Long-term outcome of acute encephalitis of unknown aetiology in adults

Sociodemographic and Clinical Factors Associated With Clinical Outcome in Neuroinfectious Diseases: A Multicenter Retrospective Cohort Study

Objective

To evaluate sociodemographic and clinical factors associated with clinical outcomes in patients hospitalized with neuroinfectious diseases at three tertiary care centers in New York City.

Methods

This retrospective cohort study was conducted at three large urban tertiary care centers between January 1, 2010 and December 31, 2017. Poor clinical outcome was defined as length of hospital stay (LOS) ≥2 weeks and/or discharge to a location other than home. Sociodemographic and clinical factors were obtained from electronic medical records and descriptively analyzed. Multivariate logistic regression analysis investigated relationships between sociodemographic and clinical factors, and outcomes.

Results

Among 205 patients with definitive neuroinfectious diagnoses, older patients were more likely to have a LOS ≥2 weeks (odds ratio [OR]: 1.03; 95% confidence interval [CI]: 1.01-1.05) and less likely to be discharged home (OR: 0.96; 95% CI: 0.94-0.98) than younger patients. Patients with an immunocompromised state were more likely to have a LOS ≥2 weeks (OR: 2.80; 95% CI: 1.17-6.69). Additionally, patients admitted to the intensive care unit (ICU) were more likely to have a LOS ≥2 weeks (OR: 4.65; 95% CI: 2.13-10.16) and less likely to be discharged home (OR: 0.14; 95% CI: 0.06-0.34). There were no statistically significant associations between sex, race, ethnicity, English proficiency, substance use, or poverty index, and clinical outcome.

Conclusions

In this multicenter cohort of hospitalized neuroinfectious diseases, older age, history of immunocompromised state, and admission to the ICU were significantly associated with poor clinical outcome.

Effects of adjunctive Chinese patent medicine on outcome of viral encephalitis in children: A multicenter retrospective study in China

BACKGROUND

Some patients with viral encephalitis in China seek treatment with Chinese patent medicine (CPM) to improve their symptoms, but few studies have focused on the impact of CPM on the prognosis of viral encephalitis (VE). The aim of this multicenter retrospective study was to assess the benefit of adjunctive CPM therapy on the outcome of children with VE in China.

METHODS

This study retrospectively included 834 children with viral encephalitis who were hospitalized at five medical institutions from 2018 to 2021. Univariate and multivariate logistic regression was used to assess the effect of CPM on sequelae in patients with VE. 1:1 propensity score matching was used to exclude the effect of confounding factors. Forest plots were used to observe the effect of CPM on the prognosis of VE in different subgroups.

RESULTS

There were fewer patients with sequelae in the group of patients using CPM regardless of whether they were matched or not. The results of multivariate logistic regression analysis showed that the use of CPM was an independent protective factor for the development of sequelae in VE patients (OR = 0.063, 95 % CI: 0.011-0.350, p = 0.002). Subgroup analyses showed that CPM was a protective factor for the development of sequelae regardless of the presence or absence of coma and comorbidities. In addition, we evaluated other outcome indicators and found shorter duration of illness, fever and headache in children with EV in the CPM group.

CONCLUSION

Adjunctive CPM therapy may significantly reduce sequelae in children with VE, as well as effectively alleviate patients' clinical symptoms. However, more prospective studies and clinical trials are needed to further evaluate its efficacy and safety.

Case report: Fatal Borna virus encephalitis manifesting with basal brain and brainstem symptoms

Background

Since the first report of fatal Borna virus-1 (BoDV-1) encephalitis in 2018, cases gradually increased. There is a lack of diagnostic algorithm, and there is no effective treatment so far.

Case presentation

We report an acute BoDV-1 encephalitis in a 77-year-old female with flu-like onset, rapid progression to word-finding difficulties, personality changes, global disorientation, diffuse cognitive slowness, and gait ataxia and further deterioration with fever, meningism, severe hyponatremia, epileptic seizures, cognitive decline, and focal cortical and cerebellar symptoms/signs. The extensive diagnostic workup (cerebrovascular fluid, serum, and MRI) for (meningo-)encephalitis was negative for known causes. Our empirical common antiviral, antimicrobial, and immunosuppressive treatment efforts failed. The patient fell into coma 5 days after admission, lost all brainstem reflexes on day 18, remained fully dependent on invasive mechanical ventilation thereafter and died on day 42. Brain and spinal cord autopsy confirmed an extensive, diffuse, and severe non-purulent, lymphocytic sclerosing panencephalomyelitis due to BoDV-1, affecting neocortical, subcortical, cerebellar, neurohypophysis, and spinal cord areas. Along with our case, we critically reviewed all reported BoDV-1 encephalitis cases.

Conclusion

The diagnosis of acute BoDV-1 encephalitis is challenging and delayed, while it progresses to fatal. In this study, we list all tried and failed treatments so far for future reference and propose a diagnostic algorithm for prompt suspicion and diagnosis.

The Causes and Long-Term Consequences of Viral Encephalitis

Reports regarding brain inflammation, known as encephalitis, have shown an increasing frequency during the past years. Encephalitis is a relevant concern to public health due to its high morbidity and mortality. Infectious or autoimmune diseases are the most common cause of encephalitis. The clinical symptoms of this pathology can vary depending on the brain zone affected, with mild ones such as fever, headache, confusion, and stiff neck, or severe ones, such as seizures, weakness, hallucinations, and coma, among others. Encephalitis can affect individuals of all ages, but it is frequently observed in pediatric and elderly populations, and the most common causes are viral infections. Several viral agents have been described to induce encephalitis, such as arboviruses, rhabdoviruses, enteroviruses, herpesviruses, retroviruses, orthomyxoviruses, orthopneumovirus, and coronaviruses, among others. Once a neurotropic virus reaches the brain parenchyma, the resident cells such as neurons, astrocytes, and microglia, can be infected, promoting the secretion of pro-inflammatory molecules and the subsequent immune cell infiltration that leads to brain damage. After resolving the viral infection, the local immune response can remain active, contributing to long-term neuropsychiatric disorders, neurocognitive impairment, and degenerative diseases. In this article, we will discuss how viruses can reach the brain, the impact of viral encephalitis on brain function, and we will focus especially on the neurocognitive sequelae reported even after viral clearance.

Lyme neuroborreliosis with encephalitis; a systematic literature review and a Scandinavian cohort study

BACKGROUND

Lyme neuroborreliosis (LNB) presenting with encephalitis is rare and scarcely described.

OBJECTIVES

To describe the available literature on LNB encephalitis, and to characterize this patient-group through a Scandinavian retrospective cohort study.

DATA-SOURCES

Medline, Embase, Scopus, Cochrane library.

STUDY ELIGIBILITY CRITERIA

No discrimination on study-type, time of publication or language.

PARTICIPANTS

Review: all articles with definite LNB and confirmed/possible encephalitis. Cohort: LNB cohorts from Denmark, Sweden and Norway 1990-2019 screened for patients with encephalitis.

METHODS

Review: adhering to PRISMA guidelines, two authors extracted and assessed quality of studies. Cohort: data registered on demography, symptoms, CSF-findings, differentialdiagnostic examinations, treatment, residual symptoms, one-year mortality.

RESULTS

Review: 2330 articles screened on title/abstract, 281 full-texts, yielding 42 articles (case reports/series or cohort studies) including 45 patients from 18 countries spanning 35 years. Altered mental status ranged from personality changes and confusion to unconsciousness. Common focal symptoms were hemiparesis, ataxia and dysarthria, seven patients had seizures. Median time from symptom onset to hospital was 2 weeks (IQR 2-90 days). Of 38 patients with available follow-up after median 12 months (IQR 5-13), 32 had fully or partially recovered, 2 had died. Cohort: 35 patients (median age 67 years,IQR 48-76) were included. The encephalitis prevalence was 3.3%(95%CI 2.2-4.4%) among 1019 screened LNB-patients. Frequent encephalitis symptoms were confusion, personality-changes, aphasia, ataxia. EEGs and neuroimaging showed encephalitis in 93.8% and 20.6%, respectively. Median delay from symptom onset to hospital was 14 days(IQR 7-34), with further 7 days(IQR 3-34) delay until targeted therapy. At follow-up (median 298 days post-treatment(IQR 113-389)), 65.6% had residual symptoms. None had died.

CONCLUSIONS

This study shows that encephalitis is an uncommon, but likely overlooked clinical manifestation of LNB. As the high frequency of residual symptoms may be related to prolonged treatment delay, prompt LNB testing of patients with encephalitis in B.burgdorferi-endemic areas should be considered.

Herpesvirus encephalitis diagnosed by polymerase chain reaction at the National Institute of Neurology of Mexico

The frequency of central nervous system infections due to herpesvirus have been studied in various populations; however, studies in Mexican mestizo patients are scant. This paper documents the frequency of herpesvirus encephalitis in Mexican mestizo patients from the National Institute of Neurology and Neurosurgery (NINN) of Mexico. To study the frequency of herpetic viral encephalitis at the NINN in the period from 2004 to 2009. We reviewed clinical records from patients with clinically suspected encephalitis; polymerase chain reaction assays were done for detection of herpesviruses in cerebrospinal fluid (CSF) samples. The total number of patients studied was 502; in 59 (12%), the diagnosis of herpetic encephalitis was confirmed by PCR-based testing of CSF. Of them, 21 (36%) were positive for herpes simplex virus type 1, 15 (25%) for Epstein-Barr virus, 10 (17%) for varicella zoster virus, 8 (14%) for cytomegalovirus, 3 (5%) for human herpesvirus 6, and 2 (3%) for herpes simplex virus 2. Our results show a varied frequency of viral encephalitis in mestizo patients due to herpesviruses in a tertiary neurological center and point out the importance of modern molecular technology to reach the etiological diagnosis in cases of encephalitis.

Clinical Features, Diagnosis, and Outcome of Encephalitis in French Guiana

The aim of our study was to describe the clinical features, the etiologies, and the factors associated with poor outcome of encephalitis in French Guiana. Our study was retrospective, including all cases of encephalitis hospitalized in the Cayenne General Hospital, from January 2007 to July 2017. Patients were included through the 2013 encephalitis consortium criteria and the outcome was evaluated using the Glasgow outcome scale at 3 months from the diagnosis of encephalitis. We included 108 patients, giving an approximate incidence rate of four cases/100,000 inhabitants/year. The origin of the encephalitis was diagnosed in 81 cases (75%), and 72 of them (66.7%) were from an infectious origin. The most common infectious causes were Cryptococcus sp. (18.5%) independently of the immune status, Toxoplasma gondii (13.9%), and Streptococcus pneumoniae (5.5%). In the follow-up, 48 patients (46.6%) had poor outcome. Independent risk factors associated with poor outcome at 3 months were “coming from inside area of the region” (P = 0.036, odds ratio [OR] = 4.19; CI 95% = 1.09–16.06), need for mechanical ventilation (P = 0.002, OR = 5.92; CI 95% = 1.95–17.95), and age ≥ 65 years (P = 0.049, OR = 3.99; CI 95% = 1.01–15.89). The most identified cause of encephalitis in French Guiana was Cryptococcus. The shape of the local epidemiology highlights the original infectious situation with some local specific pathogens.

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.

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.

30-year trends in admission rates for encephalitis in children in England and effect of improved diagnostics and measles-mumps-rubella vaccination: a population-based observational study

BACKGROUND

Encephalitis is a serious neurological disorder, yet data on admission rates for all-cause childhood encephalitis in England are scarce. We aimed to estimate admission rates for childhood encephalitis in England over 33 years (1979-2011), to describe trends in admission rates, and to observe how these rates have varied with the introduction of vaccines and improved diagnostics.

METHODS

We did a retrospective analysis of hospital admission statistics for encephalitis for individuals aged 0-19 years using national data from the Hospital Inpatient Enquiry (HIPE, 1979-85) and Hospital Episode Statistics (HES, 1990-2011). We analysed annual age-specific and age-standardised admission rates in single calendar years and admission rate trends for specified aetiologies in relation to introduction of PCR testing and measles-mumps-rubella (MMR) vaccination. We compared admission rates between the two International Classification of Diseases (ICD) periods, ICD9 (1979-94) and ICD10 (1995-2011).

FINDINGS

We found 16 571 encephalitis hospital admissions in the period 1979-2011, with a mean hospital admission rate of 5·97 per 100 000 per year (95% CI 5·52-6·41). Hospital admission rates declined from 1979 to 1994 (ICD9; annual percentage change [APC] -3·30%; 95% CI -2·88 to -3·66; p<0·0001) and increased between 1995 and 2011 (ICD10; APC 3·30%; 2·75-3·85; p<0·0001). Admissions for measles decreased by 97% (from 0·32 to 0·009) and admissions for mumps encephalitis decreased by 98% (from 0·60 to 0·01) after the introduction of the two-dose MMR vaccine. Hospital admission rates for encephalitis of unknown aetiology have increased by 37% since the introduction of PCR testing.

INTERPRETATION

Hospital admission rates for all-cause childhood encephalitis in England are increasing. Admissions for measles and mumps encephalitis have decreased substantially. The numbers of encephalitis admissions without a specific diagnosis are increasing despite availability of PCR testing, indicating the need for strategies to improve aetiological diagnosis in children with encephalitis.

FUNDING

None.

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

BACKGROUND

Factors associated with poor outcomes of children with encephalitis are not well known. We sought to determine whether electroencephalography (EEG) findings, magnetic resonance imaging (MRI) abnormalities, or the presence of seizures at presentation were associated with poor outcomes.

METHODS

A retrospective review of patients aged 0 to 21 years who met criteria for a diagnosis of encephalitis admitted between 2000 and 2010 was conducted. Parents of eligible children were contacted and completed 2 questionnaires that assessed current physical and emotional quality of life and neurological deficits at least 1 year after discharge.

RESULTS

During the study period, we identified 142 patients with an International Classification of Diseases 9th Revision diagnosis of meningitis, meningoencephalitis, or encephalitis. Of these patients, 114 met criteria for a diagnosis of encephalitis, and 76 of these patients (representing 77 hospitalizations) had complete data available. Forty-nine (64%) patients were available for follow-up. Patients admitted to the intensive care unit were more likely to have abnormal EEG results (P = .001). The presence of seizures on admission was associated with ongoing seizure disorder at follow-up. One or more years after hospitalization, 78% of the patients had persistent symptoms, including 35% with seizures. Four (5%) of the patients died. Abnormal MRI findings and the number of abnormal findings on initial presentation were associated with lower quality-of-life scores.

CONCLUSIONS

Encephalitis leads to significant morbidity and death, and incomplete recovery is achieved in the majority of hospitalized patients. Abnormal EEG results were found more frequently in critically ill children, patients with abnormal MRI results had lower quality-of-life scores on follow-up, and the presence of seizures on admission was associated with ongoing seizure disorder and lower physical quality-of-life scores.

First reported cases of anti-NMDA receptor encephalitis in Vietnamese adolescents and adults

Introduction

Anti-NMDA receptor encephalitis is increasingly recognised as an important differential diagnosis in patients with encephalitis of unknown aetiology. We report the first case series of patients diagnosed in Vietnam.

Methods

Samples of CSF from patients with presumed encephalitis but negative microbiological investigations, who exhibited dyskinesia, autonomic instability or psychosis were tested for antibodies against the NR1 subunit of the glutamate (type-NMDA) receptor using an indirect immunofluorescence assay.

Results

Of 99 patients admitted with all-cause encephalitis over an 18 month period, 9.1% (n = 9 patients, 5 female, median age 28 years) had confirmed NMDAR encephalitis. All patients were admitted from one mental health hospital, and the incidence may therefore be an underestimate. Common features included reduction in speech (n = 9), catatonia (n = 9), convulsions (n = 7), dyskinesia (n = 9), rigidity (n = 9) and autonomic dysfunction (n = 7). Aside from a modest lymphocytic pleocytosis, routine CSF analysis was usually normal. No female patient had ovarian teratoma detected by abdominal ultrasound. Most patients were treated with high dose corticosteroids, and one patient received intravenous immunoglobulin. The median duration of hospitalization was 75 days and no patient died during admission.

Conclusions

Anti-NMDA receptor encephalitis is an important differential diagnosis to consider for patients presenting with acute onset psychiatric symptoms, who develop ensuing seizures, movement or autonomic disorder in Vietnam. A stronger evidence base for management and access to second line immunotherapy agents may help to reduce morbidity from this disease.

•

Anti-NMDA encephalitis is an important differential for unexplained encephalitis.

•

For the first time we have confirmed the diagnosis in adolescents and adults in Vietnam.

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Psychiatric symptoms are followed by movement/autonomic disorder and convulsions.

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Treatment is usually with high dose corticosteroids.

•

A robust evidence base is required to support clinical management algorithms.

Infectious encephalitis: utility of a rational approach to aetiological diagnosis in daily clinical practice

In this study we attempt to assess the utility of a simplified step-wise diagnostic algorithm to determinate the aetiology of encephalitis in daily clinical practice and to describe the main causes in our setting. This was a prospective cohort study of all consecutive cases of encephalitis in adult patients diagnosed between January 2010 and March 2015 at the University Hospital Vall d'Hebron in Barcelona, Spain. The aetiological study was carried out following the proposed step-wise algorithm. The proportion of aetiological diagnoses achieved in each step was analysed. Data from 97 patients with encephalitis were assessed. Following a simplified step-wise algorithm, a definite diagnosis was made in the first step in 53 patients (55 %) and in 12 additional cases (12 %) in the second step. Overall, a definite or probable aetiological diagnosis was achieved in 78 % of the cases. Herpes virus, L. monocytogenes and M. tuberculosis were the leading causative agents demonstrated, whereas less frequent aetiologies were observed, mainly in immunosuppressed patients. The overall related mortality was 13.4 %. According to our experience, the leading and treatable causes of encephalitis can be identified in a first diagnostic step with limited microbiological studies. L. monocytogenes treatment should be considered on arrival in some patients. Additional diagnostic effort should be made in immunosuppressed patients.

Encephalitis, Ontario, Canada, 2002-2013

The epidemiology of encephalitis in Ontario is remarkably similar to that in England.

Encephalitis, a brain inflammation leading to severe illness and often death, is caused by >100 pathogens. To assess the incidence and trends of encephalitis in Ontario, Canada, we obtained data on 6,463 Ontario encephalitis hospitalizations from the hospital Discharge Abstract Database for April 2002–December 2013 and analyzed these data using multiple negative binomial regression. The estimated crude incidence of all-cause encephalitis in Ontario was ≈4.3 cases/100,000 persons/year. Incidence rates for infants <1 year of age and adults >65 years were 3.9 and 3.0 times that of adults 20–44 years of age, respectively. Incidence peaks during August–September in 2002 and 2012 resulted primarily from encephalitis of unknown cause and viral encephalitis. Encephalitis occurred more frequently in older age groups and less frequently in women in Ontario when compared to England, but despite differences in population, vector-borne diseases, climate, and geography, the epidemiology was overall remarkably similar in the two regions.

Clinical characteristics and outcome of clinically diagnosed viral encephalitis in southwest China

Patients with viral encephalitis have a high incidence of morbidity and mortality. We analyze the clinical characteristics and outcome of patients with clinically diagnosed viral encephalitis to investigate possible predictors of prognosis. We retrospectively evaluated 1107 patients diagnosed with viral encephalitis in southwest China from 2009 to 2012 by evaluating their outcomes using the Glasgow Outcome Scale. We compared patient outcome at hospital discharge with long-term follow-up visits, and evaluated the prognostic indicators of the outcome. At hospital discharge, 375 (33.9 %) of the 1107 patients who survived made a full recovery, while 399 (36.0 %), 160 (14.5 %), and 145 (13.1 %) had mild, moderate or severe neurologic sequelae, respectively. Twenty-eight (2.5 %) of the patients died prior to discharge from the hospital. Of the 1027 patients who had follow-up assessments, 658 (64.1 %) made a full recovery, while 213 (20.7 %), 103 (10.0 %), and 19 (1.8 %) had mild, moderate or severe neurologic sequelae, respectively. Six (0.6 %) of the patients died after discharge from the hospital. Use of mechanical ventilation, lower Glasgow coma score, and concurrent seizures are predictors for a poor outcome in patients both at hospital discharge and at long-term follow-up visits.

Neurofilament heavy chain as a marker of neuroaxonal pathology and prognosis in acute encephalitis

BACKGROUND AND PURPOSE

The neurological outcome of acute encephalitis can be devastating and early prognosis remains difficult. Biomarkers that quantify the extent of early brain injury are needed to improve the prognostic accuracy and aid patient management. Our objective was to assess whether cerebrospinal fluid (CSF) protein biomarkers of neuroaxonal and glial cell injury are elevated in distinct forms of acute encephalitis and predictive of poor outcome.

METHODS

This was a prospective study of patients presenting with acute encephalitis to three teaching hospitals in London, UK. Levels of neurofilament heavy chain (NfH, SMI35) and S100B were quantified in CSF using enzyme-linked immunosorbent assay. The outcome was assessed by the Glasgow Outcome Scale (GOS).

RESULTS

Fifty-six patients with acute encephalitis were recruited and classified into the following diagnostic categories: infectious (n = 20), inflammatory (n = 14) and unknown etiology (n = 22). Pathological levels of NfH and S100B were observed in 24/56 (43%) and 54/56 (96%), respectively. Patients with infectious encephalitis had significantly higher NfH levels compared with the other two groups (P < 0.05). A poor outcome (GOS < 5) was associated with significantly higher CSF NfH levels within samples taken 2 weeks after symptom onset.

CONCLUSIONS

This study suggests that longitudinal CSF NfH levels are of superior prognostic value compared with CSF S100B levels. Prolonged release of NfH, a marker of neuroaxonal damage, was associated with poor outcome. Potentially there is a window of opportunity for future neuroprotective treatment strategies in encephalitis.

Epidemiology, outcomes and predictors of recovery in childhood encephalitis: a hospital-based study

BACKGROUND

Pediatric encephalitis is a devastating diagnosis with little guidance regarding prognostic indicators early in the hospitalization.

METHODS

This is a retrospective cohort study of patients with encephalitis referred to the California Encephalitis Project from Children's Hospital & Research Center Oakland from 1998 to 2010. Demographic, clinical, laboratory and neuroimaging data were collected by California Encephalitis Project and chart review. Outcomes were classified into "recovery" or "incomplete recovery" and evaluated at discharge and other times (7-10 days postadmission, 3 and 12 months postdischarge). Using logistic regression, predictors associated with recovery were identified.

RESULTS

Of 190 patients with outcomes available at discharge, 128 patients (67.4%) recovered, whereas 62 (32.6%) had an incomplete recovery, including 13 deaths (6.8%). Variables predictive of outcomes at discharge in the bivariate and multivariable analyses included Asian/Pacific Islander race, neuroimaging results and Glasgow Coma Score. Asian/Pacific Islander patients were less likely to recover than patients of other races (adjusted odds ratio = 0.43, P = 0.046). Patients with normal neuroimaging studies were more likely to recover than patients with abnormal neuroimaging (adjusted odds ratio = 2.54, P = 0.008). Patients with Glasgow Coma Score ≥7 were more likely to recover than patients with Glasgow Coma Score <7 (adjusted odds ratio = 5.82, P < 0.001). In a multivariable analysis, similar statistically significant findings were noted at all other analyzed times. Results were similar using a different population for validation, however, due to the small number of Asian/Pacific Islander patients; this finding could not be validated.

CONCLUSIONS

This study is unique in identification of race/ethnicity as an independent predictor of pediatric encephalitis outcomes. Additional variables may be useful ancillary tools in determining prognosis.

Brainstem encephalitis: etiologies, treatment, and predictors of outcome

Brainstem encephalitis (BE) is an uncommon condition. We sought to characterize clinical presentations, etiologies, response to treatment, and predictors of outcome. We performed a retrospective review of non-HIV infected patients diagnosed with BE at Johns Hopkins Hospital (January 1997-April 2010). We characterized clinical and paraclinical features, and used regression models to assess associations with poor outcome. BE was diagnosed in 81 patients. An etiology was identified in 58 of 81 (71.6%) of cases, most of which were confirmed or probable inflammatory/autoimmune conditions. Of the remaining 23 cases in which a specific diagnosis remained undefined, clinical presentation, CSF, neuroimaging studies, and outcomes were similar to the inflammatory/autoimmune group. Brain biopsy identified a specific diagnosis in 7 of 14 patients (50%). Fifteen patients (18.5%) either died or had a poor outcome. In multivariate logistic regression models, a higher CSF protein (per 5 mg/dl, OR = 1.11, 95% CI: 1.03-1.20), a higher CSF glucose (per 5 mg/dl, OR = 1.36, 95% CI: 1.09-1.70), and higher serum glucose (per 5 mg/dl, OR = 1.27, 95% CI: 1.06-1.52) were independently associated with increased odds of poor outcome. Inflammatory and non-infectious conditions accounted for most cases of BE. Higher CSF protein and glucose were independently associated with poor outcome. In immunocompetent patients with BE of undefined etiology despite extensive investigation, a trial of immunosuppressive treatment may be warranted, though deterioration clinically or on magnetic resonance imaging should prompt a brain biopsy.