What Is New in Antibiotic Therapy in Community-Acquired Pneumonia? An Evidence-Based Approach Focusing on Combined Therapy

Despite all published literature, controversies remain about the optimal antibiotic treatment in community-acquired pneumonia. The most debated issue is whether it is necessary to empirically start one or two antibiotics, i.e. whether or not to cover atypical agents. A review of the literature published from 2005 to present was completed, searching for new insights in antibiotic treatment in community-acquired pneumonia (CAP) focusing on monotherapy versus combined therapy. Forty-one articles were identified enrolling outpatients, and patients admitted to the ward and to the intensive care unit: 11 were meta-analyses, 8 clinical trials and 22 observational—prospective and retrospective—studies. Although controversies remain in the treatment of CAP, the use of combination therapy seems to be associated with a lower mortality in case of severe CAP that requires intensive care unit (ICU) admission, especially when a beta-lactam–macrolide association is delivered. Moreover, combination therapy is associated with better outcomes—although not always with a lower mortality—in cases of non-ICU patients with risk factors for a poor outcome, bacteraemic pneumococcal pneumonia and high suspicion of infection by atypical agents. In this setting, it appears that the best choice of treatment may be a beta-lactam–macrolide regimen.