Individual responsiveness of macrophage migration inhibitory factor predicts long-term cognitive impairment after bacterial meningitis.

BACKGROUND: Patients with pneumococcal meningitis are at risk for death and neurological sequelae including cognitive impairment. Functional genetic polymorphisms of macrophage migration inhibitory factor (MIF) alleles have shown to predict mortality of pneumococcal meningitis. METHODS: We investigated whether MIF concentrations during the acute phase of disease were predictive for death in a nationwide prospective cohort study. Subsequently, we studied whether individual ex vivo MIF response years after meningitis was associated with the development of cognitive impairment. RESULTS: We found that in the acute illness of pneumococcal meningitis, higher plasma MIF concentrations were predictive for mortality (p = 0.009). Cognitive impairment, examined 1-5 years after meningitis, was present in 11 of 79 patients after pneumococcal meningitis (14%), as compared to 1 of 63 (2%) in controls, and was consistently associated with individual variability in MIF production by peripheral blood mononuclear cells after ex vivo stimulation with various infectious stimuli. CONCLUSIONS: Our study confirms the role of MIF in poor disease outcome of pneumococcal meningitis. Inter-individual differences in MIF production were associated with long-term cognitive impairment years after pneumococcal meningitis. The present study provides evidence that MIF mediates long-term cognitive impairment in bacterial meningitis survivors and suggests a potential role for MIF as a target of immune-modulating adjunctive therapy.

MeningiSSS: A New Predictive Score to Support Decision on Invasive Procedures to Monitor or Manage the Intracerebral Pressure in Children with Bacterial Meningitis.

BACKGROUND: Knowing the individual child's risk is highly useful when deciding on treatment strategies, especially when deciding on invasive procedures. In this study, we aimed to develop a new predictive score for children with bacterial meningitis and compare this with existing predictive scores and individual risk factors. METHODS: We developed the Meningitis Swedish Survival Score (MeningiSSS) based on a previous systematic review of risk factors. From this, we selected risk factors identified in moderate-to-high-quality studies that could be assessed at admission to the hospital. Using data acquired from medical records of 101 children with bacterial meningitis, we tested the overall capabilities of the MeningiSSS compared with four existing predictive scores using a receiver operating characteristic curve (ROC) analysis to assert the area under the curve (AUC). Finally, we tested all predictive scores at their cut-off levels using a Chi-square test. As outcome, we used a small number of predefined outcomes; in-hospital mortality, 30-day mortality, occurrence of neurological disabilities at discharge defined as Pediatric Cerebral Performance Category Scale category two to five, any type of complications occurring during the hospital stay, use of intensive care, and use of invasive procedures to monitor or manage the intracerebral pressure. RESULTS: For identifying children later undergoing invasive procedures to monitor or manage the intracerebral pressure, the MeningiSSS excelled in the ROC-analysis (AUC = 0.90) and also was the only predictive score able to identify all cases at its cut-off level (25 vs 0%, p < 0.01). For intensive care, the MeningiSSS (AUC = 0.79) and the Simple Luanda Scale (AUC = 0.75) had the best results in the ROC-analysis, whereas others performed less well (AUC ≤ 0.65). Finally, while none of the scores' results were significantly associated with complications, an elevated score on the MeningiSSS (AUC = 0.70), Niklasson Scale (AUC = 0.72), and the Herson-Todd Scale (AUC = 0.79) was all associated with death. CONCLUSIONS: The MeningiSSS outperformed existing predictive scores at identifying children later having to undergo invasive procedures to monitor or manage the intracerebral pressure in children with bacterial meningitis. Our results need further external validation before use in clinical practice. Thus, the MeningiSSS could potentially be helpful when making difficult decisions concerning intracerebral pressure management.

Meningococcal carriage by age in the African meningitis belt: a systematic review and meta-analysis.

Meningococcal carriage dynamics drive patterns of invasive disease. The distribution of carriage by age has been well described in Europe, but not in the African meningitis belt, a region characterised by frequent epidemics of meningitis. We aimed to estimate the age-specific prevalence of meningococcal carriage by season in the African meningitis belt. We searched PubMed, Web of Science, the Cochrane Library and grey literature for papers reporting carriage of Neisseria meningitidis in defined age groups in the African meningitis belt. We used a mixed-effects logistic regression to model meningococcal carriage prevalence as a function of age, adjusting for season, location and year. Carriage prevalence increased from low prevalence in infants (0.595% in the rainy season, 95% CI 0.482-0.852%) to a broad peak at age 10 (1.94%, 95% CI 1.87-2.47%), then decreased in adolescence. The odds of carriage were significantly increased during the dry season (OR 1.5 95% CI 1.4-1.7) and during outbreaks (OR 6.7 95% CI 1.6-29). Meningococcal carriage in the African meningitis belt peaks at a younger age compared to Europe. This is consistent with contact studies in Africa, which show that children 10-14 years have the highest frequency of contacts. Targeting older children in Africa for conjugate vaccination may be effective in reducing meningococcal transmission.

Differential influences of complement on neutrophil responses to Neisseria meningitidis infection.

The complement system is the primary innate immune determinant protecting against invasive diseases caused by the Gram-negative bacterium Neisseria meningitidis (Nme, meningococcus), as evidenced by the extreme susceptibility of individuals with complement deficiencies. In contrast, the role of phagocytes such as neutrophils is much less well understood, although they are recruited in great numbers to the cerebrospinal fluid during meningococcal meningitis. Here, we consider the interaction of Nme with primary human neutrophils using either purified cells or a whole blood model of infection. We found that neutrophils are capable of non-opsonic uptake and killing of different Nme strains. However, in the presence of immune serum featuring active complement, Nme association is strongly increased, whereas this is not the case in heat-inactivated immune serum. Blockade of complement at the level of C3 using the inhibitor compstatin Cp20 reduces the uptake dramatically. In addition, purified neutrophils did not mount an oxidative burst towards Nme unless complement was added and, vice versa, the oxidative burst was strongly reduced in whole blood upon complement inhibition. In contrast, there was no significant impact of complement on neutrophil degranulation or IL-8 secretion. Taken together, neutrophils require complement activation in order to mount a full response towards Nme.

Diagnostic challenges with acellular bacterial meningitis.

An immunocompetent adult presenting with acellular pneumococcal meningitis is a rare occurrence and may pose a diagnostic challenge.

Case-Fatality Rates and Sequelae Resulting from Neisseria meningitidis Serogroup C Epidemic, Niger, 2015.

We describe clinical symptoms, case-fatality rates, and prevalence of sequelae during an outbreak of Neisseria meningitidis serogroup C infection in a rural district of Niger. During home visits, we established that household contacts of reported case-patients were at higher risk for developing meningitis than the general population.

Clinical findings and management of patients with meningitis with an emphasis on Haemophilus influenzae meningitis in rural Tanzania.

INTRODUCTION: The spectrum of meningitis pathogens differs depending on the age of patients and the geographic region, amongst other. Although meningitis vaccination programs have led to the reduction of incidence rates, an imbalance between low- and high-income countries still exists. METHODS: In a hospital-based study in rural northern Tanzania, we consecutively recruited patients with confirmed meningitis and described their clinical and laboratory characteristics. RESULTS: A total of 136 patients with meningitis were included. Fever (85%), meningism (63%) and impairment of consciousness (33%) were the most frequent clinical symptoms/signs. Nearly 10% of all patients tested were positive for malaria. The majority of the patients with bacterial meningitis (39%), especially those under 5years of age, were confirmed to be infected with Haemophilus influenzae (26%), Streptococcus pneumoniae (19%) and Neisseria meningitidis (15%). Haemophilus influenzae represented the dominant causative organism in children under 2years of age. CONCLUSION: Our study emphasizes the importance of recognizing warning symptoms like fever, meningism and impairment of consciousness, implementing laboratory tests to determine responsible pathogens and evaluating differential diagnoses in patients with meningitis in sub-Saharan Africa. It also shows that Haemophilus influenza meningitis is still an important cause for meningitis in the young, most probabaly due to lack of appropriate vaccination coverage.

Outbreak of serotype W135 Neisseria meningitidis in central river region of the Gambia between February and June 2012: a hospital-based review of paediatric cases.

BACKGROUND: Meningitis still accounts for many deaths in children especially during epidemics in countries within the African meningitis belt. Between February and May 2012, the Gambia witnessed an outbreak of meningitis in two of its six regions. This study presents a clinical perspective of this outbreak in central river region of the Gambia. It evaluated the outbreak pattern, clinical features, and mortality among suspected cases that presented to the hospital during the outbreak. METHODOLOGY: This is a prospective observational study of suspected cases of meningitis that presented to the pediatric ward of the Bansang Hospital during the outbreak period. Confirmed cases of meningitis were consecutively enrolled, and those with negative blood cultures presenting during the same period were employed as controls. RESULT: Two hundred and four suspected cases of meningitis presented to the pediatric ward during the outbreak. Ninety were confirmed as meningitis cases. The W135 strain of Neisseria meningitidis was responsible for 89 (98.9%) of meningitis cases seen with an incidence rate of 74.9/100,000 in children (0-14 years) and in-hospital case fatality rate of 7.9%. Highest attack rate was among the 12-49 months age group. Clinical features such as meningeal signs (neck stiffness), conjunctivitis, and joint swelling were seen more in cases than controls. Contact history with relatives, who had fever in previous 2 weeks prior to illness was significantly seen more in cases. Adjusted regression analysis showed 7.5 more likelihood of infection with positive contact history (odds ratio [OR]: 7.2 confidence interval [CI]: [3.39-15.73]). There was no significant difference in death outcome between cases and controls (OR: 0.78 CI: [0.29-2.13]). The double peak wave-like pattern of the epidemic curve noted during this outbreak suggests a disseminated outbreak originating from an index case with propagated spread. CONCLUSION: There is need for more effective surveillance and incorporation of vaccine against meningitis into the expanded program on immunization schedule of the Gambia and other countries within the meningitic epidemic belt.

Educational achievement and economic self-sufficiency in adults after childhood bacterial meningitis.

IMPORTANCE: To our knowledge, no previous study has examined functioning in adult life among persons who had bacterial meningitis in childhood. OBJECTIVE: To study educational achievement and economic self-sufficiency in adults diagnosed as having bacterial meningitis in childhood. DESIGN, SETTING, AND PARTICIPANTS: Nationwide population-based cohort study using national registries of Danish-born children diagnosed as having meningococcal, pneumococcal, or Haemophilus influenzae meningitis in the period 1977-2007 (n=2784 patients). Comparison cohorts from the same population individually matched on age and sex were identified, as were siblings of all study participants. End of study period was 2010. MAIN OUTCOMES AND MEASURES: Cumulative incidences of completed vocational education, high school education, higher education, time to first full year of economic self-sufficiency, and receipt of disability pension and differences in these outcomes at age 35 years among meningitis patients, comparison cohorts, and siblings. RESULTS: By age 35 years, among persons who had a history of childhood meningococcal (n=1338), pneumococcal (n=455), and H. influenzae (n=991) meningitis, an estimated 11.0% (41.5% vs 52.5%; 95% CI, 7.3%-14.7%), 10.2% (42.6% vs 52.8%; 95% CI, 3.8%-16.6%), and 5.5% (47.7% vs 53.2%; 95% CI, 1.9%-9.1%) fewer persons, respectively, had completed high school and 7.9% (29.3% vs 37.2%; 95% CI, 1.6%-14.2%), 8.9% (28.1% vs 37.0%; 95% CI, 0.6%-17.2%), and 6.5% (33.5% vs 40.0%; 95% CI, 1.4%-11.6%) fewer had attained a higher education compared with individuals from the comparison cohort. Siblings of meningococcal meningitis patients also had lower educational achievements, while educational achievements of siblings of pneumococcal and H. influenzae meningitis patients did not differ substantially from those in the general population. At end of follow-up, 3.8% (90.3% vs 94.1%; 95% CI, 1.1%-6.5%), 10.6% (84.0% vs 94.6%; 95% CI, 5.1%-16.1%), and 4.3% (90.6% vs 94.9%; 95% CI, 2.0%-6.6%) fewer meningococcal, pneumococcal, and H. influenzae meningitis patients were economically self-sufficient and 1.5% (3.7% vs 2.3%; 95% CI, -0.2% to 3.2%), 8.7% (10.0% vs 1.3%; 95% CI, 5.0%-12.4%), and 3.7% (6.2% vs 2.5%; 95% CI, 1.6%-5.8%) more received disability pension compared with individuals from the comparison cohort. CONCLUSIONS AND RELEVANCE: In a Danish population, bacterial meningitis in childhood was associated with lower educational achievement and economic self-sufficiency in adult life. This association may apply particularly to pneumococcal and H. influenzae meningitis, whereas for meningococcal meningitis the lower educational achievement may be family-related.

Counting the cost of meningococcal disease : scenarios of severe meningitis and septicemia.

BACKGROUND: Meningococcal disease can result in severe disabling sequelae, but there is no published information about the lifelong rehabilitation costs of patients with severe outcome in the UK. As cost-effectiveness studies play a crucial role in determining whether immunization programmes will be implemented, it is important to identify these costs. OBJECTIVE: The aim of the study was to estimate lifelong rehabilitation costs associated with severe cases of meningococcal disease and to present these costs in a format appropriate for use in a cost-effectiveness analysis. METHODS: Two severe scenarios of meningococcal disease with major sequelae were developed; one that presented acutely as meningitis and the other as septicemia. Scenarios were based on systematic reviews of the literature describing the sequelae of meningococcal disease, dialogue with Meningitis Research Foundation members who have experience of the disease, and discussions with pediatricians who have been responsible for managing children with this disease over many years. The two scenarios were devised to represent cases typical of the severe end of the spectrum. To obtain a comprehensive list of the health, educational and other resources used by survivors during and since their acute illness, families of individuals with sequelae similar to those in each of our scenarios were interviewed. Relevant academics and professionals in health, social care and education were consulted in order to ensure that our scenarios accurately represented the treatment and support that individuals with such sequelae might realistically receive from the National Health Service (NHS), the local authority and Personal Social Services (PSS). The majority of costs were derived from English Department of Health reference costs and unit costs of health and social care reflecting values for the financial year 2008-2009 indexed to 2010-2011. Costs were based on a life expectancy of 70 years in each scenario and are presented at a discount rate of 3.5 % for the first 30 years and 3 % thereafter, as recommended by the UK treasury (non-discounted costs are also presented for comparison). Costs are presented from both an NHS/PSS perspective and a government perspective. RESULTS: This study has revealed that severe cases of disease that result in long-term sequelae can result in costs to the NHS/PSS of around £160,000-£200,000 in the first year alone. Over a lifetime of 70 years, discounted costs from an NHS/PSS perspective ranged from approximately £590,000 to £1,090,000 (£1,250,000-£3,320,000 undiscounted) and discounted costs from a government perspective ranged from £1,360,000 to £1,720,000 (£3,030,000-£4,470,000 undiscounted). CONCLUSION: This study fills a gap in the UK literature and produces estimates that can be used in cost-effectiveness analysis to better represent the cost of illness at the severe end of the spectrum. Costs from a government perspective highlight the wider impacts of this disease, which is important for clinical decision makers, and budgetary and service planners to be aware of when making decisions about the benefits of implementing public health interventions such as immunization programmes.

Coadministration of the cyanobacterial lipopolysaccharide antagonist CyP with antibiotic inhibits cytokine production by an in vitro meningitis model infected with Neisseria meningitidis.

OBJECTIVES: In this study, the objective was to determine the anti-inflammatory properties of CyP, a cyanobacterial lipopolysaccharide (LPS) antagonist, used in combination with antibiotic chemotherapy during infection of an in vitro meningitis model infected with Neisseria meningitidis (meningococcus). METHODS: Monocultures of human meningioma cells and meningioma-primary human macrophage co-cultures were infected with meningococci (10(2)-10(8) cfu/monolayer) or treated with isolated outer membranes or purified LPS (0.1-100 ng/monolayer) from N. meningitidis. CyP (1-20 µg/monolayer) was added at intervals from t = 0 to 4 h, with and without benzylpenicillin (1-20 µg/monolayer). The antagonistic effect of CyP and its adjunctive properties to benzylpenicillin administration was determined by measuring cytokine levels in culture supernatants after 24 h. RESULTS: CyP significantly inhibited (P < 0.05) the secretion of interleukin (IL)-6, IL-8, monocyte chemoattractant protein (MCP)-1 and RANTES ('regulated upon activation, normal T cell expressed and secreted') (overall reduction levels from 50% to >95%) by meningioma cell lines and meningioma-macrophage co-cultures challenged with either live meningococci or bacterial components. Inhibition was effective when CyP was added within 2 h of challenge (P < 0.05) and was still pronounced by 4 h. In the co-culture model, CyP alone partially inhibited IL-1ß secretion, but did not prevent tumour necrosis factor (TNF)-α secretion, whereas penicillin alone inhibited IL-1ß and TNF-α but conversely did not reduce MCP-1 and RANTES secretion. However, coadministration of CyP and penicillin in both models had an additive effect and restored the overall inhibitory profile. CONCLUSIONS: CyP inhibits cytokine production in an in vitro meningitis model and augments the anti-inflammatory response when combined with benzylpenicillin. Administration of an LPS antagonist with antibiotic merits consideration in the emergency treatment of patients presenting with meningococcal infection.

Advanced therapeutic methods for the treatment of meningococcal septic shock - case report.

BACKGROUND: Meningitis caused by Neisseria meningitidis is primarily a disease of children and young adults. If septic shock complicates the course of meningitis, it must be treated in the intensive care unit. CASE REPORT: An 18 year-old man with symptoms of meningococcal meningitis and clinical features of septic shock was admitted to the ICU. Tachycardia (heart rate 140 min⁻¹) required vasopressor to maintain blood pressure (noradrenalin 1 µg kg⁻¹ min⁻¹) on admission. Respiratory failure developed (respiratory rate of 40 min⁻¹, SaO2 79%, PaO2/FiO2 ratio = 55) and mechanical ventilatory support was used. The presence of Neisseria meningitidis was confirmed by a rapid latex agglutination test. Cefotaxime with vancomycin was administered on day one, and vancomycin was replaced by meropenem on day two. Additionally to the standard treatment of septic shock and multiorgan failure, haemoperfusion with LPS adsorber was performed to eliminate endotoxins from the bloodstream, and drotrecogin alfa was administered. Haemoperfusion was performed twice for sessions of two hours, and blood endotoxin activity decreased from 0.75 EAU to 0.4 EAU after 48 hours. The patient was admitted with signs of acute kidney injury and required continuous renal replacement therapy (Ca-Ca CVVHD, CVVHDF). CONCLUSIONS: Rapid pathogen identification, adequate antimicrobial therapy and endotoxin elimination from the bloodstream improved the haemodynamic and respiratory parameters of the patient. The application of routine plus non-standard methods of treatment of septic shock prevented the progression of the biological cascade in sepsis, and improved the patient's clinical condition.

Neisseria meningitidis serogroup B meningitis relapse after five days of cefotaxime treatment: what went wrong?

The authors describe a case of relapse of Neisseria meningitidis serogroup B meningitis in a 21-y-old male, 48 h after a 5-day treatment with cefotaxime 215 mg/kg per day. Brain magnetic resonance imaging (MRI) excluded the hypothesis of cerebral abscess or central venous septic thrombosis, and transthoracic echocardiography excluded bacterial endocarditis. Complement, properdin, and protein electrophoresis were normal. The plausible explanations for this relapse and the implications for other similar cases are discussed.

The implications of vaccines for prevention of bacterial meningitis.

PURPOSE OF REVIEW: Conjugate vaccines now exist that can protect against some types of bacterial meningitis (Haemophilus influenzae type b, Neisseria meningitidis group C and seven serotypes of Streptococcus pneumoniae). To broaden the protection against meningitis, new vaccines are needed. This article reviews new uses of the established vaccines and the new meningitis vaccines in development. RECENT FINDINGS: A conjugate group A meningococcal vaccine to prevent epidemics of meningitis in Africa is about to be used widely in the 'meningitis belt'. A 'quadrivalent' conjugate vaccine against meningococcal serogroups A C Y and W135 is in use in the United States. A 'tailor-made' group B meningococcal vaccine was successfully used to control an epidemic of meningococcal disease in New Zealand. Other group B meningococcal vaccines are in development. Despite routine vaccination against pneumococcus in the United States, this organism is still the commonest cause of meningitis. Pneumococcal vaccines need to include more serotypes to offer broader protection. SUMMARY: Great progress has been made in developing vaccines that prevent meningitis. The remaining challenges are to introduce vaccines with broad protection against meningococci and pneumococcus, develop an effective vaccine against group B meningococcus and to get these highly effective vaccines to those areas of the world that most need them.

Neuropeptide alpha-MSH exerts pro-inflammatory effects on Neisseria meningitidis infection in vitro.

OBJECTIVE AND DESIGN: alpha-Melanoycte stimulating hormone (alpha-MSH), a neuropeptide hormone with reported anti-microbial and immuno-modulatory properties in vitro, has previously been detected in the cerebrospinal fluid of children with bacterial meningitis. We investigated the therapeutic effects of alpha-MSH administration on Neisseria meningitidis infection of human meningeal cell cultures in vitro. MATERIALS AND METHODS: Meningeal cell lines (n = 2) were infected with meningococci (10(2)-10(8) cfu/monolayer), isolated bacterial outer membranes (OM; 1 microg/ml) or lipo-oligosaccharide (LOS; 1 microg/ml) with and without alpha-MSH (10(-5)-10 microM). Bacterial adherence was quantified at 6 h, and cytokine production and microbicidal activity of alpha-MSH for meningococci were assessed at 24 h. RESULTS: Compared with infection by meningococci alone, alpha-MSH (10 microM) up-regulated secretion of IL-6 and IL-8 (mean values increased from approximately 33 to 60 ng/ml), RANTES (mean values increased from approximately 26 to 105 ng/ml) and GM-CSF (mean values increased from approximately 0.3 to 1 ng/ml; P < 0.05). Upregulated secretion correlated with a neuropeptide-mediated rapid and >5-fold increase (P < 0.05) in bacterial adherence to cells and was dependent on OM components including LOS acting synergistically with alpha-MSH. Meningococci were resistant to the anti-microbial activity of alpha-MSH at all concentrations tested. CONCLUSIONS: Our study demonstrates that a potentially therapeutic neuropeptide exerts pro-inflammatory effects during meningococcal infection in vitro and its use in the treatment of meningitis is contra-indicated.

A novel mutation in a patient with a deficiency of the eighth component of complement associated with recurrent meningococcal meningitis.

INTRODUCTION: Complement component C8 is one of the five terminal complement components required for the formation of the membrane attack complex. Complete absence of C8 results in increased susceptibility to gram-negative bacteria such as Neisseria species. MATERIALS AND METHODS: Two functionally distinct C8 deficiency states have been described: C8 alpha-gamma deficiency has been predominantly reported amongst Afro-Caribbeans, Hispanics, and Japanese and C8beta mainly in Caucasians. RESULTS: We report a case of functional and immunochemical deficiency of the complement component C8, diagnosed in a Caucasian adult following three episodes of meningitis. Western blotting and hemolytic assay demonstrated absence of C8beta. In genetic studies, the common exon 9 C > T transition responsible for 85% of C8beta deficiencies was not found. Two mutations were identified: a novel duplication mutation, c.1047_1053 dupGGCTGTG in exon 7 that introduces a frame shift, resulting in the addition of seven novel amino acid residues and a premature stop codon, and a previously reported mutation, c.271C > T in exon 3. The parents each expressed one of these mutations, confirming compound heterozygosity. DISCUSSION: This is the first report of a duplication mutation in C8beta deficiency and extends the molecular heterogeneity of the disorder.