Epidemiology of Meningitis and Encephalitis in Infants and Children in the United States, 2011-2014

Epidemiology of Enterovirus Genotypes in Association with Human Diseases

Enteroviruses (EVs) are well-known causes of a wide range of infectious diseases in infants and young children, ranging from mild illnesses to severe conditions, depending on the virus genotypes and the host's immunity. Recent advances in molecular surveillance and genotyping tools have identified over 116 different human EV genotypes from various types of clinical samples. However, the current knowledge about most of these genotypes, except for those of well-known genotypes like EV-A71 and EV-D68, is still limited due to a lack of comprehensive EV surveillance systems. This limited information makes it difficult to understand the true burden of EV-related diseases globally. Furthermore, the specific EV genotype associated with diseases varies according to country, population group, and study period. The same genotype can exhibit different epidemiological features in different areas. By integrating the data from established EV surveillance systems in the USA, Europe, Japan, and China, in combination with other EV infection studies, we can elaborate a better understanding of the distribution of prevalent EV genotypes and the diseases associated with EV. This review analyzed the data from various EV surveillance databases and explored the EV seroprevalence and the association of specific EV genotypes with human diseases.

Enteroviruses: epidemic potential, challenges and opportunities with vaccines

Enteroviruses (EVs) are the most prevalent viruses in humans. EVs can cause a range of acute symptoms, from mild common colds to severe systemic infections such as meningitis, myocarditis, and flaccid paralysis. They can also lead to chronic diseases such as cardiomyopathy. Although more than 280 human EV serotypes exist, only four serotypes have licenced vaccines. No antiviral drugs are available to treat EV infections, and global surveillance of EVs has not been effectively coordinated. Therefore, poliovirus still circulates, and there have been alarming epidemics of non-polio enteroviruses. Thus, there is a pressing need for coordinated preparedness efforts against EVs.This review provides a perspective on recent enterovirus outbreaks and global poliovirus eradication efforts with continuous vaccine development initiatives. It also provides insights into the challenges and opportunities in EV vaccine development. Given that traditional whole-virus vaccine technologies are not suitable for many clinically relevant EVs and considering the ongoing risk of enterovirus outbreaks and the potential for new emerging pathogenic strains, the need for new effective and adaptable enterovirus vaccines is emphasized.This review also explores the difficulties in translating promising vaccine candidates for clinical use and summarizes information from published literature and clinical trial databases focusing on existing enterovirus vaccines, ongoing clinical trials, the obstacles faced in vaccine development as well as the emergence of new vaccine technologies. Overall, this review contributes to the understanding of enterovirus vaccines, their role in public health, and their significance as a tool for future preparedness.

Meningitis in Children: Still a Can't-Miss Diagnosis

Although vaccination and antimicrobial treatment have significantly impacted the frequency and outcomes of meningitis in children, meningitis remains a critical can't-miss diagnosis for children, where early recognition and appropriate treatment can improve survival and neurologic outcomes. Signs and symptoms may be nonspecific, particularly in infants, and require a high index of suspicion to recognize potential meningitis and obtain the cerebrospinal fluid studies necessary for diagnosis. Understanding the pathogens associated with each age group and specific risk factors informs optimal empirical antimicrobial therapy. Early treatment and developmental support can significantly improve the survival rates and lifelong neurodevelopment of children with central nervous system infections.

Atypical Presentation Resembling Acute Leukoencephalopathy With Restricted Diffusion in Staphylococcus aureus Meningoencephalitis

Meningoencephalitis refers to inflammation of the brain and meninges. It can be caused by various organisms, such as Neisseria meningitidis, Streptococcus pneumoniae, and so on. Staphylococcus aureus causing meningoencephalitis is relatively rare. It is mainly encountered in patients who have undergone surgeries in the past. Acute leukoencephalopathy with restricted diffusion (ALERD) is a type of encephalopathy that can involve both white and grey matter of the brain, and it has a characteristic "bright tree appearance" on MRI. It can be because of various infectious etiologies or caused by various toxins. Neurological sequelae are observed in about two out of three cases. Here, we describe a case of S. aureus meningoencephalitis with ALERD, which has been seldom reported. More awareness about this is required among primary care physicians for timely diagnosis and management to prevent any complications.

Early life parechovirus infection neuropsychological outcomes at 8 years: a cohort study

Human parechovirus (HPeV) is a leading cause of Central Nervous System (CNS) infection in infancy. Despite this, little is known regarding the long-term neuropsychological impacts from HPeV infection. The aim of the present study was to explore the long-term neuropsychological impacts eight-year post-HPeV infection contracted during infancy. This study also aimed to investigate the differential impacts of HPeV itself compared to the effects of secondary meningitis (n = 23) or encephalitis (n = 3) associated with HPeV infection. Thirty-nine HPeV children participated in the study. Children completed performance-based measures of neuropsychological and language functioning (the Wechsler Abbreviated Scale of Intelligence, the Clinical Evaluation of Language Fundamentals - Fourth Edition, and the Test of Everyday Attention for Children). Parents completed questionnaire-based measures of emotional, behavioral, and pragmatic language functioning (the Behaviour Rating Inventory of Executive Functioning, the Child Behavior Checklist, and the Social Communication Questionnaire). Results revealed that, overall, children with HPeV were significantly more impaired on measures of selective, sustained, and divided attention compared to normative test populations. The current study incidentally found at least double the prevalence of Attention-Deficit/Hyperactivity Disorder (ADHD) in the HPeV sample than what is typical in the normal population, suggesting that HPeV infection during infancy may be a risk factor for the later development of ADHD. Additionally, the presence of secondary meningitis or encephalitis did not relate to poorer neuropsychological outcomes in the current sample. The findings of this study have important implications regarding clinical management for children following HPeV infection in infancy.

The Clinical and Genetic Characteristics of Streptococcus agalactiae Meningitis in Neonates

Streptococcus agalactiae (Group B Streptococcus, GBS) is an important pathogen of bacterial meningitis in neonates. We aimed to investigate the clinical and genetic characteristics of neonatal GBS meningitis. All neonates with GBS meningitis at a tertiary level medical center in Taiwan between 2003 and 2020 were analyzed. Capsule serotyping, multilocus sequence typing, antimicrobial resistance, and whole-genome sequencing (WGS) were performed on the GBS isolates. We identified 48 neonates with GBS meningitis and 140 neonates with GBS sepsis. Neonates with GBS meningitis had significantly more severe clinical symptoms; thirty-seven neonates (77.8%) had neurological complications; seven (14.6%) neonates died; and 17 (41.5%) survivors had neurological sequelae at discharge. The most common serotypes that caused meningitis in neonates were type III (68.8%), Ia (20.8%), and Ib (8.3%). Sequence type (ST) is highly correlated with serotypes, and ST17/III GBS accounted for more than half of GBS meningitis cases (56.3%, n = 27), followed by ST19/Ia, ST23/Ia, and ST12/Ib. All GBS isolates were sensitive to ampicillin, but a high resistance rates of 72.3% and 70.7% to erythromycin and clindamycin, respectively, were noted in the cohort. The virulence and pilus genes varied greatly between different GBS serotypes. WGS analyses showed that the presence of PezT; BspC; and ICESag37 was likely associated with the occurrence of meningitis and was documented in 60.4%, 77.1%, and 52.1% of the GBS isolates that caused neonatal meningitis. We concluded that GBS meningitis can cause serious morbidity in neonates. Further experimental models are warranted to investigate the clinical and genetic relevance of GBS meningitis. Specific GBS strains that likely cause meningitis requires further investigation and clinical attention.

Seasonal Trends in the Prevalence and Incidence of Viral Encephalitis in Korea (2015-2019)

Viral infections are a common cause of encephalitis. This study investigated the relationship between the incidence of encephalitis and that of respiratory and enteric viral infections in all age groups from 2015 to 2019, using the Health Insurance Review and Assessment (HIRA) Open Access Big Data Platform. We identified monthly incidence patterns and seasonal trends using the autoregressive integrated moving average (ARIMA). The Granger causality test was used to analyze correlations between encephalitis incidence and the positive detection rate (PDR) at 1-month intervals. A total of 42,775 patients were diagnosed with encephalitis during the study period. The incidence of encephalitis was highest in the winter (26.8%). The PDRs for respiratory syncytial virus (HRSV) and coronavirus (HCoV) were associated with the trend in encephalitis diagnosis in all age groups, with a 1-month lag period. In addition, an association with norovirus was observed in patients aged over 20 years, and with influenza virus (IFV) in patients aged over 60 years. This study found that HRSV, HCoV, IFV, and norovirus tended to precede encephalitis by 1 month. Further research is required to confirm the association between these viruses and encephalitis.

Clonal Complex 12 Serotype Ib Streptococcus agalactiae Strain Causing Complicated Sepsis in Neonates: Clinical Features and Genetic Characteristics

Streptococcus agalactiae (group B Streptococcus [GBS]) is well known to cause serious diseases in infants. A serotype Ib GBS strain has recently emerged and become prevalent in Southeast Asia. We aimed to investigate the clinical and genetic characteristics of this strain. All neonates with invasive GBS diseases from a tertiary-level medical center in Taiwan between 2003 and 2020 were analyzed. The capsule serotyping, multilocus sequence typing, and antimicrobial resistance analyses were performed on all the invasive GBS isolates, and whole-genome sequencing (WGS) was performed specifically on the type Ib GBS strain. A total of 188 neonates with invasive GBS disease during the study period were identified. The type Ib GBS strain accounted for 7.4% (n = 14) of neonatal GBS invasive diseases. Almost all type Ib GBS isolates belonged to sequence type 12 (13/14, 92.9%) and clonal complex 12. Neonates with type Ib GBS disease had a significantly higher rate of complicated sepsis (10/14, 71.4%; P < 0.05) and sepsis-attributable mortality (6/14, 42.9%; P < 0.05). Additionally, type Ib GBS isolates had significantly higher rates of resistance to erythromycin and clindamycin (both 100%; P < 0.05) than other GBS serotypes. WGS revealed the presence of an ~75-kb integrative and conjugative element, ICESag37, comprising multiple antibiotic resistance and virulence genes, and PI-1 plus PI-2a were noted in all type Ib serotype 12 (ST12) GBS isolates; these isolates may be responsible for its high invasiveness and antimicrobial resistance rates. The genomic characteristics of the type Ib clonal complex 12 (CC12) GBS strain may account for the high illness severity associated with this strain and its antibiotic resistance. Continuous monitoring and advanced strategies to control the spread of type Ib CC12 GBS should be considered. IMPORTANCE A type Ib ST12 GBS strain is not a common isolate in neonatal invasive diseases and has been ignored for a long time. However, the recent literature and our data showed that such a GBS strain is associated with a significantly higher risk of severe sepsis, higher illness severity, and a significantly higher rate of sepsis-attributable mortality. This study found a novel gene cluster, including the presence of ICESag37 and specific pilus genes, carrying multiple antimicrobial resistance and virulence genes, which may be responsible for the clinical characteristics. Because of the higher mortality and severity of illness, we concluded that continuous monitoring of the type Ib ST12 GBS strain is warranted in the future.

Diagnosis of Neurological Infections in Pediatric Patients from Cell-Free DNA Specimens by Using Metagenomic Next-Generation Sequencing

Central nervous system (CNS) infections can cause significant morbidity and mortality, especially in children. Rapid and accurate pathogenic detection in suspected CNS infections is essential for disease control at the early stage of infection. To evaluate the performance of metagenomic next-generation sequencing (mNGS) of cell-free DNA (cfDNA) in cerebrospinal fluid (CSF) in pediatric patients, we retrospectively analyzed the efficiency of cfDNA mNGS in children with CNS infections (n = 257) or noninfectious neurological disorders (n = 81). The CSF samples of 124 random subjects were used to evaluate the accuracy between mNGS of cfDNA and whole-cell DNA (wcDNA). In total, cfDNA mNGS detected a wide range of microbes with a detection rate of 71.0%, and the sensitivity and total coincidence rate with clinical diagnosis reached 68.9% and 67.5%, respectively. Compared with wcDNA mNGS, cfDNA mNGS had a higher efficacy in detecting viruses (66 versus 13) and Mycobacterium (7 versus 1), with significantly higher reads per million. The dominant causative pathogens were bacteria and viruses in CNS infections, but these presented with different pathogen spectra in different age categories. The best timing for the mNGS test ranged from 1 to 6 days after the start of anti-infection therapy, and the earlier mNGS started, the better was identification of bacterial CNS infections. This study emphasized that cfDNA mNGS had overall superiority to conventional methods on causative pathogen detection in pediatric CNS infections, and it was even better than wcDNA mNGS. Furthermore, research needs to be better validated in large-scale clinical trials to improve the clinical applications of cfDNA mNGS. IMPORTANCE Our study emphasized that cfDNA mNGS had overall superiority to conventional methods on causative pathogen detection in CNS-infected children, and it was even better than wcDNA mNGS. cfDNA mNGS detected a wide range of pathogens with a high total coincidence rate (67.5%) against clinical diagnosis. The best timing for cfDNA mNGS detection ranged from 1 to 6 days, rather than 0 days, after the start of empirical anti-infection therapy. The earlier mNGS started, the better the identifications of bacterial CNS infections. To the best of our knowledge, this research is the first report evaluating the clinical utility of mNGS with different methods (cfDNA versus wcDNA) of extracting DNA from CSF specimens in diagnosing pediatric CNS infections. Meanwhile, this is the largest cohort study that has evaluated the performance of mNGS using cfDNA from CSF specimens in pediatric patients with CNS infections.

Epidemiological characteristics and climatic variability of viral meningitis in Kazakhstan, 2014-2019

Background

The comprehensive epidemiology and impact of climate on viral meningitis (VM) in Kazakhstan are unknown. We aimed to study the incidence, in-hospital mortality and influence of climatic indicators on VM from 2014 to 2019.

Methods

Nationwide electronic healthcare records were used to explore this study. ICD-10 codes of VM, demographics, and hospital outcomes were evaluated using descriptive statistics and survival analysis.

Results

During the 2014-2019 period, 10,251 patients with VM were admitted to the hospital. 51.35% of them were children, 57.85% were males, and 85.9% were from the urban population. Enteroviral meningitis was the main cause of VM in children. The incidence rate was 13 and 18 cases per 100,000 population in 2014 and 2019, respectively. Case fatality rate was higher in 2015 (2.3%) and 2017 (2.0%). The regression model showed 1°C increment in the daily average temperature might be associated with a 1.05-fold (95% CI 1.047-1.051) increase in the daily rate of VM cases, 1hPa increment in the average air pressure and 1% increment in the daily average humidity might contribute to a decrease in the daily rate of VM cases with IRRs of 0.997 (95% CI 0.995-0.998) and 0.982 (95% CI 0.981-0.983), respectively. In-hospital mortality was 35% higher in males compared to females. Patients residing in rural locations had a 2-fold higher risk of in-hospital death, compared to city residents. Elderly patients had a 14-fold higher risk of in-hospital mortality, compared to younger patients.

Conclusion

This is the first study in Kazakhstan investigating the epidemiology and impact of climate on VM using nationwide healthcare data. There was a tendency to decrease the incidence with outbreaks every 5 years, and mortality rates were higher for Russians and other ethnicities compared to Kazakhs, for males compared to females, for elder patients compared to younger patients, and for patients living in rural areas compared to city residents. The climatic parameters and the days of delay indicated a moderate interaction with the VM cases.

Metagenomic next-generation sequencing and proteomics analysis in pediatric viral encephalitis and meningitis

Introduction

Early and accurate identification of pathogens is essential for improved outcomes in patients with viral encephalitis (VE) and/or viral meningitis (VM).

Methods

In our research, Metagenomic next-generation sequencing (mNGS) which can identify viral pathogens unbiasedly was performed on RNA and DNA to identify potential pathogens in cerebrospinal fluid (CSF) samples from 50 pediatric patients with suspected VEs and/or VMs. Then we performed proteomics analysis on the 14 HEV-positive CSF samples and another 12 CSF samples from health controls (HCs). A supervised partial least squaresdiscriminant analysis (PLS-DA) and orthogonal PLS-DA (O-PLS-DA) model was performed using proteomics data.

Results

Ten viruses in 48% patients were identified and the most common pathogen was human enterovirus (HEV) Echo18. 11 proteins overlapping between the top 20 DEPs in terms of P value and FC and the top 20 proteins in PLS-DA VIP lists were acquired.

Discussion

Our result showed mNGS has certain advantages on pathogens identification in VE and VM and our research established a foundation to identify diagnosis biomarker candidates of HEV-positive meningitis based on MS-based proteomics analysis, which could also contribute toward investigating the HEV-specific host response patterns.

Progress and Challenges in Bacterial Meningitis: A Review

IMPORTANCE

Bacterial meningitis is a worldwide health problem, with incidence rates ranging from approximately 0.9 per 100 000 individuals per year in high-income countries to 80 per 100 000 individuals per year in low-income countries. In low-income countries, bacterial meningitis has a mortality rate of up to 54%. Up to 24% of those who survive develop chronic neurological sequelae, such as hearing loss or focal neurological deficits.

OBSERVATIONS

Streptococcus pneumoniae causes about 72% and Neisseria meningitidis causes about 11% of cases of bacterial meningitis in people older than 16 years. Escherichia coli and Streptococcus agalactiae cause about 35% of cases of early-onset neonatal meningitis. In adults, risk factors for bacterial meningitis include older age and immunosuppressive conditions. The most common symptoms are headache (84%), fever (74%), stiff neck (74%), altered mental status (median [IQR] Glasgow Coma Scale score of 11 [9-14] on a scale ranging from 3-15), and nausea (62%). Brain imaging should be performed before lumbar puncture if patients present with altered mental status, focal neurological deficits, papilledema, or history of immunocompromising conditions or central nervous system disease. Bacterial meningitis should be suspected if any of the following are present on admission: serum leukocytes greater than 10.0 ×109/L, cerebrospinal fluid (CSF) leukocytes greater than 2000/μL, CSF granulocytes greater than 1180/μL, CSF protein greater than 2.2 g/L, CSF glucose less than 34.23 mg/dL, or fever. A positive Gram stain result for bacteria is diagnostic, but the sensitivity of a positive Gram stain result for bacterial meningitis ranges from 50% to 90%. In countries in which the prevalence of ceftriaxone-resistant Streptococcus pneumoniae exceeds 1%, vancomycin and ceftriaxone are the empirical antibiotics of choice, with the addition of ampicillin in neonates, older patients, and immunocompromised patients. Adjunctive dexamethasone should be used in patients with bacterial meningitis but stopped if Listeria monocytogenes is confirmed.

CONCLUSIONS AND RELEVANCE

Bacterial meningitis affects approximately 0.9 per 100 000 individuals to 80 per 100 000 individuals per year and has a mortality rate as high as 54%. First-line therapy is prompt empirical intravenous antibiotic therapy and adjunctive dexamethasone.

FilmArray® Meningoencephalitis panel in the diagnosis of central nervous system infections: stewardship and cost analysis in a paediatric hospital in Chile

BACKGROUND

Central nervous system (CNS) infection has been an ongoing concern in paediatrics. The FilmArray® Meningoencephalitis (FAME) panel has greater sensitivity in identifying the aetiology of CNS infections. This study's objective was to compare the aetiological identification and hospitalization costs among patients with suspected CNS infection before and after the use of FAME.

METHODS

An analytical observational study was carried out using a retrospective cohort for the pre-intervention (pre-FAME use) period and a prospective cohort for the post-intervention (post-FAME use) period in children with suspected CNS infection.

RESULTS

A total of 409 CSF samples were analysed, 297 pre-intervention and 112 post-intervention. In the pre-intervention period, a total of 85.5% of patients required hospitalization, and in the post-intervention period 92.7% required hospitalization (p < 0.05). Median of ICU days was significantly lower in the post-intervention period than it was in the pre-intervention period. The overall positivity was 9.4 and 26.8%, respectively (p < 0.001). At ages 6 months and below, we found an increase in overall positivity from 2.6 to 28.1%, along with an increased detection of viral agents, S. agalactiae, S. pneumoniae, and N. meningitidis. The use of this diagnostic technology saved between $2916 and $12,240 USD in the cost of ICU bed-days. FAME use provided the opportunity for more accurate aetiological diagnosis of the infections and thus the provision of adequate appropriate treatment.

CONCLUSIONS

The cost/benefit ratio between FAME cost and ICU bed-day cost savings is favourable. Implementation of FAME in Chilean public hospitals saves public resources and improves the accuracy of aetiological diagnosis.

Comparison and development of a metagenomic next-generation sequencing protocol for combined detection of DNA and RNA pathogens in cerebrospinal fluid

BACKGROUND

The purpose of this study was to evaluate different pretreatment, extraction, amplification, and library generation methods for metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF) and to develop an efficient procedure for the simultaneous detection of DNA and RNA pathogens.

METHODS

We generated thirteen mock CSF samples with four representative pathogens of encephalitis. Each sample was subjected to ten different methods by varying sample pretreatment/nucleic acid extraction (microbial DNA, total DNA, total NA, total RNA, Whole Transcriptome Amplification (WTA)) and library generation (Illumina or NEB). Negative extraction controls (NECs) were used for each method variation.

RESULTS

We found that the quality of mNGS sequencing reads was higher from the NEB kit for library generation. Microbial DNA and total RNA increased microbial deposition by depleting the host DNA. Methods total NA and total RNA can detect gram-positive, gram-negative, RNA and DNA pathogens. We applied mNGS, including total NA and NEB library generation, to CSF samples from five patients diagnosed with infectious encephalitis and correctly determined all pathogens identified in clinical etiological tests.

CONCLUSIONS

Our findings suggested that total nucleic acid extraction combined with NEB library generation is the most effective mNGS procedure in CSF pathogen detection. The optimization of positive criteria and databases can improve the specificity and sensitivity of mNGS diagnosis.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR1800015425 (29/03/2018), https://www.chictr.org.cn/edit.aspx?pid=26292&htm=4 .

Incidence of Childhood Meningoencephalitis in Children With a Suspected Meningoencephalitis in the Netherlands

Supplemental Digital Content is available in the text.

Complicated Streptococcus agalactiae Sepsis with/without Meningitis in Young Infants and Newborns: The Clinical and Molecular Characteristics and Outcomes

Background: Streptococcus agalactiae (also known as group B streptococcus, GBS) is associated with high mortality and morbidity rates in infants, especially those with complicated GBS sepsis, defined as those with meningitis, severe sepsis and/or septic shock. We aimed to characterize the clinical and molecular characteristics and risk factors for adverse outcomes of neonates with invasive GBS diseases. Methods: From 2003 to 2020, all neonates with invasive GBS diseases who were hospitalized in a tertiary-level neonatal intensive care unit (NICU) were enrolled. The GBS isolates underwent serotyping, multilocus sequence typing (MLST) and antibiotic susceptibility testing. We compared cases of complicated GBS sepsis with uncomplicated GBS bacteremia. Results: During the study period, a total of 188 neonates (aged less than 6 months old) with invasive GBS diseases were identified and enrolled. Among them, 119 (63.3%) had uncomplicated GBS bacteremia and 69 (36.7%) neonates had complicated GBS sepsis, including meningitis (25.5%, n = 48) and severe sepsis or septic shock. Among neonates with complicated GBS sepsis, 45 (65.2%) had neurological complications, and 21 (42.0%) of 50 survivors had neurological sequelae at discharge. The overall final mortality rate was 10.1% (19 neonates died). Type III/ST-17 GBS isolates accounted for 56.5% of all complicated GBS sepsis and 68.8% of all GBS meningitis, but this strain was not significantly associated with worse outcomes. The antimicrobial resistance rate among the invasive GBS isolates was obviously increasing in the past two decades. After multivariate logistic regression analysis, neonates with thrombocytopenia and respiratory failure were independently associated with final adverse outcomes. Conclusions: a total of 36.7% of all neonatal invasive GBS diseases were associated with complicated sepsis with/without meningitis. Given the high mortality and morbidity rates in neonates with complicated GBS sepsis, further studies for early identification of specific strains, risk factors or genetic mechanisms that will cause complicated GBS sepsis are urgently needed in the future.

Epidemiology of Pediatric Meningitis in South Korea From 2010 to 2018: A Population-based Retrospective Cohort Study

BACKGROUND

Studies evaluating the epidemiology of pediatric meningitis are limited in our region. This study aimed to describe recent trends in the incidence of pediatric meningitis.

METHODS

We estimated national trends in hospitalization rates for pediatric meningitis (<18 years) by analyzing data from the Health Insurance Review and Assessment database between 2010 and 2018. Meningitis cases were identified based on International Classification of Diseases, Tenth Revision (ICD-10) codes and hospitalization rates were calculated.

RESULTS

In this national population-based study, a total of 119,644 hospitalizations and 58 deaths due to pediatric meningitis were identified. The hospitalization rates of pediatric bacterial meningitis have declined by 50.0%, from 3.4 per 100,000 in 2010 to 1.7 per 100,000 in 2018. The mortality rates for bacterial and viral meningitis were 2.0% and 0.002%, respectively. Despite the decreased annual incidence of bacterial meningitis, its mortality rate did not change significantly during the study period. The only risk factor identified for mortality in bacterial meningitis patients among age group, sex, region of residence, and season was age below 1 year (P < 0.001). As children under 1 year have a high-mortality rate (4.2%), patients in this age group require close monitoring. The reasons behind indistinct seasonal patterns of bacterial meningitis warrant further investigation.

CONCLUSIONS

Childhood bacterial meningitis has shown a significant decline in incidence from 2010 to 2018. In contrast, viral meningitis has not shown a trend over time. Knowledge of these changes may aid clinicians in the decision-making process and management of meningitis patients.

Parent-administered Neurodevelopmental Follow up in Children After Picornavirus CNS Infections

BACKGROUND

Data on the neurodevelopment of children who experienced central nervous system (CNS) infections with enteroviruses (EV) or parechoviruses (hPeV) is scarce and mostly limited to follow up of short-term outcomes.

METHODS

Parents of children who presented between 2014 and 2019, underwent a lumbar puncture and whose cerebrospinal fluid was polymerase chain reaction positive for EV or hPeV, were asked to complete a care-giver-administered neurodevelopmental assessment tool (The Ages and Stages Instrument [ASQ3]). Clinical data of the infective episode were collected from patient notes.

RESULTS

Of 101 children, 43 (10 hPeV+, 33 EV+) submitted ASQ3 results. Median age at assessment was 38.9 months (interquartile range, 15.4-54.8), the follow-up interval 3 years (median 37 months; interquartile range, 13.9-53.1). Age, inflammatory markers, and cerebrospinal fluid pleocytosis during the infective event were not associated with ASQ3 scores. In 23 children (17 EV+, 6 hPeV+), no neurodevelopmental concerns were reported. Two more had preexisting developmental delay and were excluded. Of the remaining, 18/41 (43.9%) reported ASQ3 scores indicating need for monitoring or professional review in at least 1 category, not differing by pathogen (EV 14/31, 45.2%; hPeV 4/10, 40%; P = 0.71). Seven children will require formal review, scoring ≥2 SD below the mean in at least 1 category (6/31 EV+, 1/10 hPeV+, P = 0.7), 3 scored ≥2 SD below the mean in more than 1 area.

CONCLUSIONS

Parent-administered developmental assessment of children with a history of early picornavirus infection of the CNS identified a subgroup that requires formal neurodevelopmental review. Wider application of community-based developmental screening will complement our understanding of the impact of CNS infections in early childhood.

Update on Viral Infections Involving the Central Nervous System in Pediatric Patients

Infections of the central nervous system (CNS) are mainly caused by viruses, and these infections can be life-threatening in pediatric patients. Although the prognosis of CNS infections is often favorable, mortality and long-term sequelae can occur. The aims of this narrative review were to describe the specific microbiological and clinical features of the most frequent pathogens and to provide an update on the diagnostic approaches and treatment strategies for viral CNS infections in children. A literature analysis showed that the most common pathogens worldwide are enteroviruses, arboviruses, parechoviruses, and herpesviruses, with variable prevalence rates in different countries. Lumbar puncture (LP) should be performed as soon as possible when CNS infection is suspected, and cerebrospinal fluid (CSF) samples should always be sent for polymerase chain reaction (PCR) analysis. Due to the lack of specific therapies, the management of viral CNS infections is mainly based on supportive care, and empiric treatment against herpes simplex virus (HSV) infection should be started as soon as possible. Some researchers have questioned the role of acyclovir as an empiric antiviral in older children due to the low incidence of HSV infection in this population and observed that HSV encephalitis may be clinically recognizable beyond neonatal age. However, the real benefit-risk ratio of selective approaches is unclear, and further studies are needed to define appropriate indications for empiric acyclovir. Research is needed to find specific therapies for emerging pathogens. Moreover, the appropriate timing of monitoring neurological development, performing neuroimaging evaluations and investigating the effectiveness of rehabilitation during follow-up should be evaluated with long-term studies.

Distinguishing cytomegalovirus meningoencephalitis from other viral central nervous system infections

BACKGROUND

Hallmarks of cytomegalovirus (CMV) meningoencephalitis include fever, altered mental status, or meningismus with pleocytosis, elevated protein and hypoglycorrhachia on cerebrospinal fluid (CSF) analysis. Magnetic resonance imaging may show ventriculitis, ependymitis or periventricular enhancement. Studies are limited comparing clinical and laboratory characteristics to other viral etiologies.

OBJECTIVES

This multi-center, retrospective cohort analysis reviewed patients with CMV meningitis or encephalitis and compared clinical features, laboratory findings and outcomes to the most common viral causes of meningoencephalitis.

STUDY DESIGN

Patients with encephalitis or aseptic meningitis and detectable genetic material by polymerase chain reaction were identified. Clinical characteristics, laboratory findings and neuroimaging were collected from the electronic medical record. Data analysis was performed comparing CMV to other viral etiologies.

RESULTS

485 patients were evaluated and included cases of CMV (n = 36) which were compared with herpes simplex virus (n = 114), enterovirus (n = 207), varicella zoster virus (n = 41) and West Nile virus (n = 81). Human immunodeficiency virus (HIV) infection was seen more frequently in CMV infection compared with all other viral etiologies. Clinical presentations and CSF findings of other viral etiologies differ compared with CMV. Hypoglycorrhacia occurred more often with CMV compared with other viral pathogens. Outcomes were significantly worse compared with enterovirus, herpes simplex virus and varicella zoster virus but not West Nile virus.

CONCLUSIONS

CMV meningoencephalitis occurs most often in patients with HIV and encephalitis occurs more frequently than meningitis. Clinical and laboratory findings differ compared with other viral etiologies and can support consideration of CMV in the differential diagnosis of patients with meningoencephalitis.

Striking Decrease of Enteroviral Meningitis in Children During the COVID-19 Pandemic

We report the unprecedented complete absence of pediatric enteroviral meningitis in 2020 in the area of Bern, Switzerland. Presumably an unintended effect of coronavirus disease 2019 public health measures, this finding highlights the potential of community-wide nonpharmaceutical interventions for controlling the circulation of a major pediatric pathogen, which is mainly transmitted by the fecal-oral route.

The impact of viral infections on childhood central nervous system infections

BACKGROUND

Viruses are a common cause of central nervous system (CNS) infections. However, studies of CNS viral pathogens in pediatric patients are poorly explored because viral infections are often erroneously diagnosed as bacterial infections.

METHODS

299 CNS samples were collected from pediatric patients aged from one month to 14 years old. A total of 140 viral meningitis cases that met the inclusion criteria were included in this study. In 38 of the 140 cerebral spinal fluid (CSF) samples (27.1%), conventional and real-time PCR were used to identify viruses commonly associated with CNS infections.

RESULTS

Among them, 23 patients (16.5%) tested positive for flaviviruses such as dengue, Zika, and yellow fever virus, eight patients (5.7%) were positive for enterovirus (ENTV), and six patients (4.3%) were positive for human herpesvirus 1/2. We also identified one case of dengue virus and ENTV co-infection.

CONCLUSIONS

A correlation between clinical symptoms and laboratory findings for the viruses was identified. Our study also reinforces the importance of including viruses in the laboratory diagnosis of CNS infections especially flaviviruses, which assists public health authorities in implementing early interventions.

Analysis of enterovirus genotypes in the cerebrospinal fluid of children associated with aseptic meningitis in Liaocheng, China, from 2018 to 2019

BACKGROUND

Aseptic meningitis is most often caused by enteroviruses (EVs), but EVs associated with aseptic meningitis have not yet been reported in Liaocheng. The aim of this study was to determine the prevalence and genetic characteristics of EVs causing aseptic meningitis in children in Liaocheng.

METHODS

We reviewed the epidemiological and clinical characteristics of 504 paediatric cases of aseptic meningitis in Liaocheng from 2018 to 2019 and analysed the phylogeny of the predominant EV types causing this disease.

RESULTS

A total of 107 children were positive for EV in cerebrospinal fluid samples by nested PCR. Most of the positive patients were children 13 years old or younger and had symptoms such as fever, headache and vomiting (P < 0.05). The seasons with the highest prevalence of EV-positive cases were summer and autumn. The 107 EV sequences belonged to 8 serotypes, and echovirus types 18, 6 and 11 were the three dominant serotypes in Liaocheng during the 2-year study period. Phylogenetic analyses demonstrated that the E18 and E6 isolates belonged to subgenotype C2, while the E11 isolates belonged to subgenotype D5. VP1 analysis suggested that only one lineage of these three types was cocirculating in the Liaocheng region.

CONCLUSIONS

This study demonstrated the diverse EV genotypes contributing to a large outbreak of aseptic meningitis in Liaocheng. Therefore, large-scale surveillance is required to assess the epidemiology of EVs associated with aseptic meningitis and is important for the diagnosis and treatment of aseptic meningitis in Liaocheng.

The Epidemiology of Meningitis in Infants under 90 Days of Age in a Large Pediatric Hospital

Background: Meningitis is associated with substantial morbidity and mortality, particularly in the first three months of life. Methods: We conducted a retrospective review of patients <90 days of age with meningitis at Texas Children’s Hospital from 2010–2017. Cases were confirmed using the National Healthcare Safety Network (NHSN) definition of meningitis. Results: Among 694 infants with meningitis, the most common etiology was viral (n = 351; 51%), primarily caused by enterovirus (n = 332; 95%). A quarter of cases were caused by bacterial infections (n = 190; 27%). The most common cause of bacterial meningitis was group B Streptococcus (GBS, n = 60; 32%), followed by Gram-negative rods other than E. coli (n = 40; 21%), and E. coli (n = 37; 19%). The majority of Gram-negative organisms (63%) were resistant to ampicillin, and nearly one-fourth of Gram-negative rods (23%) other than E. coli and 2 (6%) E. coli isolates were resistant to third-generation cephalosporins. Significant risk factors for bacterial meningitis were early preterm birth and the Black race. Conclusions: Enteroviruses most commonly caused viral meningitis in infants; GBS was the most common bacterial cause despite universal screening and intrapartum prophylaxis. The emergence of MRSA and resistance to third-generation cephalosporins in Gram-negative bacterial meningitis challenges the options for empirical antimicrobial therapy.

Epidemiology, Etiology and Clinical Aspects of Childhood Acute Encephalitis in a Tertiary Pediatric Hospital in Costa Rica

BACKGROUND

Limited data are available on childhood encephalitis in Latin America. Our study aimed to increase insight on clinical presentation, etiology and outcome of children with acute encephalitis in Costa Rica.

METHODS

We conducted a prospective, observational study during an 8-month period at the Hospital Nacional de Niños "Dr. Carlos Sáenz Herrera" in Costa Rica. Case definition was according to "International Encephalitis Consortium" in children <13 years. We analyzed demographic characteristics, clinical symptoms, neurologic imaging, etiology, treatment and mortality.

RESULTS

Forty patients were identified. Mean age was 5 years and 57.5% were male. Most frequently neurologic symptoms were altered mental status (100.0%), headache (57.5%) and seizures (52.5%). Etiology was determined in 52.5% of cases. Probable or confirmed viral etiology was identified in 6 cases (15.0%) and bacterial etiology in also 6 cases (15.0%). A possible etiology was identified in 7 cases (17.5%). Autoimmune encephalitis was diagnosed in 2 patients (5.0%). Enterovirus and Streptococcus pneumoniae were the most common confirmed agents. No cases of herpes simplex virus were found. Etiology of 19 cases (47.5%) remained unknown. Sequelae were reported in 45.0% of patients. Mortality rate was 15.0% (6 cases), 3 caused by virus (adenovirus, human herpesvirus 6, enterovirus), 2 by bacteria (S. pneumoniae, Haemophilus influenzae type b) and 1 of unknown etiology. Diffuse cerebral edema was the most important mortality predictor (P < 0.001).

CONCLUSIONS

Acute encephalitis in our study was associated with significant morbidity and mortality. Early and aggressive antiviral, antibiotic and anticerebral edema treatment is necessary when acute encephalitis is suspected.

Encephalitis in Previously Healthy Children

Encephalitis is defined as altered mental status for more than 24 hours accompanied by 2 or more findings concerning for inflammation of the brain parenchyma: fever, seizures or other focal neurologic disorders, cerebrospinal fluid pleocytosis, and abnormal neuroimaging and electroencephalographic findings. Herpes simplex virus causes the most severe form of virus-induced encephalitis; the early administration of acyclovir can improve the prognosis of this disease. The rising interest in autoimmune causes of encephalitis, most notably anti-N-methyl-d-aspartate receptor, should prompt the clinician to consider immunomodulatory treatments, which may improve outcomes. A broad testing panel may be necessary to detect the etiologic agent; a few published pediatric cases suggest that infectious and autoimmune causes may occur concurrently in the same patient with encephalitis. More than 40% of children diagnosed as having encephalitis will not return to their previous level of neurologic function after resolution of their disease, although outcomes are highly variable depending on the etiologic agent.

Viruses Causing Aseptic Meningitis: A Tertiary Medical Center Experience With a Multiplex PCR Assay

Background: Central nervous system (CNS) infection is associated with high rates of morbidity and mortality, and despite advancements in molecular testing, aseptic meningitis remains challenging to diagnose. Aseptic meningitis cases are often underreported worldwide, which impacts the quality of patient care. Therefore, we aimed to assess the results of BioFire® FilmArray® meningitis/encephalitis (ME) PCR panel, clinical characteristics, and etiologies of aseptic meningitis patients.

Methods: From January 2018 to January 2020, all pediatric and adult patients in a large tertiary medical center who underwent lumbar puncture and cerebrospinal fluid (CSF) testing by a ME multiplex PCR panel and who fit the aseptic meningitis definition were retrospectively reviewed.

Results: Data were reviewed from 1,607 patients; 240 met the inclusion criteria (54.6% males; 68.8% <4 years of age). The rate of detected viral causes of aseptic meningitis was 40.4%; therefore, 59.6% of the patients remained with unidentified etiology. Among the identified viral meningitis, enterovirus and human herpesvirus 6 (HHV-6) were the most common (25 and 7.9%, respectively). The median length of hospital stay was 6 days, and it was longer in patients with unidentifiable aseptic meningitis (p < 0.0001).

Conclusion: Aseptic meningitis is common among suspected meningitis patients, but most cases remained of unknown etiology. The most common identified viruses were enterovirus followed by HHV-6, and there is predominance in males and the pediatric age group. These results highlight that further research is needed to identify other etiologies and possible additional viral pathogens for aseptic meningitis in the current diagnostic methods.

Management of Acute Bacterial Meningitis in Children

Acute community-acquired bacterial meningitis (ABM) in children continues to have high rates of neurological morbidity and mortality despite the overall declining rates of infection attributed to the use of vaccines and intrapartum Group B Streptococcus prophylaxis. Prompt diagnosis and early antibiotic therapy are crucial and should not be delayed to obtain cranial imaging. Differentiating bacterial from viral meningitis continues to be a clinical dilemma especially in patients with previous antibiotic exposure. Clinical models and inflammatory biomarkers can aid clinicians in their diagnostic approach. Multiplex polymerase chain reaction and metagenomic next-generation sequencing are promising tools that can help in early and accurate diagnosis. This review will present the epidemiology of ABM in children, indications of cranial imaging, role of different models and serum biomarkers in diagnosing ABM, and management including the use of adjunctive therapies and methods of prevention.

Evaluation of cerebrospinal fluid and blood parameters finding in early diagnosis and drug therapy of suspected bacterial meningitis in neonates

Background:

Whether early lumbar puncture (LP) and blood indicators are suitable as diagnostic criteria and helpful to treatment strategies for newborns remains to be solved. The study was to evaluate the value of cerebrospinal fluid (CSF) at the first LP and blood indicators at the similar time in the early diagnosis and the drug therapy of neonatal bacterial meningitis.

Materials and Methods:

We conducted a retrospective observational study of 997 infants with suspected bacterial meningitis between June 2012 and June 2018. CSF and blood parameters were evaluated by three stepwise logistic models to assess their ability: to distinguish bacterial meningitis from nonbacterial meningitis, to distinguish positive CSF culture from negative, and to distinguish Gram-positive bacteria from negative.

Results:

Of the 997 neonates, 236 (23.67%) were later diagnosed as bacterial meningitis. Of the neonates with meningitis, 54 (22.88%) had positive CSF culture results. And of neonates with positive CSF culture, 27 (50%) had Gram-positive results. One or more CSF indicators were added to the three models. Only blood hypersensitive C-reactive protein and blood lactate dehydrogenase were added to the first model, while no blood parameters was added to the other two models. The areas under the effect-time curves of the three models were 0.91 (95% confidence interval [CI]: 0.89–0.92, P < 0.001), 0.69 (95% CI: 0.63–0.75, P < 0.001), and 0.86 (95% CI: 0.74–0.94, P < 0.001), respectively.

Conclusion:

LP was irreplaceable predictor of bacterial meningitis, and comprehensive analysis of CSF indicators can predict the offending organism, which enables refinement of therapy.

Utilization, Yield, and Accuracy of the FilmArray Meningitis/Encephalitis Panel with Diagnostic Stewardship and Testing Algorithm

The impact of diagnostic stewardship and testing algorithms on the utilization and performance of the FilmArray meningitis/encephalitis (ME) panel has received limited investigation. We performed a retrospective single-center cohort study assessing all individuals with suspected ME between February 2017 and April 2019 for whom the ME panel was ordered. Testing was restricted to patients with cerebrospinal fluid (CSF) pleocytosis. Positive ME panel results were confirmed before reporting through correlation with direct staining (Gram and calcofluor white) and CSF cryptococcal antigen or by repeat ME panel testing. Outcomes included the ME panel test utilization rate, negative predictive value of nonpleocytic CSF samples, test yield and false-positivity rate, and time to appropriate deescalation of acyclovir. Restricting testing to pleocytic CSF samples reduced ME panel utilization by 42.7% (263 versus 459 tests performed) and increased the test yield by 61.8% (18.6% versus 11.5% positivity rate; P < 0.01) with the application of criteria. The negative predictive values of a normal CSF white blood cell (WBC) count for ME panel targets were 100% (195/195) for nonviral targets and 98.0% (192/196) overall. All pathogens detected in nonpleocytic CSF samples were herpesviruses. The application of a selective testing algorithm based on repeat testing of nonviral targets avoided 75% (3/4) of false-positive results without generating false-negative results. The introduction of the ME panel reduced the duration of acyclovir treatment from an average of 66 h (standard deviation [SD], 43 h) to 46 h (SD, 36 h) (P = 0.03). The implementation of the ME panel with restriction criteria and a selective testing algorithm for nonviral targets optimizes its utilization, yield, and accuracy.

Rapid Diagnostic Tests for Meningitis and Encephalitis-BioFire

Meningitis and encephalitis (ME) are important causes of morbidity and mortality worldwide. Patients suspected of having ME are often hospitalized and started on empiric antimicrobial treatment, because of the potential adverse consequences of delaying the diagnosis or treatment. Multiplexed polymerase chain reaction panels are one of several rapid diagnostic technologies that have the potential to overcome some of the limitations of conventional diagnostic methods for ME. The BioFire FilmArray Meningitis/Encephalitis Panel was the first Food and Drug Administration-cleared multiplex polymerase chain reaction for the evaluation of cerebrospinal fluid samples, able to identify 14 organisms in a single test reaction. This newer rapid diagnostic tool has an overall high sensitivity and specificity for the diagnosis of ME with a fast turnaround time and has the potential to improve resource utilization for patients presenting with suspicion of ME. However, further research is needed to determine its optimal use in the evaluation of patients with suspected ME.

Etiology, Clinical Presentation and Incidence of Infectious Meningitis and Encephalitis in Polish Children

Little is known about the causes and the frequency of meningitis and encephalitis in Poland. We did a retrospective single-center cohort study of children under 18 years old hospitalized with infectious meningitis or encephalitis. Incidence rates were calculated using collected data from patients from the North-East Poland only. A total of 374 children hospitalized between 1 January 2015 and 31 December 2019 were included in the study. A total of 332 (89%) children had meningitis, and 42 (11%) had encephalitis. The etiology of the infection was established in 331 (89%) cases. Enteroviruses accounted for 224 (60%) of all patients. A total of 68 (18%) cases were tick-borne infections. Bacterial pathogens were detected in 26 (7%) children. The median length of hospital stay for children with enteroviral meningitis was 7 days (IQR 7–9), increasing to 11 days (8–13) in those treated with antibiotics. The incidence of meningitis was estimated to be 32.22 (95% CI, 25.33–40.98) per 100,000 and that of encephalitis to be 4.08 (95% CI, 2.07–8.02) per 100,000. By the broad use of molecular diagnostic methods, we managed to identify etiology of the infection in the majority of children. Our data suggest that thorough diagnostics of central nervous system infections are needed to rationalize treatment.

Readmissions after hospital care for meningitis in the United States

BACKGROUND

Our objectives were to (1) characterize patient and clinical characteristics of adults hospitalized with meningitis; (2) describe meningitis hospitalization outcomes, including 30- and 90-day readmissions; and (3) determine whether clinical, patient, or index hospitalization characteristics are associated with readmission and readmission outcomes.

METHODS

This retrospective study of the 2014 National Readmissions Database extracted data on hospitalized adults with a principal diagnosis of meningitis and examined hospitalization outcomes using descriptive statistics. Logistic regression models were built to determine whether characteristics were associated with 30- or 90-day readmissions.

RESULTS

For the 30-day readmission analyses, 18,883 adults qualified. Meningitis hospitalizations commonly involved adults 25 to 54 years of age who were insured by private carriers. The readmission rates were 7.0% at 30 days and 11.4% at 90 days. Readmission was associated with greater comorbidity burden (2 conditions: adjusted odds ratio [AOR] = 1.60, range 1.24-2.08; 3 conditions: AOR = 1.92, range 1.43-2.58; 4+ conditions: AOR = 2.68, range 2.04-3.51 vs 0 or 1 condition), public insurance (Medicare: AOR = 1.85, range 1.30-2.62; Medicaid: AOR = 1.48, range 1.16-1.90 vs private insurance), and medical error (AOR = 1.43, range 1.07-1.91). Readmissions were most often for meningitis, septicemia, or medical complications.

CONCLUSIONS

Readmission after hospitalization for meningitis is associated with both fixed and modifiable factors. More research is needed to determine which post-meningitis readmissions are preventable.

Update and advances in community acquired bacterial meningitis

PURPOSE OF REVIEW

Community-acquired bacterial meningitis continues to occur and be associated with significant morbidity and mortality despite the availability of effective conjugate vaccines for the three most important meningeal pathogens.

RECENT FINDINGS

Indications for cranial imaging in suspected bacterial meningitis varies significantly between guidelines. Cranial imaging is of no clinical utility in those patients without indications and fosters delays in performing a lumbar puncture. Delaying lumbar puncture is associated with increased costs in both adults and children with meningitis and previous antibiotic therapy impacts the yield of microbiological results. Delaying antibiotic therapy is associated with worse clinical outcomes. Adjunctive steroids have reduced the mortality of adults with pneumococcal meningitis but have been associated with increased adverse outcomes in Listeria monocytogenes and Cryptococcus neoformans.

SUMMARY

Community-acquired bacterial meningitis remains a global health concern with high morbidity and mortality especially in low-income countries. Cranial imaging should be done only in patients with an indication with an attempt to do a prompt lumbar puncture and to initiate antibiotic therapy and adjunctive steroids as soon as possible to improve clinical outcomes.

Molecular Pathogenicity of Enteroviruses Causing Neurological Disease

Enteroviruses are single-stranded positive-sense RNA viruses that primarily cause self-limiting gastrointestinal or respiratory illness. In some cases, these viruses can invade the central nervous system, causing life-threatening neurological diseases including encephalitis, meningitis and acute flaccid paralysis (AFP). As we near the global eradication of poliovirus, formerly the major cause of AFP, the number of AFP cases have not diminished implying a non-poliovirus etiology. As the number of enteroviruses linked with neurological disease is expanding, of which many had previously little clinical significance, these viruses are becoming increasingly important to public health. Our current understanding of these non-polio enteroviruses is limited, especially with regards to their neurovirulence. Elucidating the molecular pathogenesis of these viruses is paramount for the development of effective therapeutic strategies. This review summarizes the clinical diseases associated with neurotropic enteroviruses and discusses recent advances in the understanding of viral invasion of the central nervous system, cell tropism and molecular pathogenesis as it correlates with host responses.

Cerebrospinal Fluid Findings Are Poor Predictors of Appropriate FilmArray Meningitis/Encephalitis Panel Utilization in Pediatric Patients

Molecular testing of cerebrospinal fluid (CSF) using the BioFire FilmArray meningitis/encephalitis (FA-M/E) panel permits rapid, simultaneous pathogen detection. Due to the broad spectrum of targeted organisms, FA-M/E testing may be restricted to patients with abnormal CSF findings. We sought to determine if restriction is appropriate in our previously healthy and/or immunocompromised pediatric patients. FA-M/E was ordered on 1,025 CSF samples from 948 patients; 121 (11.8%) specimens were FA-M/E positive. Of these, 89 (73.6%) were virus positive, and 30 (24.8%) were bacterium positive. The most common targets detected were enterovirus (n = 38), human herpesvirus 6 (HHV-6) (n = 30), and Streptococcus pneumoniae (n = 14). Pleocytosis with white blood cell (WBC) levels of ≥5 cells/mm³ and ≥10 cells/mm³ were found in 33.1% and 24.3% of all specimens, respectively. Using WBC levels of ≥5 cells/mm³, 63.4% (59/93) of positive specimens exhibited pleocytosis, compared to 29.5% (233/789) of negative specimens. Among positive specimens, 54.4% (37/68) of viral and 87% (20/23) of bacterial cases had pleocytosis. The use of a pleocytosis cutoff of ≥10 cells/mm³ would have missed an additional enterovirus, one cytomegalovirus (CMV), and two HHV-6 diagnoses. CSF glucose and protein levels were normal for 83/116 (75.2%) and 51/116 (44%) positive specimens. Abnormal glucose in combination with WBC levels of ≥10 cells/mm³ showed high specificity (94.5%) and was a better predictor of FA-M/E positivity than abnormal protein. Sensitivity and positive predictive values were <90% for all biomarkers. CSF pleocytosis and abnormal glucose/protein were poor predictors of FA-M/E. Restricting FA-M/E orders based on pleocytosis or other abnormal parameters would have resulted in missed diagnostic opportunities, particularly for the detection of viruses in both previously healthy and immunocompromised patients.

Cytokine characteristic of cerebrospinal fluid from children with enteroviral meningitis compared to bacterial meningitis

Background

Enteroviruses are the most common etiological agent for viral encephalitis, but it is uncertain whether the cytokines have the ability to differentiate enteroviral meningitis (EVM) from bacterial meningitis (BM).

Methods

A retrospective study was performed at the Children's Hospital, Zhejiang University School of Medicine from August 2016 and August 2019. CSF and/or blood specimens were collected for microbiological culture, viruses, and cytokine detection.

Results

Forty‐three patients were confirmed with meningitis, 27 patients with EVM, and 16 with BM. Children with EVM were older compared with BM and Control group (P < .001). The most common presenting symptom in children with EVM was fever (96.3%) followed by headache (88.9%) and vomiting (66.7%). The occurrence of seizure was lower in both EVM and BM groups (P < .001). Serum IL‐6 and serum IL‐10 were lower in EVM group than BM (P = .02) and control group (IL‐6, P = .01; IL‐10, P < .001). IL‐6, IL‐10, and IFN‐γ levels showed obviously increase in CSF (P < .001, respectively) in EVM group, while only IL‐6 increased in CSF (P < .001) in BM group. CSF concentrations of cytokines IL‐6, IL‐10, TNF, and IFN‐γ in children with EVM and BM were both higher than Control group (P < .001). But compared EVM group to BM group, CSF IL‐2 (P = .13), IL‐6 (P = .37), IL‐10 (P = .98), TNF (P = .54), and IFN‐γ (P = .53) showed no difference between two groups.

Conclusions

CSF cytokines elevated in both virus and bacterial meningitis, while serum elevation only occurred in bacterial infection. Still, we could not distinguish enteroviral meningitis from bacterial meningitis with the parameters of CSF cytokines IL‐2, IL‐6, IL‐10, TNF, and IFN‐γ.

Development and validation of a multiplex-PCR based assay for the detection of 18 pathogens in the cerebrospinal fluid of hospitalized children with viral encephalitis

BACKGROUND

The Applied Biosystems 3500 Genetic Analyzer (ABI3500) allows for automated capillary electrophoresis on multiple targets. So far, the application of this method for detecting cerebrospinal fluid pathogens has hardly been reported.

METHODS

To assess the performance of multiplex-PCR assay for 18 pathogens detection, 127 CSF samples from hospitalized children with suspected viral encephalitis were prospectively collected from April to November 2018. The Sanger sequencing was applied to verify this assay.

RESULTS

All of the 18 target pathogens can be identified by multiplex-PCR assay at 10⁴ copies (or CFU/mL) of each virus, bacterium and fungus. In contrast, 10 control microorganisms failed to be amplified. Approximately 68.5 % of the cases tested had positive results, the enterovirus accounted for the majority of the positive cases (63.8 %). Agreement between multiplex-PCR and sequencing was 91.49 %.

CONCLUSIONS

Our findings suggest that the ABI3500-based multiplex-PCR detection kit could be a valuable diagnostic tool for pathogen detection in CSF of children with suspected viral encephalitis.

Consistent, Excess Viral Meningitis Incidence Rates in Young Males: A Multi-country, Multi-year, Meta-analysis of National Data. The Importance of Sex as a Biological Variable

BACKGROUND

Sex can be an important biological variable in the immune response to infections and the response to vaccines. The magnitude and consistency in age-specific sex differences in the incidence of viral infections remain unclear.

METHODS

We obtained data from national official agencies on cases of viral meningitis by sex and age group over a period of 6-16 years from five countries: Canada, Czech Republic, Germany, Israel, and Poland. Male to female incidence rate ratios (RR) were computed for each year, by country, and age group. For each age group, we used meta-analysis methodology to combine the incidence RRs. Meta-regression was conducted to the estimate the effects of age, country, and time period on the RR.

FINDINGS

In the age groups < 1, 1-4, 5-9, 10-14, there were consistently higher incidence rates in males, over countries and time. The pooled incidence RRs (with 95% CI) were 1.38 (1.30-1.47), 1.94 (1.85-2.03), 1.98 (1.88-2.07), and 1.58 (1.47-1.71) respectively. In young and middle-age adults there were no differences with pooled incidence RRs of 1.00 (0.97-1.03), and 0.97 (0.94-1.00), respectively. Sensitivity analysis confirms that the results are stable and robust. Meta-regression showed that almost all the variations in the incidence RRs were contributed by age group.

INTERPRETATION

The higher incidence rates from viral meningitis in males under the age of 15 are remarkably consistent across countries and time-periods. These findings emphasize the importance of sex as a biological variable in infectious diseases. This could provide keys to the mechanisms of infection and lead to more personalized treatment and vaccine doses and schedules.

FUNDING

There was no funding source for this article.

Flaviviruses as agents of childhood central nervous system infections in Brazil

Flaviviruses are agents of a major emerging human public health issue and members of this genus have been associated with central nervous system (CNS) infections. In Brazil, a country endemic for some arboviruses, the most clinically relevant neurotropic flaviviruses include Dengue virus and Zika virus. Flaviviruses cause diseases ranging from mild or sub-clinical infections to severe cases as CNS infections. There is a lack of data about the incidence of flaviviruses in the CNS of children in Brazil. In this review, we provide a general overview of several flaviviruses that cause CNS infections in Brazilian children and explore the importance of epidemiological surveillance of CNS infections in cases of flavivirus infections.

Usefulness of the FilmArray meningitis/encephalitis (M/E) panel for the diagnosis of infectious meningitis and encephalitis in Taiwan

BACKGROUND/PURPOSE

Early recognition of causative pathogens is critical for the appropriate management of central nervous system infection and improved outcomes. The BioFire^® FilmArray^® Meningitis/Encephalitis Panel (BioFire^® ME Panel, BioFire Diagnostics) is the first U.S. Food and Drug Administration (FDA)-approved multiplex PCR assay that allows the rapid detection of 14 pathogens, including bacteria (n = 6), viruses (n = 7), and fungi (n = 1), from cerebrospinal fluid (CSF). The performance of the panel is expected to be dependent on the epidemiology of M/E in different geographical regions.

METHODS

In this preliminary study, we used the BioFire^® ME Panel in 42 subjects who presented to the emergency department with symptoms of M/E in our hospital. The results were compared to conventional culture, antigen detection, PCR, and various laboratory findings.

RESULTS

The panel detected six positive samples, of which five were viral and one bacterial. We observed an overall agreement rate of 88% between the BioFire^® ME Panel results and the conventional methods. There were no false-positive findings, but five discordant results were observed for enterovirus, herpes simplex virus type 1, Escherichia coli, and Cryptococcus species.

CONCLUSIONS

The BioFire^® ME Panel performed equivalently to the traditional PCR methods for virus detection, and better than bacterial cultures. This revolutionary system represents a paradigm shift in the diagnosis of M/E and may aid in the rapid identification of community-acquired M/E. However, the usefulness of this tool is limited in regions with a high prevalence of infectious M/E caused by microorganisms not included in the panel.

Flaviviruses as agents of childhood central nervous system infections in Brazil

Flaviviruses are agents of a major emerging human public health issue, and members of the Flavivirus genus have been associated with central nervous system (CNS) infections. In Brazil, a country endemic for some arboviruses, the most clinically relevant neurotropic flaviviruses include dengue virus and Zika virus. Flaviviruses cause diseases ranging from mild or subclinical infections to severe cases as CNS infections. There is a lack of data about the incidence of flaviviruses in the CNS of children in Brazil. In this review, we provide a general overview of several flaviviruses that cause CNS infections in Brazilian children and explore the importance of epidemiologic surveillance of CNS infections in cases of Flavivirus infections.

Clinical Utilization of the FilmArray Meningitis/Encephalitis (ME) Multiplex Polymerase Chain Reaction (PCR) Assay

Objective: To assess the clinical utilization and performance of the FilmArray® Meningitis/Encephalitis (ME) multiplex polymerase chain reaction (PCR) panel in a hospital setting.

Background: Rapid diagnosis and treatment of central nervous system (CNS) infections are critical to reduce morbidity and mortality. The ME panel is a Food and Drug Administration (FDA) approved rapid multiplex PCR assay that targets 14 bacteria, viruses, and fungi. Previous studies show an overall agreement of 93–99% between the ME panel and conventional diagnostic testing. However, few studies have evaluated the clinical implementation of the ME assay, which is available for routine use at our institution.

Methods: We performed a single center retrospective chart review of inpatients who underwent ME panel testing from August 2016 to May 2017. Clinical, radiologic, and laboratory data were reviewed to determine the clinical significance of results. Indication for lumbar puncture (LP), time to results of the ME panel, and duration of antimicrobial therapy were evaluated.

Results: Seven hundred and five inpatients underwent ME testing, of whom 480 (68.1%) had clinical suspicion for CNS infection with 416 (59.0%) receiving empiric antimicrobial treatment for CNS infection. The median time-to-result of the ME panel was 1.5 h (IQR, 1.4–1.7). Overall agreement between the ME panel results and clinico-laboratory assessment was 98.2%. Forty-five patients tested positive by ME, of which 12 (26.6%) were determined likely to be clinically insignificant.

Conclusions: Routine availability of the ME panel led to overutilization of diagnostic test ordering, as demonstrated by the fact that over one-third of ME panel tests performed were ordered for patients with little or no suspicion for CNS infection. The median time from LP to ME panel result was 1.5 h (IQR, 1.4–1.7). The ME panel's rapid turn-around time contributed to the overuse of the test. Approximately one-quarter of positive ME results were deemed clinically insignificant, though the impact of these positive results requires additional evaluation. Twenty-four and forty-eight hours after the ME panel resulted, 68 and 25% of patients started on empiric therapy remained on antibiotics, respectively. The median time from diagnosis to discontinuation and/or narrowing of antibiotic coverage was 25.6 h (IQR, 3.6–42.5). Further consideration of the appropriate indications for use of the ME panel in clinical settings is required.