confounders.

RESULTS

Five of the seven primary Diagnostic and Statistical Manual of Mental Disorders (DSM-5) cognitive domains were assessed by enough high-quality studies to facilitate meta-analysis. Medium effect sizes indicating impairment in patients post-COVID-19 versus controls were seen across executive function (standardised mean difference (SMD) -0.45), learning and memory (SMD -0.55), complex attention (SMD -0.54) and language (SMD -0.54), with perceptual motor function appearing to be impacted to a greater degree (SMD -0.70). A narrative synthesis of the 56 low-quality studies also suggested no obvious pattern of impairment.

CONCLUSIONS

This review found moderate impairments across multiple domains of cognition in patients post-COVID-19, with no specific pattern. The reported literature was significantly heterogeneous, with a wide variety of cognitive tasks, small sample sizes and disparate initial disease severities limiting interpretability. The finding of consistent impairment across a range of cognitive tasks suggests broad, as opposed to domain-specific, brain dysfunction. Future studies should utilize a harmonized test battery to facilitate inter-study comparisons, whilst also accounting for the interactions between COVID-19, neurological sequelae and mental health, the interplay between which might explain cognitive impairment.

Mental health outcomes of encephalitis: An international web-based study

BACKGROUND AND PURPOSE

Acute encephalitis is associated with psychiatric symptoms. Despite this, the extent of mental health problems following encephalitis has not been systematically reported.

METHODS

We recruited adults who had been diagnosed with encephalitis of any aetiology to complete a web-based questionnaire.

RESULTS

In total, 445 respondents from 31 countries (55.1% UK, 23.1% USA) responded. Infectious encephalitis constituted 65.4% of cases, autoimmune 29.7%. Mean age was 50.1 years, 65.8% were female, and median time since encephalitis diagnosis was 7 years. The most common self-reported psychiatric symptoms were anxiety (75.2%), sleep problems (64.4%), mood problems (62.2%), and unexpected crying (35.2%). Self-reported psychiatric diagnoses were common: anxiety (44.0%), depression (38.6%), panic disorder (15.7%), and posttraumatic stress disorder (PTSD; 21.3%). Severe mental illnesses such as psychosis (3.3%) and bipolar affective disorder (3.1%) were reported. Self-reported diagnosis rates were broadly consistent with results from the Psychiatric Diagnostic Screening Questionnaire. Many respondents also reported they had symptoms of anxiety (37.5%), depression (28.1%), PTSD (26.8%), or panic disorder (20.9%) that had not been diagnosed. Rates of psychiatric symptoms did not differ between autoimmune and infectious encephalitis. In total, 37.5% respondents had thought about suicide, and 4.4% had attempted suicide, since their encephalitis diagnosis. More than half of respondents (53.5%) reported they had no, or substandard, access to appropriate mental health care. High rates of sensory hypersensitivities (>75%) suggest a previously unreported association.

CONCLUSIONS

This large international survey indicates that psychiatric symptoms following encephalitis are common and that mental health care provision may be inadequate. We highlight a need for proactive psychiatric input.

Para-infectious brain injury in COVID-19 persists at follow-up despite attenuated cytokine and autoantibody responses

To understand neurological complications of COVID-19 better both acutely and for recovery, we measured markers of brain injury, inflammatory mediators, and autoantibodies in 203 hospitalised participants; 111 with acute sera (1-11 days post-admission) and 92 convalescent sera (56 with COVID-19-associated neurological diagnoses). Here we show that compared to 60 uninfected controls, tTau, GFAP, NfL, and UCH-L1 are increased with COVID-19 infection at acute timepoints and NfL and GFAP are significantly higher in participants with neurological complications. Inflammatory mediators (IL-6, IL-12p40, HGF, M-CSF, CCL2, and IL-1RA) are associated with both altered consciousness and markers of brain injury. Autoantibodies are more common in COVID-19 than controls and some (including against MYL7, UCH-L1, and GRIN3B) are more frequent with altered consciousness. Additionally, convalescent participants with neurological complications show elevated GFAP and NfL, unrelated to attenuated systemic inflammatory mediators and to autoantibody responses. Overall, neurological complications of COVID-19 are associated with evidence of neuroglial injury in both acute and late disease and these correlate with dysregulated innate and adaptive immune responses acutely.

Pre-existing neurological conditions and COVID-19 co-infection: Data from systematic reviews, meta-analyses, and scoping reviews

BACKGROUND

Pre-existing neurological diseases have been identified as risk factors for severe COVID-19 infection and death. There is a lack of comprehensive literature review assessing the relationship between pre-existing neurological conditions and COVID-19 outcomes. Identification of high risk groups is critical for optimal treatment and care.

METHODS

A literature review was conducted for systematic reviews, meta-analyses, and scoping reviews published between January 1, 2020 and January 1, 2023. Literature assessing individuals with pre-existing neurological diseases and COVID-19 infection was included. Information regarding infection severity was extracted, and potential limitations were identified.

RESULTS

Thirty-nine articles met inclusion criteria, with data assessing >3 million patients from 51 countries. 26/51 (50.9%) of countries analyzed were classified as high income, while the remaining represented middle-low income countries (25/51; 49.0%). A majority of evidence focused on the impact of cerebrovascular disease (17/39; 43.5%) and dementia (5/39; 12.8%) on COVID-19 severity and mortality. 92.3% of the articles (36/39) suggested a significant association between neurological conditions and increased risk of severe COVID-19 and mortality. Cerebrovascular disease, dementia, Parkinson's disease, and epilepsy were associated with increased COVID severity and mortality.

CONCLUSION

Pre-existing neurological diseases including cerebrovascular disease, Alzheimer's disease and other dementias, epilepsy, and Parkinson's disease are significant risk factors for severity of COVID-19 infection and mortality in the acute infectious period. Given that 61.5% (24/39) of the current evidence only includes data from 2020, further updated literature is crucial to identify the relationship between chronic neurological conditions and clinical characteristics of COVID-19 variants.

Global Landscape of Encephalitis: Key Priorities to Reduce Future Disease Burden

Encephalitis affects people across the lifespan, has high rates of mortality and morbidity, and results in significant neurological sequelae with long-term consequences to quality of life and wider society. The true incidence is currently unknown due to inaccurate reporting systems. The disease burden of encephalitis is unequally distributed across the globe being highest in low- and middle-income countries where resources are limited. Here countries often lack diagnostic testing, with poor access to essential treatments and neurological services, and limited surveillance and vaccination programs. Many types of encephalitis are vaccine preventable, whereas others are treatable with early diagnosis and appropriate management. In this viewpoint, we provide a narrative review of key aspects of diagnosis, surveillance, treatment, and prevention of encephalitis and highlight priorities for public health, clinical management, and research, to reduce the disease burden.

Clinical predictors of encephalitis in UK adults-A multi-centre prospective observational cohort study

OBJECTIVES

Encephalitis, brain inflammation and swelling, most often caused by an infection or the body's immune defences, can have devastating consequences, especially if diagnosed late. We looked for clinical predictors of different types of encephalitis to help clinicians consider earlier treatment.

METHODS

We conducted a multicentre prospective observational cohort study (ENCEPH-UK) of adults (> 16 years) with suspected encephalitis at 31 UK hospitals. We evaluated clinical features and investigated for infectious and autoimmune causes.

RESULTS

341 patients were enrolled between December 2012 and December 2015 and followed up for 12 months. 233 had encephalitis, of whom 65 (28%) had HSV, 38 (16%) had confirmed or probable autoimmune encephalitis, and 87 (37%) had no cause found. The median time from admission to 1st dose of aciclovir for those with HSV was 14 hours (IQR 5-50); time to 1st dose of immunosuppressant for the autoimmune group was 125 hours (IQR 45-250). Compared to non-HSV encephalitis, patients with HSV more often had fever, lower serum sodium and lacked a rash. Those with probable or confirmed autoimmune encephalitis were more likely to be female, have abnormal movements, normal serum sodium levels and a cerebrospinal fluid white cell count < 20 cells x106/L, but they were less likely to have a febrile illness.

CONCLUSIONS

Initiation of treatment for autoimmune encephalitis is delayed considerably compared with HSV encephalitis. Clinical features can help identify patients with autoimmune disease and could be used to initiate earlier presumptive therapy.

Encephalitis: diagnosis, management and recent advances in the field of encephalitides

Encephalitis describes inflammation of the brain parenchyma, typically caused by either an infectious agent or through an autoimmune process which may be postinfectious, paraneoplastic or idiopathic. Patients can present with a combination of fever, alterations in behaviour, personality, cognition and consciousness. They may also exhibit focal neurological deficits, seizures, movement disorders and/or autonomic instability. However, it can sometimes present non-specifically, and this combined with its many causes make it a difficult to manage neurological syndrome. Despite improved treatments in some forms of encephalitides, encephalitis remains a global concern due to its high mortality and morbidity. Prompt diagnosis and administration of specific and supportive management options can lead to better outcomes. Over the last decade, research in encephalitis has led to marked developments in the understanding, diagnosis and management of encephalitis. In parallel, the number of autoimmune encephalitis syndromes has rapidly expanded and clinically characteristic syndromes in association with pathogenic autoantibodies have been defined. By focusing on findings presented at the Encephalitis Society's conference in December 2021, this article reviews the causes, clinical manifestations and management of encephalitis and integrate recent advances and challenges of research into encephalitis.

Global uncertainty in the diagnosis of neurological complications of SARS-CoV-2 infection by both neurologists and non-neurologists: An international inter-observer variability study

INTRODUCTION

Uniform case definitions are required to ensure harmonised reporting of neurological syndromes associated with SARS-CoV-2. Moreover, it is unclear how clinicians perceive the relative importance of SARS-CoV-2 in neurological syndromes, which risks under- or over-reporting.

METHODS

We invited clinicians through global networks, including the World Federation of Neurology, to assess ten anonymised vignettes of SARS-CoV-2 neurological syndromes. Using standardised case definitions, clinicians assigned a diagnosis and ranked association with SARS-CoV-2. We compared diagnostic accuracy and assigned association ranks between different settings and specialties and calculated inter-rater agreement for case definitions as "poor" (κ ≤ 0.4), "moderate" or "good" (κ > 0.6).

RESULTS

1265 diagnoses were assigned by 146 participants from 45 countries on six continents. The highest correct proportion were cerebral venous sinus thrombosis (CVST, 95.8%), Guillain-Barré syndrome (GBS, 92.4%) and headache (91.6%) and the lowest encephalitis (72.8%), psychosis (53.8%) and encephalopathy (43.2%). Diagnostic accuracy was similar between neurologists and non-neurologists (median score 8 vs. 7/10, p = 0.1). Good inter-rater agreement was observed for five diagnoses: cranial neuropathy, headache, myelitis, CVST, and GBS and poor agreement for encephalopathy. In 13% of vignettes, clinicians incorrectly assigned lowest association ranks, regardless of setting and specialty.

CONCLUSION

The case definitions can help with reporting of neurological complications of SARS-CoV-2, also in settings with few neurologists. However, encephalopathy, encephalitis, and psychosis were often misdiagnosed, and clinicians underestimated the association with SARS-CoV-2. Future work should refine the case definitions and provide training if global reporting of neurological syndromes associated with SARS-CoV-2 is to be robust.

Addressing vaccine-preventable encephalitis in vulnerable populations

PURPOSE OF REVIEW

Vaccinations have been pivotal in lowering the global disease burden of vaccine-preventable encephalitides, including Japanese encephalitis, tick-borne encephalitis, measles encephalitis, and rabies encephalitis, among others.

RECENT FINDINGS

Populations vulnerable to vaccine-preventable infections that may lead to encephalitis include those living in endemic and rural areas, military members, migrants, refugees, international travelers, younger and older persons, pregnant women, the immunocompromised, outdoor, healthcare and laboratory workers, and the homeless. There is scope for improving the availability and distribution of vaccinations, vaccine equity, surveillance of vaccine-preventable encephalitides, and public education and information.

SUMMARY

Addressing these gaps in vaccination strategies will allow for improved vaccination coverage and lead to better health outcomes for those most at risk for vaccine-preventable encephalitis.

Encephalitis: diagnosis, management and recent advances in the field of encephalitides

Encephalitis describes inflammation of the brain parenchyma, typically caused by either an infectious agent or through an autoimmune process which may be postinfectious, paraneoplastic or idiopathic. Patients can present with a combination of fever, alterations in behaviour, personality, cognition and consciousness. They may also exhibit focal neurological deficits, seizures, movement disorders and/or autonomic instability. However, it can sometimes present non-specifically, and this combined with its many causes make it a difficult to manage neurological syndrome. Despite improved treatments in some forms of encephalitides, encephalitis remains a global concern due to its high mortality and morbidity. Prompt diagnosis and administration of specific and supportive management options can lead to better outcomes. Over the last decade, research in encephalitis has led to marked developments in the understanding, diagnosis and management of encephalitis. In parallel, the number of autoimmune encephalitis syndromes has rapidly expanded and clinically characteristic syndromes in association with pathogenic autoantibodies have been defined. By focusing on findings presented at the Encephalitis Society's conference in December 2021, this article reviews the causes, clinical manifestations and management of encephalitis and integrate recent advances and challenges of research into encephalitis.

Consensus Clinical Guidance for Diagnosis and Management of Adult COVID-19 Encephalopathy Patients

Encephalopathy, a common condition among patients hospitalized with COVID-19, can be a challenge to manage and negatively affect prognosis. While encephalopathy may present clinically as delirium, subsyndromal delirium, or coma and may be a result of systemic causes such as hypoxia, COVID-19 has also been associated with more prolonged encephalopathy due to less common but nevertheless severe complications, such as inflammation of the brain parenchyma (with or without cerebrovascular involvement), demyelination, or seizures, which may be disproportionate to COVID-19 severity and require specific management. Given the large number of patients hospitalized with severe acute respiratory syndrome coronavirus-2 infection, even these relatively unlikely complications are increasingly recognized and are particularly important because they require specific management. Therefore, the aim of this review is to provide pragmatic guidance on the management of COVID-19 encephalopathy through consensus agreement of the Global COVID-19 Neuro Research Coalition. A systematic literature search of MEDLINE, medRxiv, and bioRxiv was conducted between January 1, 2020, and June 21, 2021, with additional review of references cited within the identified bibliographies. A modified Delphi approach was then undertaken to develop recommendations, along with a parallel approach to score the strength of both the recommendations and the supporting evidence. This review presents analysis of contemporaneous evidence for the definition, epidemiology, and pathophysiology of COVID-19 encephalopathy and practical guidance for clinical assessment, investigation, and both acute and long-term management.

Fewer COVID-19 Neurological Complications with Dexamethasone and Remdesivir

OBJECTIVE

The objective of this study was to assess the impact of treatment with dexamethasone, remdesivir or both on neurological complications in acute coronavirus diease 2019 (COVID-19).

METHODS

We used observational data from the International Severe Acute and emerging Respiratory Infection Consortium World Health Organization (WHO) Clinical Characterization Protocol, United Kingdom. Hospital inpatients aged ≥18 years with laboratory-confirmed severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection admitted between January 31, 2020, and June 29, 2021, were included. Treatment allocation was non-blinded and performed by reporting clinicians. A propensity scoring methodology was used to minimize confounding. Treatment with remdesivir, dexamethasone, or both was assessed against the standard of care. The primary outcome was a neurological complication occurring at the point of death, discharge, or resolution of the COVID-19 clinical episode.

RESULTS

Out of 89,297 hospital inpatients, 64,088 had severe COVID-19 and 25,209 had non-hypoxic COVID-19. Neurological complications developed in 4.8% and 4.5%, respectively. In both groups, neurological complications were associated with increased mortality, intensive care unit (ICU) admission, worse self-care on discharge, and time to recovery. In patients with severe COVID-19, treatment with dexamethasone (n = 21,129), remdesivir (n = 1,428), and both combined (n = 10,846) were associated with a lower frequency of neurological complications: OR = 0.76 (95% confidence interval [CI] = 0.69-0.83), OR = 0.69 (95% CI = 0.51-0.90), and OR = 0.54 (95% CI = 0.47-0.61), respectively. In patients with non-hypoxic COVID-19, dexamethasone (n = 2,580) was associated with less neurological complications (OR = 0.78, 95% CI = 0.62-0.97), whereas the dexamethasone/remdesivir combination (n = 460) showed a similar trend (OR = 0.63, 95% CI = 0.31-1.15).

INTERPRETATION

Treatment with dexamethasone, remdesivir, or both in patients hospitalized with COVID-19 was associated with a lower frequency of neurological complications in an additive manner, such that the greatest benefit was observed in patients who received both drugs together. ANN NEUROL 2023;93:88-102.

Brain injury in COVID-19 is associated with dysregulated innate and adaptive immune responses

COVID-19 is associated with neurological complications including stroke, delirium and encephalitis. Furthermore, a post-viral syndrome dominated by neuropsychiatric symptoms is common, and is seemingly unrelated to COVID-19 severity. The true frequency and underlying mechanisms of neurological injury are unknown, but exaggerated host inflammatory responses appear to be a key driver of COVID-19 severity. We investigated the dynamics of, and relationship between, serum markers of brain injury [neurofilament light (NfL), glial fibrillary acidic protein (GFAP) and total tau] and markers of dysregulated host response (autoantibody production and cytokine profiles) in 175 patients admitted with COVID-19 and 45 patients with influenza. During hospitalization, sera from patients with COVID-19 demonstrated elevations of NfL and GFAP in a severity-dependent manner, with evidence of ongoing active brain injury at follow-up 4 months later. These biomarkers were associated with elevations of pro-inflammatory cytokines and the presence of autoantibodies to a large number of different antigens. Autoantibodies were commonly seen against lung surfactant proteins but also brain proteins such as myelin associated glycoprotein. Commensurate findings were seen in the influenza cohort. A distinct process characterized by elevation of serum total tau was seen in patients at follow-up, which appeared to be independent of initial disease severity and was not associated with dysregulated immune responses unlike NfL and GFAP. These results demonstrate that brain injury is a common consequence of both COVID-19 and influenza, and is therefore likely to be a feature of severe viral infection more broadly. The brain injury occurs in the context of dysregulation of both innate and adaptive immune responses, with no single pathogenic mechanism clearly responsible.

Increased volume of cerebral oedema is associated with risk of acute seizure activity and adverse neurological outcomes in encephalitis - regional and volumetric analysis in a multi-centre cohort

BACKGROUND

Seizures can occur unpredictably in patients with acute encephalitis syndrome (AES), and many suffer from poor long-term neurological sequelae. Establishing factors associated with acute seizures risk and poor outcomes could support clinical care. We aimed to conduct regional and volumetric analysis of cerebral oedema on magnetic resonance imaging (MRI) in patients with AES. We assessed the relationship of brain oedema with acute seizure activity and long-term neurological outcome.

METHODS

In a multi-centre cohort study, adults and children presenting with an AES were recruited in the UK. The clinical and brain MRI data were retrospectively reviewed. The outcomes variables were inpatient acute seizure activity and neurological disability at six-months post-discharge. A poor outcome was defined as a Glasgow outcome score (GOS) of 1-3. We quantified regional brain oedema on MRI through stereological examination of T2-weighted images using established methodology by independent and blinded assessors. Clinical and neuroimaging variables were analysed by multivariate logistic regression to assess for correlation with acute seizure activity and outcome.

RESULTS

The study cohort comprised 69 patients (mean age 31.8 years; 53.6% female), of whom 41 (59.4%) had acute seizures as inpatients. A higher Glasgow coma scale (GCS) score on admission was a negative predictor of seizures (OR 0.61 [0.46-0.83], p = 0.001). Even correcting for GCS on admission, the presence of cortical oedema was a significant risk factor for acute seizure activity (OR 5.48 [1.62-18.51], p = 0.006) and greater volume of cerebral oedema in these cortical structures increased the risk of acute seizures (OR 1.90 [1.12-3.21], p = 0.017). At six-month post-discharge, 21 (30.4%) had a poor neurological outcome. Herpes simplex virus encephalitis was associated with higher risk of poor outcomes in univariate analysis (OR 3.92 [1.08-14.20], p = 0.038). When controlling for aetiology, increased volume of cerebral oedema was an independent risk factor for adverse neurological outcome at 6 months (OR 1.73 [1.06-2.83], p = 0.027).

CONCLUSIONS

Both the presence and degree of cerebral oedema on MRIs of patients with AES may help identify patients at risk of acute seizure activity and subsequent long-term morbidity.

Neurological manifestations of scrub typhus infection: A systematic review and meta-analysis of clinical features and case fatality

BACKGROUND

Scrub typhus has become a leading cause of central nervous system (CNS) infection in endemic regions. As a treatable condition, prompt recognition is vital. However, few studies have focused on describing the symptomology and outcomes of neurological scrub typhus infection. We conducted a systematic review and meta-analysis to report the clinical features and case fatality ratio (CFR) in patients with CNS scrub typhus infection.

METHODS

A search and analysis plan was published in PROSPERO [ID 328732]. A systematic search of PubMed and Scopus was performed and studies describing patients with CNS manifestations of proven scrub typhus infection were included. The outcomes studied were weighted pooled prevalence (WPP) of clinical features during illness and weighted CFR.

RESULTS

Nineteen studies with 1,221 (656 adults and 565 paediatric) patients were included. The most common clinical features in CNS scrub typhus were those consistent with non-specific acute encephalitis syndromes (AES), such as fever (WPP 100.0% [99.5%-100.0%, I2 = 47.8%]), altered sensorium (67.4% [54.9-78.8%, I2 = 93.3%]), headache (65.0% [51.5-77.6%, I2 = 95.1%]) and neck stiffness 56.6% (29.4-80.4%, I2 = 96.3%). Classical features of scrub typhus were infrequently identified; an eschar was found in only 20.8% (9.8%-34.3%, I2 = 95.4%) and lymphadenopathy in 24.1% (95% CI 11.8% - 38.9%, I2 = 87.8%). The pooled CFR (95% CI) was 3.6% (1.5%- 6.4%, I2 = 67.3%). Paediatric cohorts had a CFR of 6.1% (1.9-12.1%, I2 = 77%) whilst adult cohorts reported 2.6% (0.7-5.3%, I2 = 43%).

CONCLUSION

Our meta-analyses illustrate that 3.6% of patients with CNS manifestations of scrub typhus die. Clinicians should have a high index of suspicion for scrub typhus in patients presenting with AES in endemic regions and consider starting empiric treatment whilst awaiting results of investigations, even in the absence of classical signs such as an eschar or lymphadenopathy.

Neurological and psychiatric presentations associated with human monkeypox virus infection: A systematic review and meta-analysis

Background

Neuropsychiatric presentations of monkeypox (MPX) infection have not been well characterised, despite evidence of nervous system involvement associated with the related smallpox infection.

Methods

In this pre-registered (PROSPERO ID 336649) systematic review and meta-analysis, we searched MEDLINE, EMBASE, PsycINFO, AMED and the preprint server MedRxiv up to 31/05/2022. Any study design of humans infected with MPX that reported a neurological or psychiatric presentation was included. For eligible symptoms, we calculated a pooled prevalence using an inverse variance approach and corresponding 95% confidence intervals. The degree of variability that could be explained by between-study heterogeneity was assessed using the I 2 statistic. Risk of bias was assessed with the Newcastle Ottawa Scale and the Joanna Briggs Institute quality assessment tool.

Findings

From 1705 unique studies, we extracted data on 19 eligible studies (1512 participants, 1031 with confirmed infection using CDC criteria or PCR testing) most of which were cohort studies and case series with no control groups. Study quality was generally moderate. Three clinical features were eligible for meta-analysis: seizure 2.7% (95% CI 0.7-10.2%, I2 0%), confusion 2.4% (95% CI 1.1-5.2%, I2 0%) and encephalitis 2.0% (95% 0.5-8.2%, I2 55.8%). Other frequently reported symptoms included myalgia, headache and fatigue, where heterogeneity was too high for estimation of pooled prevalences, possibly as a result of differences in viral clades and study methodology.

Interpretation

There is preliminary evidence for a range of neuropsychiatric presentations including severe neurological complications (encephalitis and seizure) and nonspecific neurological features (confusion, headache and myalgia). There is less evidence regarding the psychiatric presentations or sequelae of MPX. This may warrant surveillance within the current MPX outbreak, with prospective longitudinal studies evaluating the mid- to long-term sequelae of the virus. Robust methods to evaluate the potential causality of MPX with these clinical features are required. More evidence is necessary to explain heterogeneity in prevalence estimates.

Funding

UKRI/MRC (MR/V03605X/1), MRC-CSF (MR/V007181/1), MRC/AMED (MR/T028750/1) and the Wellcome Trust (102186/B/13/Z) and (102186/B/13/Z) and UCLH BRC.

Reliability of multi-site UK Biobank MRI brain phenotypes for the assessment of neuropsychiatric complications of SARS-CoV-2 infection: The COVID-CNS travelling heads study

INTRODUCTION

Magnetic resonance imaging (MRI) of the brain could be a key diagnostic and research tool for understanding the neuropsychiatric complications of COVID-19. For maximum impact, multi-modal MRI protocols will be needed to measure the effects of SARS-CoV-2 infection on the brain by diverse potentially pathogenic mechanisms, and with high reliability across multiple sites and scanner manufacturers. Here we describe the development of such a protocol, based upon the UK Biobank, and its validation with a travelling heads study. A multi-modal brain MRI protocol comprising sequences for T1-weighted MRI, T2-FLAIR, diffusion MRI (dMRI), resting-state functional MRI (fMRI), susceptibility-weighted imaging (swMRI), and arterial spin labelling (ASL), was defined in close approximation to prior UK Biobank (UKB) and C-MORE protocols for Siemens 3T systems. We iteratively defined a comparable set of sequences for General Electric (GE) 3T systems. To assess multi-site feasibility and between-site variability of this protocol, N = 8 healthy participants were each scanned at 4 UK sites: 3 using Siemens PRISMA scanners (Cambridge, Liverpool, Oxford) and 1 using a GE scanner (King's College London). Over 2,000 Imaging Derived Phenotypes (IDPs), measuring both data quality and regional image properties of interest, were automatically estimated by customised UKB image processing pipelines (S2 File). Components of variance and intra-class correlations (ICCs) were estimated for each IDP by linear mixed effects models and benchmarked by comparison to repeated measurements of the same IDPs from UKB participants. Intra-class correlations for many IDPs indicated good-to-excellent between-site reliability. Considering only data from the Siemens sites, between-site reliability generally matched the high levels of test-retest reliability of the same IDPs estimated in repeated, within-site, within-subject scans from UK Biobank. Inclusion of the GE site resulted in good-to-excellent reliability for many IDPs, although there were significant between-site differences in mean and scaling, and reduced ICCs, for some classes of IDP, especially T1 contrast and some dMRI-derived measures. We also identified high reliability of quantitative susceptibility mapping (QSM) IDPs derived from swMRI images, multi-network ICA-based IDPs from resting-state fMRI, and olfactory bulb structure IDPs from T1, T2-FLAIR and dMRI data.

CONCLUSION

These results give confidence that large, multi-site MRI datasets can be collected reliably at different sites across the diverse range of MRI modalities and IDPs that could be mechanistically informative in COVID brain research. We discuss limitations of the study and strategies for further harmonisation of data collected from sites using scanners supplied by different manufacturers. These acquisition and analysis protocols are now in use for MRI assessments of post-COVID patients (N = 700) as part of the ongoing COVID-CNS study.

Acute seizure risk in patients with encephalitis: development and validation of clinical prediction models from two independent prospective multicentre cohorts

Objective

In patients with encephalitis, the development of acute symptomatic seizures is highly variable, but when present is associated with a worse outcome. We aimed to determine the factors associated with seizures in encephalitis and develop a clinical prediction model.

Methods

We analysed 203 patients from 24 English hospitals (2005-2008) (Cohort 1). Outcome measures were seizures prior to and during admission, inpatient seizures and status epilepticus. A binary logistic regression risk model was converted to a clinical score and independently validated on an additional 233 patients from 31 UK hospitals (2013-2016) (Cohort 2).

Results

In Cohort 1, 121 (60%) patients had a seizure including 103 (51%) with inpatient seizures. Admission Glasgow Coma Scale (GCS) ≤8/15 was predictive of subsequent inpatient seizures (OR (95% CI) 5.55 (2.10 to 14.64), p<0.001), including in those without a history of prior seizures at presentation (OR 6.57 (95% CI 1.37 to 31.5), p=0.025).A clinical model of overall seizure risk identified admission GCS along with aetiology (autoantibody-associated OR 11.99 (95% CI 2.09 to 68.86) and Herpes simplex virus 3.58 (95% CI 1.06 to 12.12)) (area under receiver operating characteristics curve (AUROC) =0.75 (95% CI 0.701 to 0.848), p<0.001). The same model was externally validated in Cohort 2 (AUROC=0.744 (95% CI 0.677 to 0.811), p<0.001). A clinical scoring system for stratifying inpatient seizure risk by decile demonstrated good discrimination using variables available on admission; age, GCS and fever (AUROC=0.716 (95% CI 0.634 to 0.798), p<0.001) and once probable aetiology established (AUROC=0.761 (95% CI 0.6840.839), p<0.001).

Conclusion

Age, GCS, fever and aetiology can effectively stratify acute seizure risk in patients with encephalitis. These findings can support the development of targeted interventions and aid clinical trial design for antiseizure medication prophylaxis.

Guillain-Barré syndrome following SARS-CoV-2 vaccination in the UK: a prospective surveillance study

Objective

To investigate features of Guillain-Barré syndrome (GBS) following SARS-CoV-2 vaccines and evaluate for a causal link between the two.

Methods

We captured cases of GBS after SARS-CoV-2 vaccination through a national, open-access, online surveillance system. For each case, the certainty of GBS was graded using the Brighton criteria, and the relationship to the vaccine was examined using modified WHO Causality Assessment criteria. We compared age distribution of cases with that of prepandemic GBS cases and clinical features with the International GBS Outcome Study (IGOS).

Results

Between 1 January and 30 June 2021, we received 67 reports of GBS following the ChAdOx1 vaccine (65 first doses) and three reports following the BNT162b2 vaccine (all first doses). The causal association with the vaccine was classified as probable for 56 (80%, all ChAdOx1), possible for 12 (17%, 10 ChAdOx1) and unlikely for two (3%, 1 ChAdOx1). A greater proportion of cases occurred in the 50–59 age group in comparison with prepandemic GBS. Most common clinical variants were sensorimotor GBS (n=55; 79%) and facial diplegia with paraesthesias (n=10; 14%). 10% (n=7/69) of patients reported an antecedent infection, compared with 77% (n=502/652) of the IGOS cohort (p<0.00001). Facial weakness (63% (n=44/70) vs 36% (n=220/620); p<0.00001) and sensory dysfunction (93% (n=63/68) vs 69% (n=408/588); p=0.00005) were more common but disease severity and outcomes were similar to the IGOS study.

Interpretation

Most reports of GBS followed the first dose of ChAdOx1 vaccine. While our study cannot confirm or refute causation, this observation, together with the absence of alternative aetiologies, different than expected age distribution and the presence of unusual clinical features support a causal link. Clinicians and surveillance bodies should remain vigilant to the possibility of this very rare adverse event and its atypical variants.

Prognostic indicators and outcomes of hospitalised COVID-19 patients with neurological disease: An individual patient data meta-analysis

Background

Neurological COVID-19 disease has been reported widely, but published studies often lack information on neurological outcomes and prognostic risk factors. We aimed to describe the spectrum of neurological disease in hospitalised COVID-19 patients; characterise clinical outcomes; and investigate factors associated with a poor outcome.

Methods

We conducted an individual patient data (IPD) meta-analysis of hospitalised patients with neurological COVID-19 disease, using standard case definitions. We invited authors of studies from the first pandemic wave, plus clinicians in the Global COVID-Neuro Network with unpublished data, to contribute. We analysed features associated with poor outcome (moderate to severe disability or death, 3 to 6 on the modified Rankin Scale) using multivariable models.

Results

We included 83 studies (31 unpublished) providing IPD for 1979 patients with COVID-19 and acute new-onset neurological disease. Encephalopathy (978 [49%] patients) and cerebrovascular events (506 [26%]) were the most common diagnoses. Respiratory and systemic symptoms preceded neurological features in 93% of patients; one third developed neurological disease after hospital admission. A poor outcome was more common in patients with cerebrovascular events (76% [95% CI 67–82]), than encephalopathy (54% [42–65]). Intensive care use was high (38% [35–41]) overall, and also greater in the cerebrovascular patients. In the cerebrovascular, but not encephalopathic patients, risk factors for poor outcome included breathlessness on admission and elevated D-dimer. Overall, 30-day mortality was 30% [27–32]. The hazard of death was comparatively lower for patients in the WHO European region.

Interpretation

Neurological COVID-19 disease poses a considerable burden in terms of disease outcomes and use of hospital resources from prolonged intensive care and inpatient admission; preliminary data suggest these may differ according to WHO regions and country income levels. The different risk factors for encephalopathy and stroke suggest different disease mechanisms which may be amenable to intervention, especially in those who develop neurological symptoms after hospital admission.

Neuroimmune disorders in COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the aetiologic agent of the coronavirus disease 2019 (COVID-19), is now rapidly disseminating throughout the world with 147,443,848 cases reported so far. Around 30-80% of cases (depending on COVID-19 severity) are reported to have neurological manifestations including anosmia, stroke, and encephalopathy. In addition, some patients have recognised autoimmune neurological disorders, including both central (limbic and brainstem encephalitis, acute disseminated encephalomyelitis [ADEM], and myelitis) and peripheral diseases (Guillain-Barré and Miller Fisher syndrome). We systematically describe data from 133 reported series on the Neurology and Neuropsychiatry of COVID-19 blog ( https://blogs.bmj.com/jnnp/2020/05/01/the-neurology-and-neuropsychiatry-of-covid-19/ ) providing a comprehensive overview concerning the diagnosis, and treatment of patients with neurological immune-mediated complications of SARS-CoV-2. In most cases the latency to neurological disorder was highly variable and the immunological or other mechanisms involved were unclear. Despite specific neuronal or ganglioside antibodies only being identified in 10, many had apparent responses to immunotherapies. Although the proportion of patients experiencing immune-mediated neurological disorders is small, the total number is likely to be underestimated. The early recognition and improvement seen with use of immunomodulatory treatment, even in those without identified autoantibodies, makes delayed or missed diagnoses risk the potential for long-term disability, including the emerging challenge of post-acute COVID-19 sequelae (PACS). Finally, potential issues regarding the use of immunotherapies in patients with pre-existent neuro-immunological disorders are also discussed.

Immune-Mediated Mechanisms of COVID-19 Neuropathology

Although SARS-CoV-2 causes a respiratory viral infection, there is a large incidence of neurological complications occurring in COVID-19 patients. These range from headaches and loss of smell to encephalitis and strokes. Little is known about the likely diverse mechanisms causing these pathologies and there is a dire need to understand how to prevent and treat them. This review explores recent research from the perspective of investigating how the immune system could play a role in neurological complications, including cytokines, blood biomarkers, immune cells, and autoantibodies. We also discuss lessons learnt from animal models. Overall, we highlight two key points that have emerged from increasing evidence: (1) SARS-CoV-2 does not invade the brain in the majority of cases and so the associated neurological complications might arise from indirect effects, such as immune activation (2) although the immune system plays a critical role in controlling the virus, its dysregulation can cause pathology.

Neuroinvasion and Neurotropism by SARS-CoV-2 Variants in the K18-hACE2 Mouse

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) not only affects the respiratory tract but also causes neurological symptoms such as loss of smell and taste, headache, fatigue or severe cerebrovascular complications. Using transgenic mice expressing human angiotensin-converting enzyme 2 (hACE2), we investigated the spatiotemporal distribution and pathomorphological features in the CNS following intranasal infection with SARS-CoV-2 variants, as well as after prior influenza A virus infection. Apart from Omicron, we found all variants to frequently spread to and within the CNS. Infection was restricted to neurons and appeared to spread from the olfactory bulb mainly in basally oriented regions in the brain and into the spinal cord, independent of ACE2 expression and without evidence of neuronal cell death, axonal damage or demyelination. However, microglial activation, microgliosis and a mild macrophage and T cell dominated inflammatory response was consistently observed, accompanied by apoptotic death of endothelial, microglial and immune cells, without their apparent infection. Microgliosis and immune cell apoptosis indicate a potential role of microglia for pathogenesis and viral effect in COVID-19 and the possible impairment of neurological functions, especially in long COVID. These data may also be informative for the selection of therapeutic candidates and broadly support the investigation of agents with adequate penetration into relevant regions of the CNS.

How should we define a 'good' outcome from encephalitis? A systematic review of the range of outcome measures used in the long-term follow-up of patients with encephalitis

INTRODUCTION

Encephalitis is typically caused by infection or autoimmunity. Most survivors suffer complex neurological and psychiatric sequelae. Standardised outcome measures are needed for accurate interpretation of observational studies and clinical trials. Step one in this process is understanding the strengths and weaknesses of those in use.

METHODS

We performed a systematic literature review searching six databases. One reviewer screened titles and abstracts, and two reviewers determined if shortlisted full-text articles met inclusion criteria. Key data were extracted from these papers and presented as a narrative summary.

RESULTS

Thirty-seven outcome measures were used for 3,133 patients across the 35 included papers, of which, only one was developed for encephalitis. The outcome measures used in most patients were the Glasgow Outcome Score used in 1,436 (46%), Barthel Index used in 1,173 (37%), Euro-QoL-5D used in 1,107 (35%) and modified Rankin Scale used in 1,034 (33%).

CONCLUSION

Most of the 37 measures assessed a single category of sequelae using 5-8-point scales and were not validated for use in encephalitis. Research is needed to develop a composite outcome measure for use in clinical practice and a core-outcomes set for use in clinical trials. For now, the Liverpool Outcome Score offers a good choice for clinicians.

Viral capture sequencing detects unexpected viruses in the cerebrospinal fluid of adults with meningitis

OBJECTIVES

Many patients with meningitis have no aetiology identified leading to unnecessary antimicrobials and prolonged hospitalisation. We used viral capture sequencing to identify possible pathogenic viruses in adults with community-acquired meningitis.

METHODS

Cerebrospinal fluid (CSF) from 73 patients was tested by VirCapSeq-VERT, a probe set designed to capture viral targets using high throughput sequencing. Patients were categorised as suspected viral meningitis - CSF pleocytosis, no pathogen identified (n = 38), proven viral meningitis - CSF pleocytosis with a pathogen identified (n = 15) or not meningitis - no CSF pleocytosis (n = 20).

RESULTS

VirCapSeq-VERT detected virus in the CSF of 16/38 (42%) of those with suspected viral meningitis, including twelve individual viruses. A potentially clinically relevant virus was detected in 9/16 (56%). Unexpectedly Toscana virus, rotavirus and Saffold virus were detected and assessed to be potential causative agents.

CONCLUSION

VirCapSeq-VERT increases the probability of detecting a virus. Using this agnostic approach we identified Toscana virus and, for the first time in adults, rotavirus and Saffold virus, as potential causative agents in adult meningitis. Further work is needed to determine the prevalence of atypical viral candidates as well as the clinical impact of using sequencing methods in real time. This knowledge can help to reduce antimicrobial use and hospitalisations leading to both patient and health system benefits.

Persistent neuropsychiatric symptoms after COVID-19: a systematic review and meta-analysis

The nature and extent of persistent neuropsychiatric symptoms after COVID-19 are not established. To help inform mental health service planning in the pandemic recovery phase, we systematically determined the prevalence of neuropsychiatric symptoms in survivors of COVID-19. For this pre-registered systematic review and meta-analysis (PROSPERO ID CRD42021239750), we searched MEDLINE, EMBASE, CINAHL and PsycINFO to 20 February 2021, plus our own curated database. We included peer-reviewed studies reporting neuropsychiatric symptoms at post-acute or later time-points after COVID-19 infection and in control groups where available. For each study, a minimum of two authors extracted summary data. For each symptom, we calculated a pooled prevalence using generalized linear mixed models. Heterogeneity was measured with I 2. Subgroup analyses were conducted for COVID-19 hospitalization, severity and duration of follow-up. From 2844 unique titles, we included 51 studies (n = 18 917 patients). The mean duration of follow-up after COVID-19 was 77 days (range 14-182 days). Study quality was most commonly moderate. The most prevalent neuropsychiatric symptom was sleep disturbance [pooled prevalence = 27.4% (95% confidence interval 21.4-34.4%)], followed by fatigue [24.4% (17.5-32.9%)], objective cognitive impairment [20.2% (10.3-35.7%)], anxiety [19.1% (13.3-26.8%)] and post-traumatic stress [15.7% (9.9-24.1%)]. Only two studies reported symptoms in control groups, both reporting higher frequencies in COVID-19 survivors versus controls. Between-study heterogeneity was high (I 2 = 79.6-98.6%). There was little or no evidence of differential symptom prevalence based on hospitalization status, severity or follow-up duration. Neuropsychiatric symptoms are common and persistent after recovery from COVID-19. The literature on longer-term consequences is still maturing but indicates a particularly high prevalence of insomnia, fatigue, cognitive impairment and anxiety disorders in the first 6 months after infection.

Antiepileptic drugs for seizure control in people with neurocysticercosis

BACKGROUND

Neurocysticercosis is the most common parasitic infection of the brain. Epilepsy is the most common clinical presentation, though people may also present with headache, symptoms of raised intracranial pressure, hydrocephalus, and ocular symptoms depending upon the localisation of the parasitic cysts. Anthelmintic drugs, antiepileptic drugs (AEDs), and anti-oedema drugs, such as steroids, form the mainstay of treatment. This is an updated version of the Cochrane Review previously published in 2019.

OBJECTIVES

To assess the effects (benefits and harms) of AEDs for the primary and secondary prevention of seizures in people with neurocysticercosis. For the question of primary prevention, we examined whether AEDs reduce the likelihood of seizures in people who had neurocysticercosis but had not had a seizure. For the question of secondary prevention, we examined whether AEDs reduce the likelihood of further seizures in people who had had at least one seizure due to neurocysticercosis. As part of primary prevention studies, we also aimed to examine which AED was beneficial in people with neurocysticercosis in terms of duration, dose, and side-effect profile.

SEARCH METHODS

For the 2021 update of this review, we searched the Cochrane Register of Studies (CRS Web), MEDLINE, and LILACS to January 2021. CRS Web includes randomised or quasi-randomised, controlled trials from CENTRAL, the Specialised Registers of Cochrane Review Groups, including Epilepsy, PubMed, Embase, ClinicalTrials.gov, and the World Health Organisation International Clinical Trials Registry Platform. We also checked the reference lists of identified studies, and contacted experts and colleagues in the field to search for additional and ongoing studies.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials. Single-blind, double-blind, or unblinded studies were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

We followed standard methodological procedures expected by Cochrane. Two review authors independently selected trials for inclusion and extracted the relevant data. The primary outcomes of interest were: proportion of individuals experiencing seizures, and time to first seizure post randomisation. Secondary outcomes included: seizure freedom, number of withdrawals, side effects, number of people seizure free with short or long durations of treatment, quality of life, therapy costs, hospitalisations, and mortality. We used an intention-to-treat analysis for the primary analysis. We calculated odds ratio (OR) for dichotomous data (proportion of individuals who experienced seizures, were seizure free for a specific time period (12 or 24 months), withdrew from treatment, developed drug-related side effects or complications, were seizure-free with each treatment policy, mortality), and planned to use mean difference (MD) for continuous data, if any continuous data were identified (quality of life, cost of treatment). We intended to evaluate time to first seizure after randomisation by calculating hazard ratios (HRs). We assessed precision using 95% confidence intervals (CIs). We stratified the analysis by treatment comparison. We also considered the duration of drug usage, co-medications, and the length of follow-up.

MAIN RESULTS

We did not find any trials that investigated the role of AEDs in preventing seizures among people with neurocysticercosis, presenting with symptoms other than seizures. We did not find any trials that directly compared individual AEDs for primary prevention in people with neurocysticercosis. We included four trials that evaluated the efficacy of short-term versus longer-term AED treatment for people with solitary neurocysticercosis (identified on computed tomography (CT) scan) who presented with seizures. In total, 466 people were enrolled. These studies compared AED treatment durations of 6, 12, and 24 months. The risk of seizure recurrence with six months of treatment compared with 12 to 24 months of treatment was inconclusive (odds ratio (OR) 1.34, 95% confidence interval (CI) 0.73 to 2.47; three studies, 360 participants; low-certainty evidence). The risk of seizure recurrence with six to 12 months of treatment compared with 24 months of treatment was inconclusive (OR 1.36, 95% CI 0.72 to 2.57; three studies, 385 participants; very low-certainty evidence). Two studies compared seizure recurrence with CT findings, and suggested that persistent and calcified lesions had a higher recurrence risk, and suggest longer duration of treatment with AEDs. One study reported no side effects, while the rest did not comment on side effects of the drugs. None of the studies addressed the quality of life of the participants. These studies had methodological deficiencies, such as small sample sizes, and a possibility of bias due to lack of blinding, which affect the results of the review.

AUTHORS' CONCLUSIONS

Despite neurocysticercosis being the most common cause of epilepsy worldwide, there is currently no evidence available regarding the use of AEDs as seizure prophylaxis among people presenting with symptoms other than seizures. For those presenting with seizures, there is no reliable evidence regarding the duration of treatment required. Therefore, there is a need for large scale randomised controlled trials to address these questions.

Antiepileptic drugs for seizure control in people with neurocysticercosis

BACKGROUND

Neurocysticercosis is the most common parasitic infection of the brain. Epilepsy is the most common clinical presentation, though people may also present with headache, symptoms of raised intracranial pressure, hydrocephalus, and ocular symptoms depending upon the localisation of the parasitic cysts. Anthelmintic drugs, antiepileptic drugs (AEDs), and anti-oedema drugs, such as steroids, form the mainstay of treatment. This is an updated version of the Cochrane Review previously published in 2019.

OBJECTIVES

To assess the effects (benefits and harms) of AEDs for the primary and secondary prevention of seizures in people with neurocysticercosis. For the question of primary prevention, we examined whether AEDs reduce the likelihood of seizures in people who had neurocysticercosis but had not had a seizure. For the question of secondary prevention, we examined whether AEDs reduce the likelihood of further seizures in people who had had at least one seizure due to neurocysticercosis. As part of primary prevention studies, we also aimed to examine which AED was beneficial in people with neurocysticercosis in terms of duration, dose, and side-effect profile.

SEARCH METHODS

For the 2021 update of this review, we searched the Cochrane Register of Studies (CRS Web), MEDLINE, and LILACS to January 2021. CRS Web includes randomised or quasi-randomised, controlled trials from CENTRAL, the Specialised Registers of Cochrane Review Groups, including Epilepsy, PubMed, Embase, ClinicalTrials.gov, and the World Health Organisation International Clinical Trials Registry Platform. We also checked the reference lists of identified studies, and contacted experts and colleagues in the field to search for additional and ongoing studies.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials. Single-blind, double-blind, or unblinded studies were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

We followed standard methodological procedures expected by Cochrane. Two review authors independently selected trials for inclusion and extracted the relevant data. The primary outcomes of interest were: proportion of individuals experiencing seizures, and time to first seizure post randomisation. Secondary outcomes included: seizure freedom, number of withdrawals, side effects, number of people seizure free with short or long durations of treatment, quality of life, therapy costs, hospitalisations, and mortality. We used an intention-to-treat analysis for the primary analysis. We calculated odds ratio (OR) for dichotomous data (proportion of individuals who experienced seizures, were seizure free for a specific time period (12 or 24 months), withdrew from treatment, developed drug-related side effects or complications, were seizure-free with each treatment policy, mortality), and planned to use mean difference (MD) for continuous data, if any continuous data were identified (quality of life, cost of treatment). We intended to evaluate time to first seizure after randomisation by calculating hazard ratios (HRs). We assessed precision using 95% confidence intervals (CIs). We stratified the analysis by treatment comparison. We also considered the duration of drug usage, co-medications, and the length of follow-up.

MAIN RESULTS

We did not find any trials that investigated the role of AEDs in preventing seizures among people with neurocysticercosis, presenting with symptoms other than seizures. We did not find any trials that directly compared individual AEDs for primary prevention in people with neurocysticercosis. We included four trials that evaluated the efficacy of short-term versus longer-term AED treatment for people with solitary neurocysticercosis (identified on computed tomography (CT) scan) who presented with seizures. In total, 466 people were enrolled. These studies compared AED treatment durations of 6, 12, and 24 months. The risk of seizure recurrence with six months of treatment compared with 12 to 24 months of treatment was inconclusive (odds ratio (OR) 1.34, 95% confidence interval (CI) 0.73 to 2.47; three studies, 360 participants; low-certainty evidence). The risk of seizure recurrence with six to 12 months of treatment compared with 24 months of treatment was inconclusive (OR 1.36, 95% CI 0.72 to 2.57; three studies, 385 participants; very low-certainty evidence). Two studies compared seizure recurrence with CT findings, and suggested that persistent and calcified lesions had a higher recurrence risk, and suggest longer duration of treatment with AEDs. One study reported no side effects, while the rest did not comment on side effects of the drugs. None of the studies addressed the quality of life of the participants. These studies had methodological deficiencies, such as small sample sizes, and a possibility of bias due to lack of blinding, which affect the results of the review.

AUTHORS' CONCLUSIONS

Despite neurocysticercosis being the most common cause of epilepsy worldwide, there is currently no evidence available regarding the use of AEDs as seizure prophylaxis among people presenting with symptoms other than seizures. For those presenting with seizures, there is no reliable evidence regarding the duration of treatment required. Therefore, there is a need for large scale randomised controlled trials to address these questions.

Antiphospholipid antibodies and neurological manifestations in acute COVID-19: A single-centre cross-sectional study

BACKGROUND

A high prevalence of antiphospholipid antibodies has been reported in case series of patients with neurological manifestations and COVID-19; however, the pathogenicity of antiphospholipid antibodies in COVID-19 neurology remains unclear.

METHODS

This single-centre cross-sectional study included 106 adult patients: 30 hospitalised COVID-neurological cases, 47 non-neurological COVID-hospitalised controls, and 29 COVID-non-hospitalised controls, recruited between March and July 2020. We evaluated nine antiphospholipid antibodies: anticardiolipin antibodies [aCL] IgA, IgM, IgG; anti-beta-2 glycoprotein-1 [aβ2GPI] IgA, IgM, IgG; anti-phosphatidylserine/prothrombin [aPS/PT] IgM, IgG; and anti-domain I β2GPI (aD1β2GPI) IgG.

FINDINGS

There was a high prevalence of antiphospholipid antibodies in the COVID-neurological (73.3%) and non-neurological COVID-hospitalised controls (76.6%) in contrast to the COVID-non-hospitalised controls (48.2%). aPS/PT IgG titres were significantly higher in the COVID-neurological group compared to both control groups (p < 0.001). Moderate-high titre of aPS/PT IgG was found in 2 out of 3 (67%) patients with acute disseminated encephalomyelitis [ADEM]. aPS/PT IgG titres negatively correlated with oxygen requirement (FiO2 R=-0.15 p = 0.040) and was associated with venous thromboembolism (p = 0.043). In contrast, aCL IgA (p < 0.001) and IgG (p < 0.001) was associated with non-neurological COVID-hospitalised controls compared to the other groups and correlated positively with d-dimer and creatinine but negatively with FiO2.

INTERPRETATION

Our findings show that aPS/PT IgG is associated with COVID-19-associated ADEM. In contrast, aCL IgA and IgG are seen much more frequently in non-neurological hospitalised patients with COVID-19. Characterisation of antiphospholipid antibody persistence and potential longitudinal clinical impact are required to guide appropriate management.

FUNDING

This work is supported by UCL Queen Square Biomedical Research Centre (BRC) and Moorfields BRC grants (#560441 and #557595). LB is supported by a Wellcome Trust Fellowship (222102/Z/20/Z). RWP is supported by an Alzheimer's Association Clinician Scientist Fellowship (AACSF-20-685780) and the UK Dementia Research Institute. KB is supported by the Swedish Research Council (#2017-00915) and the Swedish state under the agreement between the Swedish government and the County Councils, the ALF-agreement (#ALFGBG-715986). HZ is a Wallenberg Scholar supported by grants from the Swedish Research Council (#2018-02532), the European Research Council (#681712), Swedish State Support for Clinical Research (#ALFGBG-720931), the Alzheimer Drug Discovery Foundation (ADDF), USA (#201809-2016862), and theUK Dementia Research Institute at UCL. BDM is supported by grants from the MRC/UKRI (MR/V007181/1), MRC (MR/T028750/1) and Wellcome (ISSF201902/3). MSZ, MH and RS are supported by the UCL/UCLH NIHR Biomedical Research Centre and MSZ is supported by Queen Square National Brain Appeal.

Clinical review of cerebral venous thrombosis in the context of COVID-19 vaccinations: Evaluation, management, and scientific questions

BACKGROUND

Vaccine induced immune mediated thrombocytopenia or VITT, is a recent and rare phenomenon of thrombosis with thrombocytopenia, frequently including cerebral venous thromboses (CVT), that has been described following vaccination with adenovirus vaccines ChAdOx1 nCOV-19 (AstraZeneca) and Ad26.COV2·S Johnson and Johnson (Janssen/J&J). The evaluation and management of suspected cases of CVT post COVID-19 vaccination are critical skills for a broad range of healthcare providers.

METHODS

A collaborative comprehensive review of literature was conducted among a global group of expert neurologists and hematologists.

FINDINGS

Strategies for rapid evaluation and treatment of the CVT in the context of possible VITT exist, including inflammatory marker measurements, PF4 assays, and non-heparin anticoagulation.

Spectrum, risk factors and outcomes of neurological and psychiatric complications of COVID-19: a UK-wide cross-sectional surveillance study

SARS-CoV-2 is associated with new-onset neurological and psychiatric conditions. Detailed clinical data, including factors associated with recovery, are lacking, hampering prediction modelling and targeted therapeutic interventions. In a UK-wide cross-sectional surveillance study of adult hospitalized patients during the first COVID-19 wave, with multi-professional input from general and sub-specialty neurologists, psychiatrists, stroke physicians, and intensivists, we captured detailed data on demographics, risk factors, pre-COVID-19 Rockwood frailty score, comorbidities, neurological presentation and outcome. A priori clinical case definitions were used, with cross-specialty independent adjudication for discrepant cases. Multivariable logistic regression was performed using demographic and clinical variables, to determine the factors associated with outcome. A total of 267 cases were included. Cerebrovascular events were most frequently reported (131, 49%), followed by other central disorders (95, 36%) including delirium (28, 11%), central inflammatory (25, 9%), psychiatric (25, 9%), and other encephalopathies (17, 7%), including a severe encephalopathy (n = 13) not meeting delirium criteria; and peripheral nerve disorders (41, 15%). Those with the severe encephalopathy, in comparison to delirium, were younger, had higher rates of admission to intensive care and a longer duration of ventilation. Compared to normative data during the equivalent time period prior to the pandemic, cases of stroke in association with COVID-19 were younger and had a greater number of conventional, modifiable cerebrovascular risk factors. Twenty-seven per cent of strokes occurred in patients <60 years. Relative to those >60 years old, the younger stroke patients presented with delayed onset from respiratory symptoms, higher rates of multi-vessel occlusion (31%) and systemic thrombotic events. Clinical outcomes varied between disease groups, with cerebrovascular disease conferring the worst prognosis, but this effect was less marked than the pre-morbid factors of older age and a higher pre-COVID-19 frailty score, and a high admission white cell count, which were independently associated with a poor outcome. In summary, this study describes the spectrum of neurological and psychiatric conditions associated with COVID-19. In addition, we identify a severe COVID-19 encephalopathy atypical for delirium, and a phenotype of COVID-19 associated stroke in younger adults with a tendency for multiple infarcts and systemic thromboses. These clinical data will be useful to inform mechanistic studies and stratification of patients in clinical trials.

Lacosamide add-on therapy for focal epilepsy

BACKGROUND

This is an updated version of the Cochrane review published in 2015. Around half of people with epilepsy will not achieve seizure freedom on their first antiepileptic drug; many will require add-on therapy. Around a third of people fail to achieve complete seizure freedom despite multiple antiepileptic drugs. Lacosamide has been licenced as an add-on therapy for drug-resistant focal epilepsy.

OBJECTIVES

To evaluate the efficacy and tolerability of lacosamide as an add-on therapy for children and adults with drug-resistant focal epilepsy.

SEARCH METHODS

We searched the following databases (22 August 2019): the Cochrane Register of Studies (CRS Web), including the Cochrane Epilepsy Group Specialized Register and the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (Ovid, 1946 to 20 August 2019), ClinicalTrials.gov, and the WHO International Clinical Trials Registry Platform (ICTRP), with no language restrictions. We contacted UCB Pharma (sponsors of lacosamide).

SELECTION CRITERIA

Randomised controlled trials of add-on lacosamide in people with drug-resistant focal epilepsy.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology, assessing the following outcomes: 50% or greater reduction in seizure frequency; seizure freedom; treatment withdrawal; adverse events; quality of life; and cognitive changes. The primary analyses were intention-to-treat. We estimated summary risk ratios (RR) for each outcome presented with 99% confidence intervals (CI), except for 50% or greater seizure reduction, seizure freedom and treatment withdrawal which were presented with 95% CIs. We performed subgroup analyses according to lacosamide dose and sensitivity analyses according to population age, whereby data from children were excluded from the meta-analysis.

MAIN RESULTS

We included five trials (2199 participants). The risk of bias for all studies was low to unclear. All studies were placebo-controlled and assessed doses from 200 mg to 600 mg per day. One study evaluated lacosamide in children; all other studies were in adults. Trial duration ranged from 24 to 26 weeks. All studies used adequate methods of randomisation and were double-blind. Overall, the certainty of the evidence for the outcomes was judged as moderate to high, with the exception of seizure freedom which was low. The RR for a 50% or greater reduction in seizure frequency for all doses of lacosamide compared with placebo was 1.79 (95% CI 1.55 to 2.08; 5 studies; 2199 participants; high-certainty evidence). The RR for seizure freedom for all doses of lacosamide compared with placebo was 2.27 (95% CI 1.35 to 3.83; 5 studies; 2199 participants; low-certainty evidence). The RR for treatment withdrawal for all doses of lacosamide compared with placebo was 1.57 (95% CI 1.24 to 1.98; 5 studies; 2199 participants; moderate-certainty evidence). The estimated effect size for most outcomes did not change considerably following sensitivity analysis. For seizure freedom, however, the RR nearly doubled upon the exclusion of data from children (RR 4.04, 95% CI 1.52 to 10.73). Adverse events associated with lacosamide included: abnormal co-ordination (RR 6.12, 99% CI 1.35 to 27.77), blurred vision (RR 4.65, 99% CI 1.24 to 17.37), diplopia (RR 5.59, 99% CI 2.27 to 13.79), dizziness (RR 2.96, 99% CI 2.09 to 4.20), nausea (RR 2.35, 99% CI 1.37 to 4.02), somnolence (RR 2.04, 99% CI 1.22 to 3.41), vomiting (RR 2.94, 99% CI 1.54 to 5.64), and number of participants experiencing one or more adverse events (RR 1.12, 99% CI 1.01 to 1.24). Adverse events that were not significant were: vertigo (RR 3.71, 99% CI 0.86 to 15.95), rash (RR 0.58, 99% CI 0.17 to 1.89), nasopharyngitis (RR 1.41, 99% CI 0.87 to 2.28), headache (RR 1.34, 99% CI 0.90 to 1.98), fatigue (RR 2.11, 99% CI 0.92 to 4.85), nystagmus (RR 1.47, 99% CI 0.61 to 3.52), and upper respiratory tract infection (RR 0.70, 99% CI 0.43 to 1.15).

AUTHORS' CONCLUSIONS

Lacosamide is effective and well-tolerated in the short term when used as add-on treatment for drug-resistant focal epilepsy. Lacosamide increases the number of people with 50% or greater reduction in seizure frequency and may increase seizure freedom, compared to placebo. Higher doses of lacosamide may be associated with higher rates of adverse events and treatment withdrawal. Additional evidence is required assessing the use of lacosamide in children and on longer-term efficacy and tolerability.

Update on the diagnosis and management of autoimmune encephalitis

In recent years, autoimmunity has been increasingly recognised as an important cause of encephalitis. Many different antibodies are now known to target antigens on the neuronal surface, and some of these are associated with characteristic clinical presentations, although seronegative cases are also recognised. Autoimmune encephalitis may mimic other conditions, including primary psychiatric disorders, particularly early in the disease. Because early immune treatment of autoimmune encephalitis improves patient outcomes, and indeed many make a good recovery, it is important to recognise these syndromes promptly.

Astrocyte- and Neuron-Derived CXCL1 Drives Neutrophil Transmigration and Blood-Brain Barrier Permeability in Viral Encephalitis

Herpes simplex virus (HSV)-1 encephalitis has significant morbidity partly because of an over-exuberant immune response characterized by leukocyte infiltration into the brain and increased blood-brain barrier (BBB) permeability. Determining the role of specific leukocyte subsets and the factors that mediate their recruitment into the brain is critical to developing targeted immune therapies. In a murine model, we find that the chemokines CXCL1 and CCL2 are induced in the brain following HSV-1 infection. Ccr2 (CCL2 receptor)-deficient mice have reduced monocyte recruitment, uncontrolled viral replication, and increased morbidity. Contrastingly, Cxcr2 (CXCL1 receptor)-deficient mice exhibit markedly reduced neutrophil recruitment, BBB permeability, and morbidity, without influencing viral load. CXCL1 is produced by astrocytes in response to HSV-1 and by astrocytes and neurons in response to IL-1α, and it is the critical ligand required for neutrophil transendothelial migration, which correlates with BBB breakdown. Thus, the CXCL1-CXCR2 axis represents an attractive therapeutic target to limit neutrophil-mediated morbidity in HSV-1 encephalitis.

Transcranial magnetic stimulation for the treatment of epilepsy

BACKGROUND

Epilepsy is a highly prevalent neurological condition characterised by repeated unprovoked seizures with various aetiologies. Although antiepileptic medications produce clinical improvement in many individuals, nearly a third of individuals have drug-resistant epilepsy that carries significant morbidity and mortality, and even individuals who have clinical improvement from antiepileptic medications often report iatrogenic symptoms. There remains a need for non-invasive and more effective therapies for this population. Transcranial magnetic stimulation (TMS) uses electromagnetic coils to excite or inhibit neurons, with repetitive pulses at low-frequency producing an inhibitory effect that could conceivably reduce cortical excitability associated with epilepsy. This is an updated version of the original Cochrane Review published in 2016.

OBJECTIVES

To assess the evidence for the use of TMS in individuals with drug-resistant epilepsy compared with other available treatments in reducing seizure frequency, improving quality of life, reducing epileptiform discharges, antiepileptic medication use, and side effects.

SEARCH METHODS

For the latest update, we searched the Cochrane Register of Studies (CRS Web) and MEDLINE (Ovid 1946 to 2 June 2020). CRS Web includes randomised or quasi-randomised controlled trials from PubMed, Embase, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), the Cochrane Central Register of Controlled Trials (CENTRAL), and the specialised registers of Cochrane Review Groups including Epilepsy.

SELECTION CRITERIA

We included randomised controlled trials that were double-blinded, single-blinded, or unblinded, and placebo controlled, no treatment, or active controlled, which used repetitive transcranial magnetic stimulation (rTMS) without restriction of frequency, coil, duration or intensity on participants with drug-resistant epilepsy.

DATA COLLECTION AND ANALYSIS

We extracted information from each trial including methodological data; participant demographics including baseline seizure frequency, type of epileptic drugs taken; intervention details and intervention groups for comparison; potential biases; and outcomes and time points, primarily change in seizure frequency or responder rates, as well as quality of life and epileptiform discharges, adverse effects, and changes in medication use.

MAIN RESULTS

The original search revealed 274 records from the databases that after selection provided seven full-text relevant studies for inclusion. The latest search identified 179 new records from the databases that after evaluation against the inclusion and exclusion criteria provided one additional full-text relevant study. The eight included studies (241 participants) were all randomised trials; seven of the studies were blinded. Methodological and design information in the included studies was unclear, particularly relating to randomisation and allocation concealment methods. We were not able to combine the results of the trials in analysis due to differences in the studies' designs. For the current update, two of the eight studies analysed showed a statistically significant reduction in seizure rate from baseline (72% and 78.9% reduction of seizures per week from the baseline rate, respectively), whilst the other six studies showed no statistically significant difference in seizure frequency following rTMS treatment compared with controls (low-certainty evidence). One study assessed quality of life and found that more participants showed improvement in quality of life scores with active treatments compared to the sham treatment, but this only involved seven participants (very low-certainty evidence). Four studies evaluated our secondary endpoint of mean number of epileptic discharges, three of which showed a statistically significant reduction in discharges after active rTMS treatment. Adverse effects were uncommon in the studies and typically involved headache, dizziness, and tinnitus; however increased seizure frequency did occur in a small number of individuals. The included trials reported no significant changes in medication use. Overall the risk of bias was either low or unclear, and the certainty of the evidence was low to very low.

AUTHORS' CONCLUSIONS

Overall, we judged the certainty of evidence for the primary outcomes of this review to be low to very low. We found some evidence to suggest that rTMS is safe but some adverse events were experienced. The variability in technique and outcome reporting prevented meta-analysis, and the evidence for efficacy of rTMS for seizure reduction is still lacking, despite reasonable evidence that it is effective at reducing epileptiform discharges.

Approaches to understanding COVID-19 and its neurological associations

There is an accumulating volume of research into neurological manifestations of COVID-19. However, inconsistent study designs, inadequate controls, poorly-validated tests, and differing settings, interventions, and cultural norms weaken study quality, comparability, and thus the understanding of the spectrum, burden and pathophysiology of these complications. Therefore, a global COVID-19 Neuro Research Coalition, together with the WHO, has reviewed reports of COVID-19 neurological complications and harmonised clinical measures for future research. This will facilitate well-designed studies using precise, consistent case definitions of SARS-CoV2 infection and neurological complications, with standardised forms for pooled data analyses that non-specialists can use, including in low-income settings. This article is protected by copyright. All rights reserved.

Neurological and neuropsychiatric complications of COVID-19 in 153 patients: a UK-wide surveillance study

BACKGROUND

Concerns regarding potential neurological complications of COVID-19 are being increasingly reported, primarily in small series. Larger studies have been limited by both geography and specialty. Comprehensive characterisation of clinical syndromes is crucial to allow rational selection and evaluation of potential therapies. The aim of this study was to investigate the breadth of complications of COVID-19 across the UK that affected the brain.

METHODS

During the exponential phase of the pandemic, we developed an online network of secure rapid-response case report notification portals across the spectrum of major UK neuroscience bodies, comprising the Association of British Neurologists (ABN), the British Association of Stroke Physicians (BASP), and the Royal College of Psychiatrists (RCPsych), and representing neurology, stroke, psychiatry, and intensive care. Broad clinical syndromes associated with COVID-19 were classified as a cerebrovascular event (defined as an acute ischaemic, haemorrhagic, or thrombotic vascular event involving the brain parenchyma or subarachnoid space), altered mental status (defined as an acute alteration in personality, behaviour, cognition, or consciousness), peripheral neurology (defined as involving nerve roots, peripheral nerves, neuromuscular junction, or muscle), or other (with free text boxes for those not meeting these syndromic presentations). Physicians were encouraged to report cases prospectively and we permitted recent cases to be notified retrospectively when assigned a confirmed date of admission or initial clinical assessment, allowing identification of cases that occurred before notification portals were available. Data collected were compared with the geographical, demographic, and temporal presentation of overall cases of COVID-19 as reported by UK Government public health bodies.

FINDINGS

The ABN portal was launched on April 2, 2020, the BASP portal on April 3, 2020, and the RCPsych portal on April 21, 2020. Data lock for this report was on April 26, 2020. During this period, the platforms received notification of 153 unique cases that met the clinical case definitions by clinicians in the UK, with an exponential growth in reported cases that was similar to overall COVID-19 data from UK Government public health bodies. Median patient age was 71 years (range 23-94; IQR 58-79). Complete clinical datasets were available for 125 (82%) of 153 patients. 77 (62%) of 125 patients presented with a cerebrovascular event, of whom 57 (74%) had an ischaemic stroke, nine (12%) an intracerebral haemorrhage, and one (1%) CNS vasculitis. 39 (31%) of 125 patients presented with altered mental status, comprising nine (23%) patients with unspecified encephalopathy and seven (18%) patients with encephalitis. The remaining 23 (59%) patients with altered mental status fulfilled the clinical case definitions for psychiatric diagnoses as classified by the notifying psychiatrist or neuropsychiatrist, and 21 (92%) of these were new diagnoses. Ten (43%) of 23 patients with neuropsychiatric disorders had new-onset psychosis, six (26%) had a neurocognitive (dementia-like) syndrome, and four (17%) had an affective disorder. 18 (49%) of 37 patients with altered mental status were younger than 60 years and 19 (51%) were older than 60 years, whereas 13 (18%) of 74 patients with cerebrovascular events were younger than 60 years versus 61 (82%) patients older than 60 years.

INTERPRETATION

To our knowledge, this is the first nationwide, cross-specialty surveillance study of acute neurological and psychiatric complications of COVID-19. Altered mental status was the second most common presentation, comprising encephalopathy or encephalitis and primary psychiatric diagnoses, often occurring in younger patients. This study provides valuable and timely data that are urgently needed by clinicians, researchers, and funders to inform immediate steps in COVID-19 neuroscience research and health policy.

FUNDING

None.