Severe community-acquired pneumonia.

Community-acquired pneumonia (CAP) is the leading cause of death from infectious diseases in the United States. It accounts for 500,000 hospitalizations and 45,000 deaths each year, and it represents one of the most common causes of ICU admission. The mortality rate due to severe CAP has shown little improvement over the past few years, with rates as high as 58% when patients were admitted to the ICU. Significant interest has focused on the sickest patients who have pneumonia treated in the ICU, regarding identification of need for ICU admission and therapies directed to improve outcomes in patients who have severe CAP. This article reviews epidemiologic, microbiologic, therapeutic, preventive, and outcomes data in patients who have CAP in the ICU.