Key Question 1. What are the causative microorganisms of community-acquired bacterial meningitis in specific groups (neonates, children, adults and immunocompromised patients)?

Case fatality ratio and permanent sequelae of acute bacterial meningitis remain high in recent decades. A prospective longitudinal study of adult patients admitted with community acquired acute bacterial meningitis at a tertiary infectious diseases unit aimed to identify predictors of unfavourable outcome - death and sequelae. Anamnestic, clinical and laboratory data and clinical outcome were recorded. From 1997 to 2006, 279 adults (122F, 157M) with a median age of 51 y were admitted with acute bacterial meningitis. Predisposing condition and comorbidity were recorded in 42% and 38% of patients, respectively. Time between symptoms onset and antibiotic treatment ranged from 6 to 160 h. An aetiological agent was identified in 77% of patients: Streptococcus pneumoniae (29%) and Neisseria meningitidis (27%) were the most frequent. 55 patients (20%) died and 63 (23%) had neurological sequelae 6 months after discharge. In multivariate analysis, 7 independent predictors of unfavourable outcome were identified: internal comorbidity, time to treatment >48 h, coma, hypotension, high CSF protein, low glucose ratio, and non-meningococcal aetiology. The results suggest that acute bacterial meningitis remains associated with significant morbidity and mortality. Maintaining a high clinical suspicion and initiating appropriate diagnostic testing and therapeutic interventions promptly are essential for an optimal clinical outcome.

Invasive meningococcal disease continues to be a life-threatening condition and rapid diagnosis is important for the administration of appropriate treatment. This study focused on the use of PCR for the diagnosis of meningococcal aetiology and the dynamics of PCR-based diagnosis over time in various biological samples. Sixty cerebrospinal fluid (CSF) and 144 serum samples collected during the first week of hospitalisation from 37 patients with laboratory-confirmed invasive meningococcal disease were investigated. Overall, 91.9% of CSF samples and 45.9% of serum samples were PCR-positive, while culture of CSF and blood was positive for only 35% and 39% samples, respectively. Positive PCR results were obtained until day 7 with CSF and until day 5 with serum. It is therefore recommended that samples for molecular diagnosis should be collected early in the course of suspected invasive meningococcal disease.

Introduction Outcomes following bacterial meningitis are significantly improved by adjunctive treatment with corticosteroids. However, little is known about the levels and significance of intrathecal endogenous cortisol. The aim of this study was to assess cortisol as a biological and diagnostic marker in patients with bacterial meningitis.