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.

Prospective multicenter evaluation of adherence to the Dutch guideline for children aged 0-16 years with fever without a source-febrile illness in children (FINCH) study.

Evaluation of guidelines in actual practice is a crucial step in guideline improvement. A retrospective evaluation of the Dutch guideline for children with fever without an apparent source (FWS) showed 50% adherence in young infants. We prospectively evaluated adherence to the Dutch guideline and its impact on management in current practice. Prospective observational multicenter cross-sectional study, including children 3 days to 16 years old presented for FWS at one of seven emergency departments in participating secondary and tertiary care hospitals in the Netherlands. Adherence to the Dutch FWS guideline, adapted from the National Institute for Health and Care Excellence (NICE) guideline, was evaluated, and patterns in non-adherence and the impact of non-adherence on clinical outcomes and resource use were explored. Adherence to the guideline was 192/370 (52%). Adherence was lowest in patients categorized as high risk for severe infection (72/187, 39%), compared to the low-risk group (64/73, 88%). Differences in adherence were significant between risk categories (P < 0.001) but not between age categories. In case of non-adherence, less urinalysis, fewer bacterial cultures (blood, urine, and cerebral spinal fluid), and less empirical antibiotic treatment were performed (P < 0.050). Clinical outcomes were not significantly different between the non-adherence and the adherence group, particularly regarding missed severe infections. CONCLUSIONS: We found a high non-adherence rate of 48%, which did not lead to unfavorable clinical outcomes. This substantiates the need for a critical reevaluation of the FWS guideline and its indications for bacterial cultures, viral testing, and antibiotic treatment. WHAT IS KNOWN: • Despite the development of national guidelines, variation in practice is still substantial in the assessment of febrile children to distinguish severe infection from mild self-limiting disease. • Previous retrospective research suggests low adherence to national guidelines for febrile children in practice. WHAT IS NEW: • In case of non-adherence to the Dutch national guideline, similar to the National Institute for Health and Care Excellence (NICE) guideline from the United Kingdom, physicians have used fewer resources than the guideline recommended without increasing missed severe infections.

Pneumococcal Meningitis in Adults: A Prospective Nationwide Cohort Study Over a 20-year Period.

BACKGROUND: The epidemiology and treatment of pneumococcal meningitis has changed with the implementation of conjugate vaccines and the introduction of adjunctive dexamethasone therapy. METHODS: We analyzed episodes of community-acquired pneumococcal meningitis in adults (≥16 years) in the Netherlands, identified by the National Reference Laboratory for Bacterial Meningitis or treating physician between October 1, 1998, and April 1, 2002, and between January 1, 2006, and July 1, 2018. We studied incidence, pneumococcal serotypes, and clinical features. Predictors for unfavorable outcome (Glasgow Outcome Scale score 1-4) were identified in a multivariable logistic regression model. Two physicians independently categorized causes of death as neurological or systemic. RESULTS: There were 1816 episodes in 1783 patients. The incidence of 7- and 10-7-valent pneumococcal conjugate vaccine serotypes decreased (from 0.42 to 0.06, P = .001; from 0.12 to 0.03 episodes per 100 000 population per year, P = .014). Incidence of nonvaccine serotypes increased (from 0.45 to 0.68, P = .005). The use of adjunctive treatment with dexamethasone increased and was administered in 85% of patients in 2018. In-hospital death occurred in 363 episodes (20%) and unfavorable outcome in 772 episodes (43%). Delayed cerebral thrombosis occurred in 29 patients (2%), of whom 15 patients (52%) died. Adjunctive dexamethasone therapy was associated with favorable outcome (adjusted odds ratio 2.27, P < .001), individual pneumococcal serotypes were not. CONCLUSION: Implementation of conjugate vaccines and adjunctive dexamethasone therapy have changed the incidence and outcome of pneumococcal meningitis in adults over the last two decades. Despite recent advances pneumococcal meningitis remains associated with a residual high rate of mortality and morbidity.

Sex Differences in Long-term Outcomes After Group B Streptococcal Infections During Infancy in Denmark and the Netherlands: National Cohort Studies of Neurodevelopmental Impairments and Mortality.

BACKGROUND: Male infants have a higher incidence of invasive group B Streptococcus disease (iGBS) compared with female infants; however, data on sex differences in mortality and long-term outcomes after iGBS are lacking. We assessed whether a child's sex influences the effects of iGBS on mortality and risk of neurodevelopmental impairments (NDIs). METHODS: We used Danish and Dutch registry data to conduct a nationwide cohort study of infants with a history of iGBS. A comparison cohort, children without a history of iGBS, was randomly selected and matched on relevant factors. Effect modification by sex was assessed on additive and multiplicative scales. RESULTS: Our analyses included data from children with a history of iGBS in Denmark (period 1997 -2017; n = 1432) and the Netherlands (2000 -2017; n = 697) and from 21 172 children without iGBS. There was no clear evidence of between-sex heterogeneity in iGBS-associated mortality. Boys had a higher risk of NDI, with evidence for effect modification on additive scale at the age of 5 years for any NDI (relative excess risk due to interaction = 1.28; 95% confidence interval [CI], -0.53 to 3.09 in Denmark and 1.14; 95% CI, -5.13 to 7.41 in the Netherlands). A similar pattern was observed for moderate/severe NDI at age 5 years in Denmark and age 10 years in the Netherlands. CONCLUSION: Boys are at higher risk of NDI ; our results suggest this is disproportionally increased in those who develop iGBS. Future studies should investigate mechanisms of this effect modification by sex.

Prematurity Modifies the Risk of Long-term Neurodevelopmental Impairments After Invasive Group B Streptococcus Infections During Infancy in Denmark and the Netherlands.

BACKGROUND: Preterm birth and neonatal infections are both associated with mortality and long-term neurodevelopmental impairments (NDIs). We examined whether the effect of invasive group B Streptococcus disease (iGBS) on mortality and long-term NDI differs for preterm and term infants, and whether co-occurrence of iGBS and prematurity leads to worse outcome. METHODS: Nationwide cohort studies of children with a history of iGBS were conducted using Danish and Dutch medical databases. Comparison cohorts of children without iGBS were matched on birth year/month, sex, and gestational age. Effects of iGBS on all-cause mortality and NDI were analyzed using Cox proportional hazards and logistic regression. Effect modification by prematurity was evaluated on additive and multiplicative scales. RESULTS: We identified 487 preterm and 1642 term children with a history of iGBS and 21 172 matched comparators. Dutch preterm children exposed to iGBS had the highest mortality rate by 3 months of age (671/1000 [95% CI, 412-929/1000] person-years). Approximately 30% of this mortality rate could be due to the common effect of iGBS and prematurity. Preterm children with iGBS had the highest NDI risk (8.8% in Denmark, 9.0% in the Netherlands). Of this NDI risk 36% (Denmark) and 60% (the Netherlands) might be due to the combined effect of iGBS and prematurity. CONCLUSIONS: Prematurity is associated with iGBS development. Our study shows that it also negatively impacts outcomes of children who survive iGBS. Preterm infants would benefit from additional approaches to prevent maternal GBS colonization, as this decreases risk of both preterm birth and iGBS.

Changing Epidemiology of Bacterial Meningitis Since Introduction of Conjugate Vaccines: 3 Decades of National Meningitis Surveillance in The Netherlands.

BACKGROUND: The epidemiology of acute bacterial meningitis has changed substantially since the introduction of conjugate vaccines. METHODS: We analyzed nationwide surveillance data of all cerebrospinal fluid isolates received by the Netherlands Reference Laboratory for Bacterial Meningitis in the Netherlands. We assessed the impact of conjugate vaccines on incidence (defined as episodes per 100 000 population per year) and for different age groups using incidence rate ratios (IRRs), comparing incidence before and after conjugate vaccine introduction. RESULTS: We analyzed 17 393 episodes, of which 5960 episodes (34%) occurred in preschool children (aged 3 months to 4 years). Overall, bacterial meningitis incidence decreased from 6.37 to 1.58 between 1989-1993 and 2014-2019 (IRR, 0.25 [95% confidence interval {CI}, .23-.26]; P < .001). This decrease was most pronounced in preschool and school-aged children (5-15 years); IRR, 0.10 [95% CI, .09-.12] and 0.08 [95% CI, .06-.10]; both P < .001. The incidence was highest in young infants (<90 days) due to a high incidence of group B Streptococcus and Escherichia coli meningitis (42.48 and 19.49, respectively). Conjugate vaccines effectively reduced the incidence of Haemophilus influenzae type b, Neisseria meningitidis serogroup C, and 10 pneumococcal serotypes (IRRs, .02-.04; P < .001). At the end of the observed period, Streptococcus pneumoniae caused the majority of meningitis cases (829/1616 [51%]), mostly in older adults (aged 45-64 years) and elderly adults (aged ≥65 years; incidence of 1.06 and 1.54, respectively). CONCLUSIONS: Conjugate vaccines reduced the burden of bacterial meningitis, especially in children. The efforts for new measures to prevent bacterial meningitis should be focused on neonates and elderly, as the residual rate of disease is still high in these age groups.

Stratification of Culture-Proven Early-Onset Sepsis Cases by the Neonatal Early-Onset Sepsis Calculator: An Individual Patient Data Meta-Analysis.

OBJECTIVES: To provide a comprehensive assessment of case stratification by the Neonatal Early-Onset Sepsis (EOS) Calculator, a novel tool for reducing unnecessary antibiotic treatment. STUDY DESIGN: A systematic review with individual patient data meta-analysis was conducted, extending PROSPERO record CRD42018116188. Cochrane, PubMed/MEDLINE, EMBASE, Web of Science, Google Scholar, and major conference proceedings were searched from 2011 through May 1, 2020. Original data studies including culture-proven EOS case(s) with EOS Calculator application, independent from EOS Calculator development, and including representative birth cohorts were included. Relevant (individual patient) data were extracted from full-text and data queries. The main outcomes were the proportions of EOS cases assigned to risk categories by the EOS Calculator at initial assessment and within 12 hours. Evidence quality was assessed using Newcastle-Ottawa scale, Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies, and GRADE tools. RESULTS: Among 543 unique search results, 18 were included, totaling more than 459 000 newborns. Among 234 EOS cases, EOS Calculator application resulted in initial assignments to (strong consideration of) empiric antibiotic administration for 95 (40.6%; 95% CI, 34.2%-47.2%), more frequent vital signs for 36 (15.4%; 95% CI, 11.0%-20.7%), and routine care for 103 (44.0%; 95% CI, 37.6%-50.6%). By 12 hours of age, these proportions changed to 143 (61.1%; 95% CI, 54.5%-67.4%), 26 (11.1%; 95% CI, 7.4%-15.9%), and 65 (27.8%; 95% CI, 22.1%-34.0%) of 234 EOS cases, respectively. CONCLUSIONS: EOS Calculator application assigns frequent vital signs or routine care to a substantial proportion of EOS cases. Clinical vigilance remains essential for all newborns.

Community-acquired bacterial meningitis.

PURPOSE OF REVIEW: Bacterial meningitis is a medical emergency and is associated with a high disease burden. We reviewed recent progress in the management of patients with community-acquired bacterial meningitis. RECENT FINDINGS: The worldwide burden of disease of bacterial meningitis remains high, despite the decreasing incidence following introduction of routine vaccination campaigns. Delay in diagnosis and treatment remain major concerns in the management of acute bacterial meningitis. European Society of Clinical Microbiology and Infectious Diseases guidelines strive for a door-to-antibiotic-time less than 1 h. Polymerase chain reaction (PCR) has emerged as an important diagnostic tool to identify the causative organism. Point-of-care tests using fast multiplex PCR have been developed, but additional value has not been proven. Although anecdotal observations advocate pressure-based management, a randomized controlled trial will need to be performed first to determine efficacy and safety of such an aggressive treatment approach. Adjunctive dexamethasone remains the only adjunctive therapy with proven efficacy. SUMMARY: The incidence of bacterial meningitis has been decreasing after the implementation of effective vaccines. Treatment should be administered as soon as possible and time to treatment should not exceed 1 h.

A decade of herd protection after introduction of meningococcal serogroup C conjugate vaccination.

BACKGROUND: Vaccination with meningococcal serogroup C (MenC) conjugate (MCC) polysaccharide vaccines led to a substantial decline in MenC disease in the vaccinated and the unvaccinated population. The decline in the unvaccinated population can be explained by herd protection by reduced colonization of meningococci expressing the MenC capsule. The duration of such herd protection is unknown. METHODS: In a nationwide study from the Netherlands, we compared MenC invasive disease between 1998 and the introduction of MCC vaccination (2002) with that from 2002 to 2012, in age groups eligible and not eligible for vaccination. The proportions of isolates from clonal complexes with high serogroup C capsule expression rate during carriage (sequence type [ST] 11 and ST-8 complex) was compared between the pre- and postvaccination periods. RESULTS: A total of 814 patients with invasive MenC disease were included for analysis. There was a 99% decline in MenC disease in patients eligible for vaccination and a 93% decline in those not eligible. Thirty-six percent of the overall MenC reduction between the first and last 4 years of the observation period occurred in the unvaccinated population. Clonal complex was determined in 350 (43%) isolates. The proportion of cases caused by clonal complex ST-11 and ST-8 serogroup C meningococci decreased from 251 of 268 (94%) before, to 46 of 57 (81%) after MCC vaccine introduction (P = .004). CONCLUSIONS: Our findings provide further evidence that herd protection results from reduced carriage of virulent meningococci. Herd protection was responsible for >36% of MCC vaccine impact and lasted for ≥10 years.

Why pediatricians fail to diagnose hypertension: a multicenter survey.

OBJECTIVE: To elucidate why pediatricians fail to diagnose childhood hypertension, with special emphasis on the use of blood pressure (BP) reference data. We hypothesized that pediatricians frequently omit BP measurements and do not routinely relate BP measurements to reference data. STUDY DESIGN: We conducted a multicenter survey on BP measurement among 197 participants. Respondents were asked to estimate BP percentiles and classify BP readings in 12 example cases. Questionnaires were completed onsite in the presence of the researchers, without access to BP reference data. RESULTS: We found that 71% of physicians measure BP during ambulatory visits only if the child has risk factors for hypertension. After measuring BP, 65% compare the reading with reference data only if they suspect that it is elevated. Their ability to rate a reading at its true value is limited, however; 47% of the physicians classified 1 or more of the prehypertensive or hypertensive cases as normal. CONCLUSIONS: Most pediatricians do not screen for hypertension, contrary to recommendations. After obtaining a BP measurement, the majority do not compare the reading with reference standards; however, without the use of reference data, they commonly underestimate the BP percentile and potentially miss cases of childhood hypertension.

Long-term impact of serious neonatal bacterial infections on neurodevelopment.

BACKGROUND: Neonatal bacterial infections have long been recognized as an important cause of acute morbidity and mortality, but long-term neurodevelopmental consequences have not been comprehensively described and discussed. OBJECTIVES: We aimed to summarize evidence on the pathogenesis, diagnosis, and epidemiology of long-term sequelae after neonatal bacterial sepsis and meningitis. We also discuss approaches for future studies to quantify the public health impact of neonatal infection-associated neurodevelopmental impairment. SOURCES: We identified studies, both research articles and reviews, which provide mechanistic information on the long-term disease, as well as epidemiological studies that describe the frequency of neurodevelopmental impairment in children with and, for comparison, without a history of neonatal bacterial infection. Tools currently used in clinical practice and research settings to assess neurodevelopmental impairment were also reviewed. CONTENT: We first enumerate potential direct and indirect mechanisms that can lead to brain injury following neonatal infections. We then discuss summary data, either frequencies or measures of association, from epidemiological studies. Risk factors that predict long-term outcomes are also described. Finally, we describe clinical approaches for identifying children with neurodevelopmental impairment and provide an overview of common diagnostic tools. IMPLICATIONS: The limited number of studies that describe the long-term consequences of neonatal infections, often undertaken in high-income settings and using variable designs and diagnostic tools, are not sufficient to inform clinical practice and policy prioritization. Multi-country studies with follow-up into adolescence, standardized diagnostic approaches, and local comparator groups are needed, especially in low and middle-income countries where the incidence of neonatal sepsis is high.

Cerebrospinal fluid inflammatory markers to differentiate between neonatal bacterial meningitis and sepsis: A prospective study of diagnostic accuracy.

OBJECTIVES: We evaluated the diagnostic accuracy of cerebrospinal fluid (CSF) inflammatory markers for diagnosing bacterial meningitis in neonates with sepsis and/or meningitis. METHODS: Cases were identified from a prospective multicenter study including patients aged 0-3 months with Group B Streptococcal (GBS) or Escherichia coli culture positive sepsis/meningitis. CSF CXCL10, MDC, IL-6, IL-8, IL-10, TNF- α, MIF, IL-1RA, CXCL13, IL-1ß, CRP and procalcitonin concentrations were measured with Luminex technology. RESULTS: In 61/373 patients (17%) residual CSF from the lumbar puncture was available, of whom 16 (26%) had definitive meningitis, 15 (25%) probable meningitis and 30 (49%) had sepsis. All biomarkers were detectable in CSF and showed significantly higher concentrations in definitive meningitis versus sepsis patients and six biomarkers in probable meningitis versus sepsis patients. Discrimination between definitive meningitis and sepsis was excellent for IL-1RA (area under the receiver operating characteristic curve [AUC] 0.93), TNF-α (AUC 0.92), CXCL10 (AUC 0.90), IL-1ß (AUC 0.92), IL-6 (AUC 0.94), IL-10 (AUC 0.93) and a combination of IL-1RA, TNF-α, CXCL-10 and CSF leukocyte count (AUC 0.95). CSF leukocyte count remained the predictor with the highest diagnostic accuracy (AUC 0.96). CONCLUSION: CSF inflammatory markers can be used to differentiate between neonatal sepsis and meningitis.

Listeria monocytogenes sequence type 6 and increased rate of unfavorable outcome in meningitis: epidemiologic cohort study.

BACKGROUND: We analyzed clinical characteristics, treatment, genetic diversity, and outcome of 92 adults with Listeria monocytogenes meningitis included in 2 prospective nationwide cohort studies. METHODS: Episodes of community-acquired listerial meningitis confirmed by cerebrospinal fluid culture were included from 1998 to 2002 and 2006 to 2012. We compared patients and pathogen characteristics between cohorts and identified predictors for an unfavorable outcome according to the Glasgow Outcome Scale. RESULTS: Thirty episodes were included from 1998 to 2002 and 62 from 2006 to 2012; clinical and laboratory characteristics on admission were similar between cohorts. However, the rate of unfavorable outcome increased from 27% in the 1998-2002 cohort to 61% in the 2006-2012 cohort (P = .002). Differences between cohorts were increased use of adjunctive dexamethasone therapy (0% in 1998-2002 vs 53% in 2006-2012; P < .001) and emergence of infection by L. monocytogenes genotype sequence type 6 (ST6; 4% in 1998-2002 vs 29% in 2006-2012; P = .009). Multivariate regression analysis identified infection with L. monocytogenes ST6 as the sole predictor of unfavorable outcome (odds ratio, 3.77; 95% confidence interval, 1.07-13.33). Patients infected with genotypes other than ST6 also had an increased rate of unfavorable outcome over time (P = .03). CONCLUSIONS: The rate of unfavorable outcome among adults with listerial meningitis has increased over a 14-year period, from 27% to 61%. The emerging L. monocytogenes genotype ST6 was identified as the main factor leading to poorer prognosis. Adjunctive dexamethasone may be discontinued if L. monocytogenes is identified, as there is no proven benefit in Listeria meningitis.

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.

Meeting report: Towards better risk stratification, prevention and therapy of invasive GBS disease, ESPID research meeting May 2022.

The European Society of Pediatric Infectious Diseases (ESPID) hosted the third Group B Streptococcus (GBS) Research Session in Athens on 11th May 2022, providing researchers and clinicians from around the world an opportunity to share and discuss recent advances in GBS pathophysiology, molecular and genetic epidemiology and how these new insights can help in improving prevention and control of early- and late-onset GBS disease. The meeting provided a state-of-the-art overview of the existing GBS prevention strategies and their limitations, and an opportunity to share the latest research findings. The first presentation provided an overview of current GBS prevention and treatment strategies. In the second presentation, the genomic and antimicrobial resistance profiles of invasive and colonizing GBS strains were presented. The third presentation explained the association of intrapartum antibiotic prophylaxis (IAP) with the development of late-onset disease (LOD) and the interplay of host innate immunity and GBS. The fourth presentation evaluated the role of genomics in understanding horizontal GBS transmission. The fifth presentation focused on the zoonotic links for certain GBS lineages and the last presentation described the protective role of breastmilk. Talks were followed with interactive discussions and concluded with recommendations on what is needed to further GBS clinical research; these included: (i) the development of better risk stratification methods by combining GBS virulence factors, serological biomarkers and clinical risk factors; (ii) further studies on the interplay of perinatal antimicrobials, disturbances in the development of host immunity and late-onset GBS disease; (iii) routine submission of GBS isolates to reference laboratories to help in detecting potential clusters by using genomic sequencing; (iv) collaboration in animal and human GBS studies to detect and prevent the emergence of new pathogenic sequence types; and (v) harnessing the plethora of immune factors in the breastmilk to develop adjunct therapies.

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.

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.