Antibacterial class is not obviously important in outpatient pneumonia: a meta-analysis.

The aim of the present study was to systematically compare outcomes between antibiotic classes in treating outpatient community-acquired pneumonia, with regard to antibacterials active against atypical organisms, as well as between various antibacterial classes with similar atypical coverage. A meta-analysis was performed on randomised controlled trials of antibacterials for community-acquired pneumonia in outpatients aged > or = 18 yrs. The studies were independently reviewed by two reviewers. Clinical success and mortality were compared between different oral antibiotic classes, and antibacterials with atypical coverage (macrolides and fluoroquinolones) were specifically compared with other antibacterials. In total, 13 eligible studies involving a total of 4,314 patients were included. The quality of the studies was variable. Five studied macrolides and fluoroquinolones, three macrolides and beta-lactams, three fluoroquinolones and beta-lactams and two cephalosporins versus beta-lactams/beta-lactamase inhibitors. No significant difference was detected regarding clinical success or mortality, regardless of atypical coverage or between antibacterial classes with similar atypical coverage. It was not possible to demonstrate any advantage of specific antibacterials for mild community-acquired pneumonia in relatively healthy outpatients. The need for coverage of atypical pathogens in this setting was not apparent. In mild-to-moderate cases of outpatient-treated community-acquired pneumonia, it might be most appropriate to select antibacterials according to side-effects, patient preferences, availability and cost.