Purpose of review: Nosocomial infections are an emerging threat. Available solutions are limited due to the multidrug-resistance pattern of the pathogens. Macrolides modulate the immune function of the host and may be active in this setting.
Recent findings: Findings of in-vitro and experimental animal studies are presented. Clinical studies of community-acquired pneumonia (CAP) and ventilator-associated pneumonia (VAP) are described.
Summary: Macrolides decrease production of proinflammatory cytokines by circulating monocytes and by alveolar macrophages and decrease apoptosis of circulating lymphocytes in animal models of acute infections. They also inhibit gene expression of proteins participating in quorum sensing of Pseudomonas aeruginosa. Retrospective cohort studies indicate that addition of a macrolide significantly improves outcome in severe CAP. One randomized, double-blind, clinical study is available. This involves patients with VAP allocated to placebo or intravenous clarithromycin 1 g once daily for 3 days. Clarithromycin treatment significantly decreased time to resolution of VAP and time until weaning from mechanical ventilation. The described findings are promising for the use of macrolides in nosocomial infections.