Healthcare-associated pneumonia: Diagnostic criteria and distinction from community-acquired pneumonia

Background: Traditionally, pneumonia developing in patients who receive healthcare services in the outpatient environment has been classified as community-acquired pneumonia (CAP). However, recent investigations suggest that this type of infection, known as healthcare-associated pneumonia (HCAP), is distinct from CAP in terms of its epidemiology, etiology, and risk for infection with multidrug-resistant (MDR) pathogens. Methods: A Medline literature review of available clinical studies using the term HCAP was conducted to determine outcomes compared to CAP and effective empiric treatment strategies. Results: Analysis of multi-institutional clinical data showed that mortality in hospitalized patients with HCAP is greater than that in CAP, and patients with HCAP received inappropriate initial empiric antibiotic treatment more frequently than CAP patients. The bacterial pathogens associated with HCAP also differed from CAP with potentially MDR Gram-positive and Gram-negative bacteria being more common in HCAP. Conclusions: All patients hospitalized with suspected HCAP should be evaluated for their underlying risk of infection with MDR pathogens. Because HCAP is similar to hospital-acquired pneumonia (HAP), both clinically and etiologically, it should be treated as HAP until culture data become available. (C) 2011 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.