Community-acquired acute bacterial meningitis in older people in Spain

Abstract number: P714

Sulleiro E., Rodriguez D., Amaya-Villar R., Garcia-Cabrera E., Fernández-Viladrich P., Molinos S., Coloma A., Fontanals D., Catalán P., Meseguer M.A., Colomina J., Almirante B.

Objective: Older age is considered to be an important risk factor for unfavourable outcome in community-acquired Acute Bacterial Meningitis (ca-ABM). The aim of this study is to describe clinical characteristics and outcome of ca-ABM in patients over 65 years compared to younger ones

Methods: A prospective multicentre study of ca-ABM was carried out in 9 Spanish hospitals included in the REIPI programme (Spanish Network for the Research in Infectious Diseases) between 1/11/2003 and 30/07/2006. Patients were diagnosed on the basis of a compatible clinical, biological and microbiological data. An adverse clinical outcome was defined as death or cure with disabilities.

Results: 415 patients were diagnosed with ca-ABM, 293 <65 years-old (median age: 29.8, range: 0–64) and 122 65 years years-old (median age: 74.4, range: 65–91). Among patients over 65 years Streptococcus pneumoniae (Sp) was the most frequent aetiology (44.3%), followed by Listeria monocytogenes (Lm) (20.5%). Lm was significantly more frequent in this group compared to younger patients (20.5% vs 7.5%, p < 0.05) among which Neisseria meningitidis (Nm) was the most common aetiology (12.3% vs 32.1%, p < 0.05). Diabetes (28% vs 6%, p < 0.05) and a distant foci of infection (12.7% vs 3.9%, p < 0.05) were more frequent in elderly who more often presented the classic triad of fever, neck stiffness and altered mental status (50% vs 39%, p = 0.021), a GSC (Glasgow Score Come) <14 (79.3% vs 50.2%, p < 0.05), focal neurological deficits (21.2% vs 11%, p = 0.007) and respiratory failure (23.7% vs 11%, p < 0.05). Elderly cohort was treated with third-generation cephalosporin associated to ampicillin in 41% of the cases compared to only 18% of the cases in patients under 65 years (p < 0.05). Among patients over 65 years hemodynamic failure (25.4% vs 12%, p < 0.05), a GSC decrease on evolution (26.3% vs 13.8%, p < 0.05) and an adverse clinical outcome (45% vs 20%, p < 0.05) were significantly more frequent. Mortality rate was higher among adults over 65 years (29% vs 8%, p < 0.05).

Conclusions: ca-ABM in patients over 65 years is predominantly due to Sp followed by Lm which is significantly more frequent in this group. Ca-ABM in the elderly cohort significantly present with more severe clinical features and adverse evolution being overall mortality in this group significantly higher.