Long-Term Outcomes and Risk Factors Associated With Acute Encephalitis in Children

Clinical Outcome Assessments in Encephalitis: A Systematic Review

BACKGROUND AND OBJECTIVES

Most patients with encephalitis experience persisting neurocognitive and neuropsychiatric sequelae in the years following this acute illness. Reported outcomes are often based on generic clinical outcome assessments that rarely capture the patient perspective. This may result in an underestimation of disease-specific sequelae. Disease-specific clinical outcome assessments can improve clinical relevance of reported outcomes and increase the power of research and trials. There are no patient-reported outcome measures (PROMs) developed or validated specifically for patients with encephalitis. The primary objective of this systematic literature review was to identify PROMs that have been developed for or validated in patients with encephalitis.

METHODS

We performed a systematic review of the literature published from inception until May 2023 in 3 large international databases (MEDLINE, EMBASE and Cochrane libraries). Eligible studies should have developed or validated a PROM in patients with encephalitis or encephalopathy. Methodologic quality was evaluated using the Consensus-based Standards for the selection of health status Measurement Instruments study design checklist for PROMs.

RESULTS

We identified no disease-specific PROMs developed or validated for patients with encephalitis. We identified one study on the development and validation of a disease-specific PROM for hepatic encephalopathy, although this disease course is substantially different to that of patients with encephalitis. The methodologic quality of the included study was generally rated as "doubtful." We identified 30 PROMs that have been applied in 46 studies on encephalitis or encephalopathy, although not validated in these populations. The most commonly applied PROMs for measuring Health-Related Quality of Life were the Medical Outcomes Study Short Form-36 and the Sickness Impact Profile. Emotional well-being was often assessed with the Beck Depression Inventory (BDI-II). Sporadically, PROMs were applied to address other aspects of outcome including daily functioning and sleep quality.

DISCUSSION

This systematic review confirms a critical gap in clinical outcome assessments in patients with encephalitis, failing to identify a validated measuring tool for detecting neurocognitive, functional, and health status. It is therefore essential to develop and/or validate disease-specific PROMs for the population with encephalitis to capture relevant information for patient management and clinical trials about the effects of disease that are at risk of being overlooked.

Neurotropic enteroviruses (Picornaviridae: Enterovirus): predominant types, basis of neurovirulence

Enteroviruses are one of the most common causative agents of infectious diseases of the central nervous system. They are characterized by genetic variability, the ability to infect a wide range of cells, including brain microglial cells and astrocytes, and persist in the central nervous system tissue, causing delayed and chronic diseases. The review presents data on the basis of neurovirulence of non-polio enteroviruses and the most common pathogens causing enteroviral neuroinfections.

Neurocognitive outcome in children and adolescents following infectious encephalitis

Infectious encephalitis in children is fairly uncommon, but unfavorable outcomes are seen in many survivors. The aim of this study was to prospectively describe the long-term neurocognitive consequences following infectious encephalitis in childhood. Children admitted to a primary and tertiary hospital in Sweden between 2011 and 2016 were asked to participate. Fifty-nine children were assessed at a median time of 18 months (IQR 18-20) after hospitalization. Follow-up included measures of intellectual functioning, attention, working memory, and executive functions. Caregiver ratings of executive functioning and behavioral - emotional symptoms were assessed with standardized questionnaires. Neurocognitive outcome and measures of executive functions and behavioral-emotional symptoms varied greatly among participants. Basic auditory attention, working memory, and mental processing speed were affected and significantly lower compared to a standardized mean. Other domains identified as areas of vulnerability included executive functions, sustained attention, and the exert of self-control. Behavioral-emotional symptoms were less common; however, somatic complaints and behaviors related to conduct problems were seen in about one-third of individuals. This study highlights the importance of a comprehensive neurocognitive examination to identify children with unfavorable outcomes.

Severe encephalitis: aetiology, management and outcomes over 10 years in a paediatric intensive care unit

OBJECTIVE

To describe the characteristics, differential diagnoses, management and outcomes of severe encephalitis in children.

DESIGN

A 10-year retrospective cohort study in children admitted to a tertiary paediatric intensive care unit (PICU) with suspected encephalitis. One to 6 months' follow-up data were compared between different categories.

PARTICIPANTS

Patients from 0 to 17 years of age with acute encephalopathy and one or more of fever, seizure, focal neurological findings, cerebrospinal fluid abnormalities, EEG/neuroimaging consistent with encephalitis.

MAIN OUTCOME MEASURES

Epidemiology, clinical features, outcomes and risk factor analysis.

RESULTS

175 children with encephalitis required intensive care unit (ICU) admission over 10 years. The median age was 4.5 months (IQR 1.6-54.8). The leading cause was enterovirus (n=49, 28%), followed by parechovirus, influenza, herpes simplex virus (HSV), human herpesvirus-6 (HHV-6), Streptococcus pneumoniae, acute-disseminated encephalomyelitis and anti-N-methyl-D-aspartate-receptor-associated encephalitis. Immune-mediated encephalitis had higher prevalence in females, older age and longer duration of encephalopathy. Mechanical ventilation was required by 74 children (42%); haemodynamic support by 28 children (16%), 3 received extracorporeal membrane oxygenation (ECMO) support. Eleven patients died (case fatality rate 6.3%): five with HHV-6, two enterovirus, two influenza, one HSV, one human-metapneumovirus. At follow-up, 34 children had mild or moderate disability, and six severe disability. In a multivariable logistic regression model, three factors were associated with severe disability or death: age <2 years old (OR 8.2, CI 1.0 to 67.2), Herpesviridae aetiology (OR 14.5, CI 1.2 to 177.3) and length of intubation (OR 1.005, CI 1.00 to 1.01).

CONCLUSIONS

Encephalitis has a varied aetiology and causes death or severe disability in 1 in every 10 children requiring intensive care.

Public economic gains from tax-financed investments in childhood immunization in the United States

The emergence of COVID-19 has displayed the importance of immunization and the need for continued public investment in vaccination programs. Globally, national vaccination programs rely heavily on tax-financed expenditure, requiring upfront investments and ongoing financial commitments. To evaluate annual public investments, we conducted a fiscal analysis that quantifies the public economic consequences to government in the United States attributable to childhood vaccination. To estimate the change in net government revenue, we developed a decision-analytic model that quantifies lifetime tax revenues and transfers based on changes in morbidity and mortality arising from vaccination of the 2017 U.S. birth cohort. Reductions in deaths and comorbid conditions attributed to pediatric vaccines were used to derive gross lifetime earnings gains, tax revenue gains attributed to averted morbidity and mortality avoided, disability transfer cost savings, and averted special education costs associated with each vaccine. Our analysis indicates a fiscal dividend of $41.7 billion from vaccinating this cohort. The bulk of this gain for government reflects avoiding the loss of $30.6 billion in present-value tax revenues. All pediatric vaccines raise tax revenues by reducing vaccine-preventable morbidity and mortality in amounts ranging from $7.3 million (hepatitis A) to $20.3 billion (diphtheria) over the life course. Based on public investments in pediatric vaccines, a benefit-cost ratio of 17.8 was calculated for each dollar invested in childhood immunization. The public economic yield attributed to childhood vaccination in the U.S. is significant from a government perspective, providing fiscal justification for ongoing investment.

Perturbations in neural stem cell function during a neurotropic viral infection in juvenile mice

Viral infections of the central nervous system (CNS) often cause worse neurological outcomes in younger hosts. Throughout childhood, the brain undergoes extensive development and refinement to produce functional neural networks. Network function is maintained partly with the help of neural stem cells (NSCs) that replace neuronal and glia subtypes in the two neurogenic niches of the brain (the hippocampus and subventricular zone). Accumulating evidence suggests that viruses disrupt NSC function in adulthood and infancy, but the in vivo impact of childhood infections on acute and long-term NSC function is unknown. Using a juvenile mouse model of measles virus (MeV) infection, where only mature neurons in the brain are infected, we defined the effects of the antiviral immune response on NSCs from juvenile to adult stages of life. We found that (a) virus persists in the brains of survivors despite an anti-viral immune response; (b) NSC numbers decrease dramatically during early infection, but ultimately stabilize in adult survivors; (c) infection is associated with mild apoptosis throughout the juvenile brain, but NSC proliferation is unchanged; (d) the loss of NSC numbers is dependent upon the stage of NSC differentiation; and (e) immature neurons increase early during infection, concurrent with depletion of NSC pools. Collectively, we show that NSCs are exquisitely sensitive to the inflammatory microenvironment created during neuron-restricted MeV infection in juveniles, responding with an early loss of NSCs but increased neurogenesis. These studies provide insight into potential cellular mechanisms associated with long-term neurological deficits in survivors of childhood CNS infections.

Evaluation, Treatment, and Outcomes of Viral and Autoimmune Encephalitis in Children

Viral encephalitis and autoimmune encephalitis are currently the most common causes of encephalitis. Determining the causative agent is helpful in initiating medical treatment that may help reduce long-term sequelae. Cerebrospinal fluid, neuroimaging, serologic, and electroencephalogram in combination with clinical manifestations play a role in determining the cause of the encephalitis. Although motor dysfunction tends to improve, there is a significant risk of long-term neurologic and cognitive sequelae. These persistent deficits that occur in childhood indicate the importance for ongoing rehabilitative services to maximize functional skills, improve cognitive deficits, and assist with community integration.

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.

La Crosse Virus Neuroinvasive Disease in Children: A Contemporary Analysis of Clinical/Neurobehavioral Outcomes and Predictors of Disease Severity

BACKGROUND

La Crosse virus (LACV) is the most common neuroinvasive arboviral infection in children in the United States. However, data regarding predictors of disease severity and neurologic outcome are limited. Additionally, long-term neurologic and neurobehavioral outcomes remain relatively sparse.

METHODS

This was a single-center, retrospective cohort study, followed by recruitment for a cross-sectional analysis of long-term neurobehavioral outcomes, among children aged 0-18 years with proven or probable LACV neuroinvasive disease (LACV-ND) between January 2009 and December 2018. Case ascertainment was assured by International Classification of Diseases, Ninth and Tenth Revision, Clinical Modification codes cross-referenced with laboratory results detecting LACV. Demographics, diagnostics, radiographs, and outcomes were evaluated. Recruitment of patients with prior diagnosis of LACV-ND occurred from January 2020 to March 2020, with assessment performed by validated pediatric questionnaires.

RESULTS

One-hundred fifty-two children (83 males; median age, 8 years [interquartile range, 5-11.5 years]) were diagnosed with proven (n = 61 [47%]) and probable (n = 91 [60%]) LACV-ND. Sixty-five patients (43%) had severe disease. Altered mental status (AMS) (odds ratio [OR], 6.36 [95% confidence interval {CI}, 2.03-19.95]; P = .0002) and seizures at presentation (OR, 10.31 [95% CI, 3.45-30.86]; P = .0001) were independent predictors of severe disease. Epileptiform discharges on electroencephalogram (EEG) were independently associated with epilepsy diagnosis at follow-up (OR, 13.45 [95% CI, 1.4-128.77]; P = .024). Fifty-four patients were recruited for long-term neurobehavioral follow-up, with frequent abnormal assessments identified (19%-54%) irrespective of disease severity.

CONCLUSIONS

Severe disease was observed frequently among children with LACV-ND. Seizures and AMS at presentation were independent predictors of severe disease. EEG may help determine long-term epilepsy risk. Long-term neurobehavioral issues are frequent and likely underrecognized among children with LACV-ND.

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.

The Clinical, Radiological, and Electrophysiological Profile of Children Presenting with Acute Fulminant Cerebral Edema Due to Suspected Encephalitis in an Eastern Indian Tertiary Care Center

Objective Our objective was to describe the clinicodemographic, laboratory, and outcome profiles of a rare phenotype of pediatric acute encephalitis syndrome (AES) with acute fulminant cerebral edema (AFCE) and compare them with that of AES without AFCE.

Methods We retrospectively analyzed medical records of a cluster of children hospitalized with encephalitis between June 1, 2021 and December 31, 2021. Their clinical and demographic features, laboratory investigations (hematological, biochemical, serological, microbiological, radiological, and electrophysiological tests), and follow-up data up to 3 months postdischarge were recorded. Patients with AFCE and those without it were divided into groups A and B, respectively, and their characteristics were compared.

Results There were 11 and 15 patients in groups A and B, respectively. There were no significant differences between the two groups in terms of sex, neurological status at admission, hematological and cerebrospinal fluid values, pediatric intensive care unit (PICU) course, and management, etiological identification, and mortality and disabilities at discharge. Patients having reversal or having white cerebellar signs did not significantly differ in their outcomes. However, the patients in group A had significantly lower age, higher incidence of abnormal findings on head computed tomography scans at admission, longer duration of hospitalization, and neurological sequelae at 3 months. The numbers of patients with identified etiologies were zero in group A but five in group B (two Japanese encephalitis, two scrub typhus, and one dengue). Patients of group A had bilateral asymmetric temporal-parieto-occipital T2 hyperintense lesions in magnetic resonance imaging, whereas patients of group B had bifrontal predominant or thalamo-mesencephalic lesions. Multifocal epileptiform discharges were seen in electroencephalogram in both groups, which reverted to normal in 9 and 46% in groups A and B at 3 months, respectively.

Conclusion Younger age is a significant risk factor for the development of AFCE in pediatric AES. AFCE patients have worse outcomes at 3 months, although they do not significantly differ from their non-AFCE counterparts at discharge. When occurring in clusters, AFCE patients exhibit the same radiological and electroencephalographic features.

Neuroimaging and neurological outcome of children with acute encephalitis

AIM

To investigate the severity of acute phase magnetic resonance imaging (MRI) findings and severity of acute illness as risk factors for disability after recovery from encephalitis.

METHOD

Children with encephalitis (n = 98; median age 6 years 10 months, interquartile range 3 years-11 years 6 months; 59 males, 39 females) treated in Turku University Hospital during the years 1995 to 2016 were identified in this retrospective cohort study. The acute phase (<2 months of symptom onset) brain MRIs were re-evaluated and classified based on the severity of neuroimaging finding by a neuroradiologist. Neurological outcome at discharge, at short-term (<3 months from discharge) follow-up, and at long-term (>1 year from discharge) follow-up was assessed from medical records using the Glasgow Outcome Scale.

RESULTS

Long-term recovery was poor in 24 of 82 (29%) children with follow-up data. Two children died, eight had severe disability, and 14 had moderate disability. Acute phase MRI was available for re-evaluation from 74 of 82 patients with follow-up data. The increasing severity of MRI findings was associated with need for ventilator therapy and with poor recovery.

INTERPRETATION

The risk for poor recovery in paediatric encephalitis is high, and it is associated with the severity of MRI findings.

WHAT THIS PAPER ADDS

Poor long-term recovery was found in 29% of children with encephalitis. Severe disability measured by Glasgow Outcome Scale was found in 8%. The most severe neuroimaging findings were a risk factor for severe acute illness and poor long-term recovery.

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.

Cerebral injuries in neonatal encephalopathy treated with hypothermia: French LyTONEPAL cohort

BACKGROUND

Hypothermia is widely used for infants with hypoxic-ischemic neonatal encephalopathy but its impact remains poorly described at a population level. We aimed to describe brain imaging in infants born at ≥36 weeks' gestation, with moderate/severe encephalopathy treated with hypothermia.

METHODS

Descriptive analysis of brain MRI and discharge neurological examination for infants included in the French national multicentric prospective observational cohort LyTONEPAL.

RESULTS

Among 575 eligible infants, 479 (83.3%) with MRI before 12 days of life were included. MRI was normal for 48.2% (95% CI 43.7-52.8). Among infants with brain injuries, 62.5% (95% CI 56.2-68.5) had damage to more than one structure, 19.8% (95% CI 15.0-25.3) showed a pattern-associating injuries of basal ganglia/thalami (BGT), white matter (WM) and cortex. Overall, 68.4% (95% CI 62.0-74.3) of infants with normal MRI survived with a normal neurological examination. The rate of death was 15.4% (95% CI 12.3-19.0), predominantly for infants with the combined BGT, cortex, and/or WM injuries.

CONCLUSIONS

Among infants with neonatal encephalopathy treated with hypothermia, two-thirds of those with normal MRI survived with a normal neurological examination at discharge. When present, brain injuries often involved more than one structure.

TRIAL REGISTRATION

The trial was registered at ClinicalTrials.gov (NCT02676063).

IMPACT

In this multicentric cohort of infants with neonatal encephalopathy (LYTONEPAL) two-thirds survived with normal MRI and neurological examination at discharge. In total, 10% of newborns showed a pattern associating injuries of the basal ganglia-thalami, white matter, and cortex, which was correlated with a high risk of death at discharge. The evolution of MRI techniques and sequences in the era of hypothermia calls for a revisiting of imaging protocol in neonatal encephalopathy, especially for the timing. The neurological examination did not give evidence of brain injuries, thus questioning the reproducibility of the clinical exam or the neonatal brain functionality.

An Updated Overview of MRI Injuries in Neonatal Encephalopathy: LyTONEPAL Cohort

Background: Brain magnetic resonance imaging (MRI) is a key tool for the prognostication of encephalic newborns in the context of hypoxic−ischemic events. The purpose of this study was to finely characterize brain injuries in this context. Methods: We provided a complete, descriptive analysis of the brain MRIs of infants included in the French national, multicentric cohort LyTONEPAL. Results: Among 794 eligible infants, 520 (65.5%) with MRI before 12 days of life, grade II or III encephalopathy and gestational age ≥36 weeks were included. Half of the population had a brain injury (52.4%); MRIs were acquired before 6 days of life among 247 (47.5%) newborns. The basal ganglia (BGT), white matter (WM) and cortex were the three predominant sites of injuries, affecting 33.8% (n = 171), 33.5% (n = 166) and 25.6% (n = 128) of participants, respectively. The thalamus and the periventricular WM were the predominant sublocations. The BGT, posterior limb internal capsule, brainstem and cortical injuries appeared more frequently in the early MRI group than in the late MRI group. Conclusion: This study described an overview of brain injuries in hypoxic−ischemic neonatal encephalopathy. The basal ganglia with the thalamus and the WM with periventricular sublocation injuries were predominant. Comprehensive identification of brain injuries in the context of HIE may provide insight into the mechanism and time of occurrence.

Etiological and Clinical Profile of Acute Nonbacterial Encephalitis in Children: A Single-Center Prospective Study

Encephalitis is a serious neurological syndrome caused by inflammation of the brain. The diagnosis can be challenging and etiology remains unidentified in about half of the pediatric cases. We aimed to investigate demographic, clinical, laboratory, electroencephalographic and neuroimaging findings, and outcome of acute encephalitis of nonbacterial etiology. This prospective study included children hospitalized with the diagnosis of acute encephalitis between 2017 and 2019. Microbiological investigations of the cerebrospinal fluid (CSF) were recorded. All CSF specimens were tested for anti-N methyl D-aspartate receptor (NMDAR) antibodies. In total, 31 children aged 10 months to 17 years (median = 6 years) were included. Pathogens were confirmed in CSF in three patients (9.7%): varicella zoster virus, herpes simplex virus type 1 (HSV-1), and both HSV-1 and NMDAR antibodies. Presenting features included encephalopathy (100%), fever (80.6%), seizure (45.2%), focal neurological signs (29%), and ataxia (19.4%). On clinical follow-up of median 9 (6-24) months, six patients showed neurological deficits: together with two patients who died in hospital, total eight (25.8%) patients were considered to have unfavorable outcome. Need for intubation, receiving immunomodulatory treatment, prolonged hospitalization, and high erythrocyte sedimentation rate at admission were associated with unfavorable outcome. The etiology of encephalitis remains unexplained in the majority of children. HSV-1 is the most frequently detected virus, consistent with the literature. The fact that anti-NMDAR encephalitis was detected in one child suggests autoimmune encephalitis not being rare in our center. The outcome is favorable in the majority while about one-fifth of cases suffer from sequelae.

Diagnosis and Therapy of Infectious Encephalitis in Children: A Ten-Years Retrospective Study

BACKGROUND

Infectious encephalitis represents a rare but potentially severe clinical condition. However, limited international data are available in pediatric age.

METHODS

We conducted a retrospective study to review (a) the clinical presentation; (b) laboratory, radiology, and neurophysiology findings; (c) the correlations between these exams and outcome; and (d) the therapy performed.

RESULTS

Fifty-six patients were enrolled [22 female (39.6%), mean age 4.7 years, IQR 0.7-8.7 years], 19.6% presented neurologic sequelae. HSV was the single most frequently isolated pathogen (19.6%), although in most cases, the etiology remained undefined. 41.1% children presented prodromal before the development of neurologic signs. Fever was the most frequent constitutional symptom (83.9% of cases). Cerebrospinal fluid was normal in 48.5% of cases and electroencephalograpy in 24.5% cases. Brain computed tomography scans was normal in 33 (91.7%) cases, while cerebral magnetic resonance imaging (MRI) showed pathologic findings in 62.5% of cases. MRI was the only parameter associated with neurologic sequalae [P = 0.01; OR, 8.1 (95% CI: 1.52-42.84)].

CONCLUSIONS

Pediatric encephalitis is a heterogeneous entity with nonspecific clinical and laboratory findings, with undefined etiologies in most times. MRI can play a primary role, both on a diagnostic and prognostic point-of-view, and its role should be implemented and made more accessible. Further studies are needed to define the exact role and timing of steroids.

Long-Term Survival, Health, Social Functioning, and Education in Patients With an Enterovirus Central Nervous System Infection, Denmark, 1997-2016

BACKGROUND

The long-term clinical course of patients with an enterovirus central nervous system infection (ECI) is poorly understood.

METHODS

We performed a nationwide population-based cohort study of all Danish patients with ECI diagnosed 1997-2016 (n = 1745) and a comparison cohort from the general population individually matched on date of birth and sex (n = 17 450). Outcomes were categorized into mortality and risk of cancer and likely measures of neurological sequelae: neuropsychiatric morbidities, educational landmarks, use of hospital services, employment, receipt of disability pension, income, number of sick leave days, and nursing home residency.

RESULTS

Mortality in the first year was higher among patients with ECI (mortality rate ratio [MRR] = 10.0; 95% confidence interval [CI], 4.17-24.1), but thereafter mortality was not higher (MMR = 0.94; 95% CI, 0.47-1.86). Long-term outcomes for patients with ECI were not inferior to those of the comparison cohort for risk of cancer, epilepsy, mental and behavioral disorders, dementia, depression, school start, school marks, high school education, use of hospital services, employment, receipt of disability pension, income, days of sick leave, or nursing home residency.

CONCLUSIONS

Diagnosis of an ECI had no substantial impact on long-term survival, health, or social/educational functioning.

Neurological and Cognitive Performance After Childhood Encephalitis

Background: Children with encephalitis have increased risk for long-term neurological sequelae. We investigated minor neurological dysfunction (MND) and cognitive performance as a measurement for long-term outcome of encephalitis in childhood. Materials and Methods: Children with encephalitis (n = 98) treated in Turku University Hospital during the years 1995-2016 were retrospectively identified. We included the patients without severe developmental delay before the encephalitis and without recorded neurological disability caused by encephalitis. MND was assessed using the Touwen examination. Age-appropriate Wechsler Intelligence Scale was used to determine the full-scale intelligence quotient (IQ). Residual symptoms in everyday life were evaluated using a questionnaire. Results: Forty-two subjects participated in the study and returned the questionnaire regarding residual symptoms. The median age was 4.3 years at the time of encephalitis, and 11.3 years at the time of the Touwen examination (n = 41) and the cognitive assessment (n = 38). The Touwen examination indicated MND in 29 of 41 participants (71%; simple MND in 16 and complex MND in 13 patients). The median full-scale IQ was lower in participants with MND compared with participants without MND (98 vs. 110, p = 0.02). Participants with IQ < 85 (n = 5) had lower median age at acute encephalitis compared to participants with IQ ≥ 85 (n = 33) (1.8 vs. 5.3 years, p = 0.03). Problems in daily performance were reported in participant with MND (p = 0.2) and low full-scale IQ (p = 0.008). Conclusions: The prevalence of MND was high and it was related to lower cognitive performance after childhood encephalitis. Younger age at acute encephalitis was a risk factor for lower cognitive performance.

Pediatric Simplified Acute Physiology Score II: Establishment of a New, Repeatable Pediatric Mortality Risk Assessment Score

Objectives: In critical care it is crucial to appropriately assess the risk of mortality for each patient. This is especially relevant in pediatrics, with its need for accurate and repeatable scoring. Aim of this study was to evaluate an age-adapted version of the expanded Simplified Acute Physiology Score II; (p-SAPS II), a repeatable, newly-designed scoring system compared to established scores (Pediatric Sequential Organ Failure Assessment Score/pSOFA, Pediatric Logistic Organ Dysfunction Score-2/PELOD-2 and Pediatric Index of Mortality 3/PIM3). Design: This retrospective cohort pilot study included data collected from patients admitted to the Pediatric Intensive Care Unit (PICU) at the Medical University of Vienna between July 2017 through December 2018. Patients: 231 admissions were included, comprising neonates (gestational age of ≥ 37 weeks) and patients up to 18 years of age with a PICU stay longer than 48 h. Main Outcomes: Mortality risk prediction and discrimination between survivors and non-survivors were the main outcomes of this study. The primary statistical methods for evaluating the performance of each score were the area under the receiver operating characteristic curve (AUROC) and goodness-of-fit test. Results: Highest AUROC curve was calculated for p-SAPS II (AUC = 0.86; 95% CI: 0.77-0.96; p < 0.001). This was significantly higher than the AUROCs of PELOD-2/pSOFA but not of PIM3. However, in a logistic regression model including p-SAPS II and PIM3 as covariates, p-SAPS II had a significant effect on the accuracy of prediction (p = 0.003). Nevertheless, according to the goodness-of-fit test for p-SAPS II and PIM3, p-SAPS II overestimated the number of deaths, whereas PIM3 showed acceptable estimations. Repeatability testing showed increasing AUROC values for p-SAPS II throughout the clinical stay (0.96 at day 28) but still no significant difference to PIM 3. The prediction accuracy, although improved over the days and even exceeded PIM 3. Conclusions: The newly-created p-SAPS II performed better than the established PIM3 in terms of discriminating between survivors and non-survivors. Furthermore, p-SAPS II can be assessed repeatably throughout a patient's PICU stay what improves mortality prediction. However, there is still a need to optimize calibration of the score to accurately predict mortality sooner throughout the clinical stay.

Long-Term Outcome of PICU Patients Discharged With New, Functional Status Morbidity

OBJECTIVES

To determine the long-term (> 6 mo) functional status of PICU patients with significant new functional morbidities at hospital discharge.

DESIGN

Longitudinal cohort followed-up using structured chart reviews of electronic health records.

SETTING

Electronic health records of former PICU patients at seven sites.

PATIENTS

Randomly selected patients from the Trichotomous Outcome Prediction in Critical Care study discharged from the hospital with new functional status morbidity who had sufficient electronic health record data to determine functional status.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Long-term functional status was measured with the Functional Status Scale and categorized by comparison to hospital discharge Functional Status Scale. Improvement or new morbidity was based on a change in Functional Status Scale of greater than or equal to 2 in a single domain. Overall, 56% (n = 71) improved, 15% (n = 19) did not change, 9% (n = 11) developed a new morbidity, and 21% (n = 26) died. The shortest median follow-up time from PICU discharge was 1.4 years for those who died and the longest was 4.0 years for those improved. Functional status at baseline (pre-acute illness) was different among the outcome groups with those that improved having the highest frequency of baseline normal status or only mild dysfunction. Of the long-term survivors with improvement, 82% (n = 58) improved to normal status or mild dysfunction, 11% (n = 8) improved to moderate dysfunction, and 7% (n = 5) improved to severe dysfunction. Trauma patients improved and cancer patients died more frequently than other diagnoses. The long-term outcome groups were not associated with hospital discharge functional status.

CONCLUSIONS

A majority of PICU survivors discharged with significant new functional morbidity with follow-up after 6 or more months improved, many to normal status or only mild dysfunction, while 29% died or developed new morbidity. Of the long-term survivors, 70% had significant improvement after a median follow-up time of 4.0 years.

Factors associated with outcome of acute encephalitis in children: a retrospective study of three referral hospitals

BACKGROUND Encephalitis is more frequent in children and has a poor outcome. There was no data on encephalitis in children in Indonesia, so this study was aimed to evaluate clinical presentation and diagnostic examination of children with acute encephalitis, and factors related to outcome. METHODS This was a retrospective study of medical records between 2014 and 2018 in three referral hospitals in Jakarta and Tangerang. Clinical presentation at admission, cerebrospinal fluid analysis, neuroimaging, and electroencephalography (EEG) were documented. Outcome was determined at hospital discharge and classified as poor for severe neurological abnormalities at discharge or died. Logistic regression was used to evaluate associated factors with the outcome. RESULTS A total of 190 children were included and most were age >1 year (71%). Most subjects presented with fever (90%) and seizures (87%). Of those who had seizures, 80% experienced generalized seizures. Focal neurological deficit was seen in 90 patients (47%). EEG was positive in 90% subjects (n = 27/30). Probable cases were found in 51% of all subjects. The mortality was 23%. Focal seizures (odds ratio [OR] = 3.305, 95% confidence interval [CI] = 1.122–9.742) and age >1 year (OR = 3.076, 95% CI = 1.388–6.803) were risk factors for a poor outcome. CONCLUSIONS Acute encephalitis occurred most often in children aged >1 year. Fever and seizures were the most common symptoms. EEG was better than other examinations for confirming diagnosis of encephalitis. Focal seizures and age >1 year were associated with a three-fold increased risk for a poor outcome.

Outcomes measures in children after acute central nervous system infections and malaria

PURPOSE OF REVIEW

Acute central nervous system (CNS) infections in children result in significant mortality and neurologic morbidity worldwide. This article summarizes the recent pediatric literature published on outcomes measures used after acute infectious meningitis, encephalitis, and cerebral malaria, and highlights ongoing research efforts to standardize outcomes measurements. Search terms were geared toward functional, cognitive, behavioral, and other outcome assessments.

RECENT FINDINGS

Recent data suggest that, depending on microbiological cause, there are differences in currently used outcome measures following acute CNS infections. Outcomes assessments include a variety of formal psychological tests (structured interviews and neuropsychological tests of cognitive and motor functioning) and dichotomized or ordinal scales. Standardization of outcome measures, however, is lacking. Global efforts to standardize outcomes that encompass both the child and family are ongoing.

SUMMARY

Centers worldwide can track and measure a variety of cognitive, behavioral, and functional outcomes after acute CNS infections. Standardized documentation and coding of clinically important outcomes is needed. Further research to evaluate effective practices using acute adjunctive and rehabilitation therapies will be aided by outcome measure standardization.

Magnetic resonanse imaging as a prognostic tool in encephalitis in children

We provide the data on the modern use of MRI of different modalities as a prognostic tool in the encephalitis diagnostics in pediatrics. According to the recent scientific knowledge, this implementation is possible, but its efficacy depends on the modality of MRI: structural, functional or MRI with contrast. Structural MRI efficacy in children with encephalitis is dubious and clearly depends on the etiology and phase of the inflammatory process. In the recent years, the implementation of the functional MRI methods (DTI MRS) and MRI with contrast significantly changed the imaging practice; there are some reports that these modalities of MRI are more effective as a prognostic tool in encephalitis than the structural one. Thus, a future research in this field is needed.

Severe acquired brain injury aetiologies, early clinical factors, and rehabilitation outcomes: a retrospective study on pediatric patients in rehabilitation

Objective: Studies on pediatric severe acquired brain injury (sABI) outcomes focused mostly on single etiologies, not clarifying the independent role of clinical factors, and scantly explored inter-dependence between variables. We assessed associations of clinical factors at admission with essential outcomes, controlling for inter-dependence and sABI etiology. Methods: We reviewed the clinical records of 280 patients with traumatic and 292 with non-traumatic sABI, discharged from intensive care to pediatric neurological rehabilitation. We analyzed the distribution of clinical factors based on sABI etiology; conducted a factor analysis of variables; built multivariate models evaluating the associations of variables with death, persistent vegetative states, duration of coma, GOS outcome, length of stay. Results: We described the study sample. Factor analysis of inter-dependence between GCS, time before rehabilitation, dysautonomia, device use, produced the indicators "injury severity" and "neurological dysfunction", independent from sABI etiology, age, sex, and admittance GOS. Multivariate analyzes showed that: coma duration, GOS outcome, and length of stay, which may depend on rehabilitation courses, were directly associated with injury severity, neurological dysfunction, and patients' age; death and persistent vegetative states were also associated with etiology. Conclusion: Future studies should analyze larger cohorts and investigate mechanisms linking specific etiologies and patients' age with outcomes.

Differential In Vitro Infection of Neural Cells by Astroviruses

Encephalitis remains a diagnostic conundrum in humans as over 50% of cases are managed without the identification of an etiology. Astroviruses have been detected from the central nervous system of mammals in association with disease, suggesting that this family of RNA viruses could be responsible for cases of some neurological diseases that are currently without an ascribed etiology. However, there are significant barriers to understanding astrovirus infection as the capacity of these viruses to replicate in nervous system cells in vitro has not been determined. We describe primary and immortalized cultured cells of the nervous system that support infection by astroviruses. These results further corroborate the role of astroviruses in causing neurological diseases and will serve as an essential model to interrogate the neuropathogenesis of astrovirus infection.

Recent advances in unbiased pathogen discovery have implicated astroviruses as pathogens of the central nervous system (CNS) of mammals, including humans. However, the capacity of astroviruses to be cultured in CNS-derived cells in vitro has not been reported to date. Both astrovirus VA1/HMO-C (VA1; mamastrovirus 9) and classic human astrovirus 4 (HAstV4; mamastrovirus 1) have been previously detected from cases of human encephalitis. We tested the ability of primary human neurons, primary human astrocytes, and other immortalized human nervous system cell lines (SK-N-SH, U87 MG, and SW-1088) to support infection and replication of these two astrovirus genotypes. Primary astrocytes and SK-N-SH cells supported the full viral life cycle of VA1 with a >100-fold increase in viral RNA levels during a multistep growth curve, detection of viral capsid, and a >100-fold increase in viral titer. Primary astrocytes were permissive with respect to HAstV4 infection and replication but did not yield infectious virus, suggesting abortive infection. Similarly, abortive infection of VA1 was observed in SW-1088 and U87 MG cells. Elevated expression of the chemokine CXCL10 was detected in VA1-infected primary astrocytes and SK-N-SH cells, suggesting that VA1 infection can induce a proinflammatory host response. These findings establish an in vitro cell culture model that is essential for investigation of the basic biology of astroviruses and their neuropathogenic potential.

A pragmatic cluster randomised controlled trial of a tailored intervention to improve the initial management of suspected encephalitis

OBJECTIVE

To determine whether a tailored multifaceted implementation strategy improves the initial management of patients with suspected encephalitis.

DESIGN

Pragmatic two arm cluster randomised controlled trial.

SETTING

Hospitals within the United Kingdom.

PARTICIPANTS

Twenty-four hospitals nested within 12 postgraduate deaneries. Patients were identified retrospectively by searching discharge, microbiology, radiology and pharmacy records and included if they met clinical criteria or had a recorded suspicion of encephalitis.

INTERVENTION

An implementation strategy designed to overcome barriers to change, comprising local action planning, education and training, feedback on performance, a lumbar puncture pack and a range of optional components.

OUTCOMES

The primary outcome was the proportion of patients with suspected encephalitis undergoing diagnostic lumbar puncture within 12 hours of admission and starting aciclovir treatment within six hours. Secondary outcomes included the proportions of adults and children who had a lumbar puncture, who had appropriate cerebrospinal fluid investigations, and who had appropriate radiological imaging within 24 hours of admission. Data were collected from patient records for 12 months before and 12 months during the intervention period, and analysed blind to allocation.

RESULTS

13 hospitals were randomised to intervention and 11 to control (no intervention), with 266 and 223 patients with suspected encephalitis identified respectively. There was no significant difference in primary outcome between intervention and control hospitals (13.5% and 14.8% respectively, p = 0.619; treatment effect -0.188, 95% confidence interval -0.927 to 0.552), but both had improved compared to pre-intervention (8.5%).

CONCLUSION

The improvement in both intervention and control arms may reflect overall progress in management of encephalitis through wider awareness and education.

TRIAL REGISTRATION

Controlled Trials: ISRCTN06886935.

Long-term outcome of acute central nervous system infection in children

IMPORTANCE

Central nervous system infection is a severe illness in children. Little is known about the long-term outcome in children with central nervous system infection of various etiologies.

OBJECTIVE

The aims of this study were to investigate the long-term outcomes of childhood acute central nervous system infection and to examine possible prognostic factors.

METHODS

Of 172 children who were treated for acute central nervous system infection from January 2009 through December 2009, 139 were eligible for follow-up evaluations. A structured interview was conducted with the parents 3.8-4.7 years after hospital discharge. The global outcome was determined in all patients using the Pediatric Version of the Glasgow Outcome Scale-Extended. Clinical features of the acute episode were retrieved from medical records.

RESULTS

The outcome was favorable in 109 of 139 patients (78%), 38 (27%) were mildly impaired, six (4%) were moderately impaired, 14 (10%) were severely impaired and two (1%) were in a vegetative state. There were eight deaths. The most frequent symptoms were difficulty concentrating (16%), epilepsy (12%), limb paralysis (12%), memory impairment (10%), speech disorders (9%), irritability (9%). Significant risk factors for epilepsy included the presence of recurrent seizures or status epilepticus, the existence of pure spikes in the electroencephalogram, brain parenchyma abnormalities on neuroimaging and herpes simplex virus encephalitis (HSVE). A multivariate analysis identified three factors that were independently associated with poor outcome: coma, brain parenchyma abnormalities on neuroimaging and HSVE.

INTERPRETATION

Most children with acute central nervous system infection experienced a favorable outcome 3.8-4.7 years after discharge from the hospital. Minor to severe disability persists in a high proportion of cases. Coma, brain parenchymal abnormalities on neuroimaging and HSVE may predict poor long-term outcome.

Encephalitis in US Children

Encephalitis is an uncommon but severe disease characterized by neurologic dysfunction with central nervous system inflammation. Children with encephalitis should receive supportive care and empiric therapies for common and treatable causes while prioritizing diagnostic evaluation for common, treatable, and high-risk conditions. Even with an extensive diagnostic workup, an infectious cause is identified in less than half of cases, suggesting a role for postinfectious or noninfectious processes.