Bacterial agents of lower respiratory tract infections (LRTIs), beta-lactamase production, and resistance to antibiotics in elderly people

This study determined the etiology of lower respiratory tract infections in the elderly and assessed whether the growth of beta -lactamase producing b acteria is particularly favoured in these patients. Between December 1998 a nd May 1999, 187 patients with community-acquired pneumonia (CAP), and 887 patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) were enrolled. The mean age was 74 years (range of 65-94 year). Sp utum and bronchial aspirate for microbiological investigation were obtained . Besides organisms commonly involved in bacterial infections of the lower respiratory tract (i.e. Streptococcus pneumoniae, Haemophilus influenzae, a nd Moraxella catarrhalis), Enterobacteriaceae and Pseudomonas spp. were als o found. A high percentage of these bacteria were p-lactamase producers. Th ese data along with the clinical presentation, severity of infection, and e pidemiological knowledge, might represent a guide for the choice of empiric antimicrobial treatment. (C) 2000 Elsevier Science B.V. All rights reserve d.