Risk factors and severity scores in hospitalized patients with community-acquired pneumonia: prediction of severity and mortality.

Morbidity and mortality in patients with moderate to severe community-acquired pneumonia (CAP) is a global problem, and CAP is a leading cause of death due to infectious diseases. Prompt initiation of expanded-spectrum antimicrobials is essential for the prevention of unnecessary mortality and complications in patients, particularly in the elderly and other at-risk populations, and the treatment decisions made by practitioners have important implications for healthcare systems when hospitalization is required. Empirical antimicrobial treatment and the appropriate management of CAP patients will initially require the proper assessment of severity and patient risk for increased mortality, as well as risk factors for difficult-to-treat bacteria. This review will examine risk factors and scoring systems that may be predictive of moderate to severe CAP, which is often linked to increased risk of mortality. Understanding and recognizing potential risk factors will allow practitioners to proactively identify patients at the highest risk for severe illness or complications, thereby, guiding site-of-care decisions, as well as the choices for empiric antibiotic regimens. The decision to hospitalize a patient with CAP should include not only a clinical perspective and laboratory and radiographic findings, but also at least one objective tool of risk assessment, all in combination with sound clinical judgment.