Acute bacterial meningitis

Procalcitonin contributes to hippocampal neuronal damage and impairment of LTP: implications for cognitive dysfunction in LPS-induced neuroinflammation rat model

Bacterial meningitis (BM) can lead to cognitive impairment, seriously affecting patients' quality of life. Our previous study demonstrated a significant increase in procalcitonin (PCT) levels in cerebrospinal fluid (CSF) in BM patients, but the functional implications remain unknown. We found high expression of PCT in the hippocampus of LPS-induced neuroinflammation models. PCT had a neurotoxic effect on the primarily cultured hippocampal neurons. The high dose of PCT induced neuronal apoptosis. The low dose of PCT impaired the arborization of hippocampal neurons and reduced the expression of the growth-associated protein-43 (GAP-43) and synaptophysin (SYN). Furthermore, long-term potentiation (LTP) in hippocampal brain slices was decreased after PCT perfusion ex vivo. Our results indicated that PCT had neurotoxic effects on neuronal survival and synaptic plasticity, potentially leading to cognitive impairment after BM.

Pneumococcal Meningovasculitis: A Deadly Foe

Meningitis is an inflammation of the protective membranes surrounding the brain and spinal cord, typically caused by viral or bacterial infections. Bacterial meningitis is a medical emergency requiring prompt diagnosis and treatment, which is associated with a significant mortality rate, even with optimal care. We report the case of a previously healthy 57-year-old man who presented to the emergency department with a three-week history of fever, dry cough, myalgia, fatigue, weakness, anorexia, and excessive sweating. Physical examination revealed a tympanic temperature of 38.9ºC, leukocytosis with neutrophilia, and elevated C-reactive protein levels. A computed tomography (CT) scan of the chest, abdomen, and pelvis showed consolidations in the left lung with air bronchograms and ground-glass opacities. His condition rapidly deteriorated with progressively higher fever, neck stiffness, positive Kernig and Brudzinski signs, profuse sweating, and altered mental status with a Glasgow Coma Scale (GCS) of 8, requiring non-invasive ventilation. He was thus admitted to the intensive care unit (ICU) on the second day of hospitalization. Lumbar puncture confirmed Streptococcus pneumoniae in the cerebrospinal fluid culture, supporting the diagnosis of pneumococcal meningitis. Electroencephalogram (EEG) findings were consistent with severe encephalopathy, while a follow-up CT scan revealed bilateral temporal hypodensities extending into the brainstem, suggestive of ischemic lesions of a vasculitic nature. Magnetic resonance imaging (MRI) confirmed multiple acute ischemic lesions throughout the brain and brainstem, along with signs of leptomeningitis and purulent collections in the lateral ventricles. Despite receiving 14 days of antibiotic therapy and intensive medical efforts, the patient showed no clinical improvement and ultimately succumbed to the infection. This case highlights the critical importance of early recognition and diagnosis of meningitis, as delayed treatment can lead to devastating outcomes. Continuous monitoring and a low threshold of suspicion are key elements for preventing fulminant central nervous system infections.

Investigating Blood Biomarkers That Can Facilitate the Diagnosis of Meningitis-A Systematic Literature Review

Meningitis is an inflammation of the meninges that can sometimes be a life-threatening disease. Therefore, fast and proper diagnosis with the implementation of adequate treatment is crucial in its management. Treatment depends on etiology, which can be viral, bacterial, fungal, and parasitic. Diagnosis is based on thorough clinical examination with a performance of lumbar puncture in the case of meningitis suspicion. This procedure, however, remains invasive with several contraindications and a need for a patient's consent, which is not always given due to the patient's fear of it, for instance. Thus, this systematic review aimed to summarize the available literature on the topic of blood biomarkers in meningitis differentiation. A selection process was performed by two authors independently in accordance with the Preferred Research Items for Systematic Reviews and Meta-analyses. Two databases were screened. It led to the identification of 863 articles, of which 43 were eventually included in the systematic review. The analysis resulted in identifying blood biomarkers in both adult and pediatric meningitis. Most studies focused on inflammatory markers, such as C-reactive protein and procalcitonin, from which procalcitonin showed better utility. Among other analyzed molecules were, for instance, interleukins, apolipoproteins, and microRNAs. Moreover, many researchers suggested that combining biomarkers or implementing novel technologies may lead to the best accuracy. However, many suggested methods lack validation, which stands in the way of making them widely used.

Unraveling the interplay between meningitis and mitochondria: Etiology, pathogenesis, and therapeutic insights

Meningitis, characterized by an inflammatory response affecting the membranes surrounding the brain and spinal cord, poses a formidable challenge to global public health. Its etiology spans a spectrum of infectious agents, ranging from bacteria, to viruses, fungi, and parasites. Concurrently, mitochondria-traditionally known as 'cellular powerhouses'-have emerged as critical players in various essential biological functions, including but not limited to, energy production, metabolic regulation, and cell fate determination. Emerging evidence suggests that mitochondria may play vital roles in the pathogenesis of meningitis. In this review, we delineated the definition, classification, etiology, pathogenesis, and clinical manifestations of meningitis, and elucidated the structure, dynamics and functions of mitochondria. We subsequently delved into the intricate interplay between meningitis and mitochondria, identifying potential therapeutic interventions targeting mitochondria for the first time. With clinical trials on the horizon, our review lays the foundation for a transformative era in meningitis therapeutics, where unraveling the intricate interplay between meningitis and mitochondria offers promise for mitigating neuroinflammation and improving patient outcomes.

Management and prevention of Neisseria meningitidis and Neisseria gonorrhoeae infections in the context of evolving antimicrobial resistance trends

PURPOSE

To describe the relationships between Neisseria meningitidis (NM) and Neisseria gonorrhoeae (NG) at genetic, population, and individual levels; to review historical trends in antimicrobial resistance (AMR); to review the treatment and preventive landscapes and explore their potential impact on AMR.

METHODS

A narrative literature search was conducted in PubMed, with searches restricted to 2003-2023 and additional articles included based on expertise.

RESULTS

NM and NG are closely related bacterial pathogens causing invasive meningococcal disease (IMD) and gonorrhea, respectively. NM can currently be treated with most antibiotics and generally has a wild-type susceptibility profile, whereas NG is increasingly resistant even in the first line of treatment. These pathogens share 80-90% genetic identity and can asymptomatically cohabit the pharynx. While AMR has historically been rare for NM, recent reports show this to be an emerging clinical concern. Extensively drug-resistant NG are reported globally, with data available from 73 countries, and can lead to treatment failure. Importantly, Neisseria commensals within the normal microbiota in the pharynx can act as a genetic reservoir of resistance to extended-spectrum cephalosporins. Novel oral antibiotics are urgently needed to treat a growing threat from antibiotic-resistant NG, recognized as a major global concern to public health by the World Health Organization. Numerous vaccines are available to prevent IMD, but none are approved for gonorrhea. Research to identify suitable candidates is ongoing.

CONCLUSION

Holistic management of AMR in IMD and gonorrhea should couple judicious use of existing antibiotics, optimization of vaccination programs, and development of novel antibiotics and vaccines.

Streptococcus suis-associated neonatal meningitis and sepsis: characterization, antimicrobial resistance, and public health implications

Neonatal meningitis and sepsis were diagnosed in a 32-day-old preterm-born infant. Streptococcus (S.) suis was isolated from cerebrospinal fluid and blood. Next-generation sequencing revealed that the strain was serotype 2 sequence type 1, and contained the ermB and tet(W) genes, which are responsible for resistance to macrolides and tetracycline, along with several pilus-associated genes and 20 virulence factors. High homology was observed with previously identified human and swine strains in the same area. S. suis meningitis and sepsis are mainly reported in adults, related to direct contact with pigs or contaminated pork meat consumption, while it is rarely reported in children. Herein, we describe the first case of S. suis in a newborn associated with meningitis and antimicrobial resistance. The rates of resistance to tetracyclines, lincosamides, and macrolides for this bacterium are increasing and are creating concern worldwide. Altogether, our findings highlight the importance of investigating S. suis in cases of neonatal meningitis, as well as the necessity of assessing the antimicrobial profile to obtain useful information for developing targeted therapies.

Interactions of the Pneumococcus with the Central Nervous System: Postnatal Meningitis Versus Fetal Neurodevelopment

In young children, pneumococcal meningitis epitomizes the paradigm of a destructive innate inflammatory response in the central nervous system: a five-alarm fire. In contrast, cell-free bacterial components reaching the fetal brain from an infected mother signal a quiet, noninflammatory immune response that drives abnormal neurodevelopment, changing brain architecture through neuroproliferation. This review addresses the difference between prenatal and postnatal bacterial-host signaling within the brain.

Risk of psychiatric neurodevelopmental disorders after meningitis in childhood: a nationwide, population-based cohort study

BACKGROUND

Few studies have investigated the risk of psychiatric neurodevelopmental disorders (PNDD) after childhood meningitis.

METHODS

Nationwide population-based cohort study (Denmark, 1995-2021) of children with positive cerebrospinal fluid for bacteria or enterovirus, stratified on age as young infants (0 to <90 days, n = 637) or older children (≥90 days to <17 years, n = 1,218). We constructed a comparison cohort from the general population (n = 18,550), and cohorts of siblings of participants. As risk estimates of PNDD we calculated age- and sex-adjusted hazard ratios (aHRs) with 95% confidence intervals (95%CI).

RESULTS

Children with bacterial meningitis had increased risks of PNDD, especially learning and intellectual developmental disorders (young infants: aHR 4.2, 95%CI: 2.4-7.1; older children: aHR 1.5, 95%CI: 1.0-2.3), attention deficit disorder (ADHD) (young infants: aHR 2.8, 95%CI: 1.5-5.2; older children: 1.4, 95%CI: 0.9-2.2) and redemption of ADHD medication (young infants: aHR 2.2, 95%CI: 1.0-4.7; older children: 1.5, 95%CI: 1.0-2.3). Young infants with bacterial meningitis additionally had increased risks of autism spectrum disorders (aHR 1.9, 95%CI: 0.9-4.1) and behavioural and emotional disorders (aHR 2.0, 95%CI: 1.0-3.9). In young infants, the excess risk of PNDD was especially observed in premature children. Siblings of older children with bacterial meningitis also had increased risks of PNDD. Children with enteroviral meningitis at any age did not have increased risks of PNDD or redemption of ADHD medication.

CONCLUSIONS

Bacterial meningitis in childhood is associated with subsequent diagnosis of PNDD, while enteroviral meningitis is not. The association appears to be partly explained by prematurity and familial and socioeconomic factors.

Factors Associated with In-Hospital Mortality in Adult Patients with Bacterial Meningitis

Background/Objectives: The aim of this study was to evaluate the association between various clinical and laboratory findings and in-hospital mortality in community-acquired bacterial meningitis (BM). Methods: We retrospectively analyzed 339 adult (≥18 years old) patients with bacterial meningitis who were admitted to the Hospital for Infectious Diseases in Warsaw between January 2010 and December 2017. Results: Altogether, 56 patients (16.5%) died during hospitalization. On admission, the non-survivors scored lower on the Glasgow Coma Scale (GCS) (median 7 vs. 13, p < 0.001) and higher on the Sequential Organ Failure Assessment (SOFA) score (median 6 vs. 2, p < 0.001) and were less likely to complain about headaches (18.75% vs. 54.21%, p < 0.001) and nausea and/or vomiting (1.89% vs. 36.2%, p < 0.001), but were more likely to manifest peripheral nerve palsies (21.43% vs. 9.61%, p = 0.02). The patients who died were also more likely to be immunocompromised (53.57% vs. 34.28%, p = 0.01), have Streptococcus pneumoniae etiology (35.71% vs. 16.25%, p = 0.001), higher concentrations of procalcitonin (median 5.035 ng/mL vs. 2.245 ng/mL, p = 0.003) and urea (median 10.7 mmol/L vs. 5.865 mmol/L, p < 0.001) in the blood and higher protein (median 4.57 g/L vs. 2.605 g/L, p = 0.014) and lower glucose levels (median 0.765 mmol/L vs. 1.89 mmol/L, p = 0.006) in the cerebrospinal fluid (CSF). In a multiple logistic regression analysis, which was conducted separately for the GCS and SOFA, both scoring systems (OR = 0.67, OR 95% CI 0.59-0.75, p < 0.001 for GCS and OR = 1.42, OR 95% CI 1.29-1.60, p < 0.001 for SOFA) as well as an age over 70 years (OR = 3.99, OR 95% CI 1.39-12.93, p = 0.014) and Streptococcus pneumoniae etiology (OR = 2.38, OR 95% CI 1.12-4.99, p = 0.022) were associated with in-hospital deaths. Conclusions: The survivors and non-survivors with BM differed with respect to a number of signs and symptoms, etiology, the results of blood and CSF laboratory tests, and the immune deficiency status, as well as the GCS and SOFA scores. In the multiple logistic regression analysis, both of the GCS and SOFA scoring systems, age and Streptococcus pneumoniae etiology showed high associations with the in-hospital deaths.

Case report: an infant with late-onset meningitis caused by Escherichia coli

Background

Meningitis is highly prevalent in infant because their immune system is immature and they have less resistance to diseases. Among bacterial agents, Escherichia coli is recognized as one of the most important causes of meningitis in infants.

Case presentation

Herein, we report a case of late-onset meningitis, caused by E. coli (Patient:17-day-old female infant). The patient's body temperature was 39°C, and the initial diagnosis was sepsis. At the doctor's request, the patient underwent the basic tests and was hospitalized in the Neonatal Intensive Care Unit (NICU). In this case, blood culture and CSF culture were negative and positive, respectively. Echogenic particles were observed inside the bladder, indicating possible cystitis. The results of the antibiotic susceptibility tests showed that the meningitis-causing strain of E. coli was susceptible only to amikacin.

Conclusion

Conducting LP and CSF culture seems to be the most important strategy for diagnosing meningitis. It is also recommended to perform LP before taking antibiotics. For identifying the infection, some factors such as fever, CRP test results, CSF parameters (leukocyte count, glucose level, and CSF culture results) should be considered to prevent misdiagnosis.

Clinical value of heparin-binding protein in adult bacterial intracranial infection

Background

The accurate and sensitive diagnosis of intracranial infection continues to pose a critical challenge. This study aimed to probe into the clinical value of heparin binding protein (HBP) in bacterial intracranial infection.

Methods

Patients suspected of having bacterial intracranial infection and admitted to Shanghai General Hospital from November 2021 to November 2023 were selected as study subjects and divided into an infected group and a non-infected group. The receiver operating characteristic (ROC) curve was constructed to compare the diagnostic accuracy of HBP, procalcitonin (PCT), and C-reactive protein (CRP), as well as their value in differentiating Gram-positive bacteria and Gram-negative bacterial infections.

Results

According to the results of bacterial identification, the infected groups were divided into a Gram-negative bacteria group (n = 142) and a Gram-positive bacteria group (n = 128), while the non-infected group comprised 120 patients after neurosurgery involving dura opening. Statistically significant differences were observed in the levels of HBP, PCT, and CRP between the infected group and the non-infected group (all p< 0.05). Receiver operating characteristic (ROC) curve analysis showed that the area under the curve (AUC) of HBP was 0.935, and the AUCs of PCT and CRP were 0.931 and 0.863, respectively. In the comparison of HBP, PCT, and CRP levels in the Gram-negative bacteria and Gram-positive bacteria groups, the AUCs were 0.816, 0.602, and 0.591, respectively. When the cutoff value of HBP was 72.34 ng/mL, its specificity reached 96.1% and its sensitivity was 57.8%. When PCT and CRP levels were less than 1.67 ng/mL and 23.12 ng/mL, respectively, both the sensitivity (52.3%, 53.1%) and specificity (66.9%, 59.9%) were relatively low.

Conclusion

HBP, PCT, and CRP can be employed as diagnostic indicators for bacterial intracranial infection. HBP (>72.34 ng/mL) can act as an important index for the diagnosis of Gram-negative bacteria in patients with intracranial infection.

Epidemiological Manifestations of Purulent Bacterial Meningitis in the Russian Federation

Relevance. Although meningitis is largely preventable, it still causes hundreds of thousands of deaths worldwide each year. Significant progress has been made in reducing meningitis mortality over the past three decades. The incidence of meningococcal, pneumococcal, and Haemophilus influenzae type b meningitis has declined due to the introduction of vaccination into national immunization programs in countries around the world. Aim. To determine the epidemiological manifestations of purulent bacterial meningitis (GBM) in the Russian Federation (RF) in 2023. Materials and methods. An in-depth personalized system for recording purulent bacterial meningitis cases has been established at the Russian Reference Center for Bacterial Meningitis Monitoring. Since 2010, all territories of the Russian Federation have been included in the monitoring system. In 2023, the Reference Center received information on 1,837 cases of purulent bacterial meningitis. The paper uses a descriptive and evaluative epidemiological method: retrospective analysis. Results and discussion. The incidence of GBM in the Russian Federation over a fourteen-year observation period has a downward trend. Meningococcus, pneumococcus and Haemophilus influenzae are the causes of 85% of GBM cases in the Russian Federation, while the infections they cause are potentially vaccine-preventable. Meningococcus continues to occupy a leading position in the etiology of GBM in the Russian Federation, causing 50% of all laboratory-confirmed cases. Despite a slight decrease in the incidence of meningococcal infection in 2023, its increase in the age group at risk, children under 5 years of age, by 39% was noted. In the serogroup characteristics of meningococcus, for the first time in the studied period, the predominance of meningococcus serogroup W was revealed. In 2023, the highest mortality rate from meningococcal infection was noted – 21%. The incidence rate of pneumococcal meningitis in the age group at risk, children under 5 years old, increased to 28% in 2023, and categories of adults are defined as risk groups for mortality. The incidence of meningitis caused by Haemophilus influenzae among children under 5 years old decreased by 44%, and all cases of death, with the exception of one, were noted in this age group. Conclusion. The data obtained make it possible to track the etiology of GBM, age groups and risk areas, which can serve as a basis for developing tactics to combat the disease with priority use of vaccines.

Inflammation of the nasal mucosa is associated with susceptibility to experimental pneumococcal challenge in older adults

Streptococcus pneumoniae colonization in the upper respiratory tract is linked to pneumococcal disease development, predominantly affecting young children and older adults. As the global population ages and comorbidities increase, there is a heightened concern about this infection. We investigated the immunological responses of older adults to pneumococcal-controlled human infection by analyzing the cellular composition and gene expression in the nasal mucosa. Our comparative analysis with data from a concurrent study in younger adults revealed distinct gene expression patterns in older individuals susceptible to colonization, highlighted by neutrophil activation and elevated levels of CXCL9 and CXCL10. Unlike younger adults challenged with pneumococcus, older adults did not show recruitment of monocytes into the nasal mucosa following nasal colonization. However, older adults who were protected from colonization showed increased degranulation of cluster of differentiation 8+ T cells, both before and after pneumococcal challenge. These findings suggest age-associated cellular changes, in particular enhanced mucosal inflammation, that may predispose older adults to pneumococcal colonization.

Detection of intrathecal IgG antibody for varicella and measles diagnosis by evaluation and comparison of a commercial IgG chemiluminescent immunoassay with two ELISAs

OBJECTIVES

Analyse alternative methods of intrathecal antibody detection by comparing chemiluminescent immunoassay (CLIA) and enzyme-linked immunosorbent assay (ELISA) techniques to determine if CLIA can replace ELISA in the diagnosis of CNS infections.

METHODS

A panel of 280 paired samples-cerebrospinal fluid (CSF) and serum-with known antibody reactivities (Varicella, n = 60; Measles, n = 120) and negative samples (n = 100) were used to evaluate the performance of six serological test kits (Enzygnost, VirClia®, and Serion ELISA (Measles and Variella).

RESULTS

For Measles virus IgG, the VirClia® IgG monotest revealed 97% and 94% positive and negative agreement to the Enzygnost as reference test, respectively. In contrast, Serion ELISA kits yielded values of 18% and 90%. For the Varicella Zoster virus (VZV) IgG, the VirClia® IgG monotest showed 97% and 90% positive and negative agreement compared to Enzygnost. The Serion ELISA kits showed values of 55% and 86%, respectively. ROC analysis revealed that the areas under the curve for Measles and VZV IgGs were 0.7 and 0.852, respectively, using the Serion kit, and 0.963 and 0.955, for Vircell S.L CLIA technique. VirClia® monotest values were calculated using an antibody index cut-off of 1.3.

CONCLUSION

The findings indicate that CLIA testing can improve antibody detection in CSF samples, aiding the diagnosis of infectious neurological impairments.

Clinical research progress on intrathecal glucocorticoids in the treatment of infections: A review

In some infectious diseases, pathogenic microorganisms can directly or indirectly cause significant inflammatory reactions in the central nervous system, leading to severe neurological dysfunction, such as suppurative meningitis, tuberculous meningitis, and febrile infections. related epilepsy syndrome, etc. In these diseases, adjuvant administration of glucocorticoids is necessary to inhibit the release of proinflammatory cytokines, and intrathecal administration can deliver the drug more directly to the target. In this article, the authors studied intrathecal glucocorticoids for the treatment of infectious inflammatory reactions in terms of pharmacological effects and mechanisms, pharmacokinetics, clinical application, and safety. The authors concluded that the article could help provide new treatment strategies for infectious diseases.

Clinical characteristics and outcomes of acute bacterial meningitis in adults at a tertiary university hospital in Thailand

The epidemiology of acute bacterial meningitis varies among settings, areas, and times. This study aimed to determine the clinical characteristics, the causative organisms and their antibiotic susceptibility, and the outcomes of patients with acute bacterial meningitis in Thai adults. This retrospective study included hospitalized patients aged ≥18 years diagnosed with acute bacterial meningitis at Siriraj Hospital during January 2002-December 2016. Of 390 patients, the median age was 48 years, 51% were male, and 80% had at least 1 underlying illness. Over half (54%) of patients had community-acquired bacterial meningitis (CBM), and 46% had nosocomial bacterial meningitis (NBM). The triad of acute bacterial meningitis (fever, headache, and neck stiffness) was found in 46% of CBM and 15% of NBM (P < .001). The causative organisms were identified in about half (53%) of patients. Most study patients (73%) received antibiotic treatment before the CSF collection. Causative organisms were identified more frequently in CBM (P < .001). Gram-positive cocci were more prevalent in CBM (P < .001), whereas Gram-negative bacilli were more common in NBM (P < .001). Streptococcus agalactiae (29%), Streptococcus pneumoniae (12%), and Streptococcus suis (11%) were most common in CBM, and all of them were sensitive to third-generation cephalosporins. Acinetobacter baumannii (19%), Klebsiella pneumoniae (16%), and Staphylococcus aureus (11%) were the most common organisms in NBM, and antibiotic-resistant isolates were frequently found among these organisms. Ceftriaxone monotherapy and meropenem plus vancomycin were the most common empiric antibiotic in CBM and NBM, respectively. Mortality was 19% among CBM and 23% among NBM (P = .338). HIV infection, alcoholism, pneumonia, shock, and disseminated intravascular coagulation were independent predictors of mortality. Mortality remains high among adults with acute bacterial meningitis in Thailand. A clinical practice guideline for acute bacterial meningitis should be developed that is based on local epidemiology and microbiology data.

RNA sequencing reveals differential long noncoding RNA expression profiles in bacterial and viral meningitis in children

BACKGROUND

We aimed to investigate the involvement of long non-coding RNA (lncRNA) in bacterial and viral meningitis in children.

METHODS

The peripheral blood of five bacterial meningitis patients, five viral meningitis samples, and five healthy individuals were collected for RNA sequencing. Then, the differentially expressed lncRNA and mRNA were detected in bacterial meningitis vs. controls, viral meningitis vs. healthy samples, and bacterial vs. viral meningitis patients. Besides, co-expression and the competing endogenous RNA (ceRNA) networks were constructed. Receiver operating characteristic curve (ROC) analysis was performed.

RESULTS

Compared with the control group, 2 lncRNAs and 32 mRNAs were identified in bacterial meningitis patients, and 115 lncRNAs and 54 mRNAs were detected in viral meningitis. Compared with bacterial meningitis, 165 lncRNAs and 765 mRNAs were identified in viral meningitis. 2 lncRNAs and 31 mRNAs were specific to bacterial meningitis, and 115 lncRNAs and 53 mRNAs were specific to viral meningitis. The function enrichment results indicated that these mRNAs were involved in innate immune response, inflammatory response, and immune system process. A total of 8 and 1401 co-expression relationships were respectively found in bacterial and viral meningitis groups. The ceRNA networks contained 1 lncRNA-mRNA pair and 4 miRNA-mRNA pairs in viral meningitis group. GPR68 and KIF5C, identified in bacterial meningitis co-expression analysis, had an area under the curve (AUC) of 1.00, while the AUC of OR52K2 and CCR5 is 0.883 and 0.698, respectively.

CONCLUSIONS

Our research is the first to profile the lncRNAs in bacterial and viral meningitis in children and may provide new insight into understanding meningitis regulatory mechanisms.

Diagnostic status and epidemiological characteristics of community-acquired bacterial meningitis in children from 2019 to 2020: a multicenter retrospective study

Community-acquired bacterial meningitis (CABM) is the main cause of morbidity and mortality in children. The epidemiology of CABM is regional and highly dynamic. To clarify the diagnostic status and epidemiological characteristics of children with CABM in this region, and pay attention to the disease burden, so as to provide evidence for the prevention and treatment of CABM. By retrospective case analysis, the clinical data of 918 CABM cases in children aged 0-14 years in Zhejiang Province from January, 2019 to December, 2020 were collected. The etiological diagnosis rate of CABM in children was 23.1%, the annual incidence rate 4.42-6.15/100,000, the annual mortality rate 0.06-0.09/100,000,the cure and improvement rate 94.4%, and the case fatality rate 1.4%. The total incidence of neuroimaging abnormalities was 20.6%. The median length of stay for CABM children was 20(16) days, with an average cost of 21,531(24,835) yuan. In addition, the incidence rate was decreased with age. Escherichia coli(E.coli) and group B Streptococcus agalactiae(GBS) were the principal pathogens in CABM infant<3 months(43.3%, 34.1%), and Streptococcus pneumoniae(S. pneumoniae) was the most common pathogen in children ≥ 3 months(33.9%). In conclusion, the annual incidence and mortality of CABM in children aged 0-14 years in Zhejiang Province are at intermediate and low level. The distribution of CABM incidence and pathogen spectrum are different in age; the incidence of abnormal neuroimaging is high; and the economic burden is heavy.

Diagnostic Accuracy of Cerebrospinal Fluid Multiplex Polymerase Chain Reaction Panel Testing in Patients With Suspected Central Nervous System Infections: A Multi-Center Study in the United Arab Emirates

Background Delays in diagnosis and treatment of central nervous system (CNS) infections can lead to significant morbidity and mortality among children and adults. Prior antibiotic treatment is a major hurdle to accurate diagnosis due to falsely negative cerebrospinal fluid (CSF) cultures in partially treated patients. Increasingly, molecular diagnostic methods using multiplex polymerase chain reaction (mPCR) testing on CSF samples are being utilized in clinical practice for timely and accurate diagnosis. However, there is no data regarding the diagnostic accuracy or clinical impact of CSF mPCR testing in the Middle East region. We sought to compare the diagnostic accuracy of an automated mPCR CSF panel with routine CSF culture, the current gold standard, in the United Arab Emirates (UAE).  Methods This single-gated, multi-center, diagnostic accuracy study included patients from birth onwards who were admitted to any of the three participating hospitals with an initial diagnosis of meningitis or encephalitis, between January 2017 and March 2021, and had CSF samples collected for mPCR and culture. Sociodemographic, clinical, and molecular data were collected for all. Results A total of 353 CSF samples were collected from patients from 0-90 years old hospitalized for suspected CNS infection. Children constituted 51% of the study population, and males were slightly over-represented (55.2%). Pathogens were detected by mPCR in 78 (22%) CSF samples, of which 19 (24%) were bacteria and 59 (76%) were viruses. No fungal pathogens were detected. Enteroviruses were the most prevalent CNS pathogen among our cohort (40%), followed by herpes simplex virus type 2 (HSV-2) (12.5%). Children constituted 69% of positive samples for enterovirus, while HSV-2 was exclusively detected among adults. Using CSF culture as the diagnostic gold standard, the mPCR panel demonstrated high specificity (100%) and sensitivity (96.3%) in diagnosing CNS infection among all age groups. mPCR testing demonstrated a high overall percentage of agreement (OPA) with CSF culture (98.9%). Patients with bacterial meningitis had a significantly longer hospitalization (p=0.004) and duration of antibiotic therapy (p=0.001) compared to those with viral meningitis. Three CSF samples were negative on mPCR testing but positive on culture. These pathogens included: methicillin-sensitive Staphylococcus aureus(MSSA), Bacillus cereus, and Mycobacterium Tuberculosis (MTB). In addition, 13 patients had negative CSF cultures but tested positive on CSF mPCR. These pathogens included Streptococcus pneumoniae (seven patients), Haemophilus influenzae (three patients), Streptococcus agalactiae (two patients), and Escherichia coli (one patient). All discordant results were confirmed by reviewing the patient's clinical presentation, CSF analysis, clinical course, and final diagnosis. Conclusion CSF mPCR panel is a highly sensitive and specific diagnostic tool for the diagnosis of CNS infections among all age groups in the UAE. Routine use of CSF mPCR panels can decrease healthcare costs by reducing the length of stay and can also aid antibiotic stewardship efforts by reducing antibiotic overuse in patients with viral CSF infections. CSF culture and mPCR complement each other by identifying CNS pathogens in patients with prior antibiotic exposure who would otherwise be missed if relying on CSF culture alone. However, concomitant CSF culture samples should be sent to avoid missing unusual CNS pathogens.

Demographic profiles and risk factors for mortality in acute meningitis: A nationwide population-based observational study

Aim

Acute meningitis encompasses bacterial, viral (aseptic), fungal, tuberculous, and carcinomatous meningitis. The rate and risks of mortality in each type remain uncertain. This study aimed to elucidate these aspects in each type of meningitis.

Methods

This study utilized Japan's nationwide administrative Diagnosis Procedure Combination (DPC) database. Patients with acute meningitis, treated at 1132 DPC-covered hospitals from 2016 to 2022, were enrolled.

Results

Among 47,366,222 cumulative hospitalized patients, 48,758 (0.10%) were hospitalized with acute meningitis. The types of meningitis were as follows: 10,338 with bacterial, 29,486 with viral/aseptic, 965 with fungal, 678 with tuberculous, and 3790 with carcinomatous meningitis. Bacterial and viral meningitis exhibited bimodal age distributions, with the first peak occurring at 0-9 years. The median onset age was below 50 years only in viral meningitis. The mortality rate was the highest in carcinomatous meningitis (39%), followed by fungal meningitis (21%), and the lowest in viral meningitis (0.61%). Mortality rates increased with age across all meningitis types, but this trend was less prominent in carcinomatous meningitis. The duration from admission to mortality was longer in fungal and tuberculous meningitis compared with other types. Staphylococcus aureus in bacterial meningitis (adjusted odds ratio 1.71; p = 0.0016) and herpes simplex virus in viral meningitis (adjusted odds ratio 1.53; p = 0.0467) exhibited elevated mortality rates.

Conclusion

Distinct demographic profiles and mortality rates were observed among different meningitis types. The high mortality rates in less common types of meningitis emphasize the necessity to further optimize the required diagnostic and treatment strategies.

Acute meningitis followed by Campylobacter jejuni associated Guillain-Barré Syndrome in a pediatric patient with COVID-19: a case report

Aim of the study: The association of GBS and meningitis in a pediatric population is infrequent. Given the limited number of reported cases from pediatric patients and considering that treatment guidelines are predominantly based on data gathered from adult patients; this is an opportunity to pay attention to different perspectives.Materials and methods: We present a case of a pediatric patient with a positive SARS-CoV2 test and acute meningitis followed by Campylobacter jejuni associated Guillain-Barré Syndrome.Results: To our knowledge, this is the first case of a pediatric patient presenting with the combination Guillain-Barré Syndrome following acute meningitis in the setting of a SARS-CoV2 infection.Conclusions: This case highlights the importance of recognizing vague and non-specific symptoms in pediatric patients, such as gait unsteadiness. Improving awareness of uncommon associations improves treatment and patient outcomes.

Magnetically-targetable outer-membrane vesicles for sonodynamic eradication of antibiotic-tolerant bacteria in bacterial meningitis

Treatment of acute bacterial meningitis is difficult due to the impermeability of the blood-brain barrier, greatly limiting the antibiotic concentrations that can be achieved in the brain. Escherichia coli grown in presence of iron-oxide magnetic nanoparticles secrete large amounts of magnetic outer-membrane vesicles (OMVs) in order to remove excess Fe from their cytoplasm. OMVs are fully biomimetic nanocarriers, but can be inflammatory. Here, non-inflammatory magnetic OMVs were prepared from an E. coli strain in which the synthesis of inflammatory lipid A acyltransferase was inhibited using CRISPR/Cas9 mediated gene knockout. OMVs were loaded with ceftriaxone (CRO) and meso-tetra-(4-carboxyphenyl)porphine (TCPP) and magnetically driven across the blood-brain barrier for sonodynamic treatment of bacterial meningitis. ROS-generation upon ultrasound application of CRO- and TCPP-loaded OMVs yielded similar ROS-generation as by TCPP in solution. In vitro, ROS-generation by CRO- and TCPP-loaded OMVs upon ultrasound application operated synergistically with CRO to kill a hard-to-kill, CRO-tolerant E. coli strain. In a mouse model of CRO-tolerant E. coli meningitis, CRO- and TCPP-loaded OMVs improved survival rates and clinical behavioral scores of infected mice after magnetic targeting and ultrasound application. Recurrence did not occur for at least two weeks after arresting treatment.

A Multicenter Epidemiological and Pathogenic Characteristics Study of Community-Acquired Bacterial Meningitis Children in China: Results from the Chinese Pediatric Bacterial Meningitis Surveillance (CPBMS) 2019-2020

Objective

To explore the epidemiological and pathogenic characteristics of children with community-acquired bacterial meningitis.

Methods

A multicenter, retrospective study was conducted among CABM patients under 15 years old from 33 hospitals in China from 2019 to 2020. The medical record, laboratory, and microbiological data were collected and analyzed.

Results

A total of 1610 children with CABM were identified and presented at a median onset age of 45 days of whom 955 (59.3%) were males. CABM occurred mostly in infants <1 year of age (84.0%, 1352/1610). In etiology-confirmed cases, the pathogens were isolated from CSF culture in 515 (32.0%), 400 (24.8%) in blood culture, and 186 (11.6%) both in CSF and blood culture. In total, 126 pathogens were identified through CSF mNGS in 330 CABM cases; 21 S. pneumoniae isolates were detected in 83 CABM cases by antigen detection method. Major pathogens were E. coli (195, 24.7%), GBS (170, 21.5%), and S. pneumoniae (157, 19.9%). GBS (29.3%, 22/75) was the first pathogen of CABM in neonates aged 0-6 days old, while E. coli (44.7%, 76/170) in 7 to 28 days of age; S. pneumoniae (96.2%, 151/157) was the most common pathogen in >3 months old cases. About 9.7% (19/195) strains of E. coli produced ultra‑broad‑spectrum β‑lactamases. The common intracranial imaging complications were subdural effusion and (or) empyema in 349 (21.7%), hydrocephalus in 233 (14.5%), and cerebral abscess in 178 (11.1%). A total of 389 (24.2%) cases were completely cured and 1088 (67.6%) cases improved. Among 166 patients (10.3%) with adverse outcomes, 32 cases (2.0%) died, and 37 cases (2.3%) relapsed.

Conclusion

The onset age of CABM in children is usually within 1 year of age, especially <3 months. The primary pathogens in infants less than 3 months old are E. coli and GBS, and the dominant pathogen in children older than 3 months old is S. pneumoniae. Subdural effusion and (or) empyema and hydrocephalus are common complications. CABM should not be excluded even if CSF leukocyte counts are within normal range. Due to the low detection rate of pathogens in children with CABM, standardized CSF bacteriological examination should be paid more attention to increase the pathogen detection rate. Non‑culture CSF detection methods may facilitate pathogenic diagnosis.

Meningeal regulation of infections: A double-edged sword

In the past 10 years, important discoveries have been made in the field of neuroimmunology, especially regarding brain borders. Indeed, meninges are protective envelopes surrounding the CNS and are currently in the spotlight, with multiple studies showing their involvement in brain infection and cognitive disorders. In this review, we describe the meningeal layers and their protective role in the CNS against bacterial, viral, fungal, and parasitic infections, by immune and nonimmune cells. Moreover, we discuss the neurological and cognitive consequences resulting from meningeal infections in neonates (e.g. infection with group B Streptococcus, cytomegalovirus, …) or adults (e.g. infection with Trypanosoma brucei, Streptococcus pneumoniae, …). We hope that this review will bring to light an integrated view of meningeal immune regulations during CNS infections and their neurological consequences.

Global, regional, and national burden of meningitis and its aetiologies, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019

BACKGROUND

Although meningitis is largely preventable, it still causes hundreds of thousands of deaths globally each year. WHO set ambitious goals to reduce meningitis cases by 2030, and assessing trends in the global meningitis burden can help track progress and identify gaps in achieving these goals. Using data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, we aimed to assess incident cases and deaths due to acute infectious meningitis by aetiology and age from 1990 to 2019, for 204 countries and territories.

METHODS

We modelled meningitis mortality using vital registration, verbal autopsy, sample-based vital registration, and mortality surveillance data. Meningitis morbidity was modelled with a Bayesian compartmental model, using data from the published literature identified by a systematic review, as well as surveillance data, inpatient hospital admissions, health insurance claims, and cause-specific meningitis mortality estimates. For aetiology estimation, data from multiple causes of death, vital registration, hospital discharge, microbial laboratory, and literature studies were analysed by use of a network analysis model to estimate the proportion of meningitis deaths and cases attributable to the following aetiologies: Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae, group B Streptococcus, Escherichia coli, Klebsiella pneumoniae, Listeria monocytogenes, Staphylococcus aureus, viruses, and a residual other pathogen category.

FINDINGS

In 2019, there were an estimated 236 000 deaths (95% uncertainty interval [UI] 204 000-277 000) and 2·51 million (2·11-2·99) incident cases due to meningitis globally. The burden was greatest in children younger than 5 years, with 112 000 deaths (87 400-145 000) and 1·28 million incident cases (0·947-1·71) in 2019. Age-standardised mortality rates decreased from 7·5 (6·6-8·4) per 100 000 population in 1990 to 3·3 (2·8-3·9) per 100 000 population in 2019. The highest proportion of total all-age meningitis deaths in 2019 was attributable to S pneumoniae (18·1% [17·1-19·2]), followed by N meningitidis (13·6% [12·7-14·4]) and K pneumoniae (12·2% [10·2-14·3]). Between 1990 and 2019, H influenzae showed the largest reduction in the number of deaths among children younger than 5 years (76·5% [69·5-81·8]), followed by N meningitidis (72·3% [64·4-78·5]) and viruses (58·2% [47·1-67·3]).

INTERPRETATION

Substantial progress has been made in reducing meningitis mortality over the past three decades. However, more meningitis-related deaths might be prevented by quickly scaling up immunisation and expanding access to health services. Further reduction in the global meningitis burden should be possible through low-cost multivalent vaccines, increased access to accurate and rapid diagnostic assays, enhanced surveillance, and early treatment.

FUNDING

Bill & Melinda Gates Foundation.

Role of lumbar puncture in clinical outcome of suspected acute bacterial meningitis

BACKGROUND

Meningitis remains a significant source of mortality and morbidity, with an incidence of 1 per 100000 persons in the United States. Guidelines recommend obtaining blood cultures and cerebrospinal fluid (CSF) studies in patients presenting with acute meningitis syndrome, and beginning treatment with broad spectrum antibiotics based on the age and certain predisposing conditions. In some patients however, the diagnostic lumbar puncture (LP) is not performed due to a multitude of reasons, ranging from increased intracranial pressure to failed attempt. In such situations, appropriate therapy is initiated empirically and often continued without establishment of a definitive diagnosis.

AIM

To determine whether a diagnostic LP in acute meningitis syndrome was associated with a better outcome and less duration of antibiotic therapy, along with potential causes for deferral of procedure.

METHODS

A retrospective study was conducted amongst the patients presenting to a 360 bedded community hospital in central Massachusetts with a diagnosis of acute meningitis syndrome between January 2010 – September 2022. The electronic health records were accessed to collect necessary demographic and clinical data, including etiology of meningitis, lumbar puncture results, reason for procedure deferral, duration of antibiotic therapy and clinical outcome. The patients were subsequently divided into two groups based on whether they received a LP or not, and data was analyzed.

RESULTS

A total of 169 patients admitted with acute meningitis syndrome between September 2010-2022 were included in the study. The mean age of the participants was 54.3 years (SD +/- 19.2 years). LP was performed for 130 (76.9%) participants, out of which, 28 (21.5%) showed some growth in CSF culture. The most commonly identified organism was streptococcus pneumoniae. Amongst the 39 patients in whom LP was deferred, the major reasons recorded were: Body habitus (n = 6, 15.4%), and unsuccessful attempt (n = 4, 10.3%). While 93 (71.5%) patients with LP received antibiotic therapy, only 19 (48.7%) patients without LP received the antibiotics, with the principal reason being spontaneous improvement in sensorium without any diagnosed source of infection. The mean duration of antibiotic use was 12.3 days (SD +/- 5.6) in the LP group and 11.5 days (SD +/- 7.0) in the non-LP group (P = 0.56; statistically not significant). We observed higher long term sequalae in the non-LP group (n = 6, 15.4%) compared to the LP group (n = 9, 6.9%). Similarly, the death rate was higher in the non-LP group (n = 7, 18.0%) compared to the LP group (n = 9, 6.9%).

CONCLUSION

LP remains the cornerstone for diagnosing meningitis, but often CSF results are unavailable, leading to empiric treatment. Our study identified that body habitus and unsuccessful attempts were the most common reasons for LP not being performed, leading to empiric antibiotic coverage. There was no difference between the duration of antibiotics received by the two groups, but a lower proportion of patients without LP received antibiotics, attributed to a spontaneous improvement in sensorium. However, the residual neurological sequelae and death rates were higher in patients without LP, signifying a potential under-treatment. A LP remains crucial to diagnose meningitis, and a lack of CSF analysis predisposes to under-treatment, leading to higher neurological sequelae and increased chances of death.

Ebola virus disease: A review for the emergency medicine clinician

INTRODUCTION

Ebolavirus, the causative agent of Ebola virus disease (EVD) has been responsible for sporadic outbreaks mainly in sub-Saharan Africa since 1976. EVD is associated with high risk of transmission, especially to healthcare workers during patient care.

OBJECTIVE

The purpose of this review is to provide a concise review of EVD presentation, diagnosis, and management for emergency clinicians.

DISCUSSION

EVD is spread through direct contact, including blood, bodily fluids or contact with a contaminated object. Patients may present with non-specific symptoms such as fevers, myalgias, vomiting, or diarrhea that overlap with other viral illnesses, but rash, bruising, and bleeding may also occur. Laboratory analysis may reveal transaminitis, coagulopathy, and disseminated intravascular coagulation. The average clinical course is approximately 8-10 days with an average case fatality rate of 50%. The mainstay of treatment is supportive care, with two U.S. Food and Drug Administration-approved monoclonal antibody treatments (Ebanga and Inmazeb). Survivors of the disease may have a complicated recovery, marked by long-term symptoms.

CONCLUSION

EVD is a potentially deadly condition that can present with a wide range of signs and symptoms. Emergency clinicians must be aware of the presentation, evaluation, and management to optimize the care of these patients.

2023 Update on Sepsis and Septic Shock in Adult Patients: Management in the Emergency Department

BACKGROUND

Sepsis/septic shock is a life-threatening and time-dependent condition that requires timely management to reduce mortality. This review aims to update physicians with regard to the main pillars of treatment for this insidious condition.

METHODS

PubMed, Scopus, and EMBASE were searched from inception with special attention paid to November 2021-January 2023.

RESULTS

The management of sepsis/septic shock is challenging and involves different pathophysiological aspects, encompassing empirical antimicrobial treatment (which is promptly administered after microbial tests), fluid (crystalloids) replacement (to be established according to fluid tolerance and fluid responsiveness), and vasoactive agents (e.g., norepinephrine (NE)), which are employed to maintain mean arterial pressure above 65 mmHg and reduce the risk of fluid overload. In cases of refractory shock, vasopressin (rather than epinephrine) should be combined with NE to reach an acceptable level of pressure control. If mechanical ventilation is indicated, the tidal volume should be reduced from 10 to 6 mL/kg. Heparin is administered to prevent venous thromboembolism, and glycemic control is recommended. The efficacy of other treatments (e.g., proton-pump inhibitors, sodium bicarbonate, etc.) is largely debated, and such treatments might be used on a case-to-case basis.

CONCLUSIONS

The management of sepsis/septic shock has significantly progressed in the last few years. Improving knowledge of the main therapeutic cornerstones of this challenging condition is crucial to achieve better patient outcomes.

Integrative diagnostics: the time is now-a report from the International Society for Strategic Studies in Radiology

Enormous recent progress in diagnostic testing can enable more accurate diagnosis and improved clinical outcomes. Yet these tests are increasingly challenging and frustrating; the volume and diversity of results may overwhelm the diagnostic acumen of even the most dedicated and experienced clinician. Because they are gathered and processed within the "silo" of each diagnostic discipline, diagnostic data are fragmented, and the electronic health record does little to synthesize new and existing data into usable information. Therefore, despite great promise, diagnoses may still be incorrect, delayed, or never made. Integrative diagnostics represents a vision for the future, wherein diagnostic data, together with clinical data from the electronic health record, are aggregated and contextualized by informatics tools to direct clinical action. Integrative diagnostics has the potential to identify correct therapies more quickly, modify treatment when appropriate, and terminate treatment when not effective, ultimately decreasing morbidity, improving outcomes, and avoiding unnecessary costs. Radiology, laboratory medicine, and pathology already play major roles in medical diagnostics. Our specialties can increase the value of our examinations by taking a holistic approach to their selection, interpretation, and application to the patient's care pathway. We have the means and rationale to incorporate integrative diagnostics into our specialties and guide its implementation in clinical practice.

Concurrent Sphingomonas paucimobilis and Mycobacterium tuberculosis Meningitis in an Immunocompromised Patient: A Rare Case Report and Comprehensive Review of Literature

Sphingomonas paucimobilis is a gram-negative bacillus that is widely distributed in the environment but rarely causes infections in humans. Meningitis caused by S. paucimobilis is an extremely rare clinical entity with very few reported cases in the literature. The clinical presentation and management of S. paucimobilis meningitis are not well established, and further research is needed to better understand this rare infection. Therefore, the goal of this study was to present probably the only case of meningitis caused by co-infection with S. paucimobilis and Mycobacterium tuberculosis and to describe the diagnostic and therapeutic challenges encountered, in correlation with the other very few reported cases of S. paucimobilis meningitis. A 64-year-old male farmer residing in a rural area was admitted with symptoms of severe headache, somnolence, and confusion. He had several comorbidities, including adrenal insufficiency, duodenal ulcer, and hypercholesterolemia. Lumbar puncture showed elevated leukocyte counts, glucose, and a marked rise of cerebrospinal fluid (CSF) proteins, indicating bacterial meningitis, which was confirmed by CSF culture that isolated S. paucimobilis and Mycobacterium tuberculosis. Antituberculosis therapy was initiated with isoniazid (300 mg/day), rifampicin (600 mg/day), pyrazinamide (2000 mg/day), and streptomycin (1 g/day). Ceftriaxone was introduced nine days later, after CSF culture grew S. paucimobilis, and was discharged without complications after 40 days of hospitalization. The literature search revealed a total of 12 published cases of S. paucimobilis meningitis in patients ranging from two months old to 66 years old. Among these cases, eight (66%) reported a favorable outcome, while two (17%) cases resulted in a poor outcome, and two (17%) were fatal. It was observed among the 13 identified cases (including ours) that the CSF white blood cell count had an average of 178.9 × 10³/mm³, an average glucose level of 33.0 mg/dL, and an average protein count of 294.2 mg/dL. Most cases improved appropriately under antibiotic therapy with intravenous ceftriaxone, Meropenem, and Vancomycin. In conclusion, although extremely rare, S. paucimobilis meningitis has good outcomes even in immunocompromised patients with appropriate antibiotic therapy and close monitoring, while the diagnosis should not be excluded even in immunocompetent patients.

Daptomycin for the treatment of acute bacterial meningitis: a narrative review

BACKGROUND

There is a growing interest in the utilization of daptomycin for the treatment of multi-drug resistant, Gram-positive infections. Pharmacokinetic studies suggest that daptomycin could penetrate into the cerebrospinal fluid, albeit to a small extent. The objective of this review was to evaluate the available clinical evidence for daptomycin use in acute bacterial meningitis of both pediatric and adult patients.

METHODS

Electronic databases were searched up to June 2022 for studies published on the topic. The inclusion criteria were met if the study reported the use of intravenous daptomycin (more than a single dose) for the treatment of diagnosed acute bacterial meningitis.

RESULTS

A total of 21 case reports were identified that met the inclusion criteria. These suggest that daptomycin could be safe and effective alternative in achieving clinical cure of meningitis. In these studies, daptomycin was used in the event of treatment failure, patient intolerance, or bacterial resistance to first-line agents.

CONCLUSIONS

Daptomycin has potential to be an alternative to standard care for meningitis caused by Gram-positive bacteria in the future; however, more robust research is required to establish an optimal dosing regimen, duration of therapy, and place in therapy for the management of meningitis.

Integrative Diagnostics: The Time Is Now-A Report From the International Society for Strategic Studies in Radiology

Enormous recent progress in diagnostic testing can enable more accurate diagnosis and improved clinical outcomes. Yet these tests are increasingly challenging and frustrating; the volume and diversity of results may overwhelm the diagnostic acumen of even the most dedicated and experienced clinician. Because they are gathered and processed within the "silo" of each diagnostic discipline, diagnostic data are fragmented, and the electronic health record does little to synthesize new and existing data into usable information. Therefore, despite great promise, diagnoses may still be incorrect, delayed, or never made. Integrative diagnostics represents a vision for the future, wherein diagnostic data, together with clinical data from the electronic health record, are aggregated and contextualized by informatics tools to direct clinical action. Integrative diagnostics has the potential to identify correct therapies more quickly, modify treatment when appropriate, and terminate treatment when not effective, ultimately decreasing morbidity, improving outcomes, and avoiding unnecessary costs. Radiology, laboratory medicine, and pathology already play major roles in medical diagnostics. Our specialties can increase the value of our examinations by taking a holistic approach to their selection, interpretation, and application to the patient's care pathway. We have the means and rationale to incorporate integrative diagnostics into our specialties and guide its implementation in clinical practice.

Plant based food bioactives: A boon or bane for neurological disorders

Neurological disorders are the foremost occurring diseases across the globe resulting in progressive dysfunction, loss of neuronal structure ultimately cell death. Therefore, attention has been drawn toward the natural resources for the search of neuroprotective agents. Plant-based food bioactives have emerged as potential neuroprotective agents for the treatment of neurodegenerative disorders. This comprehensive review primarily focuses on various plant food bioactive, mechanisms, therapeutic targets, in vitro and in vivo studies in the treatment of neurological disorders to explore whether they are boon or bane for neurological disorders. In addition, the clinical perspective of plant food bioactives in neurological disorders are also highlighted. Scientific evidences point toward the enormous therapeutic efficacy of plant food bioactives in the prevention or treatment of neurological disorders. Nevertheless, identification of food bioactive components accountable for the neuroprotective effects, mechanism, clinical trials, and consolidation of information flow are warranted. Plant food bioactives primarily act by mediating through various pathways including oxidative stress, neuroinflammation, apoptosis, excitotoxicity, specific proteins, mitochondrial dysfunction, and reversing neurodegeneration and can be used for the prevention and therapy of neurodegenerative disorders. In conclusion, the plant based food bioactives are boon for neurological disorders.

Hypervirulent carbapenem-resistant Klebsiella pneumoniae causing highly fatal meningitis in southeastern China

Klebsiella pneumoniae (K. pneumoniae) is one of the most common causes of bacterial meningitis worldwide. The purpose of this study was to investigate the clinical and microbiological characteristics of K. pneumoniae meningitis, as well as the association of antimicrobial resistance, virulence, and patient prognosis. The clinical data of patients with K. pneumoniae meningitis from 2014 to 2020 in a tertiary teaching hospital were retrospectively evaluated. Antimicrobial susceptibility profiles were performed by the agar dilution method and broth microdilution method. The isolates were detected for virulence-related genes, resistance genes, capsular serotypes, and molecular subtypes. A total of 36 individuals with K. pneumoniae meningitis were included in the study, accounting for 11.3% (36/318) of all cases of bacterial meningitis. Of the 36 available isolates, K1, K47, and K64 were tied for the most frequent serotype (7/36, 19.4%). MLST analysis classified the isolates into 14 distinct STs, with ST11 being the most common (14/36, 38.9%). Carbapenem resistance was found in 44.4% (16/36) of the isolates, while hypervirulent K. pneumoniae (HvKP) was found in 66.7% (24/36) of the isolates. The isolates of hypervirulent carbapenem-resistant K. pneumoniae (Hv-CRKP) were then confirmed to be 36.1% (13/36). Importantly, individuals with meningitis caused by Hv-CRKP had a statistically significant higher mortality than the other patients (92.3%, 12/13 vs. 56.5%, 13/23; P < 0.05). The high percentage and fatality of K. pneumoniae-caused meningitis, particularly in Hv-CRKP strains, should be of significant concern. More effective surveillance and treatment solutions will be required in future to avoid the spread of these life-threatening infections over the world.

Vimentin as a potential target for diverse nervous system diseases

Vimentin is a major type III intermediate filament protein that plays important roles in several basic cellular functions including cell migration, proliferation, and division. Although vimentin is a cytoplasmic protein, it also exists in the extracellular matrix and at the cell surface. Previous studies have shown that vimentin may exert multiple physiological effects in different nervous system injuries and diseases. For example, the studies of vimentin in spinal cord injury and stroke mainly focus on the formation of reactive astrocytes. Reduced glial scar, increased axonal regeneration, and improved motor function have been noted after spinal cord injury in vimentin and glial fibrillary acidic protein knockout (GFAP^-/-VIM^-/-) mice. However, attenuated glial scar formation in post-stroke in GFAP^-/- VIM^-/- mice resulted in abnormal neuronal network restoration and worse neurological recovery. These opposite results have been attributed to the multiple roles of glial scar in different temporal and spatial conditions. In addition, extracellular vimentin may be a neurotrophic factor that promotes axonal extension by interaction with the insulin-like growth factor 1 receptor. In the pathogenesis of bacterial meningitis, cell surface vimentin is a meningitis facilitator, acting as a receptor of multiple pathogenic bacteria, including E. coli K1, Listeria monocytogenes, and group B streptococcus. Compared with wild type mice, VIM^-/- mice are less susceptible to bacterial infection and exhibit a reduced inflammatory response, suggesting that vimentin is necessary to induce the pathogenesis of meningitis. Recently published literature showed that vimentin serves as a double-edged sword in the nervous system, regulating axonal regrowth, myelination, apoptosis, and neuroinflammation. This review aims to provide an overview of vimentin in spinal cord injury, stroke, bacterial meningitis, gliomas, and peripheral nerve injury and to discuss the potential therapeutic methods involving vimentin manipulation in improving axonal regeneration, alleviating infection, inhibiting brain tumor progression, and enhancing nerve myelination.

The Next Frontier in Neurocritical Care in Resource-Constrained Settings

Neurocritical care (NCC) is an emerging field within critical care medicine, reflecting the widespread prevalence of neurologic injury in critically ill patients. Morbidity and mortality from neurocritical illness (NCI) have been reduced substantially in resource-rich settings (RRS), owing to the development of advanced technologies, neuro-specific units, and subspecialized medical training. Despite shouldering much of the burden of NCI worldwide, resource-limited settings (RLS) face immense hurdles when implementing guidelines generated in RRS. This review summarizes the current epidemiology, management, and outcomes of the most common NCIs in RLS and offers commentary on future directions in NCC practiced in RLS.

Critical care management of meningitis and encephalitis: an update

PURPOSE OF REVIEW

Meningitis and encephalitis represent severe neurological syndromes associated with encephalopathy, seizures, focal deficits, and neurological sequelae in survivors. We update on the critical care management of adult patients with severe meningitis and encephalitis.

RECENT FINDINGS

Large multicenter studies conducted in the adult population improved current knowledge on the epidemiology and outcomes of patients with severe meningitis and encephalitis. An early multimodal diagnostic workup (including CSF analysis, brain MRI, EEG, and serum studies) is mandatory for diagnosis and prognostication in those patients.New diagnostic methods, including multiplex PCR and next-generation sequencing techniques, allow for a faster differential diagnosis of infectious causes that may require specific antimicrobial therapy. Autoimmune causes of encephalitis, which may require urgent immunotherapy, are also increasingly recognized in the ICU setting. Although observational data suggest that early combined immunotherapy is associated with better neurological outcomes in patients with autoimmune encephalitis, randomized clinical trials have yet to be performed.

SUMMARY

Our review highlights the importance of an early multimodal approach for diagnosing severe meningitis and encephalitis. Randomized clinical trials are needed to identify pharmacological interventions that may improve patients' outcomes.

Risk Factors of Postoperative Meningitis in Lateral Ventricular Trigone Meningiomas: A Clinical Analysis of 64 Patients

Purpose

Patients with intraventricular tumors are more susceptible to postoperative meningitis (POM) than other intracranial tumors. In this study, we explored the risk factors of POM in lateral ventricular trigone meningiomas (LVTMs).

Methods

Clinical features of 64 patients with LVTMs were analyzed. Age, gender, body mass index, medical history, intraoperative blood loss (IBL), intraventricular drainage placement, surgical duration, tumor grade, postoperative tumor cavity hemorrhage, and tumor size were included in univariate and multivariate analyses of POM.

Results

Of the 64 patients, 14 patients (21.9%) received diagnosis of POM. The univariate analysis revealed IBL ≥400 mL (odds ratio [OR], 9.012; p = 0.003), tumor size ≥50 cm³ (OR, 3.071; p = 0.080), and surgical duration ≥5 h (OR, 2.970; p = 0.085) were considered possible risk factors for POM (p < 0.10). Tumor size (R = 0.514) and surgical duration (R = 0.624) were significantly correlated with IBL (p < 0.05). In the multivariate analysis, only IBL was found to be an independent risk factor for POM.

Conclusion

The IBL ≥400 mL is independently associated with the increased risk of POM in LVTM patients. Our results demonstrate the importance of controlling IBL for preventing POM, especially in large tumors and long surgeries.

Cerebrospinal fluid analysis: current diagnostic methods in central nervous system infectious diseases

Cerebrospinal fluid (CSF) analysis is an important diagnostic tool for many conditions affecting the central nervous system (CNS), especially CNS infectious diseases. Despite its low specificity, CSF white blood cell counts, CSF protein levels, CSF serum glucose ratio and CSF lactate measurement are useful in differentiating infections caused by distinct groups of pathogens. CSF direct examination and cultures can identify causative organisms and antibiotic sensitivities as well. Adjunctive tests such as latex agglutination, different immunological assays and molecular reactions have great specificities and increasing sensitivities. In this article, some recent diagnostic methods applied to CSF analysis for frequent CNS infections are presented.

Methylome and Transcriptome-Based Integration Analysis Identified Molecular Signatures Associated With Meningitis Induced by Glaesserella parasuis

Glaesserella parasuis (G. parasuis) can elicit serious inflammatory responses and cause meningitis in piglets. Previous epigenetic studies have indicated that alterations in host DNA methylation may modify the inflammatory response to bacterial infection. However, to date, genome-wide analysis of the DNA methylome during meningitis caused by G. parasuis infection is still lacking. In this study, we employed an unbiased approach using deep sequencing to profile the DNA methylome and transcriptome from G. parasuis infected porcine brain (cerebrum) and integrated the data to identify key differential methylation regions/sites involved in the regulation of the inflammatory response. Results showed that DNA methylation patterns and gene expression profiles from porcine brain were changed after G. parasuis infection. The majority of the altered DNA methylation regions were found in the intergenic regions and introns and not associated with CpG islands, with only a low percentage occurring at promoter or exon regions. Integrated analysis of the DNA methylome and transcriptome identified a number of inversely and positively correlated genes between DNA methylation and gene expression, following the criteria of |log₂FC| > 0.5, |diffMethy| > 0.1, and P < 0.05. Differential expression and methylation of two significant genes, semaphoring 4D (SEMA4D) and von Willebrand factor A domain containing 1 (VWA1), were validated by qRT-PCR and bisulfite sequencing. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses demonstrated that DNA methylation inversely correlated genes in G. parasuis infected porcine brains were mainly involved with cell adhesion molecules (CAMs), bacterial invasion of epithelial cells, RIG-1-like receptor signaling pathways, and hematopoietic cell lineage signaling pathways. In addition, a protein-protein interaction network of differentially methylated genes found potential candidate molecular interactions relevant to the pathology of G. parasuis infection. To the best of our knowledge, this is the first attempt to integrate the DNA methylome and transcriptome data from G. parasuis infected porcine brains. Our findings will help understanding the contribution of genome-wide DNA methylation to the pathogenesis of meningitis in pigs and developing epigenetic biomarkers and therapeutic targets for the treatment of G. parasuis induced meningitis.

Community-acquired bacterial meningitis

Progress has been made in the prevention and treatment of community-acquired bacterial meningitis during the past three decades but the burden of the disease remains high globally. Conjugate vaccines against the three most common causative pathogens (Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae) have reduced the incidence of disease, but with the replacement by non-vaccine pneumococcal serotypes and the emergence of bacterial strains with reduced susceptibility to antimicrobial treatment, meningitis continues to pose a major health challenge worldwide. In patients presenting with bacterial meningitis, typical clinical characteristics (such as the classic triad of neck stiffness, fever, and an altered mental status) might be absent and cerebrospinal fluid examination for biochemistry, microscopy, culture, and PCR to identify bacterial DNA are essential for the diagnosis. Multiplex PCR point-of-care panels in cerebrospinal fluid show promise in accelerating the diagnosis, but diagnostic accuracy studies to justify routine implementation are scarce and randomised, controlled studies are absent. Early administration of antimicrobial treatment (within 1 hour of presentation) improves outcomes and needs to be adjusted according to local emergence of drug resistance. Adjunctive dexamethasone treatment has proven efficacy beyond the neonatal age but only in patients from high-income countries. Further progress can be expected from implementing preventive measures, especially the development of new vaccines, implementation of hospital protocols aimed at early treatment, and new treatments targeting checkpoints of the inflammatory cascade.