Community-acquired bacterial meningitis in adults in the Netherlands, 2006-14: a prospective cohort study

Use of Metagenomic Next-Generation Sequencing to Identify Pathogens Involved in Central Nervous System Infections

Purpose

Application of metagenomic next-generation sequencing (mNGS) in identifying nosocomial central nervous system (CNS) infections in critical care units remains understudied.

Methods

We conducted a retrospective analysis of microbiological results through both mNGS and routine examination of cerebrospinal fluid (CSF) samples from patients with nosocomial CNS infections. The aim of this study was to assess the clinical diagnostic effect of nosocomial mNGS in this population.

Results

The study included 26 cases of nosocomial CNS infections in total. A total of 69.2% (18/26) of the samples tested positive for mNGS, which is substantially greater than the 7.7% (2/26; p<0.05) detected through conventional techniques. Administration of antibiotics before culture is most likely the cause of the low CSF culture rate. Twenty-five pathogenic strains that were missed by standard testing. Three pathogens that were consistent with the mNGS results were positive by routine tests. Eight cases were negative by mNGS due to low pathogen CSF titres. Compared to traditional testing, mNGS demonstrated 100% sensitivity and 33.3% specificity in diagnosing CNS infections. The thirty-day mortality rate was 26.9% (7/26).

Conclusion

Routine microbiologic testing frequently falls short of detecting all neuroinvasive pathogens. Our research suggests that mNGS offers an alternative means of detecting nosocomial CNS infections. By applying mNGS to CSF samples from patients with meningitis or encephalitis, we were able to improve the ability to diagnose nosocomial neurologic infections.

Otitis in Patients With Community-Acquired Bacterial Meningitis: A Nationwide Prospective Cohort Study

BACKGROUND

Otitis is commonly associated with community-acquired bacterial meningitis, but the role of ear surgery as treatment is debated. In this study, we investigated the impact of otitis and ear surgery on outcome of adults with community-acquired bacterial meningitis.

METHODS

We analyzed episodes of adults with community-acquired bacterial meningitis from a nationwide prospective cohort study in the Netherlands, between March 2006 and July 2021.

RESULTS

A total of 2548 episodes of community-acquired bacterial meningitis were evaluated. Otitis was present in 696 episodes (27%). In these patients the primary causative pathogen was Streptococcus pneumoniae (615 of 696 [88%]), followed by Streptococcus pyogenes (5%) and Haemophilus influenzae (4%). In 519 of 632 otitis episodes (82%) an ear-nose-throat specialist was consulted, and surgery was performed in 287 of 519 (55%). The types of surgery performed were myringotomy with ventilation tube insertion in 110 of 287 episodes (38%), mastoidectomy in 103 of 287 (36%), and myringotomy alone in 74 of 287 (26%). Unfavorable outcome occurred in 210 of 696 episodes (30%) and in 65 of 696 episodes was fatal (9%). Otitis was associated with a favorable outcome in a multivariable analysis (odds ratio 0.74; 95% confidence interval [CI] .59-.92; P = .008). There was no association between outcome and ear surgery.

CONCLUSIONS

Otitis is a common focus of infection in community-acquired bacterial meningitis in adults, with S. pneumoniae being the most common causative pathogen. Presence of otitis is associated with a favorable outcome. Ear surgery's impact on the outcome of otogenic meningitis patients remains uncertain.

Burden and bacterial etiology of neonatal meningitis at Hawassa University Comprehensive Specialized Hospital, Hawassa, Ethiopia

BACKGROUND

Meningitis poses a significant challenge to public health in low-income nations, such as Ethiopia, with a particular impact on newborns. The magnitude and etiologies of meningitis vary based on geographic location and age of patients. There is limited data regarding the magnitude and etiology of meningitis from Sidama Regional State, Ethiopia. This study aimed to determine the magnitude and bacterial profile of meningitis among newborns aged less than 90 days at Hawassa University Comprehensive Specialized Hospital (HUCSH).

METHODS

A retrospective cross-sectional study was conducted among newborns under 90 days who were suspected of meningitis at HUCSH from January 2019 to July 2023, and for whom Cerebrospinal fluid (CSF) culture was performed. At HUCSH, bacteria are isolated and identified using standard microbiological techniques. Socio-demographic characteristics and culture results were extracted from the laboratory register. Data were entered into Excel and exported it to SPSS version 20 for analysis.

RESULTS

Overall 1061 newborns suspected of meningitis were included in the study. Among the participants, 767 individuals (72.3%) fell within the age range of 8 to 90 days. Of the total participants, 437 (41.2%) were females. The magnitude of culture-confirmed meningitis was 90(8.5%) 95% CI: 6.8%-10.1%. The magnitude of culture-confirmed meningitis among newborns aged 0-7 days and 8-90 days were 1.6% and 6.9% respectively. The proportion of bacteria among newborns aged 0-7 days and 8-90 days were 18.9% and 81.1% respectively. Coagulase-negative Staphylococci (CONS) were the most common bacteria (n = 26; 28.9%) recovered followed by Acinetobacter species (n = 12, 13.3%), Escherichia coli (n = 9; 10%), and Klebsiella pneumoniae (n = 7; 7.8%). K. pneumoniae was the predominant bacteria among newborns within the age group of 0 to 7 days while Acinetobacter species was the most common among newborns within the 8 to 90 days age group. The prevalence of culture-confirmed neonatal meningitis was found to be greater in male newborns (x2 = 1.74, p = 0.18), newborns aged between 8 to 90 days (x2 = 0.07, p = 3.4), and newborns admitted in 2022 (x2 = 2.4, p = 0.66).

CONCLUSIONS

In this study, the overall magnitude of culture-confirmed meningitis was relatively high. Culture-confirmed meningitis was high in newborns within the age range of 8 to 90 days. The most common bacteria were CONS in both age groups followed by Acinetobacter species, E. coli, and K. pneumoniae.

Global Case Fatality of Bacterial Meningitis During an 80-Year Period: A Systematic Review and Meta-Analysis

Importance

The impact of vaccination, antibiotics, and anti-inflammatory treatment on pathogen distribution and outcome of bacterial meningitis over the past century is uncertain.

Objective

To describe worldwide pathogen distribution and case fatality ratios of community-acquired bacterial meningitis.

Data Sources

Google Scholar and MEDLINE were searched in January 2022 using the search terms bacterial meningitis and mortality.

Study Selection

Included studies reported at least 10 patients with bacterial meningitis and survival status. Studies that selected participants by a specific risk factor, had a mean observation period before 1940, or had more than 10% of patients with health care-associated meningitis, tuberculous meningitis, or missing outcome were excluded.

Data Extraction and Synthesis

Data were extracted by 1 author and verified by a second author. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Random-effects models stratified by age (ie, neonates, children, adults), Human Development Index (ie, low-income or high-income countries), and decade and meta-regression using the study period's year as an estimator variable were used.

Main Outcome and Measure

Case fatality ratios of bacterial meningitis.

Results

This review included 371 studies performed in 108 countries from January 1, 1935, to December 31, 2019, describing 157 656 episodes. Of the 33 295 episodes for which the patients' sex was reported, 13 452 (40%) occurred in females. Causative pathogens were reported in 104 598 episodes with Neisseria meningitidis in 26 344 (25%) episodes, Streptococcus pneumoniae in 26 035 (25%) episodes, Haemophilus influenzae in 22 722 (22%), other bacteria in 19 161 (18%) episodes, and unidentified pathogen in 10 336 (10%) episodes. The overall case fatality ratio was 18% (95% CI, 16%-19%), decreasing from 32% (95% CI, 24%-40%) before 1961 to 15% (95% CI, 12%-19%) after 2010. It was highest in meningitis caused by Listeria monocytogenes at 27% (95% CI, 24%-31%) and pneumococci at 24% (95% CI, 22%-26%), compared with meningitis caused by meningococci at 9% (95% CI, 8%-10%) or H influenzae at 11% (95% CI, 10%-13%). Meta-regression showed decreasing case fatality ratios overall and stratified by S pneumoniae, Escherichia coli, or Streptococcus agalactiae (P < .001).

Conclusions and Relevance

In this meta-analysis with meta-regression, declining case fatality ratios of community-acquired bacterial meningitis throughout the last century were observed, but a high burden of disease remained.

[Community-Acquired Bacterial Meningoencephalitis: The New Guideline]

Updating the vaccination recommendations against meningococci and pneumococci, in particular the introduction of the B vaccine as the standard vaccination for infants from January 2024 and the adaptation of the pneumococcal vaccination strategy for infants and adults aged 60 and over with the latest conjugate vaccines (PCV13, PCV15, PCV20).Emphasis on the need for rapid diagnostic lumbar puncture and simultaneous serum and cerebrospinal fluid analysis to increase diagnostic precision. The introduction of procalcitonin (PCT) in serum as an additional biomarker to differentiate between bacterial and viral meningitis.The use of multiplex PCR as a supplement, not a replacement, for standard diagnostics to speed up pathogen identification.Adaptation of antibiotic recommendations based on the current resistance situation, in particular for meningococcal meningitis, consideration of penicillin G only after resistance testing.Clarification of the areas and duration of use of dexamethasone in bacterial meningitis, particularly in pneumococcal meningitis and the controversial data situation in Listeria meningitis.New findings on the safe use of heparin in septic sinus thrombosis without increased risk of hemorrhage.

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.

Effect of the COVID-19 pandemic on clinical characteristics and outcomes of adult pneumococcal meningitis patients - a Dutch prospective nationwide cohort study

PURPOSE

To investigate clinical characteristics and outcomes of patients with pneumococcal meningitis during the COVID-19 pandemic.

METHODS

In a Dutch prospective cohort, risk factors and clinical characteristics of pneumococcal meningitis episodes occurring during the COVID-19 pandemic (starting March 2020) were compared with those from baseline and the time afterwards. Outcomes were compared with an age-adjusted logistic regression model.

RESULTS

We included 1,699 patients in 2006-2020, 50 patients in 2020-2021, and 182 patients in 2021-2023. After March 2020 relatively more alcoholism was reported (2006-2020, 6.1%; 2020-2021, 18%; 2021-2023, 9.7%; P = 0.002) and otitis-sinusitis was less frequently reported (2006-2020, 45%; 2020-2021, 22%; 2021-2023, 47%; P = 0.006). Other parameters, i.e. age, sex, symptom duration or initial C-reactive protein level, remained unaffected. Compared to baseline, lumbar punctures were more frequently delayed (on admission day, 2006-2020, 89%; 2020-2021, 74%; 2021-2022, 86%; P = 0.002) and outcomes were worse ('good recovery', 2020-2021, OR 0.5, 95% CI 0.3-0.8).

CONCLUSION

During the COVID-19 pandemic, we observed worse outcomes in patients with pneumococcal meningitis. This may be explained by differing adherence to restrictions according to risk groups or by reduced health care quality.

Bacterial load in cerebrospinal fluid predicts unfavourable outcome in pneumococcal meningitis: a prospective nationwide cohort study

OBJECTIVES

The objective of this study was to determine the role of cerebrospinal fluid (CSF) bacterial load in adults with pneumococcal meningitis.

METHODS

We quantified bacterial load in CSF samples from the diagnostic lumbar puncture of adults with community-acquired pneumococcal meningitis. We also measured CSF concentrations of complement component 5a (C5a), and determined associations between bacterial load, clinical characteristics, C5a and unfavourable outcome (Glasgow Outcome Scale score <5).

RESULTS

Bacterial load was quantified in 152 CSF samples. Median age of these patients was 61 years (interquartile range [IQR] 51-68), and 69 of 152 (45%) were female. Median CSF bacterial load was 1.6 × 104 DNA copies/mL (IQR 3.4 × 103-1.2 × 105), and did not correlate with CSF white cell count nor with CSF protein concentrations. Median CSF C5a concentration was 35.8 mg/L (IQR 15.9-105.6), and was moderately correlated with CSF bacterial loads (Spearman's rho = 0.42; p < 0001). High bacterial loads were associated with development of complications, such as circulatory shock (OR per logarithmic increase: 2.4, 95% CI: 2.0-2.9; p < 0.001) and cerebrovascular complications [OR: 1.9, 95% CI: 1.6-2.3; p < 0.001]). High bacterial loads were also associated with unfavourable outcome (OR: 2.8, 95% CI: 2.4-3.3; p < 0.001) and death (OR: 3.1, 95% CI: 2.6-3.8; p < 0.001). In a multivariable regression model including age, immunocompromised state, extrameningeal infection focus, admission Glasgow Coma Scale score and CSF C5a concentration, CSF bacterial load remained an independent predictor of unfavourable outcome (adjusted OR: 2.5, 95% CI: 1.6-3.9; p < 0.001).

DISCUSSION

High CSF bacterial load predicts the development of complications and unfavourable outcome in adults with pneumococcal meningitis.

Neuroinfectious Emergencies

OBJECTIVE

This article describes nervous system infections and complications that lead to neurologic emergencies.

LATEST DEVELOPMENTS

New research on the use of dexamethasone in viral and fungal infections is reviewed. The use of advanced MRI techniques to evaluate nervous system infections is discussed.

ESSENTIAL POINTS

Neurologic infections become emergencies when they lead to a rapid decline in a patient's function. Emergent complications may result from neurologic infections that, if not identified promptly, can lead to permanent deficits or death. These complications include cerebral edema and herniation, spinal cord compression, hydrocephalus, vasculopathy resulting in ischemic stroke, venous thrombosis, intracerebral hemorrhage, status epilepticus, and neuromuscular respiratory weakness.

Self-Reported Executive Functioning in Young Adult Survivors of Childhood Bacterial Meningitis

OBJECTIVE

This study investigated executive functions (EFs) in young adult survivors of childhood bacterial meningitis (BM). These skills are important for normal development, and their potential vulnerability in early years suggests that childhood BM could affect executive functions in the longer term.

METHOD

The adult self-report Behavior Rating Inventory of Executive Function was administered to 474 young adult survivors of childhood BM who participated in the 20|30 Dutch Postmeningitis study. Average scores were compared to population-norm group scores. Subgroup scores were compared according to causative pathogen and age at onset.

RESULTS

Young adult survivors of childhood BM scored lower on overall metacognition than the age-matched population norm group. Young adult survivors of childhood BM caused by Streptococcus pneumoniae, S. agalactiae, or Escherichia coli had lower scores than cases caused by Neisseria meningitidis. Survivors with age-at-onset below 12 months had a higher (worse) overall EF score than survivors with age-at-onset above 12 months.

CONCLUSIONS

Young adult survivors of childhood BM experience difficulties in EF. However, most of the self-reported EF scores were within the norm. Future studies need to additionally assess EF in adult survivors of childhood BM using performance-based tests.

Austrian syndrome: Report of one case and a systematic review of case reports - new insights

OBJECTIVE

The objective of this review was to gain new insight into the rare condition, Austrian syndrome: the triad of endocarditis, meningitis and pneumonia caused by Streptococcus pneumoniae.

METHODS

A systematic review of case reports was conducted using the PRISMA guideline. Cases were rigorously screened to meet a set of well-defined inclusion criteria. Relevant data was aggregated and reported using descriptive statistics.

RESULTS

Seventy-one cases from 69 case reports were included in the final review. The mean age was 56.5 years with a male-to-female ratio of 2.4:1. Alcoholism was reported in 41% of patients. Altered mental state (69%) and fever (65%) (mean temperature on admission = 38.9°C) were the commonest presenting symptoms. The mean duration of symptoms before presentation to the hospital was 8 days. The aortic valve was most commonly affected (56%). The mean duration of antibiotic therapy was 5.6 weeks. Seventy percent of patients were admitted to the intensive care unit (ICU). Fifty-six percent of patients had valvular surgery. The average length of stay in the hospital was 36.9 days. Mortality was recorded in 28% of patients.

CONCLUSION

Austrian syndrome is rare but deadly. The true incidence is unknown but is commoner in middle-aged men and in alcoholics. Affected patients are usually critically unwell, often requiring ICU admission and prolonged hospital stays. Treatment is aggressive including prolonged courses of antibiotics and often, surgery. Despite these, the case fatality rate is high, with death occurring in over a quarter of patients. Surgery appears to be associated with better prognosis.

Adjunctive treatments for pneumococcal meningitis: a systematic review of experimental animal models

New treatments are needed to improve the prognosis of pneumococcal meningitis. We performed a systematic review on adjunctive treatments in animal models of pneumococcal meningitis in order to identify treatments with the most potential to progress to clinical trials. Studies testing therapy adjunctive to antibiotics in animal models of pneumococcal meningitis were included. A literature search was performed using Medline, Embase and Scopus for studies published from 1990 up to 17 February 2023. Two investigators screened studies for inclusion and independently extracted data. Treatment effect was assessed on the clinical parameters disease severity, hearing loss and cognitive impairment and the biological parameters inflammation, brain injury and bacterial load. Adjunctive treatments were evaluated by their effect on these outcomes and the quality, number and size of studies that investigated the treatments. Risk of bias was assessed with the SYRCLE risk of bias tool. A total of 58 of 2462 identified studies were included, which used 2703 experimental animals. Disease modelling was performed in rats (29 studies), rabbits (13 studies), mice (12 studies), gerbils (3 studies) or both rats and mice (1 study). Meningitis was induced by injection of Streptococcus pneumoniae into the subarachnoid space. Randomization of experimental groups was performed in 37 of 58 studies (64%) and 12 studies (12%) were investigator-blinded. Overall, 54 treatment regimens using 46 adjunctive drugs were evaluated: most commonly dexamethasone (16 studies), daptomycin (5 studies), complement component 5 (C5; 3 studies) antibody and Mn(III)tetrakis(4-benzoicacid)porphyrin chloride (MnTBAP; 3 studies). The most frequently evaluated outcome parameters were inflammation [32 studies (55%)] and brain injury [32 studies (55%)], followed by disease severity [30 studies (52%)], hearing loss [24 studies (41%)], bacterial load [18 studies (31%)] and cognitive impairment [9 studies (16%)]. Adjunctive therapy that improved clinical outcomes in multiple studies was dexamethasone (6 studies), C5 antibodies (3 studies) and daptomycin (3 studies). HMGB1 inhibitors, matrix metalloproteinase inhibitors, neurotrophins, antioxidants and paquinimod also improved clinical parameters but only in single or small studies. Evaluating the treatment effect of adjunctive therapy was complicated by study heterogeneity regarding the animal models used and outcomes reported. In conclusion, 24 of 54 treatment regimens (44%) tested improved clinically relevant outcomes in experimental pneumococcal meningitis but few were tested in multiple well-designed studies. The most promising new adjunctive treatments are with C5 antibodies or daptomycin, suggesting that these drugs could be tested in clinical trials.

Bacterial Infections in Intensive Care Units: Epidemiological and Microbiological Aspects

Intensive care units constitute a critical setting for the management of infections. The patients' fragilities and spread of multidrug-resistant microorganisms lead to relevant difficulties in the patients' care. Recent epidemiological surveys documented the Gram-negative bacteria supremacy among intensive care unit (ICU) infection aetiologies, accounting for numerous multidrug-resistant isolates. Regarding this specific setting, clinical microbiology support holds a crucial role in the definition of diagnostic algorithms. Eventually, the complete patient evaluation requires integrating local epidemiological knowledge into the best practice and the standardization of antimicrobial stewardship programs. Clinical laboratories usually receive respiratory tract and blood samples from ICU patients, which express a significant predisposition to severe infections. Therefore, conventional or rapid diagnostic workflows should be modified depending on patients' urgency and preliminary colonization data. Additionally, it is essential to complete each microbiological report with rapid phenotypic minimum inhibitory concentration (MIC) values and information about resistance markers. Microbiologists also help in the eventual integration of ultimate genome analysis techniques into complicated diagnostic workflows. Herein, we want to emphasize the role of the microbiologist in the decisional process of critical patient management.

Diagnostic accuracy of clinical and laboratory characteristics in suspected non-surgical nosocomial central nervous system infections

BACKGROUND

The diagnosis of meningitis in non-surgical hospitalized patients is often difficult and diagnostic accuracy of clinical, laboratory, and radiological characteristics is unknown.

AIM

To assess diagnostic accuracy for individual clinical characteristics of patients suspected of non-surgical nosocomial central nervous system (CNS) infections.

METHODS

In a prospective multi-centre cohort study in the Netherlands with adults suspected of CNS infections, consecutive patients who underwent a lumbar puncture for the suspicion of a non-surgical nosocomial CNS infection were included. All episodes were categorized into five final clinical diagnosis categories, as reference standard: CNS infection, CNS inflammatory disease, systemic infection, other neurological disease, or non-systemic, non-neurological disease.

FINDINGS

Between 2012 and 2022, 114 out of 1275 (9%) patients included in the cohort had suspected non-surgical nosocomial CNS infection: 16 (14%) had a confirmed diagnosis, including four (25%) with bacterial meningitis, nine (56%) with viral CNS infections, two (13%) fungal meningitis, and one (6%) parasitic meningitis. Diagnostic accuracy of individual clinical characteristics was generally low. Elevated CSF leucocyte count had the highest sensitivity (81%; 95% confidence interval (CI): 54-96) and negative predictive value (NPV) (96%; 95% CI: 90-99). When combining the presence of abnormalities in neurological or CSF examination, sensitivity for diagnosing a CNS infection was 100% (95% CI: 79-100) and NPV 100% (95% CI: 78-100). CSF examination changed clinical management in 47% of patients.

CONCLUSION

Diagnostic accuracy for individual clinical characteristics was low, with elevated CSF leucocyte count having the highest sensitivity and NPV.

Characterization and diagnosis spectrum of patients with cerebrospinal fluid pleocytosis

PURPOSE

There is an overlap in the cerebrospinal fluid (CSF) characteristics of patients presenting with different etiologies of CSF pleocytosis. Here, we characterized patients with CSF pleocytosis treated in a large hospital.

METHODS

A retrospective cohort study of 1150 patients with an elevated CSF leukocyte count > 5 cells/µl treated at a university hospital in Germany from January 2015 to December 2017 was performed. Information on clinical presentation, laboratory parameters, diagnosis and outcome was collected. Clinical and laboratory features were tested for their potential to differentiate between bacterial meningitis (BM) and other causes of CSF pleocytosis.

RESULTS

The most common etiologies of CSF pleocytosis were CNS infections (34%: 20% with detected pathogen, 14% without), autoimmune (21%) and neoplastic diseases (16%). CSF cell count was higher in CNS infections with detected pathogen (median 82 cells/µl) compared to autoimmune (11 cells/µl, p = 0.001), neoplastic diseases (19 cells/µl, p = 0.01) and other causes (11 cells/µl, p < 0.001). The CHANCE score was developed to differentiate BM from other causes of CSF pleocytosis: Multivariate regression revealed that CSF cell count > 100 cells/µl, CSF protein > 100 mg/dl, CRP > 5 mg/dl, elevated white blood cell count, abnormal mental status and nuchal rigidity are important indicators. The CHANCE score identified patients with BM with high sensitivity (92.1%) and specificity (90.9%) (derivation cohort: AUC: 0.955, validation cohort: AUC: 0.956).

CONCLUSION

Overall, the most common causes for CSF pleocytosis include infectious, neoplastic or autoimmune CNS diseases in ~ 70% of patients. The CHANCE score could be of help to identify patients with high likelihood of BM and support clinical decision making.

Metagenomic next-generation sequencing for diagnosis of infectious encephalitis and meningitis: a retrospective study of 90 patients

BACKGROUND

Infections of the central nervous system (CNS) are potentially life-threatening and can cause serious morbidity. We evaluated the clinical value of metagenomic next-generation sequencing (mNGS) in the diagnosis of infectious encephalitis and meningitis and explored the factors affecting the results of mNGS.

METHODS

Patients with suspected cases of encephalitis or meningitis who presented in Northern Jiangsu People's Hospital from 1 March 2018 to 30 September 2022 were collected. Demographic, historical, and clinical information were obtained, and cerebrospinal fluid (CSF) samples were treated with mNGS. The pathogen was identified using National Center for Biotechnology Information (NCBI) GenBank sequence data.

RESULTS

Ninety-six patients were screened and finally 90 subjects enrolled. Of the 90 enrolled cases, 67 (74.4%) were diagnosed with central nervous system infections, which included 48 cases (71.6%) of viral infection, 11 (12.2%) of bacterial infection, 5 (7.5%) of mycobacterium tuberculosis, 2 (3.0%) of fungal infection, and 1 (1.5%) of rickettsia infection. From these cases, mNGS identified 40 (44.4%) true-positive cases, 3 (3.3%) false-positive case, 22 (24.4%) true-negative cases, and 25 (27.8%) false-negative cases. The sensitivity and specificity of mNGS were 61.5% and 88%, respectively. mNGS of CSF could show a higher positive rate in patients with marked CSF abnormalities, including elevated protein concentrations and monocyte counts.

CONCLUSION

mNGS of CSF is an effective method for detecting infectious encephalitis and meningitis, and the results should be analyzed combined with conventional microbiological testing results.

Impact of direct ICU admission of pneumococcal meningitis in France: a retrospective analysis of a French medico-administrative (PMSI) database

BACKGROUND

Current guidelines for adult patients with pneumococcal meningitis (PM) recommend initial management in intermediate or intensive care units (ICU), but evidence to support these recommendations is limited. We aimed to describe ICU admission practices of patients with PM.

METHODS

We conducted a retrospective analysis of the French medico administrative database of consecutive adult patients with PM and sepsis criteria hospitalized between 2011 and 2020. We defined two groups, "Direct ICU" corresponding to a direct ICU admission and "Delayed ICU" corresponding to a secondary ICU admission.

RESULTS

We identified 4052 patients hospitalized for a first episode of PM, including 2006 "Direct ICU" patients (50%) and 2046 "delayed ICU" patients (50%). The patients were mainly males [n = 2260 (56%)] with median age of 61 years [IQR 50-71] and a median Charlson index of 1 [0-3]. Among them, median SAPS II on admission was 46 [33-62], 2173 (54%) had a neurological failure on admission with 2133 (53%) in coma, 654 (16%) with brainstem failure, 488 (12%) with seizures and 779 (19%) with focal signs without coma. PM was frequently associated with pneumonia [n = 1411 (35%)], and less frequently with endocarditis [n = 317 (8%)]. The median ICU length of stay and hospital length of stay were 6 days [2-14] and 21 days [13-38], respectively. In-hospital mortality was 27% (n = 1100) and 640 (16%) patients were secondarily transferred to rehabilitation care unit. Direct ICU group was significantly more severe but after adjustment for age, sex, comorbidities, organ failures on admission and admission from home, direct ICU admission was significantly associated with a lower mortality (Odds ratio 0.67 [0.56-0.80], p < 0.01). This corresponded to one death avoided for 11 PM directly admitted in ICU.

CONCLUSIONS

Among patients with PM and sepsis, direct ICU admission was associated with lower mortality rates when compared to delayed admission.

NLRP3 Activation Contributes to Memory Impairment in an Experimental Model of Pneumococcal Meningitis

Bacterial meningitis is considered a life-threatening condition with high mortality rates. In response to the infection, signaling cascades, producing pro-inflammatory mediators trigger an exacerbated host immune response. Another inflammatory pathway occurs through the activation of inflammasomes. Studies highlight the role of the NLR family pyrin domain containing 3 (NLRP3) in central nervous system disorders commonly involved in neuroinflammation. We aimed to investigate the role of NLRP3 and its inhibitor MCC950 on neurochemical, immunological, and behavioral parameters in the early and late stages of experimental pneumococcal meningitis. For this, adult male Wistar rats received an intracisternal injection of Streptococcus pneumoniae or artificial cerebrospinal fluid as a placebo. The animals were divided into control/saline, control/MCC950, meningitis/saline, and meningitis/MCC950. Immediately after the meningitis induction, the animals received 140 ng/kg MCC950 via intracisternal injection. For the acute protocol, 24 h after induction, brain structures were collected to evaluate cytokines, NLRP3, and microglia. In the long-term group, the animals were submitted to open field and recognition of new objects tests at ten days after the meningitis induction. After the behavioral tests, the same markers were evaluated. The animals in the meningitis group at 24 h showed increased levels of cytokines, NLRP3, and IBA-1 expression, and the use of the MCC950 significantly reduced those levels. Although free from infection, ten days after meningitis induction, the animals in the meningitis group had elevated cytokine levels and demonstrated behavioral deficits; however, the single dose of NLRP3 inhibitor rescued the behavior deficits and decreased the brain inflammatory profile.

Recurrent bacterial meningitis in children in the Netherlands: a nationwide surveillance study

OBJECTIVES

This study aimed to estimate the recurrence rate of culture-positive bacterial meningitis in children in the Netherlands.

DESIGN

Nationwide surveillance study, using the database of the Netherlands Reference Laboratory for Bacterial Meningitis to identify patients with culture-positive bacterial meningitis during childhood.

SETTING

The study was based in the Netherlands.

PARTICIPANTS

A total of 9731 children with a first bacterial meningitis episode between 1 July 1987 and 30 June 2019 were identified.

PRIMARY AND SECONDARY OUTCOME MEASURES

Recurrence was defined as a subsequent episode >28 days, or caused by a different pathogen. Annual incidence and incidence rate ratios (IRRs) comparing the periods 1988-2003 and 2004-2019 were calculated. Predictors of recurrent meningitis were assessed using Cox proportional hazards regression.

RESULTS

Sixty-three (0.6%) of the 9731 children with a first bacterial meningitis episode contracted recurrent meningitis. Neisseria meningitidis was the leading pathogen for first meningitis episodes (52%) and Streptococcus pneumoniae for recurrent episodes (52%). The median annual incidence of first episodes per 100 000 children decreased from 11.81 (IQR 11.26-17.60) in 1988-2003 to 2.60 (IQR 2.37-4.07) in 2004-2019 (IRR 0.25, 95% CI 0.23 to 0.26). The incidence of recurrences did not change: 0.06 (IQR 0.02-0.11) in 1988-2003 to 0.03 (IQR 0.00-0.06) in 2004-2019 (IRR 0.65, 95% CI 0.39 to 1.1). Age above 5 years (OR 3.6 (95% CI 1.5 to 8.3)) and a first episode due to Escherichia coli (OR 25.7 (95% CI 7.2 to 92.0)) were associated with higher risks of recurrence.

CONCLUSION

The recurrence rate of childhood bacterial meningitis in the Netherlands was 0.6%. While the incidence rate of first episodes decreased substantially, this was not the case for recurrent episodes. Older age and a first episode due to E. coli were associated with higher recurrence risks.

Pre-hospital symptoms associated with acute bacterial meningitis differs between children and adults

Community acquired bacterial meningitis (CABM) is a medical emergency requiring timely appropriate action. More knowledge about pre-hospital symptoms is needed. Retrospective observational study of pre-hospital management in patients with CABM between 2016 and 2021 admitted to a hospital in the Capital Region of Denmark. Reported symptoms were extracted from archived audio files of the initial phone call to emergency medical service. The majority of the 209 patients (82%) were adults. The most common symptoms were altered mental state (58%) and fever (57%), while neck stiffness was less common (9%). Children more often presented with fever, fatigue, rashes, and neck stiffness, while adults more often presented with altered mental state, and leg pain. Most patients (85%) reported at least 1 of the 3 symptoms in the classical triad of meningitis, while 3% reported all 3. Children more often presented at least 2 of 3 symptoms in the triad. One child (3%) and 7 adults (4%) received antibiotics pre-admission. Patients with CABM reported a variety of symptoms that differed significantly in children and adults. The classic triad was rare. Very few patients received antibiotics pre-admission. We suggest that questioning relevant symptoms should be done in febrile or mentally altered patients.

Characteristics and prognostic factors of bacterial meningitis in the intensive care unit: a prospective nationwide cohort study

BACKGROUND

Patients with bacterial meningitis can be severely ill necessitating intensive care unit (ICU) treatment. Here, we describe clinical features and prognostic factors of adults with bacterial meningitis admitted to the ICU in a nationwide prospective cohort study.

METHODS

We prospectively assessed clinical features and outcome of adults (age > 16 years) with community-acquired bacterial meningitis included in the MeninGene study between March 1, 2006 and July 1, 2022, that were initially admitted to the ICU. We identified independent predictors for initial ICU admission and for unfavourable outcome (Glasgow Outcome Scale score between 1-4) by multivariable logistic regression.

RESULTS

A total of 2709 episodes of bacterial meningitis were included, of which 1369 (51%) were initially admitted to the ICU. We observed a decrease in proportion of patients being admitted to the ICU during the Covid-19 pandemic in 2020 (decreased to 39%, p = 0.004). Median age of the 1369 patients initially admitted to the ICU was 61 years (IQR 49-69), and the rates of unfavourable outcome (47%) and mortality (22%) were high. During the Covid-19 pandemic, we observed a trend towards an increase in unfavourable outcome. Prognostic factors predictive for initial ICU admission were younger age, immunocompromised state, male sex, factors associated with pneumococcal meningitis, and those indicative of systemic compromise. Independent predictors for unfavourable outcome in the initial ICU cohort were advanced age, admittance to an academic hospital, cranial nerve palsies or seizures on admission, low leukocyte count in blood, high C-reactive protein in blood, low CSF: blood glucose ratio, listerial meningitis, need for mechanical ventilation, circulatory shock and persistent fever. 204 of 1340 episodes (15%) that were initially not admitted to the ICU were secondarily transferred to the ICU. The rates of unfavourable outcome (66%) and mortality (30%) in this group were high.

CONCLUSIONS

The majority of patients with community-acquired bacterial meningitis are admitted to the ICU, and the unfavourable outcome and mortality rates of these patients remain high. Patients that are initially admitted to non-ICU wards but secondarily transferred to the ICU also had very high rates of unfavourable outcome.

Predictors of unfavourable outcome in adults with suspected central nervous system infections: a prospective cohort study

Suspected central nervous system (CNS) infections may pose a diagnostic challenge, and often concern severely ill patients. We aim to identify predictors of unfavourable outcome to prioritize diagnostics and treatment improvements. Unfavourable outcome was assessed on the Glasgow Outcome Scale at hospital discharge, defined by a score of 1 to 4. Of the 1152 episodes with suspected CNS infection, from two Dutch prospective cohorts, the median age was 54 (IQR 37-67), and 563 episodes (49%) occurred in women. The final diagnoses were categorized as CNS infection (N = 358 episodes, 31%), CNS inflammatory disease (N = 113, 10%), non-infectious non-inflammatory neurological disorder (N = 388, 34%), non-neurological infection (N = 252, 22%), and other systemic disorder (N = 41, 4%). Unfavourable outcome occurred in 412 of 1152 (36%), and 99 died (9%). Predictors for unfavourable outcomes included advanced age, absence of headache, tachycardia, altered mental state, focal cerebral deficits, cranial nerve palsies, low thrombocytes, high CSF protein, and the final diagnosis of CNS inflammatory disease (odds ratio 4.5 [95% confidence interval 1.5-12.6]). Episodes suspected of having a CNS infection face high risk of experiencing unfavourable outcome, stressing the urgent need for rapid and accurate diagnostics. Amongst the suspected CNS infection group, those diagnosed with CNS inflammatory disease have the highest risk.

Persistent headaches one year after bacterial meningitis: prevalence, determinants and impact on quality of life

BACKGROUND

Little is known on headaches long-term persistence after bacterial meningitis and on their impact on patients' quality of life.

METHODS

In an ancillary study of the French national prospective cohort of community-acquired bacterial meningitis in adults (COMBAT) conducted between February 2013 and July 2015, we collected self-reported headaches before, at onset, and 12 months (M12) after meningitis. Determinants of persistent headache (PH) at M12, their association with M12 quality of life (SF 12), depression (Center for Epidemiologic Studies Depression Scale) and neuro-functional disability were analysed.

RESULTS

Among the 277 alive patients at M12 87/274 (31.8%), 213/271 (78.6%) and 86/277 (31.0%) reported headaches before, at the onset, and at M12, respectively. In multivariate analysis, female sex (OR: 2.75 [1.54-4.90]; p < 0.001), pre-existing headaches before meningitis (OR: 2.38 [1.32-4.30]; p < 0.01), higher neutrophilic polynuclei percentage in the CSF of the initial lumbar puncture (OR: 1.02 [1.00-1.04]; p < 0.05), and brain abscess during the initial hospitalisation (OR: 8.32 [1.97-35.16]; p < 0.01) were associated with M12 persistent headaches. Neither the responsible microorganism, nor the corticoids use were associated with M12 persistent headaches. M12 neuro-functional disability (altered Glasgow Outcome Scale; p < 0.01), M12 physical handicap (altered modified Rankin score; p < 0.001), M12 depressive symptoms (p < 0.0001), and M12 altered physical (p < 0.05) and mental (p < 0.0001) qualities of life were associated with M12 headaches.

CONCLUSION

Persistent headaches are frequent one year after meningitis and are associated with quality of life alteration.

CLINICAL TRIAL

NCT01730690.

Blood-brain barrier dysfunction in intensive care unit

The central nervous system is characterized by a peculiar vascularization termed blood-brain barrier (BBB), which regulates the exchange of cells and molecules between the cerebral tissue and the whole body. BBB dysfunction is a life-threatening condition since its presence corresponds to a marker of severity in most diseases encountered in the intensive care unit (ICU). During critical illness, inflammatory response, cytokine release, and other phenomena activating the brain endothelium contribute to alterations in the BBB and increase its permeability to solutes, cells, nutrients, and xenobiotics. Moreover, patients in the ICU are often old, with underlying acute or chronic diseases, and overly medicated due to their critical condition; these factors could also contribute to the development of BBB dysfunction. An accurate diagnostic approach is critical for the identification of the mechanisms underlying BBB alterations, which should be rapidly managed by intensivists. Several methods were developed to investigate the BBB and assess its permeability. Nevertheless, in humans, exploration of the BBB requires the use of indirect methods. Imaging and biochemical methods can be used to study the abnormal passage of molecules through the BBB. In this review, we describe the structural and functional characteristics of the BBB, present tools and methods for probing this interface, and provide examples of the main diseases managed in the ICU that are related to BBB dysfunction.

Listeria meningitis diagnosed by blood culture with fever, neurological symptoms, and no meningeal irritation signs

Key Clinical Message

Listeria can cause neurological symptoms in immunocompromised and older patients. Additionally, it is impossible to rule out meningitis by the absence of typical meningeal irritation signs. Therefore, patients with fever and neurological impairments should be rapidly examined for blood and cerebrospinal fluid cultures to rule out Listeria meningitis.

Abstract

A woman in her 90s developed fever, dysarthria, and transient disturbance of consciousness. Physical examination revealed no meningeal irritation signs. Listeria monocytogenes were detected in her blood culture the following day. Because of an increased number of cells in cerebrospinal fluid, she was diagnosed with Listeria meningitis.

Clinical features and prognostic factors in adults with viral meningitis

Clinical features applicable to the entire spectrum of viral meningitis are limited, and prognostic factors for adverse outcomes are undetermined. This nationwide population-based prospective cohort study included all adults with presumed and microbiologically confirmed viral meningitis in Denmark from 2015 until 2020. Prognostic factors for an unfavourable outcome (Glasgow Outcome Scale score of 1-4) 30 days after discharge were examined by modified Poisson regression. In total, 1066 episodes of viral meningitis were included, yielding a mean annual incidence of 4.7 episodes per 100 000 persons. Pathogens were enteroviruses in 419/1066 (39%), herpes simplex virus type 2 in 171/1066 (16%), varicella-zoster virus in 162/1066 (15%), miscellaneous viruses in 31/1066 (3%) and remained unidentified in 283/1066 (27%). The median age was 33 years (IQR 27-44), and 576/1066 (54%) were females. In herpes simplex virus type 2 meningitis, 131/171 (77%) were females. Immunosuppression [32/162 (20%)] and shingles [90/149 (60%)] were frequent in varicella-zoster virus meningitis. The triad of headache, neck stiffness and hyperacusis or photophobia was present in 264/960 (28%). The median time until lumbar puncture was 3.0 h (IQR 1.3-7.1), and the median CSF leucocyte count was 160 cells/µl (IQR 60-358). The outcome was unfavourable in 216/1055 (20%) 30 days after discharge. Using unidentified pathogen as the reference, the adjusted relative risk of an unfavourable outcome was 1.34 (95% CI 0.95-1.88) for enteroviruses, 1.55 (95% CI 1.00-2.41) for herpes simplex virus type 2, 1.51 (95% CI 0.98-2.33) for varicella-zoster virus and 1.37 (95% CI 0.61-3.05) for miscellaneous viruses. The adjusted relative risk of an unfavourable outcome was 1.34 (95% CI 1.03-1.75) for females. Timing of acyclovir or valacyclovir was not associated with the outcome in meningitis caused by herpes simplex virus type 2 or varicella-zoster virus. In summary, the outcome of viral meningitis was similar among patients with different aetiologies, including those with presumed viral meningitis but without an identified pathogen. Females had an increased risk of an unfavourable outcome. Early antiviral treatment was not associated with an improved outcome in meningitis caused by herpes simplex virus type 2 or varicella-zoster virus.

German guidelines on community-acquired acute bacterial meningitis in adults

INTRODUCTION

The incidence of community-acquired acute bacterial meningitis has decreased during the last decades. However, outcome remains poor with a significant proportion of patients not surviving and up to 50% of survivors suffering from long-term sequelae. These guidelines were developed by the Deutsche Gesellschaft für Neurologie (DGN) under guidance of the Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF) to guide physicians through diagnostics and treatment of adult patients with acute bacterial meningitis.

RECOMMENDATIONS

The most important recommendations are: (i) In patients with suspected acute bacterial meningitis, we recommend that lumbar cerebrospinal fluid (with simultaneous collection of serum to determine the cerebrospinal fluid-serum glucose index and blood cultures) is obtained immediately after the clinical examination (in the absence of severely impaired consciousness, focal neurological deficits, and/or new epileptic seizures). (ii) Next, we recommend application of dexamethasone and empiric antibiotics intravenously. (iii) The recommended initial empiric antibiotic regimen consists of ampicillin and a group 3a cephalosporin (e.g., ceftriaxone). (iv) In patients with severely impaired consciousness, new onset focal neurological deficits (e.g. hemiparesis) and/or patients with newly occurring epileptic seizures, we recommend that dexamethasone and antibiotics are started immediately after the collection of blood; we further recommend that -if the imaging findings do not indicate otherwise -a lumbar CSF sample is taken directly after imaging. (v) Due to the frequent occurrence of intracranial and systemic complications, we suggest that patients with acute bacterial meningitis are treated at an intensive care unit in the initial phase of the disease. In the case of impaired consciousness, we suggest that this is done at an intensive care unit with experience in the treatment of patients with severe CNS diseases.

CONCLUSIONS

The German S2k-guidelines give up to date recommendations for workup, diagnostics and treatment in adult patients with acute bacterial meningitis.

Worth the risk? Contemporary indications, yield and complications of lumbar punctures in a metropolitan Australian health service

BACKGROUND

Performing lumbar punctures carries a risk of harm to the patient, but the information cerebrospinal fluid provides often makes this procedure necessary. Clinicians in the Australian setting would benefit from having more information on these procedures, in order to help them in a risk versus benefit analysis.

AIMS

To describe the contemporary indications, cerebrospinal fluid findings and complications of lumbar punctures in a metropolitan Australian health service.

METHODS

Retrospective electronic medical records audit of lumbar punctures performed on 525 adults within three acute hospitals between 1 July 2018 and 30 June 2019. Main outcome measures include frequency of indication for lumbar puncture by category, normal versus abnormal cerebrospinal fluid for each category, and frequency, severity and type of complications of lumbar punctures.

RESULTS

Of 525 adult lumbar punctures that were assessed in this study, 466 were performed for a diagnostic indication. The most common diagnostic indications were acute severe headache (156 procedures; 33.5%) and encephalopathy (128 procedures; 27.5%). The yield of abnormal results varied by indication category, with the above indications yielding abnormal results in 85 (54.5%) and 72 (56.3%) cases respectively. A complication was recorded in 54 (10.3% of total) procedures. The majority (45; 8.6%) of complications were minor in severity and most frequently consisted of post-dural puncture headache (PDPH).

CONCLUSIONS

In the era of an increased reliance on high quality neuroimaging, lumbar puncture has a high diagnostic yield with a low rate of major complications. The most common complication is PDPH, which is mild and self-limiting in most cases.

Addition of daptomycin for the treatment of pneumococcal meningitis: protocol for the AddaMAP study

BACKGROUND

The leading cause of acute bacterial meningitis in adults is Streptococcus pneumoniae. This infection is associated with high rates of mortality and morbidity related, among other factors, to the excessive host response to the pneumococcal lysis. Experimental in vitro and in vivo data show that the combination of corticosteroids/third-generation cephalosporins and the non-lytic antibiotic, daptomycin, has synergistic effects with (1) a rapid cerebrospinal fluid sterilisation, (2) less brain damages and (3) less loss of cognitive performances. Despite these encouraging results, daptomycin has never been evaluated in adult patients with pneumococcal meningitis.

METHODS AND ANALYSIS

The AddaMAP trial is a phase II, open-label, Simon's two-stage, multicentre trial that has been designed to assess the efficacy and safety of adding daptomycin (10 mg/kg/d for 8 days) to the recommended treatment (corticosteroids+third generation cephalosporin) in adults with confirmed pneumococcal meningitis. The main endpoint is the disability-free survival (defined as modified Rankin Scale mRS≤2) at day 30. Secondary outcomes are overall mortality, disability at D30 and D90 (mRS, Glasgow Coma Scale and Glasgow Outcome Scales, mini-mental score), hearing loss (Hearing Handicap Inventory Test at D30 and D90, routine audiometric test and Hearing-it test at D30), and quality of life (12-item Short Form Survey and WHO QOL BREF). Seventy-two analysable patients are required.

ETHICS AND DISSEMINATION

The study protocol was approved by the Institutional Review Board of the IDF 1 of the ethics committee on 16 January 2018, and authorisation was obtained from the Agence Nationale de Securité des Médicaments et des Produits de Santé on 22 September 2017. The results will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT03480191.

Escherichia coli Meningitis in a Patient With Urinary Tract Infection: A Case Report

This article discusses a case of Escherichia coli (E. coli) meningitis resulting in altered mental status in a patient with multiple pre-existing comorbidities. The case highlights the underestimated risk of community-acquired gram-negative meningitis in adults, which can have a high mortality rate, particularly in elderly patients with sepsis and urinary tract infections. Diagnosis of E. coli meningitis was confirmed by analyzing cerebrospinal fluid obtained through the lumbar puncture and blood cultures. Treatment involved prompt administration of antibiotics and supportive care. However, the emergence of antibiotic resistance, such as extended-spectrum beta-lactamase production, in community-acquired E. coli meningitis is an increasing concern. Therefore, early recognition and appropriate management are crucial in the diagnosis and treatment of this life-threatening condition.

Epidemiology, clinical features and outcome of adults with meningococcal meningitis: a 15-year prospective nationwide cohort study

Background

We describe the epidemiology, clinical features and outcome of adult meningococcal meningitis in the Netherlands over a 15-year period.

Methods

We studied adults (age ≥ 16 years) who were listed by the Netherlands Reference Laboratory for Bacterial Meningitis and/or included in the prospective nationwide cohort study (MeninGene) between January 2006 and July 2021. Incidences were calculated per epidemiological year (July-June).

Findings

We identified 442 episodes of adult meningococcal meningitis. The median patient age was 32 years (IQR 18-55) and 226 episodes (51%) occurred in female patients. The annual incidence per 100,000 adults fluctuated, from 0.33 in 2006-2007 to 0.05 in 2020-2021, with a temporal increase up to 0.30 from 2016 to 2018, driven by an outbreak of serogroup W (MenW). Of 442 episodes, 274 episodes (62%) in 273 patients were included in the clinical cohort study. The overall case fatality rate was 4% (10 of 274) and 16% (43 of 274) had an unfavourable outcome (Glasgow Outcome Scale score 1-4). Compared to other serogroups, MenW was associated with higher rates of unfavourable outcome (6 of 16 [38%] vs. 37 of 251 [15%], P = 0.03) and death (4 of 16 [25%] vs. 6 of 251 [2%], P = 0.001).

Interpretation

The overall incidence of adult meningococcal meningitis in the Netherlands is low and outcome is generally favourable. An increase of MenW meningitis occurred from 2016 to 2018, which was associated with more unfavourable outcome and death.

Funding

Netherlands Organisation for Health Research and Development, European Research Council, National Institute of Public Health and Environmental protection.

Klebsiella pneumoniae invasive syndrome with liver abscess and purulent meningitis presenting as acute hemiplegia: a case report

BACKGROUND

Klebsiella pneumoniae can infect a variety of sites, with the risk of infection being higher in the immunocompromised state such as diabetes mellitus. A distinct invasive syndrome has been detected mostly in Southeast Asia in the past two decades. A common destructive complication is pyogenic liver abscess that can be complicated by metastatic endophthalmitis as well as the involvement of the central nervous system, causing purulent meningitis or brain abscess.

CASE PRESENTATION

We report a rare case of an invasive liver abscess caused by K. pneumoniae, with metastatic infections of meninges. A 68-year-old man with type 2 diabetes mellitus presented to our emergency department as sepsis. Sudden disturbed consciousness was noticed with presentation of acute hemiplegia and gaze preference mimicking a cerebrovascular accident.

CONCLUSIONS

The above case adds to the scarce literature on K. pneumoniae invasive syndrome with liver abscess and purulent meningitis. K. pneumoniae is a rare cause of meningitis and should raise suspicions about the disease in febrile individuals. In particular, Asian patients with diabetes presenting with sepsis and hemiplegia prompt a more thorough evaluation with aggressive treatment.

Cerebrovascular complications in patients with community-acquired bacterial meningitis: occurrence and associated factors in the COMBAT multicenter prospective cohort

BACKGROUND

Community-acquired bacterial meningitis is a rare but severe central nervous system infection that may be associated with cerebrovascular complications (CVC). Our objective is to assess the prevalence of CVC in patients with community-acquired bacterial meningitis and to determine the first-48 h factors associated with CVC.

METHODS

We analyzed data from the prospective multicenter cohort study (COMBAT) including, between February 2013 and July 2015, adults with community-acquired bacterial meningitis. CVC were defined by the presence of clinical or radiological signs (on cerebral CT or MRI) of focal clinical symptom. Factors associated with CVC were identified by multivariate logistic regression.

RESULTS

CVC occurred in 128 (25.3%) of the 506 patients in the COMBAT cohort (78 (29.4%) of the 265 pneumococcal meningitis, 17 (15.3%) of the 111 meningococcal meningitis, and 29 (24.8%) of the 117 meningitis caused by other bacteria). The proportion of patients receiving adjunctive dexamethasone was not statistically different between patients with and without CVC (p = 0.84). In the multivariate analysis, advanced age (OR = 1.01 [1.00-1.03], p = 0.03), altered mental status at admission (OR = 2.23 [1.21-4.10], p = 0.01) and seizure during the first 48 h from admission (OR = 1.90 [1.01-3.52], p = 0.04) were independently associated with CVC.

CONCLUSIONS

CVC were frequent during community-acquired bacterial meningitis and associated with advanced age, altered mental status and seizures occurring within 48 h from admission but not with adjunctive corticosteroids.

Factors associated with treatment delay and outcome in community acquired bacterial meningitis

Background

Community acquired bacterial meningitis (CABM) is a condition associated with significant morbidity and mortality. Treatment delay remains an area of concern and might be improved by awareness of meningitis among health care professionals.

Methods

Retrospective observational study of patients with CABM between 2016 and 2021 in Eastern Denmark with a population of 2,700,000. Data was extracted from electronic health records. Treatment delay and mortality was analyzed using multivariate logistic regression and expressed as odds ratio (OR) with 95% confidence intervals (CI).

Results

Of 369 patients 226 (61%) had treatment delayed more than 2 hours. Old age (OR 2.42, CI 1.22;4.77), comorbidity (OR 1.30, CI 1.00;1.70), suspicion of other infections than meningitis (OR 65.93, CI 20.68;210.20), stroke (OR 7.24, CI 3.11;16.86) and other diagnoses (OR 13.00, CI 5.07;33.31) were associated with delayed treatment. Treatment delay was associated with increased 30-day mortality (OR 3.07, 95% CI 1.09;8.67). Most of the treatment delay (82%) was due lack of suspicion of CABM.

Conclusions

Treatment delay is a common problem associated with 30-day mortality in CABM. Awareness of CABM in undiagnosed patients is vital to achieve timely initiation of appropriate treatment. Special care should be shown for patients suspected of stroke or other infections.

A Prospective Observational Study of Children with FS-Associated Hospitalization: The Implication and Outcomes of Pathogen Detection in Cerebrospinal Fluid

Background

Febrile seizures (FS) are a common cause of paediatric emergencies, but research on their aetiology and epidemiology are limited. The aim of this study was to investigate the prevalence of central nervous system (CNS) pathogenic infections in patients with FS-associated hospitalization.

Methods

A prospective observational study was conducted in children under 16 years of age with FS-associated hospitalization. Demographic, clinical and laboratory data were recorded. Multiplex-PCR was performed on cerebrospinal fluid (CSF) samples for nine viruses, nine bacteria and one fungus.

Results

A total of 119 children were enrolled between June 2021 and June 2022. Of these, 83.2% had a final diagnosis of FS (69.7%) or FS plus (13.4%). In addition, epilepsy and encephalitis/meningitis were also found in 16.8% (20/119). Seven pathogens were identified from 9 CSF samples (7.6%), including viruses (EV, EBV, HHV-6) and bacteria (H. influenzae, S. pneumoniae, M. tuberculosis, S. putrefaciens). There were no significant clinical or laboratory differences between children who tested positive or negative for pathogens in the CSF, except for the presentation of herpes pharyngitis. Children with encephalitis/meningitis had longer hospital stays compared with those diagnosed with FS at discharge; abnormal EEG findings were significantly more common in patients with epilepsy.

Conclusion

FS-associated hospitalized children may have viral or bacterial intracranial infections. Pathogen testing of CSF is an important basis for timely antibiotic or antiviral therapy when clinical and laboratory findings make FS indistinguishable from other CNS disorders.

High-risk factors associated with refractory childhood bacterial meningitis in Southwest China

BACKGROUND

Refractory bacterial meningitis is acute, develops rapidly, and has higher mortality and morbidity than common bacterial meningitis. This study was undertaken to investigate the high-risk factors related to refractory bacterial meningitis in children with positive pathogens.

METHODS

We retrospectively analyzed the clinical data of 109 patients who had bacterial meningitis. The patients were divided into a refractory group (96 patients) and nonrefractory group (13 patients) based on the classification criteria. Seventeen clinical variables on risk factors were extracted and evaluated by univariate and multivariate logistic regression analyses.

RESULTS

There were 64 males and 45 females. The onset age ranged from 1 month old to 12 years old, and the median age was 181 days old. The pathogenic bacteria included 67 cases of gram-positive (G+) bacteria (61.5%) and 42 cases of gram-negative (G-) bacteria. In patients who were 1 to 3 months old, E. coli was the most common (47.5%), followed by Streptococcus agalactiae and Staphylococcus hemolyticus (10.0%); in patients > 3 months old, S. pneumoniae was the most common (55.1%), followed by E. coli (8.7%). The multivariate analysis indicated that consciousness disorder (odds ratio [OR] = 13.050), peripheral blood C-reactive protein (CRP) ≥ 50 mg/L (OR = 29.436), and the isolate bacteria being gram-positive bacteria (OR = 8.227) were independent risk factors for predicting who would progress to refractory bacterial meningitis in this group.

CONCLUSION

For patients who have pathogenic positive bacterial meningitis along with consciousness disorder, CRP ≥ 50 mg/L, and/or have an isolate bacteria that is a G + bacteria, it is important to be alert to the potential for progression to refractory bacterial meningitis, which demands the physicians' significant attention.

Clinical features, etiologies, and outcomes in adult patients with meningoencephalitis requiring intensive care (EURECA): an international prospective multicenter cohort study

PURPOSE

We aimed to characterize the outcomes of patients with severe meningoencephalitis requiring intensive care.

METHODS

We conducted a prospective multicenter international cohort study (2017-2020) in 68 centers across 7 countries. Eligible patients were adults admitted to the intensive care unit (ICU) with meningoencephalitis, defined by an acute onset of encephalopathy (Glasgow coma scale (GCS) score [Formula: see text] 13), a cerebrospinal fluid pleocytosis [Formula: see text] 5 cells/mm3, and at least two of the following criteria: fever, seizures, focal neurological deficit, abnormal neuroimaging, and/or electroencephalogram. The primary endpoint was poor functional outcome at 3 months, defined by a score of three to six on the modified Rankin scale. Multivariable analyses stratified on centers investigated ICU admission variables associated with the primary endpoint.

RESULTS

Among 599 patients enrolled, 589 (98.3%) completed the 3-month follow-up and were included. Overall, 591 etiologies were identified in those patients which were categorized into five groups: acute bacterial meningitis (n = 247, 41.9%); infectious encephalitis of viral, subacute bacterial, or fungal/parasitic origin (n = 140, 23.7%); autoimmune encephalitis (n = 38, 6.4%); neoplastic/toxic encephalitis (n = 11, 1.9%); and encephalitis of unknown origin (n = 155, 26.2%). Overall, 298 patients (50.5%, 95% CI 46.6-54.6%) had a poor functional outcome, including 152 deaths (25.8%). Variables independently associated with a poor functional outcome were age > 60 years (OR 1.75, 95% CI 1.22-2.51), immunodepression (OR 1.98, 95% CI 1.27-3.08), time between hospital and ICU admission > 1 day (OR 2.02, 95% CI 1.44-2.99), a motor component on the GCS [Formula: see text] 3 (OR 2.23, 95% CI 1.49-3.45), hemiparesis/hemiplegia (OR 2.48, 95% CI 1.47-4.18), respiratory failure (OR 1.76, 95% CI 1.05-2.94), and cardiovascular failure (OR 1.72, 95% CI 1.07-2.75). In contrast, administration of a third-generation cephalosporin (OR 0.54, 95% CI 0.37-0.78) and acyclovir (OR 0.55, 95% CI 0.38-0.80) on ICU admission were protective.

CONCLUSION

Meningoencephalitis is a severe neurologic syndrome associated with high mortality and disability rates at 3 months. Actionable factors for which improvement could be made include time from hospital to ICU admission, early antimicrobial therapy, and detection of respiratory and cardiovascular complications at admission.

Adjunctive dexamethasone treatment in adults with listeria monocytogenes meningitis: a prospective nationwide cohort study

Background

A French cohort study described a detrimental effect of adjunctive dexamethasone treatment in listeria meningitis. Based on these results guidelines recommend not to use dexamethasone if L. monocytogenes is suspected or stop dexamethasone when the pathogen is detected. We studied clinical characteristics, treatment regimens and outcome of adults with Listeria monocytogenes meningitis in a nationwide cohort study on bacterial meningitis.

Methods

We prospectively assessed adults with community-acquired L. monocytogenes meningitis in the Netherlands between Jan 1, 2006, and July 1, 2022. We identified independent predictors for an unfavourable outcome (Glasgow Outcome Scale score 1 to 4) and mortality by logistic regression.

Findings

162 out of 2664 episodes (6%) of community-acquired bacterial meningitis episode were caused by L. monocytogenes in 162 patients. Adjunctive dexamethasone 10 mg QID was started with the first dose of antibiotics in 93 of 161 patients (58%) and continued for the full four days in 83 (52%) patients. Different doses, duration or timing of dexamethasone were recorded in 11 patients (7%) and 57 patients (35%) did not receive dexamethasone. The case fatality rate was 51 of 162 (31%) and an unfavourable outcome occurred in 91 of 162 patients (56%). Age and the standard regimen of adjunctive dexamethasone were independent predictors for an unfavourable outcome and mortality. The adjusted odds ratio of dexamethasone treatment for unfavourable outcome was 0.40 (95% confidence interval 0.19-0.81).

Interpretation

Adjunctive dexamethasone is associated with an improved outcome in patients with L. monocytogenes meningitis and should not be withheld if L. monocytogenes is suspected or detected as causative pathogen.

Funding

European Research Council and Netherlands Organisation for Health Research and Development.

The Diagnostic Value of Cerebrospinal Fluid Lactate for Detection of Sepsis in Community-Acquired Bacterial Meningitis

Community-acquired bacterial meningitis conveys significant morbidity and mortality due to intracranial and systemic complications, and sepsis is a major contributor to the latter. While cerebrospinal fluid (CSF) analysis is essential in the diagnosis of bacterial meningitis, its predictive utility for detection of sepsis is unknown. We investigated the diagnostic performance of CSF parameters for sepsis defined by the Sepsis-3 criteria in a retrospective cohort of patients with community-acquired bacterial meningitis. Among 103 patients, 69.5% developed sepsis. CSF lactate was associated with sepsis with an odds ratio of 1.11 (p = 0.022), while CSF cell counts, glucose and protein levels were not (all p > 0.4). Employing the optimal cutoff of 8.2 mmol/L, elevated CSF lactate resulted in a sensitivity of 81.5% and specificity of 61.5% for sepsis. In exploratory analyses, CSF lactate was also associated with in-hospital mortality with an odds ratio of 1.21 (p = 0.011). Elevated CSF lactate might contribute to early diagnosis of sepsis as well as prognostication in patients with community-acquired bacterial meningitis.

Risk factors and pathogen characteristics associated with unfavorable outcomes among adults with pneumococcal meningitis in Japan, 2006 to 2016

PURPOSE

In this study, we aimed to clarify the risk factors associated with unfavorable outcomes in adults with pneumococcal meningitis (PnM).

METHODS

Surveillance was conducted between 2006 and 2016. Adults with PnM (n = 268) were followed up for outcomes within 28 days after admission using the Glasgow Outcome Scale (GOS). After classifying the patients into the unfavorable (GOS1-4) and favorable (GOS5) outcome groups, i) the underlying diseases, ii) biomarkers at admission, and iii) serotype, genotype, and antimicrobial susceptibility for all isolates were compared between both groups.

RESULTS

Overall, 58.6% of patients with PnM survived,15.3% died, and 26.1% had sequelae. The number of living days in the GOS1 group was highly heterogeneous. Motor dysfunction, disturbance of consciousness, and hearing loss were the commonest sequelae. Of the underlying diseases identified in 68.9% of the PnM patients, liver and kidney diseases were significantly associated with unfavorable outcomes. Of the biomarkers, creatinine and blood urea nitrogen, followed by platelet and C-reactive protein had the most significant associations with unfavorable outcomes. There was a significant difference in the high protein concentrations in the cerebrospinal fluid between the groups. Serotypes 23F, 6C, 4, 23A, 22F, 10A, and 12F were associated with unfavorable outcomes. These serotypes were not penicillin-resistant isolates possessing three abnormal pbp genes (pbp1a, 2x, and 2b), except for 23F. The expected coverage rate of the pneumococcal conjugate vaccine (PCV) was 50.7% for PCV15 and 72.4% for PCV20.

CONCLUSIONS

In the introduction of PCV for adults, the risk factors for underlying diseases should be prioritized over age, and serotypes with unfavorable outcomes should be considered.

Pentraxin 3 in the cerebrospinal fluid during central nervous system infections: A retrospective cohort study

The present study describes diagnostic and prognostic abilities of Cerebrospinal fluid (CSF) Pentraxin 3 (PTX3) in central nervous system (CNS) infections. CSF PTX3 was measured retrospectively from 174 patients admitted under suspicion of CNS infection. Medians, ROC curves and Youdens index was calculated. CSF PTX3 was significantly higher among all CNS infections and undetectable in most of the patients in the control group, and significantly higher in bacterial infections compared to viral and Lyme infections. No association was found between CSF PTX3 and Glasgow Outcome Score. PTX3 in the CSF can distinguish bacterial infection from viral and Lyme infections and non-CNS infections. Highest levels were found in bacterial meningitis. No prognostic abilities were found.

High risk and low prevalence diseases: Adult bacterial meningitis

INTRODUCTION

Acute bacterial meningitis in adults is a rare but serious condition that carries a high rate of morbidity.

OBJECTIVE

This review highlights pearls and pitfalls of acute bacterial meningitis in adults, including presentation, diagnosis, and management in the emergency department (ED) based on current evidence.

DISCUSSION

Meningitis encompasses a broad spectrum of disease involving inflammation of the meninges and subarachnoid space. It classically presents with fever, nuchal rigidity, and altered mental status, but this triad is not present in all cases. Up to 95% of patients will have at least two of the following four cardinal symptoms: fever, nuchal rigidity, altered mental status, and headache. The most common bacterial etiologies are S. pneumoniae and N. meningitidis. Cerebrospinal fluid testing obtained by lumbar puncture remains the gold standard in diagnosis. Head computed tomography prior to lumbar puncture may not be necessary in most patients. Empiric treatment consists of vancomycin, ceftriaxone, and dexamethasone. Elevated intracranial pressure should be managed using established neurocritical care strategies.

CONCLUSION

A better understanding of the pearls and pitfalls of acute bacterial meningitis can assist emergency clinicians in pursuing its timely diagnosis and management.

Noninvasive intracranial pressure monitoring in central nervous system infections

Intracranial pressure (ICP) monitoring constitutes an important part of the management of traumatic brain injury. However, its application in other brain pathologies such as neuroinfections like acute bacterial meningitis is unclear. Despite focus on aggressive, prompt treatment, morbidity and mortality from acute bacterial meningitis remain high. Increased ICP is well-known to occur in severe neuroinfections. The increased ICP compromise cerebral perfusion pressure and may ultimately lead to brain stem herniation. Therefore, controlling the ICP could also be important in acute bacterial meningitis. However, risk factors for complications due to invasive monitoring among these patients may be significantly increased due to higher age and levels of comorbidity compared to the traumatic brain injury patient from which the ICP treatment algorithms are developed. This narrative review evaluates the different modalities of ICP monitoring with the aim to elucidate current status of non-invasive alternatives to invasive monitoring as a decision tool and eventually monitoring. Non-invasive screening using ultrasound of the optical nerve sheath, transcranial doppler, magnetic resonance imaging or preferably a combination of these modalities, provides measurements that can be used as a decision guidance for invasive ICP measurement. The available data do not support the replacement of invasive techniques for continuous ICP measurement in patients with increased ICP. Non-invasive modalities should be taken into consideration in patients with neuroinfections at low risk of increased ICP.

Community-acquired Staphylococcus aureus meningitis in adults

BACKGROUND

Staphylococcus aureus is an uncommon cause of community-acquired bacterial meningitis. We aimed to describe patients with this disease.

METHODS

We evaluated clinical characteristics and outcome of adults with community-acquired S. aureus meningitis from prospective nationwide cohort studies from Denmark (2015-2020) and the Netherlands (2006-2021). Whole genome sequencing of S. aureus isolates was performed to evaluate the potential association between clonal complex and clinical characteristics.

RESULTS

We evaluated 111 episodes of community-acquired S. aureus meningitis: 65 from Denmark and 46 from the Netherlands. The median age was 66 years (interquartile range [IQR] 50-74) and 43 of 111 patients were female (39%). Concomitant infectious foci were found in 95 of 107 patients (89%), most commonly endocarditis (53 of 109 [49%]) and spondylodiscitis (43 of 109 [39%]). The triad of neck stiffness, altered mental status (Glasgow Coma Scale score <14), and fever was present in only 18 of 108 patients (17%). Surgery was performed in 14 of 33 patients (42%) with spondylodiscitis and 26 of 52 (50%) with endocarditis. A favorable outcome (Glasgow Outcome Scale score 5) occurred in 26 of 111 patients (23%), while 39 (35%) died. The most common bacterial clonal complexes (CC) were CC30 (16 [17%]), CC45 (16 [17%]), CC5 (12 [13%], and CC15 (10 [11%]); no associations between CCs and concomitant foci or outcome were found.

CONCLUSIONS

Community-acquired S. aureus meningitis is a severe disease with a high case fatality rate, occurring mainly in patients with concomitant endocarditis or spondylodiscitis.

A risk score for identifying patients at a low risk of bacterial meningitis amongst adults with cerebrospinal fluid leucocytosis and a negative gram stain result: a derivation and validation study

OBJECTIVES

We aimed to derive and validate a risk score to differentiate patients with bacterial meningitis from those with viral meningitis or encephalitis amongst patients presenting with cerebrospinal fluid (CSF) leucocytosis and a negative Gram staining result.

METHODS

We included adults with bacterial and viral meningitis or encephalitis presenting with CSF leukocyte counts of >10 per mm³ and a negative Gram staining result from cohorts in Houston, Texas (2004-2019), and the Netherlands (2012-2021). Derivation and the first validation were performed in the American patients and further validation in the Dutch patients.

RESULTS

Derivation was performed in 109 American patients with bacterial meningitis (median age, 56 years; interquartile range [IQR], 46-66 years; 46% women) and 194 with viral meningitis or encephalitis (median age, 46 years; IQR, 33-60 years; 53% women). Serum leukocyte counts of >10.0 × 10⁹/L, CSF leukocyte counts of >2000 per mm³, granulocyte counts of >1180 per mm³, protein levels of >2.2 g/L, glucose levels of <1.9 mmol/L and fever on admission were included in the risk score, which was dichotomized into 'low risk' (0 present) and 'high risk' (>0 present). The first validation showed a sensitivity of 100% (95% CI, 96.6-100) and specificity of 34.0% (95% CI, 27.4-41.2). Further validation in 262 Dutch patients with bacterial meningitis (median age, 57 years; IQR 44-70 years; 45% women) and 68 with viral meningitis (median age, 34 years; IQR, 28-45 years; 60% women) showed a sensitivity of 99.6% (95% CI, 97.9-100) and specificity of 41.2% (95% CI, 29.4-53.7).

CONCLUSIONS

Our risk score may be able to rule out bacterial meningitis amongst patients presenting with CSF leucocytosis and a negative Gram staining result. However, it needs prospective testing prior to clinical implementation.

Severe community-acquired Streptococcus pneumoniae bacterial meningitis: clinical and prognostic picture from the intensive care unit

BACKGROUND

Severe community-acquired pneumococcal meningitis is a medical emergency. The aim of the present investigation was to evaluate the epidemiology, management and outcomes of this condition.

METHODS

This was a retrospective, observational and multicenter cohort study. Sixteen Spanish intensive care units (ICUs) were included. Demographic, clinical and microbiological variables from patients with Streptococcus pneumoniae meningitis admitted to ICU were evaluated. Clinical response was evaluated at 72 h after antibiotic treatment initiation, and meningitis complications, length of stay and 30-day mortality were also recorded.

RESULTS

In total, 255 patients were included. Cerebrospinal fluid (CSF) culture was positive in 89.7%; 25.7% were non-susceptible to penicillin, and 5.2% were non-susceptible to ceftriaxone or cefotaxime. The most frequent empiric antibiotic regimen was third-generation cephalosporin (47.5%) plus vancomycin (27.8%) or linezolid (12.9%). A steroid treatment regimen was administered to 88.6% of the patients. Clinical response was achieved in 65.8% of patients after 72 h of antibiotic treatment. Multivariate analysis identified two factors associated with early treatment failure: invasive mechanical ventilation (OR 10.74; 95% CI 3.04-37.95, p < 0.001) and septic shock (OR 1.18; 95% CI 1.03-1.36, p = 0.017). The 30-day mortality rate was 13.7%. Only three factors were independently associated with 30-day mortality: delay in start of antibiotic treatment (OR 18.69; 95% CI 2.13-163.97, p = 0.008), Sepsis-related Organ Failure Assessment (SOFA) score (OR 1.36; 95% CI 1.12-1.66, p = 0.002) and early treatment failure (OR 21.75 (3.40-139.18), p = 0.001). Neurological complications appeared in 124 patients (48.63%).

CONCLUSIONS

Mortality rate in critically ill patients with pneumococcal meningitis is lower than previously reported. Delay in antibiotic treatment following admission is the only amendable factor associated with mortality.

Bacterial meningitis in Africa

Bacterial meningitis differs globally, and the incidence and case fatality rates vary by region, country, pathogen, and age group; being a life-threatening disease with a high case fatality rate and long-term complications in low-income countries. Africa has the most significant prevalence of bacterial meningitis illness, and the outbreaks typically vary with the season and the geographic location, with a high incidence in the meningitis belt of the sub-Saharan area from Senegal to Ethiopia. Streptococcus pneumoniae (pneumococcus) and Neisseria meningitidis (meningococcus) are the main etiological agents of bacterial meningitis in adults and children above the age of one. Streptococcus agalactiae (group B Streptococcus), Escherichia coli, and Staphylococcus aureus are neonatal meningitis's most common causal agents. Despite efforts to vaccinate against the most common causes of bacterial neuro-infections, bacterial meningitis remains a significant cause of mortality and morbidity in Africa, with children below 5 years bearing the heaviest disease burden. The factors attributed to this continued high disease burden include poor infrastructure, continued war, instability, and difficulty in diagnosis of bacterial neuro-infections leading to delay in treatment and hence high morbidity. Despite having the highest disease burden, there is a paucity of African data on bacterial meningitis. In this article, we discuss the common etiologies of bacterial neuroinfectious diseases, diagnosis and the interplay between microorganisms and the immune system, and the value of neuroimmune changes in diagnostics and therapeutics.

Dynamics of community-acquired meningitis syndrome outbreaks in southern France

In southern France, cases of community-acquired meningitis syndrome (CAM) are typically clustered as outbreaks with determinants which remain unknown. This 61-month retrospective investigation in Nîmes and Marseille university hospital laboratories, yielded 2,209/20,779 (10.63%) documented CAM cases caused by 62 different micro-organisms, represented by seasonal viral etiologies (78.8%), including Enterovirus, Herpes Simplex Virus (HSV), and Varicella-Zoster Virus (VZV; 1,620/2,209 = 73.4%). Multi correspondence analysis revealed an association of infection with age and sex, with the risk of infection being relatively higher in young men, as confirmed by Fisher's exact test (p < 10^-3). Bacterial meningitis accounted for 20% of cases, mostly caused by Streptococcus pneumoniae (27.4% of cases), Neisseria meningitidis (12.5%), and Haemophilus influenzae (9.5%) with bacteria/virus coinfection (0.9%), and only six cases of documented fungal meningitis. In total, 62.6% of cases, of which 88.7% were undocumented, arose from 10 outbreaks. 33.2% of undocumented cases were aged >60 years compared to 19.2% of documented cases (p < 0.001), and viral infection was more common in the summer (87.5%) compared to other seasons (72.3%; p < 0.001). Outbreaks most often started in Nîmes and moved eastward toward Marseille at a speed of ~9 km/day, and these dynamics significantly correlated with atmospheric temperature, especially during summer outbreaks. In particular, the incidence of Enterovirus-driven outbreaks correlated with temperature, revealing correlation coefficients of 0.64 in Nîmes and 0.72 in Marseille, and its occurrence in Marseille lagged that in Nîmes by 1-2 weeks. Tracing the dynamics of CAM outbreak during this retrospective investigation in southern France yielded a speed of displacement that correlated with the variation in temperature between both cities, and these results provide clues for the next occurrence of undocumented outbreaks.

Bacterial meningitis in adults: a retrospective study among 148 patients in an 8-year period in a university hospital, Finland

BACKGROUND

Bacterial meningitis (BM) causes significant morbidity and mortality. We investigated predisposing factors, clinical characteristics, spectrum of etiological bacteria, and clinical outcome of community-acquired and nosocomial BM.

METHODS

In this retrospective study we analyzed data of 148 adults (age > 16 years) with BM treated in Turku University Hospital, Southwestern Finland, from 2011 to 2018. Besides culture- or polymerase chain reaction (PCR)-positive cases we also included culture-negative cases with laboratory parameters strongly suggestive of BM and those with meningitis-related findings in imaging. We used Glasgow Outcome Scale (GOS) score 1-4 to determine unfavorable outcome.

RESULTS

The median age of patients was 57 years and 48.6% were male. Cerebrospinal fluid (CSF) culture for bacteria showed positivity in 50 (33.8%) cases, although pre-diagnostic antibiotic use was frequent (85, 57.4%). The most common pathogens in CSF culture were Streptococcus pneumoniae (11, 7.4%), Staphylococcus epidermidis (7, 4.7%), Staphylococcus aureus (6, 4.1%) and Neisseria meningitidis (6, 4.1%). Thirty-nine patients (26.4%) presented with the triad of fever, headache, and neck stiffness. A neurosurgical procedure or an acute cerebral incident prior BM was recorded in 74 patients (50%). Most of the patients had nosocomial BM (82, 55.4%) and the rest (66, 44.6%) community-acquired BM. Ceftriaxone and vancomycin were the most used antibiotics. Causative pathogens had resistances against the following antibiotics: cefuroxime with a frequency of 6.8%, ampicillin (6.1%), and tetracycline (6.1%). The case fatality rate was 8.8% and the additional likelihood of unfavorable outcome 40.5%. Headache, decreased general condition, head computed tomography (CT) and magnetic resonance imaging (MRI), hypertension, altered mental status, confusion, operative treatment, neurological symptoms, pre-diagnostic antibiotic use and oral antibiotics on discharge were associated with unfavorable outcome.

CONCLUSIONS

The number of cases with nosocomial BM was surprisingly high and should be further investigated. The usage of pre-diagnostic antibiotics was also quite high. Headache was associated with unfavorable outcome. The frequency of unfavorable outcome of BM was 40.5%, although mortality in our patients was lower than in most previous studies.