Simulated effect of pneumococcal vaccination in the Netherlands on existing rules constructed in a non-vaccinated cohort predicting sequelae after bacterial meningitis

BACKGROUND: Previously two prediction rules identifying children at risk of hearing loss and academic or behavioral limitations after bacterial meningitis were developed. Streptococcus pneumoniae as causative pathogen was an important risk factor in both. Since 2006 Dutch children receive seven-valent conjugate vaccination against S. pneumoniae. The presumed effect of vaccination was simulated by excluding all children infected by S. pneumoniae with the serotypes included in the vaccine, from both previous collected cohorts (between 1990-1995). METHODS: Children infected by one of the vaccine serotypes were excluded from both original cohorts (hearing loss: 70 of 628 children; academic or behavioral limitations: 26 of 182 children). All identified risk factors were included in multivariate logistic regression models. The discriminative ability of both new models was calculated. RESULTS: The same risk factors as in the original models were significant. The discriminative ability of the original hearing loss model was 0.84 and of the new model 0.87. In the academic or behavioral limitations model it was 0.83 and 0.84 respectively. CONCLUSION: It can be assumed that the prediction rules will also be applicable on a vaccinated population. However, vaccination does not provide 100% coverage and evidence is available that serotype replacement will occur. The impact of vaccination on serotype replacement needs to be investigated, and the prediction rules must be validated externally

Predicting sequelae and death after bacterial meningitis in childhood: A systematic review of prognostic studies

Background: Bacterial meningitis (BM) is a severe infection responsible for high mortality and disabling sequelae. Early identification of patients at high risk of these outcomes is necessary to prevent their occurrence by adequate treatment as much as possible. For this reason, several prognostic models have been developed. The objective of this study is to summarize the evidence regarding prognostic factors predicting death or sequelae due to BM in children 0-18 years of age. Methods: A search in MEDLINE and EMBASE was conducted to identify prognostic studies on risk factors for mortality and sequelae after BM in children. Selection of abstracts, full-text articles and assessment of methodological quality using the QUIPS checklist was performed by two reviewers independently. Data on prognostic factors per outcome were summarized. Results: Of the 31 studies identified, 15 were of moderate to high quality. Due to substantial heterogeneity in study characteristics and evaluated prognostic factors, no quantitative analysis was performed. Prognostic factors found to be statistically significant in more than one study of moderate or high quality are: complaints > 48 hours before admission, coma/impaired consciousness, (prolonged duration of) seizures, (prolonged) fever, shock, peripheral circulatory failure, respiratory distress, absence of petechiae, causative pathogen Streptococcus pneumoniae, young age, male gender, several cerebrospinal fluid (CSF) parameters and white blood cell (WBC) count. Conclusions: Although several important prognostic factors for the prediction of mortality or sequelae after BM were identified, the inability to perform a pooled analysis makes the exact (independent) predictive value of these factors uncertain. This emphasizes the need for additional well-conducted prognostic studie

Prediction of academic and behavioural limitations in school-age survivors of bacterial meningitis.

Aim: To develop a prediction rule to identify postmeningitic children at high risk of academic and behavioural limitations. Methods: 182 children (mean age 10 y; range 5-14) were selected from a cohort of 674 school-age survivors of bacterial meningitis. These children had neither meningitis with "complex onset", nor prior cognitive or behavioural problems, nor severe disease sequelae. On average, 7 y after the meningitis, they were evaluated using an "Academic Achievement Test", and their parents filled in the "Child Behaviour Checklist". By reviewing the medical records, potential risk factors for academic and/or behavioural limitations were collected. Independent predictors were identified using multivariate logistic regression analysis, leading to the formulation of a prediction rule. Results: The cumulative incidence of academic and/or behavioural limitations among children who survived bacterial meningitis without severe disease sequelae was 32%. The prediction rule was based on nine independent risk factors: gender, birthweight, educational level of the father, S. pneumoniae, cerebrospinal fluid leukocyte count, delay between admission and start of antibiotics, dexamethasone use, seizures treated with anticonvulsive therapy, and prolonged fever. When 10 was taken as a cut-off point for the risk score computed using this rule, 76% of the children with limitations could be identified, while 38% of the children in the cohort were selected as at risk for these limitations. Conclusion: With a prediction rule based on nine risk factors, postmeningitic children at high risk of developing academic and/or behavioural limitations could be identified. Additional research is required to further validate this prediction rule. In the future, a careful follow-up of high risk children may enhance early detection and treatment of these limitations