Neonatal meningitis in England and Wales: sequelae at 5 years of age

Systematic review and meta-analysis of intraventricular antibiotics for neonatal meningitis and ventriculitis

PURPOSE

We aimed to determine the safety and effectiveness of intraventricular antibiotics in neonates with meningitis and/or ventriculitis and analyze the quality of available evidence.

METHODS

DESIGN: Systematic review and meta-analysis.

DATA SOURCES

PubMed, EMBASE, LILACS, and SCOPUS up to 17 February 2023.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomized experimental and observational studies were included. The Cochrane methodology was used for systematic reviews.

RESULTS

Twenty-six observational studies and one randomized clinical trial involving 272 patients were included. The risk of bias in both pediatric and neurosurgical studies was high, and the quality of evidence was low (evidence level C). In the pediatric studies, no significant differences in mortality were found between intraventricular antibiotics and only systemic antibiotic [25.4% vs 16.1%, OR = 0.96 (0.42-2.24), P = 0.93]. However, when analyzing the minimum administered doses, we found a lower mortality when a minimum duration of 3 days for intraventricular antibiotics was used compared to only systemic antibiotic [4.3% vs 17%, OR = 0.22 (0.07-0.72), P = 0.01]. In the neurosurgical studies, the use of intraventricular antibiotics in ventriculitis generally results in a mortality of 5% and a morbidity of 25%, which is lower than that in cases where intraventricular antibiotics were not used, with an average mortality of 37.3% and a morbidity of 50%.

CONCLUSION

Considering the low quality of evidence in pediatric and neurosurgical studies, we can conclude with a low level of certainty that intraventricular antibiotics may not significantly impact mortality in neonatal meningitis and ventriculitis. However, reduced mortality was observed in cases treated with a minimum duration of 3 days of intraventricular antibiotic, particularly the multidrug-resistant or treatment-refractory infections. Higher-quality studies are needed to improve the quality of evidence and certainty regarding the use of intraventricular antibiotics for treating neonatal meningitis and ventriculitis.

Long-term impact of serious neonatal bacterial infections on neurodevelopment

BACKGROUND

Neonatal bacterial infections have long been recognized as an important cause of acute morbidity and mortality, but long-term neurodevelopmental consequences have not been comprehensively described and discussed.

OBJECTIVES

We aimed to summarize evidence on the pathogenesis, diagnosis, and epidemiology of long-term sequelae after neonatal bacterial sepsis and meningitis. We also discuss approaches for future studies to quantify the public health impact of neonatal infection-associated neurodevelopmental impairment.

SOURCES

We identified studies, both research articles and reviews, which provide mechanistic information on the long-term disease, as well as epidemiological studies that describe the frequency of neurodevelopmental impairment in children with and, for comparison, without a history of neonatal bacterial infection. Tools currently used in clinical practice and research settings to assess neurodevelopmental impairment were also reviewed.

CONTENT

We first enumerate potential direct and indirect mechanisms that can lead to brain injury following neonatal infections. We then discuss summary data, either frequencies or measures of association, from epidemiological studies. Risk factors that predict long-term outcomes are also described. Finally, we describe clinical approaches for identifying children with neurodevelopmental impairment and provide an overview of common diagnostic tools.

IMPLICATIONS

The limited number of studies that describe the long-term consequences of neonatal infections, often undertaken in high-income settings and using variable designs and diagnostic tools, are not sufficient to inform clinical practice and policy prioritization. Multi-country studies with follow-up into adolescence, standardized diagnostic approaches, and local comparator groups are needed, especially in low and middle-income countries where the incidence of neonatal sepsis is high.

Neonatal bacterial meningitis: hearing screening and audiological monitoring outcomes

OBJECTIVE

This study reviewed the outcomes of universal newborn hearing screening (UNHS) and ongoing hearing monitoring in children following recovery from neonatal bacterial meningitis to determine (a) whether screening may be a suitable alternative to diagnostic audiology for detecting permanent childhood hearing loss (PCHL) and (b) whether infants who pass UNHS should be monitored throughout childhood.

DESIGN

Retrospective analysis of a UNHS database.

STUDY SAMPLE

Data were extracted from the state-wide UNHS database for all children born in Queensland Australia between 1 September 2004 and 30 June 2020 with the risk factor of bacterial meningitis (in isolation or in combination with other risk factors) identified at the time of the UNHS. This cohort included 231 children.

RESULTS

Results showed that all post-meningitic infants diagnosed with PCHL had a refer result on the UNHS or were medically excluded from screening. Additionally, no cases of PCHL were identified through the targeted surveillance program following a pass result on UNHS.

CONCLUSIONS

UNHS may be sufficient to detect PCHL in post-meningitic neonates and routine audiological monitoring may not be required for children who pass the screen.

Comparison of bacterial culture with BioFire® FilmArray® multiplex PCR screening of archived cerebrospinal fluid specimens from children with suspected bacterial meningitis in Nigeria

BACKGROUND

Diagnosis of bacterial meningitis remains a challenge in most developing countries due to low yield from bacterial culture, widespread use of non-prescription antibiotics, and weak microbiology laboratories. The objective of this study was to compare the yield from standard bacterial culture with the multiplex nested PCR platform, the BioFire® FilmArray® Meningitis/Encephalitis Panel (BioFire ME Panel), for cases with suspected acute bacterial meningitis.

METHODS

Following Gram stain and bacterial culture on cerebrospinal fluid (CSF) collected from children aged less than 5 years with a clinical suspicion of acute bacterial meningitis (ABM) as defined by the WHO guidelines, residual CSF specimens were frozen and later tested by BioFire ME Panel.

RESULTS

A total of 400 samples were analyzed. Thirty-two [32/400 (8%)] of the specimens were culture positive, consisting of; three Salmonella spp. (2 Typhi and 1 non-typhi), three alpha hemolytic Streptococcus, one Staphylococcus aureus, six Neisseria meningitidis, seven Hemophilus influenzae, 11 Streptococcus pneumoniae and 368 were culture negative. Of the 368 culture-negative specimens, the BioFire ME Panel detected at least one bacterial pathogen in 90 (24.5%) samples, consisting of S. pneumoniae, N. meningitidis and H. influenzae, predominantly. All culture positive specimens for H. influenzae, N. meningitidis and S. pneumoniae also tested positive with the BioFire ME Panel. In addition, 12 specimens had mixed bacterial pathogens identified. For the first time in this setting, we have data on the viral agents associated with meningitis. Single viral agents were detected in 11 (2.8%) samples while co-detections with bacterial agents or other viruses occurred in 23 (5.8%) of the samples.

CONCLUSIONS

The BioFire® ME Panel was more sensitive and rapid than culture for detecting bacterial pathogens in CSF. The BioFire® ME Panel also provided for the first time, the diagnosis of viral etiologic agents that are associated with meningoencephalitis in this setting. Institution of PCR diagnostics is recommended as a routine test for suspected cases of ABM to enhance early diagnosis and optimal treatment.

Microbial signatures of neonatal bacterial meningitis from multiple body sites

As a common central nervous system infection in newborns, neonatal bacterial meningitis (NBM) can seriously affect their health and growth. However, although metagenomic approaches are being applied in clinical diagnostic practice, there are some limitations for whole metagenome sequencing and amplicon sequencing in handling low microbial biomass samples. Through a newly developed ultra-sensitive metagenomic sequencing method named 2bRAD-M, we investigated the microbial signatures of central nervous system infections in neonates admitted to the neonatal intensive care unit. Particularly, we recruited a total of 23 neonates suspected of having NBM and collected their blood, cerebrospinal fluid, and skin samples for 2bRAD-M sequencing. Then we developed a novel decontamination method (Reads Level Decontamination, RLD) for 2bRAD-M by which we efficiently denoised the sequencing data and found some potential biomarkers that have significantly different relative abundance between 12 patients that were diagnosed as NBM and 11 Non-NBM based on their cerebrospinal fluid (CSF) examination results. Specifically, we discovered 11 and 8 potential biomarkers for NBM in blood and CSF separately and further identified 16 and 35 microbial species that highly correlated with the physiological indicators in blood and CSF. Our study not only provide microbiological evidence to aid in the diagnosis of NBM but also demonstrated the application of an ultra-sensitive metagenomic sequencing method in pathogenesis study.

Lumbar Puncture and Meningitis in Infants with Proven Early- or Late-Onset Sepsis: An Italian Prospective Multicenter Observational Study

Background: To evaluate the rates of lumbar puncture (LP) in infants with culture-proven sepsis. Study design: We prospectively enrolled 400 infants with early- or late-onset sepsis due to Group B streptococcus (GBS) or Eschericha coli, diagnosed within 90 days of life. Rates of LP and potential variables associated with LP performance were evaluated. Moreover, cerebrospinal fluid (CSF) characteristics and results of the molecular analysis were investigated. Results: LP was performed in 228/400 (57.0%) infants; 123/228 LPs (53.9%) were performed after antibiotic initiation, hampering the ability to identify the pathogen in the CSF culture. However, polymerase chain reaction increased the probability of positive results of CSF analysis compared to microbiological culture (28/79, 35.4% vs. 14/79, 17.7%, p = 0.001). Severe clinical presentation and GBS infection were associated with higher LP rates. The rate of meningitis was 28.5% (65/228). Conclusions: Rates of LP are low in culture-proven neonatal sepsis and antibiotics are frequently given before LP is carried out. Thus meningitis may be underestimated, and the chances of giving an effective therapy to the newborn are reduced. LP should be performed before the start of antibiotics when there is a clinical suspicion of infection.

Isolation and Characterization of Lytic Bacteriophages Active against Clinical Strains of E. coli and Development of a Phage Antimicrobial Cocktail

Pathogenic E. coli cause urinary tract, soft tissue and central nervous system infections, sepsis, etc. Lytic bacteriophages can be used to combat such infections. We investigated six lytic E. coli bacteriophages isolated from wastewater. Transmission electron microscopy and whole genome sequencing showed that the isolated bacteriophages are tailed phages of the Caudoviricetes class. One-step growth curves revealed that their latent period of reproduction is 20-30 min, and the average value of the burst size is 117-155. During co-cultivation with various E. coli strains, the phages completely suppressed bacterial host culture growth within the first 4 h at MOIs 10^-7 to 10^-3. The host range lysed by each bacteriophage varied from six to two bacterial strains out of nine used in the study. The cocktail formed from the isolated bacteriophages possessed the ability to completely suppress the growth of all the E. coli strains used in the study within 6 h and maintain its lytic activity for 8 months of storage. All the isolated bacteriophages may be useful in fighting pathogenic E. coli strains and in the development of phage cocktails with a long storage period and high efficiency in the treatment of bacterial infections.

Utility of Cerebrospinal Fluid and Serum Procalcitonin for the Diagnosis of Neonatal Meningitis

OBJECTIVE

Positive CSF culture is the gold standard for the diagnosis of meningitis but it carries poor sensitivity. CSF procalcitonin (PCT) is shown to have some utility for the diagnosis of meningitis though there are limited studies in neonatal age group. We planned this study to compare CSF, serum, and CSF to serum PCT levels in neonates with confirmed, probable, and nonmeningitis groups to determine its optimal cut-off in CSF and serum for diagnosing meningitis.

STUDY DESIGN

Sixty-seven neonates who qualified for lumbar puncture were enrolled in the study. Neonates were categorized into confirmed meningitis, i.e., CSF cytochemistry and culture positive (N = 17), probable meningitis, i.e., CSF cytochemistry positive but culture negative (N = 25) and nonmeningitis, i.e., both cytochemistry and culture negative (N = 25). CSF and serum samples were stored at -80°C for PCT assay.

RESULTS

Significant difference was seen in mean of CSF PCT in neonates with confirmed (0.31 ng/mL), probable (0.22 ng/mL), and nonmeningitis (0.11 ng/mL) groups. Similarly, significant difference was observed in serum PCT levels also, though the ratio of serum to CSF PCT was comparable. At cut-off of 0.2 ng/mL, CSF PCT had sensitivity of 95.2% and specificity of 96% in the diagnosis of meningitis.

CONCLUSION

CSF PCT is more specific marker for the diagnosis of neonatal meningitis as compared with serum PCT and CSF to serum PCT ratio.

KEY POINTS

· CSF procalcitonin is a better marker than serum procalcitonin for diagnosing neonatal meningitis.. · It is better than serum procalcitonin and CSF to serum procalcitonin ratio.. · At cut-off of >0.2 ng/mL CSF procalcitonin can diagnose neonatal meningitis with 96% specificity..

Neural Injury and Repair in a Novel Neonatal Mouse Model of Listeria Monocytogenes Meningoencephalitis

To improve the therapy of neonatal central nervous system infections, well-characterized animal models are urgently needed. The present study analyzes neuropathological alterations with particular focus on neural injury and repair in brains of neonatal mice with Listeria monocytogenes (LM) meningitis/meningoencephalitis using a novel nasal infection model. The hippocampal formation and frontal cortex of 14 neonatal mice with LM meningitis/meningoencephalitis and 14 uninfected controls were analyzed by histology, immunohistochemistry, and in situ tailing for morphological alterations. In the dentate gyrus of the hippocampal formation of mice with LM meningitis/meningoencephalitis, an increased density of apoptotic neurons visualized by in situ tailing (p = 0.04) and in situ tailing plus immunohistochemistry for activated Caspase-3 (p < 0.0001) was found. A decreased density of dividing cells stained with an anti-PCNA-antibody (p < 0.0001) and less neurogenesis visualized by anti-calretinin (p < 0.0001) and anti-calbindin (p = 0.01) antibodies were detected compared to uninfected controls. The density of microglia was higher in LM meningitis (p < 0.0001), while the density of astrocytes remained unchanged. Infiltrating monocytes and neutrophilic granulocytes likely contributed to tissue damage. In conclusion, in the brains of LM-infected mice a strong immune response was observed which led to neuronal apoptosis and an impaired neural regeneration. This model appears very suitable to study therapies against long-term sequelae of neonatal LM meningitis.

Epidemiology and Trends of Infective Meningitis in Neonates and Infants Less than 3 Months of Age in Hong Kong

INTRODUCTION AND AIMS

Meningitis in neonates and young infants leads to significant morbidity and mortality worldwide. This study aims to investigate pathogens, antibiotics resistance and secular change of incidence in Hong Kong.

METHODS

We performed a retrospective search on meningitis in neonates and infants <3 months old in three Hong Kong public hospitals from 2004 to 2019. Medical charts were reviewed, focusing on the identification and antibiotics resistance of the pathogens.

RESULTS

200 cases of meningitis were identified (67% were bacterial). Group B Streptococcus (GBS) and Escherichia coli (E. coli) were the commonest bacterial pathogens. The annual rates of early-onset GBS meningitis decreased since the implementation of the universal GBS screening and intrapartum antibiotics prophylaxis (IAP) in 2012, while that of late-onset GBS meningitis remained similar. A significant portion of E. coli isolates were resistant to ampicillin and/or gentamicin.

CONCLUSION

GBS and E. coli remained the commonest bacteria for meningitis in this age group. The annual rate of bacterial meningitis in Hong Kong declined in recent years, which was attributed by the decline in that of early-onset GBS meningitis due to the universal GBS screening and IAP. Antimicrobial-resistant bacterial strains that caused meningitis require further clinical and public health attention.

Escherichia coli Causing Neonatal Meningitis During 2001-2020: A Study in Eastern China

Background and Objective

Neonatal meningitis (NM) caused by Escherichia coli remains a major health problem in industrialized countries. Currently, information on the epidemiology and antimicrobial susceptibility patterns of NM in developing countries such as China is relatively scarce. Therefore, the present study investigated changes in the antimicrobial susceptibility of E. coli causing NM in a perinatal center in eastern China over the past 20 years.

Methods

This survey was conducted during three periods: 2001–2006, 2007–2012, and 2013–2020. NM was diagnosed according to the number of white blood cells in the cerebrospinal fluid (CSF) and the presence of a single potential pathogenic bacterium in the culture prepared from the blood or CSF of a newborn baby. Changes in the antimicrobial susceptibility of E. coli were analyzed.

Results

In total, 182 NM cases were identified. E. coli was identified in 69 of these cases, and in 21 of these cases, extended-spectrum beta-lactamase (ESBL) production was detected. E. coli was the main cause of NM identified in this study. The overall susceptibility of E. coli to third-generation cephalosporins such as cefotaxime decreased from 100% during 2001–2006 to 50% during 2007–2012 and, subsequently, increased to 71.0% during 2013–2020. This pattern of change is correlated with bacterial ESBL production. Only 8.3% of E. coli found in samples collected from infants with early onset meningitis (EOM) produced ESBL, while 37.3% of E. coli isolated from children with late-onset meningitis (LOM) produced ESBL.

Conclusion

E. coli remains the primary pathogen of NM. Compared with that isolated from infants with LOM, the percentage of ESBL-producing multidrug-resistant E. coli isolated from infants with EOM is significantly lower. Clinicians should consider this trend when determining appropriate and effective antibiotics as empirical treatment for NM.

Characterization of the Blood and Cerebrospinal Fluid Microbiome in Children with Bacterial Meningitis and Its Potential Correlation with Inflammation

Bacterial meningitis shows a higher incidence in children than adults, but signs may be scarce. Although some pathogenic microorganisms of meningitis from cerebrospinal fluid (CSF) have been reported, the signature of the representative microbiota in CSF and blood samples from patients remains incompletely revealed. To extend the understanding of the microbiome in patients, we recruited 32 children with bacterial meningitis, 30 undiagnosed infectious children, and 10 matched healthy individuals, which was followed by untargeted metagenomic next-generation sequencing (mNGS) and bioinformatic analysis. Our results showed that children with bacterial meningitis exhibited different microbiome signatures in their CSF and blood compared with undiagnosed and healthy children, and patients could be divided into varied subsets according to these signatures, including Escherichia coli, Klebsiella pneumoniae, Thermothelomyces thermophila, Lactobacillus acidophilus, and Staphylococcus haemolyticus. To further explore their potential role in patients’ conditions, we examined their correlation with clinical parameters. Importantly, microbiome signatures with compositional changes were correlated with the C-reactive protein (CRP) level in blood and granulocyte percentage in CSF. Moreover, the blood in subsets of patients with a predominance of Klebsiella pneumoniae could replace CSF as the main specimen for clinical monitoring.

IMPORTANCE This study revealed the microbial compositions in children with bacterial meningitis who were treated with antibiotics and made a comprehensive comparison between blood and CSF specimens for the risk and prognosis assessment. We found that microbiome signatures could distinguish patient subsets in the children and were correlated with the CRP level in blood and granulocyte percentage in CSF. The compositional changes in representative microbiota constituents could provide guidance for clinical monitoring and antibiotic intervention.

Association of Infection in Neonates and Long-Term Neurodevelopmental Outcome

Perinatal and neonatal infection and associated inflammatory response may adversely affect brain development and lead to neurodevelopmental impairment. Factors that predict the risk of infection and subsequent adverse outcomes have been identified but substantial gaps remain in identifying mechanisms and interventions that can alter outcomes. This article describes the current epidemiology of neonatal sepsis, the pathogenesis of brain injury with sepsis, and the reported long-term neurodevelopment outcomes among survivors.

Etiology of acute meningitis and encephalitis from hospital-based surveillance in South Kazakhstan oblast, February 2017-January 2018

Encephalitis and meningitis (EM) are severe infections of the central nervous system associated with high morbidity and mortality. The etiology of EM in Kazakhstan is not clearly defined, so from February 1, 2017 to January 31, 2018 we conducted hospital-based syndromic surveillance for EM at the Shymkent City Hospital, in the South Kazakhstan region. All consenting inpatients meeting a standard case definition were enrolled. Blood and cerebrospinal fluid (CSF) samples were collected for bacterial culture, and CSF samples were additionally tested by PCR for four bacterial species and three viruses using a cascading algorithm. We enrolled 556 patients. Of these, 494 were of viral etiology (including 4 probable rabies cases), 37 were of bacterial etiology, 19 were of unknown etiology and 6 were not tested. The most commonly identified pathogens included enterovirus (73%, n = 406 cases), herpes simplex virus (12.8%, n = 71), and Neisseria meningitidis (3.8%, n = 21). The incidence rates (IRs) for enteroviral and meningococcal EM were found to be 14.5 and 0.7 per 100,000 persons, respectively. The IR for bacterial EM using both PCR and culture results was 3–5 times higher compared to culture-only results. Antibacterial medicines were used to treat 97.2% (480/494) of virus-associated EM. Incorporation of PCR into routine laboratory diagnostics of EM improves diagnosis, pathogen identification, ensures IRs are not underestimated, and can help avoid unnecessary antibacterial treatment.

An improved clinical prediction rule for identifying neonatal bacterial meningitis: a multicenter cohort study

BACKGROUND

To refine the bacterial meningitis (BM) score by improving its predictability of neonatal BM.

METHODS

A multicenter, ambispective cohort study was conducted in China, comprising 9 hospitals (retrospective cohort: January 2001 to December 2017; prospective cohort: January 2018 to August 2019). Of 3,504 eligible full-term neonates, 475 neonates with cerebrospinal fluid (CSF) pleocytosis were included. Based on the receiver operating characteristic (ROC) curve and logistic regression analyses, the BM score was refined by changing the thresholds of CSF protein level and the CSF absolute neutrophil count (ANC), and removing some variables (the peripheral blood ANC and a history of seizure before or at the time of presentation).

RESULTS

Of 475 neonates, 94 (19.8%) had BM. Based on the refined BM score, neonates with none of the following high-risk predictors were classified as being at very low risk for BM: CSF protein level ≥1,650 mg/L, CSF ANC ≥84×10⁶ cells/L, and positive CSF Gram stain result. The refined score showed 100% sensitivity in identifying BM and much higher specificity compared to that for the BM score (70.9% vs. 19.4%).

CONCLUSIONS

The refined BM score effectively identifies neonatal BM, and further studies are required to confirm our findings in prospective studies.

Roseville Protocol for the Management of Febrile Infants 7-60 Days

OBJECTIVES

The Roseville Protocol modifies the Rochester Protocol by adding a high-risk temperature criterion of >38.5°C for infants 7 to 28 days old and by allowing febrile infants 29 to 60 days old with abnormal urinalysis but reassuring complete blood cell counts to be discharged home on oral antibiotics without receiving a lumbar puncture (LP). In this study, we define the Roseville Protocol test characteristics to detect invasive bacterial infection (IBI) and retrospectively compare its performance to that of the Rochester, Philadelphia, and Boston protocols.

METHODS

In this retrospective study, we examine all cases of fever in infants aged 7 to 60 days presenting to a large health maintenance organization from 2007 to 2016 and having requisite laboratory tests for protocol analysis. The 4 protocols were retrospectively applied to this cohort to calculate each protocol's sensitivity and specificity to detect IBI. Protocols were compared regarding recommended LPs, admissions, and parenteral antibiotics.

RESULTS

In 627 infants 7 to 28 days old, the Roseville Protocol had a sensitivity of 96.7% and a negative predictive value of 99.5%. It identified 2 IBIs missed by the Rochester Protocol but recommended an absolute increase of 19% in LPs and admissions. In 1176 infants 29 to 60 days old, the Roseville Protocol had a sensitivity of 91.4% and a negative predictive value of 99.6%. There was an absolute reduction in LPs by 18% to 44% compared to the Rochester Protocol and by 74% to 100% compared to the Philadelphia and Boston protocols. There was an absolute reduction in admissions by 18% to 44% compared to the Rochester Protocol, by 25% to 51% compared to the Philadelphia Protocol, and by 10% to 36% compared to the Boston Protocol.

CONCLUSIONS

The Roseville Protocol has sensitivity and specificity comparable to that of existing protocols for IBI in febrile infants 7 to 60 days old, while allowing for fewer invasive procedures and hospitalizations in infants ≥29 days old.

TLR9 Rs352140 polymorphism contributes to a decreased risk of bacterial meningitis: evidence from a meta-analysis

Some studies have suggested that the Toll-like receptor 9 polymorphism (TLR9 rs352140) is closely related to the risk of bacterial meningitis (BM), but this is subject to controversy. This study set out to estimate whether the TLR9 rs352140 polymorphism confers an increased risk of BM. Relevant literature databases were searched including PubMed, Embase, the Cochrane Library and China National Knowledge Infrastructure (CNKI) up to August 2020. Seven case-control studies from four publications were enrolled in the present meta-analysis. Odds ratios (OR) and confidence intervals (95% CI) were calculated to estimate associations between BM risk and the target polymorphism. Significant associations identified were allele contrast (A vs. G: OR 0.66, 95% CI 0.59–0.75, P = 0.000), homozygote comparison (AA vs. AG/GG: OR 0.62, 95% CI 0.49–0.78, P = 0.000), heterozygote comparison (A vs. G: OR 0.74, 95% CI 0.61–0.91, P = 0.005), recessive genetic model (AA vs. AG/GG: OR 0.78, 95% CI 0.65–0.93, P = 0.006) and dominant genetic model (AA vs. AG/GG: OR 0.70, 95% CI 0.57–0.85, P = 0.000). The findings indicate that, in contrast to some studies, the TLR9 rs352140 polymorphism is associated with a decreased risk for BM.

Accuracy of MR Imaging for Detection of Sensorineural Hearing Loss in Infants with Bacterial Meningitis

BACKGROUND AND PURPOSE

Bacterial meningitis most commonly affects young children and can result in critical adverse outcomes, including sensorineural hearing loss (SNHL). The purpose of this study is to determine the diagnostic accuracy of MR imaging for predicting the development of SNHL among infants with bacterial meningitis.

MATERIALS AND METHODS

A retrospective review was performed among infants (age <365 days) with bacterial meningitis (n = 115). Independent and consensus blinded review of brain MRIs (n = 239) performed less than 90 days from presentation were conducted. Abnormal appearance of the inner ear was defined as enhancement on postcontrast T1-weighted (T1-weighted+C) sequence and FLAIR hyperintensity. The consensus MR imaging appearance of the inner ear on FLAIR, T1-weighted+C, and combined evaluation was compared with criterion standard audiometric testing to determine the sensitivity and specificity of MR imaging for detecting SNHL.

RESULTS

The mean age at diagnosis of bacterial meningitis was 50.6 days (range, 0-338 days) and 24.3% had SNHL. Sensitivity and specificity was 0.61/0.96, 0.50/0.94, and 0.61/0.94 for T1-weighted+C, FLAIR hyperintensity, and combined evaluation, respectively, for prediction of SNHL. There was excellent interobserver agreement for both the T1-weighted+C and FLAIR sequences and combined evaluation for presence of abnormal enhancement and hyperintense signal, respectively. Factors associated with abnormal MR imaging findings on T1-weighted+C and/or FLAIR in patients with SNHL included low CSF glucose (P = .04, .02) and high CSF protein (P = .04, .03).

CONCLUSIONS

Abnormal enhancement and/or FLAIR hyperintensity of the inner ear demonstrate high specificity and average sensitivity for prediction of SNHL among infants with bacterial meningitis.

Comparison of CSF and MRI Findings among Neonates and Infants with E coli or Group B Streptococcal Meningitis

BACKGROUND AND PURPOSE

Group B Streptococcus and Escherichia coli (E coli) are the 2 most common causes of bacterial meningitis in neonates. The purpose of this study was to determine whether CSF and/or MR imaging findings differ between infants with group B streptococcal or E coli meningitis.

MATERIALS AND METHODS

A retrospective review was performed among neonates (younger than 28 days) and infants (younger than 120 days) with proved group B streptococcal (n = 57) or E coli meningitis (n = 50). A CSF or blood culture positive for Streptococcus or E coli and an elevated CSF white blood cell count were used as the criterion standard. Independent, blinded review of brain MRIs obtained within 21 days of presentation were performed by 2 board-certified neuroradiologists. CSF laboratory values and MR imaging findings were compared between the groups.

RESULTS

There was no statistically significant difference between the mean age at presentation for patients with group B streptococcal (40 days; range, 2-111 days) versus patients with E coli meningitis (31 days; range, 12-115 days) (P = .18). There was no statistically significant difference in the CSF white blood cell count, glucose, or protein. There was a significant difference between group B streptococcal and E coli meningitis in the frequency of hydrocephalus (0% versus 22%, P = .001) and infarct (40% versus 14%; P = .038), respectively. There was no statistically significant difference in leptomeningeal enhancement, cerebritis, ventriculitis, abscess/granuloma, subdural effusion, extra-axial purulent material, intraventricular purulent material, hemorrhage, and sinus thrombosis.

CONCLUSIONS

Although neonates and infants with group B streptococcal or E coli meningitis had similar age and CSF laboratory values, patients with group B streptococcal meningitis more frequently demonstrated infarcts, while those with E coli meningitis more frequently had early onset of hydrocephalus.

Antigenic epitopes on the outer membrane protein A of Escherichia coli identified with single-chain variable fragment (scFv) antibodies

Bacterial meningitis is a severe disease that is fatal to one-third of patients. The major cause of meningitis in neonates is Escherichia coli (E. coli) K1. This bacterium synthesizes an outer membrane protein A (OmpA) that is responsible for the adhesion to (and invasion of) endothelial cells. Thus, the OmpA protein represents a potential target for developing diagnostic and therapeutic agents for meningitis. In this study, we expressed recombinant OmpA proteins with various molecular weights in E. coli. The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was performed to check the molecular size of OmpA's full length (FL) and truncated proteins. OmpA-FL protein was purified for immunizing chickens to produce immunoglobulin yolk (IgY) antibodies. We applied phage display technology to construct antibody libraries (OmpA-FL scFv-S 1.1 × 10⁷ and OmpA-FL scFv-L 5.01 × 10⁶) to select specific anti-OmpA-FL scFv antibodies; these were characterized by their binding ability to recombinant or endogenous OmpA using ELISA, immunofluorescent staining, and confirmed with immunoblotting. We found 12 monoclonal antibodies that react to OmpA fragments; seven scFvs recognize fragments spanning amino acid (aa) residues 1-346, aa 1-287, aa 1-167, and aa 60-192, while five scFvs recognize fragments spanning aa 1-346 and aa 1-287 only. Two fragments (aa 246-346 and aa 287-346) were not recognized with any of the 12 scFvs. Together, the data suggest three antigenic epitopes (60 aa-160 aa, 161 aa-167 aa, 193 aa-245 aa) recognized by monoclonal antibodies. These scFv antibodies show strong reactivity against OmpA proteins. We believe that antibodies show promising diagnostic agents for E. coli K1 meningitis.

Early onset sepsis calculator-based management of newborns exposed to maternal intrapartum fever: a cost benefit analysis

OBJECTIVE

To determine potential net monetary benefit of an early onset sepsis calculator-based approach for management of neonates exposed to maternal intrapartum fever, compared to existing guidelines.

STUDY DESIGN

We performed a cost-benefit analysis comparing two management approaches for newborns >34 weeks gestational age exposed to maternal intrapartum fever. Probabilities of sepsis and meningitis, consequences of infection and antibiotic use, direct medical costs, and indirect costs for long-term disability and mortality were considered.

RESULTS

A calculator-based approach resulted in a net monetary benefit of $3998 per infant with a 60% likelihood of net benefit in probabilistic sensitivity analysis. Our model predicted a 67% decrease in antibiotic use in the calculator arm. The absolute difference for all adverse clinical outcomes between approaches was ≤0.6%.

CONCLUSIONS

Compared to existing guidelines, a calculator-based approach for newborns exposed to maternal intrapartum fever yields a robust net monetary benefit, largely by preventing unnecessary antibiotic treatment.

Comparing Single vs. Combined Cerebrospinal Fluid Parameters for Diagnosing Full-Term Neonatal Bacterial Meningitis

Objectives: To identify and compare the cerebrospinal fluid (CSF) parameters that predict the presence of neonatal bacterial meningitis using optimal cutoff values, and to derive and compare predictive profiles based on a combination of individual parameters for the same purpose.

Study Design: The retrospective component of the Shanghai Neonate Meningitis Cohort included all term neonates who underwent lumbar puncture between 2000 and 2017. Those with severe neurological diseases, histories of ventricular drainage, or traumatic lumbar punctures were excluded. Reference ranges were determined for non-bacterial meningitis neonates based on the 5th, 25th, 50th, 75th, and 95th CSF parameter quantiles, and their relationships with age were calculated using generalized additive models that tested for linear relationships. The optimal cutoff value for each measured CSF parameter was calculated using receiver operating characteristic analysis and by deriving the Youden's index. Parameters with good diagnostic efficacies were combined to produce predictive profiles using logistic regression. The diagnostic efficacies of the single parameters and profiles were compared in neonates with confirmed bacterial meningitis.

Results: White blood cells (WBCs) in CSF showed a higher diagnostic ability for neonatal bacterial meningitis than CSF protein, glucose, lactate dehydrogenase, or chloride. The sensitivity and specificity of the diagnostic cutoff value for WBCs (20 × 10⁶/L) were 95.1 and 98.7%, respectively. Profiles based on CSF parameter combinations improved the specificities slightly to 99.0–99.7%. However, employing predictive profiles did not improve sensitivities, which remained at 95.1–96.0%.

Conclusions: Profiles for predicting neonatal bacterial meningitis improve the sensitivity and specificity of diagnosis slightly, although not appreciably, compared to the single parameter of CSF WBC alone.

Application of the Rochester Criteria to Identify Febrile Infants With Bacteremia and Meningitis

OBJECTIVES

The Rochester criteria were developed to identify febrile infants aged 60 days or younger at low-risk of bacterial infection and do not include cerebrospinal fluid (CSF) testing. Prior studies have not specifically assessed criteria performance for bacteremia and bacterial meningitis (invasive bacterial infection). Our objective was to determine the sensitivity of the Rochester criteria for detection of invasive bacterial infection.

METHODS

Retrospective cohort study of febrile infants aged 60 days or younger with invasive bacterial infections evaluated at 8 pediatric emergency departments from July 1, 2012, to June 30, 2014. Potential cases were identified from the Pediatric Health Information System using International Classification of Diseases, Ninth Revision diagnosis codes for bacteremia, meningitis, urinary tract infection, and fever. Medical record review was then performed to confirm presence of an invasive bacterial infection and to evaluate the Rochester criteria: medical history, symptoms or ill appearance, results of urinalysis, complete blood count, CSF testing (if obtained), and blood, urine, and CSF culture. An invasive bacterial infection was defined as growth of pathogenic bacteria from blood or CSF culture.

RESULTS

Among 82 febrile infants aged 60 days or younger with invasive bacterial infection, the sensitivity of the Rochester criteria were 92.7% (95% confidence interval [CI], 84.9%-96.6%) overall, 91.7% (95% CI, 80.5%-96.7%) for neonates 28 days or younger, and 94.1% (95% CI, 80.9%-98.4%) for infants aged 29 to 60 days old. Six infants with bacteremia, including 1 neonate with bacterial meningitis, met low-risk criteria.

CONCLUSIONS

The Rochester criteria identified 92% of infants aged 60 days or younger with invasive bacterial infection. However, 1 neonate 28 days or younger with meningitis was classified as low-risk.

Factors Associated with Adverse Outcomes among Febrile Young Infants with Invasive Bacterial Infections

OBJECTIVE

To determine factors associated with adverse outcomes among febrile young infants with invasive bacterial infections (IBIs) (ie, bacteremia and/or bacterial meningitis).

STUDY DESIGN

Multicenter, retrospective cohort study (July 2011-June 2016) of febrile infants ≤60 days of age with pathogenic bacterial growth in blood and/or cerebrospinal fluid. Subjects were identified by query of local microbiology laboratory and/or electronic medical record systems, and clinical data were extracted by medical record review. Mixed-effect logistic regression was employed to determine clinical factors associated with 30-day adverse outcomes, which were defined as death, neurologic sequelae, mechanical ventilation, or vasoactive medication receipt.

RESULTS

Three hundred fifty infants met inclusion criteria; 279 (79.7%) with bacteremia without meningitis and 71 (20.3%) with bacterial meningitis. Forty-two (12.0%) infants had a 30-day adverse outcome: 29 of 71 (40.8%) with bacterial meningitis vs 13 of 279 (4.7%) with bacteremia without meningitis (36.2% difference, 95% CI 25.1%-48.0%; P < .001). On adjusted analysis, bacterial meningitis (aOR 16.3, 95% CI 6.5-41.0; P < .001), prematurity (aOR 7.1, 95% CI 2.6-19.7; P < .001), and ill appearance (aOR 3.8, 95% CI 1.6-9.1; P = .002) were associated with adverse outcomes. Among infants who were born at term, not ill appearing, and had bacteremia without meningitis, only 2 of 184 (1.1%) had adverse outcomes, and there were no deaths.

CONCLUSIONS

Among febrile infants ≤60 days old with IBI, prematurity, ill appearance, and bacterial meningitis (vs bacteremia without meningitis) were associated with adverse outcomes. These factors can inform clinical decision-making for febrile young infants with IBI.

Predictors of Poor Outcome in Neonates with Pyogenic Meningitis in a Level-Three Neonatal Intensive Care Unit of Developing Country

BACKGROUND

The mortality of neonatal pyogenic meningitis is reduced to 10-15%, but morbidity is unchanged.

METHODS

Primary objective is to determine the outcome, i.e. death or abnormal neurological examination (NE) at discharge and abnormal developmental quotient (DQ) at 3 months. Secondary objective is to find predictors of poor outcome.

RESULTS

In all, 89 neonates enrolled, 10 expired and 24 neonates had abnormal NE at discharge. A total of 59 neonates came for follow up, 13 had DQ < 70. Prolonged shock (odds ratio, OR: 8.28; p = 0.001), coma (OR: 4.3; p = 0.001), seizures (OR: 14; p = 0.012), mechanical ventilation (OR: 18.55; p = 0.00), orogastric feeding (OR: 2.78; p = 0.042) and electroencephalography (EEG; OR: 9.6; p = 0.00) predicted poor short-term outcome. Abnormal NE at discharge (OR: 15.6; p = 0.001), EEG (OR = 10.60; p = 0.00) and brainstem-evoked reflex audiometry (OR = 37.20, p = 0.00) predicted a low DQ at 3 months. Mortality and morbidity of neonates with Pyogenic Meningitis (PM) were similar to that in developed countries. Outcome depended on severity of the disease and NE at discharge.

Pitfalls in the diagnosis of meningitis in neonates and young infants: the role of lumbar puncture

Meningitis occurs frequently in neonates and can lead to a number of acute, severe complications and long-term disabilities. An early diagnosis of neonatal meningitis is essential to reduce mortality and to improve outcomes. Initial clinical signs of meningitis are often subtle and frequently overlap with those of sepsis, and current haematologic tests do not distinguish sepsis from meningitis. Thus, lumbar puncture (LP) remains the gold standard for the diagnosis of meningitis in infants, and this procedure is recommended in clinical guidelines. Nevertheless, in clinical practice, LP is frequently deferred or omitted due to concerns regarding hypothetical adverse events or limited experience of the performer. Future studies should assess whether a combination of clinical findings and select haematologic tests at disease onset can identify those neonates with the highest risk of meningitis who should undergo LP. Furthermore, clinicians should be convinced that the actual benefits of an early diagnosis of meningitis far outweigh the hypothetical risks associated with LP.

Five-Year Multicenter Study of Clinical Tests of Neonatal Purulent Meningitis

This study aimed to provide more data support for early diagnosis and treatment of neonatal purulent meningitis through retrospective analysis of its clinical diagnosis and treatment, pathogen distribution, and drug resistance in 5 third-class A hospitals in Southwest and Northwest China from January 2011 to December 2015. It was found that both the positive rates of blood and cerebrospinal fluid culture were low, and Escherichia coli should be the main pathogenic bacteria. Drug-resistant strains with varying degrees to the third generation of cephalosporin antibiotics have appeared currently.

Human Meningitis-Associated Escherichia coli

Escherichia coli is the most common Gram-negative bacillary organism causing meningitis, and E. coli meningitis continues to be an important cause of mortality and morbidity throughout the world. Our incomplete knowledge of its pathogenesis contributes to such mortality and morbidity. Recent reports of E. coli strains producing CTX-M-type or TEM-type extended-spectrum β-lactamases create a challenge. Studies using in vitro and in vivo models of the blood-brain barrier have shown that E. coli meningitis follows a high degree of bacteremia and invasion of the blood-brain barrier. E. coli invasion of the blood-brain barrier, the essential step in the development of E. coli meningitis, requires specific microbial and host factors as well as microbe- and host-specific signaling molecules. Blockade of such microbial and host factors contributing to E. coli invasion of the blood-brain barrier is shown to be efficient in preventing E. coli penetration into the brain. The basis for requiring a high degree of bacteremia for E. coli penetration of the blood-brain barrier, however, remains unclear. Continued investigation on the microbial and host factors contributing to a high degree of bacteremia and E. coli invasion of the blood-brain barrier is likely to identify new targets for prevention and therapy of E. coli meningitis.

Escherichia coli K1 utilizes host macropinocytic pathways for invasion of brain microvascular endothelial cells

Eukaryotic cells utilize multiple endocytic pathways for specific uptake of ligands or molecules, and these pathways are commonly hijacked by pathogens to enable host cell invasion. Escherichia coli K1, a pathogenic bacterium that causes neonatal meningitis, invades the endothelium of the blood-brain barrier, but the entry route remains unclear. Here, we demonstrate that the bacteria trigger an actin-mediated uptake route, stimulating fluid phase uptake, membrane ruffling and macropinocytosis. The route of uptake requires intact lipid rafts as shown by cholesterol depletion. Using a variety of perturbants we demonstrate that small Rho GTPases and their downstream effectors have a significant effect on bacterial invasion. Furthermore, clathrin-mediated endocytosis appears to play an indirect role in E. coli K1 uptake. The data suggest that the bacteria effect a complex interplay between the Rho GTPases to increase their chances of uptake by macropinocytosis into human brain microvascular endothelial cells.

Assessment of healthcare delivery in the early management of bacterial meningitis in UK young infants: an observational study

OBJECTIVE

To define early presenting features of bacterial meningitis in young infants in England and to review the adequacy of individual case management as compared with relevant national guidelines and an expert panel review.

DESIGN

Retrospective medical case note review and parental recall using standardised questionnaires.

SETTING

England and Wales.

PARTICIPANTS

Infants aged <90 days with bacterial meningitis diagnosed between July 2010 and July 2013.

RESULTS

Of the 97 cases recruited across England and Wales, 66 (68%) were admitted from home and 31 (32%) were in hospital prior to disease onset. Almost all symptoms reported by parents appeared at the onset of the illness, with very few new symptoms appearing subsequently. Overall, 20/66 (30%) infants were assessed to have received inappropriate prehospital management. The median time from onset of first symptoms to first help was 5 hours (IQR: 2-12) and from triage to receipt of first antibiotic dose was 2.0 hours (IQR: 1.0-3.3), significantly shorter in infants with fever or seizures at presentation compared with those without (1.7 (IQR: 1.0-3.0) vs 4.2 (IQR: 1.8-6.3) hours, p=0.02). Overall, 26 (39%) infants had a poor outcome in terms of death or neurological complication; seizures at presentation was the only significant independent risk factor (OR, 7.9; 95% CI 2.3 to 207.0). For cases in hospital already, the median time from onset to first dose of antibiotics was 2.6 (IQR: 1.3-9.8) hours, and 12/31 (39%) of infants had serious neurological sequelae at hospital discharge. Hearing test was not performed in 23% and when performed delayed by ≥4 weeks in 41%.

CONCLUSIONS

In young infants, the non-specific features associated with bacterial meningitis appear to show no progression from onset to admission, whereas there were small but significant differences in the proportion of infants with more specific symptoms at hospital admission compared with at the onset of the illness, highlighting the difficulties in early recognition by parents and healthcare professionals alike. A substantial proportion of infants received inappropriate prehospital and posthospital management. We propose a targeted campaign for education and harmonisation of practice with evidence-based management algorithms.

Guiding Empiric Treatment for Serious Bacterial Infections via Point of Care [Formula: see text]-Lactamase Characterization

Fever is one of the most common symptoms of illness in infants and represents a clinical challenge due to the potential for serious bacterial infection. As delayed treatment for these infections has been correlated with increased morbidity and mortality, broad-spectrum [Formula: see text]-lactam antibiotics are often prescribed while waiting for microbiological lab results (1-3 days). However, the spread of antibiotic resistance via the [Formula: see text]-lactamase enzyme, which can destroy [Formula: see text]-lactam antibiotics, has confounded this paradigm; empiric antibiotic regimens are increasingly unable to cover all potential bacterial pathogens, leaving some infants effectively untreated until the pathogen is characterized. This can lead to lifelong sequela or death. Here, we introduce a fluorescent, microfluidic assay that can characterize [Formula: see text]-lactamase derived antibiotic susceptibility in 20 min with a sensitivity suitable for direct human specimens. The protocol is extensible, and the antibiotic spectrum investigated can be feasibly adapted for the pathogens of regional relevance. This new assay fills an important need by providing the clinician with hitherto unavailable point of care information for treatment guidance in an inexpensive and simple diagnostic format.

Ending preventable maternal and newborn deaths due to infection

Over 300,000 maternal deaths occur each year, 11% of which are thought to be due to infectious causes, and approximately one million newborns die within the first week of life annually due to infectious causes. Infections in pregnancy may result in a variety of adverse obstetrical outcomes, including preterm delivery, pre-labor rupture of membranes, stillbirth, spontaneous abortion, congenital infection, and anomalies. This paper reviews the burden of disease due to key infections and their contribution to maternal, perinatal, and newborn morbidity and mortality, as well as key interventions to prevent maternal and newborn deaths related to these infections. Research needs include more accurate clinical and microbiologic surveillance systems, validated risk stratification strategies, better point-of-care testing, and identification of promising vaccine strategies.

Bird's Eye View of a Neonatologist: Clinical Approach to Emergency Neonatal Infection

Though the incidence of neonatal infection in term and near-term infants is relatively low, incidence of infection in preterm very low birth weight infants is as high as 20-30% and may result in neurodevelopmental impairment or mortality. Pediatricians should be familiar with recognition and emergency management of life-threatening neonatal infections, such as congenital pneumonia, early onset sepsis, late onset sepsis, bacterial and fungal meningitis, disseminated neonatal herpes simplex virus (HSV), and HSV meningoencephalitis. For the pediatrician, it is logical to approach the management of these infections by time of onset, i.e., early versus late onset of infection. Perinatal risk factors and simple laboratory tests, such as total white blood-cell count, immature/total ratio, and C-reactive protein are helpful in guiding the decision of antibiotics therapy. Successful management of these critical infections depends upon early diagnosis and timely administration of adequate antibiotics. Empiric antibiotic therapy must cover the most likely pathogens according to the risk factors of each individual neonate, and therapy duration is dependent upon culture results, clinical course, and the microorganism. Future research may focus on developing a practical neonatal sepsis score system based on risk factors and common biomarkers, which are readily available at bedside to make early accurate decisions and achieve better outcomes.

Neonatal Emergencies

Newborns may present with vague signs and symptoms that result from a large variety of aetiologies.

Clinical Prognosis in Neonatal Bacterial Meningitis: The Role of Cerebrospinal Fluid Protein

Neonates are at high risk of meningitis and of resulting neurologic complications. Early recognition of neonates at risk of poor prognosis would be helpful in providing timely management. From January 2008 to June 2014, we enrolled 232 term neonates with bacterial meningitis admitted to 3 neonatology departments in Shanghai, China. The clinical status on the day of discharge from these hospitals or at a postnatal age of 2.5 to 3 months was evaluated using the Glasgow Outcome Scale (GOS). Patients were classified into two outcome groups: good (167 cases, 72.0%, GOS = 5) or poor (65 cases, 28.0%, GOS = 1–4). Neonates with good outcome had less frequent apnea, drowsiness, poor feeding, bulging fontanelle, irritability and more severe jaundice compared to neonates with poor outcome. The good outcome group also had less pneumonia than the poor outcome group. Besides, there were statistically significant differences in hemoglobin, mean platelet volume, platelet distribution width, C-reaction protein, procalcitonin, cerebrospinal fluid (CSF) glucose and CSF protein. Multivariate logistic regression analyses suggested that poor feeding, pneumonia and CSF protein were the predictors of poor outcome. CSF protein content was significantly higher in patients with poor outcome. The best cut-offs for predicting poor outcome were 1,880 mg/L in CSF protein concentration (sensitivity 70.8%, specificity 86.2%). After 2 weeks of treatment, CSF protein remained higher in the poor outcome group. High CSF protein concentration may prognosticate poor outcome in neonates with bacterial meningitis.

The molecular characterisation of Escherichia coli K1 isolated from neonatal nasogastric feeding tubes

BACKGROUND

The most common cause of Gram-negative bacterial neonatal meningitis is E. coli K1. It has a mortality rate of 10-15 %, and neurological sequelae in 30-50 % of cases. Infections can be attributable to nosocomial sources, however the pre-colonisation of enteral feeding tubes has not been considered as a specific risk factor.

METHODS

Thirty E. coli strains, which had been isolated in an earlier study, from the residual lumen liquid and biofilms of neonatal nasogastric feeding tubes were genotyped using pulsed-field gel electrophoresis, and 7-loci multilocus sequence typing. Potential pathogenicity and biofilm associated traits were determined using specific PCR probes, genome analysis, and in vitro tissue culture assays.

RESULTS

The E. coli strains clustered into five pulsotypes, which were genotyped as sequence types (ST) 95, 73, 127, 394 and 2076 (Achman scheme). The extra-intestinal pathogenic E. coli (ExPEC) phylogenetic group B2 ST95 serotype O1:K1:NM strains had been isolated over a 2 week period from 11 neonates who were on different feeding regimes. The E. coli K1 ST95 strains encoded for various virulence traits associated with neonatal meningitis and extracellular matrix formation. These strains attached and invaded intestinal, and both human and rat brain cell lines, and persisted for 48 h in U937 macrophages. E. coli STs 73, 394 and 2076 also persisted in macrophages and invaded Caco-2 and human brain cells, but only ST394 invaded rat brain cells. E. coli ST127 was notable as it did not invade any cell lines.

CONCLUSIONS

Routes by which E. coli K1 can be disseminated within a neonatal intensive care unit are uncertain, however the colonisation of neonatal enteral feeding tubes may be one reservoir source which could constitute a serious health risk to neonates following ingestion.

A population-based prospective birth cohort study of childhood neurocognitive and psychological functioning in healthy survivors of early life meningitis

PURPOSE

To determine neurocognitive, educational, and psychological functioning during childhood and early adolescence among survivors of early life meningitis who are apparently healthy.

METHODS

In the general population-based Avon Longitudinal Study of Parents and Children birth cohort, meningitis exposure was determined at age of 18 months. The outcomes of intelligence quotient, short-term memory, working memory, reading and spelling abilities, psychological and behavioral problems, depressive and anxiety symptoms, and psychotic experiences at ages 9 to 13 years were compared between those exposed and unexposed to meningitis. Individuals with special educational needs were excluded.

RESULTS

By age of 18 months, 67 of 11,035 children were reported to have suffered from meningitis (0.61%). These children, compared with the unexposed, performed worse on all neurocognitive and educational measures; mean difference in total intelligence quotient 7.36 (95% confidence interval, 1.60-13.11). Meningitis was associated with higher depressive and anxiety symptoms (P = .02), psychological and behavioral problems (P = .09), and increased risk of psychotic experiences; risk ratio 2.22 (95% confidence interval, 1.12-4.38).

CONCLUSIONS

Exposure to meningitis in the early life is associated with neurocognitive, educational, and psychological difficulties during childhood and early adolescence among survivors who are apparently healthy. Therefore, focusing only on serious neurologic disabilities may underestimate the true impact of early life meningitis.

Pathophysiology of neonatal acute bacterial meningitis

Neonatal meningitis is a severe acute infectious disease of the central nervous system and an important cause of morbidity and mortality worldwide. The inflammatory reaction involves the meninges, the subarachnoid space and the brain parenchymal vessels and contributes to neuronal injury. Neonatal meningitis leads to deafness, blindness, cerebral palsy, seizures, hydrocephalus or cognitive impairment in approximately 25-50 % of survivors. Bacterial pathogens can reach the blood-brain barrier and be recognized by antigen-presenting cells through the binding of Toll-like receptors. They induce the activation of NFκB or mitogen-activated protein kinase pathways and subsequently upregulate leukocyte populations and express numerous proteins involved in inflammation and the immune response. Many brain cells can produce cytokines, chemokines and other pro-inflammatory molecules in response to bacterial stimuli, and polymorphonuclear leukocytes are attracted, activated and released in large amounts of superoxide anion and nitric oxide, leading to peroxynitrite formation and generating oxidative stress. This cascade leads to lipid peroxidation, mitochondrial damage and breakdown of the blood-brain barrier, thus contributing to cell injury during neonatal meningitis. This review summarizes information on the pathophysiology and adjuvant treatment of acute bacterial meningitis in neonates.

The Expression of Interleukin-1b and miRNA-146a in the Cerebral Cortex of Acute Escherichia Coli Meningitis Immature Rat Model

The main limitation to advances in treatment of bacterial meningitis and its complications is the incomplete knowledge of the pathogenesis and pathophysiology of this disease. The aim of this research is to detect the expression of interleukin (IL)-1β as pro-inflammatory cytokine and miRNA (miR)-146a as post transcriptional inflammation associated microRNA (miRNA) in the cerebral cortex of acute Escherichia coli (E. coli) meningitis immature rat model. Immature rats in the post natal day 11 (PN11) were used to construct a model of acute E. coli meningitis and served as controls. The expression of IL-1β and miR-146a were detected in the cerebral cortex by reverse transcription polymerase chain reaction (RT-PCR) and real-time quantitative PCR (qPCR) analysis respectively, 24 hours after bacterial inoculation. In the cerebral cortical tissue of acute E. coli meningitis immature rat model the IL-1β expression was significantly upregulated while the miR-146a expression was significantly downregulated. This study tried to add a new insight on the molecular basis of the E. coli meningitis pathogenesis at its very early stage through detecting the expression of IL-1β and miR-146a in the cerebral cortex of the infected immature rats. Consequently, modulation of the IL-1β- miR-146a axis may be a new target for treatment of acute E. coli meningitis.

Immunochromatographic detection of the group B streptococcus antigen from enrichment cultures

Group B Streptococcus (GBS; Streptococcus agalactiae) is a leading cause of serious neonatal infections. The Centers for Disease Control and Prevention recommends GBS screening for all pregnant women during the 35th to 37th weeks of gestation. Although GBS screening has been performed mainly by the culture-based method, it takes several days to obtain a reliable result. In this study, we developed a rapid immunochromatographic test (ICT) for the detection of GBS-specific surface immunogenic protein in 15 min using an overnight enrichment culture. The ICT was prepared using two anti-Sip monoclonal antibodies. This ICT was able to detect recombinant Sip levels of 0.5 ng/ml, or about 10(6) CFU/ml of GBS cells, in tests with 9 GBS strains of different serotypes. The cross-reactivity test using 26 species of microorganism showed no detectable false-positive result. Reactivity of the ICT with 229 GBS strains showed one false-negative result that was attributable to the production of truncated Sip. Among 260 enrichment cultures of vaginal swabs, 17 produced red to orange pigments in Granada medium, and they were all GBS and Sip positive. Among 219 pigment-negative cultures, 12 were GBS positive and 10 were Sip positive. Two Sip-negative cultures contained GBS cells below the limit of detection by the ICT. Among 207 GBS-negative cultures, only one was Sip positive, which was attributable to GBS cell debris. Thus, the sensitivity and specificity of the ICT appeared to be 93.1% and 99.6%, respectively. The newly developed ICT is readily applicable to clinical use in the detection of GBS.

[Clinical outcome and prognosis of neonatal bacterial meningitis]

OBJECTIVES

To study the epidemiological, clinical, and bacteriological aspects as well as the outcome of neonatal bacterial meningitis and analyze the factors of poor prognosis of this condition.

PATIENTS AND METHODS

We report a retrospective analysis of 44 cases of neonatal bacterial meningitis hospitalized in the pediatric unit of Tahar Sfar Hospital in Mahdia, Tunisia, between January 1996 and December 2010. Inclusion criteria were infants less than 29 days of age who were hospitalized for bacterial meningitis diagnosed on either the presence of bacteria in cerebrospinal fluid or with more than 50 cells/mm(3), predominance of neutrophils, and the protein level greater than 1.2g/l. Clinical data were obtained through the analysis of patient files. Statistical analysis was based on the Chi(2) test, and P-values less than 0.05 were considered statistically significant.

RESULTS

The incidence of neonatal bacterial meningitis was 0.49 per 1000 live births. The patients were premature in 20.4 % and low birth weight in 13.6 % of cases. The clinical presentation was not specific for most cases. The main signs at admission were hyperthermia (43.2 %), refusal to nurse (20.4 %), seizures (18.2 %), and respiratory distress (13.6 %). The cerebrospinal fluid culture was positive in 36.4 % of cases. The group B streptococcus was the most frequently isolated (62.5 %) followed by Escherichia coli (12.5 %). The association of cefotaxime-ampicillin-gentamicin was used as the first treatment in all cases. Ofloxacin was associated with initial antibiotic therapy during the first 5 days in 20.4 % of cases. The mortality rate was 15.9 % and the rate of neurological sequelae in survivors was 21.6 %. Prematurity, low birth weight, shock, respiratory distress, and pleocytosis of less than 500 cells/mm(3) were the main factors of a poor prognosis. The addition of ofloxacin to the initial antibiotic therapy was associated with a decreased rate of neurological sequelae in survivors (11 % vs. 25 %, P=0.042).

CONCLUSION

This study emphasizes the severity of neonatal bacterial meningitis with high rates of mortality and neurological sequelae, especially in premature and low birth weight infants. An early diagnosis and effective antibiotic therapy is needed to improve the prognosis.

Preventing the broad spectrum of perinatal morbidity and mortality through group B streptococcal vaccination

The development of a group B streptococcal (GBS) glycoconjugate vaccine and its upcoming evaluation in a phase 3 trial in pregnant women highlight the importance of defining the anticipated impact of GBS vaccination upon the broad spectrum of GBS-related perinatal morbidity and mortality. We present the specific pregnancy-associated and neonatal conditions attributable, at least in part, to GBS in high and lower income countries. We offer a rationale to support our contention that implementation of GBS glycoconjugate immunization during pregnancy will reduce the global burden of GBS-related morbidity and mortality in pregnant women and their infants.

Long-term outcomes of group B streptococcal meningitis

OBJECTIVE

Group B Streptococcus (GBS) is the leading cause of meningitis in young infants. We evaluated long-term outcomes among GBS meningitis survivors. We hypothesized that despite reduced mortality, GBS meningitis would remain a significant cause of morbidity among GBS survivors.

METHODS

Ninety term and near-term infants diagnosed with GBS meningitis from 1998 through 2006 were identified from 2 children's hospitals. Five died acutely, and 5 died at 6 months to 3 years of age. Forty-three survivors (54%; mean age 6.8, range 3-12 years) were consented for evaluation and underwent physical and neurologic examinations, hearing and vision screening, and standardized developmental assessments. Associations among presenting features, laboratory parameters, neurologic status at hospital discharge, and later developmental outcomes were explored by using descriptive statistics and logistic regression.

RESULTS

Twenty-four of 43 (56%) children evaluated demonstrated age-appropriate development, 11 (25%) had mild-to-moderate impairment, and 8 (19%) had severe impairment. Admission features associated with death after hospital discharge or severe impairment included lethargy (P = .003), respiratory distress (P = .022), coma or semicoma (P = .022), seizures (P = .015), bulging fontanel (P = .034), leukopenia (P = .026), acidosis (P = .024), cerebrospinal fluid protein >300 mg/dL (P = .006), cerebrospinal fluid glucose <20 mg/dL (P = .026), and need for ventilator (P = .002) or pressor support (P < .001). Features at discharge associated with late death or severe impairment included failed hearing screen (P = .004), abnormal neurologic examination (P < .001), and abnormal end of therapy brain imaging (P = .038).

CONCLUSIONS

Survivors of GBS meningitis continue to have substantial long-term morbidity, highlighting the need for ongoing developmental follow-up and prevention strategies such as maternal immunization.