Differences in the definition, demographics, risk factors, etiology, and treatment for health care-associated pneumonia (HCAP) versus community-acquired pneumonia (CAP) are discussed.Summary
Health care-associated infections (HCAI) represent a population of outpatients with exposure to health care institutions and procedures who develop nosocomial-like infections. HCAI are etiologically similar to nosocomial infections with gram-negative organisms, methicillin-resistant Staphylococcus aureus (MRSA), and multidrug-resistant (MDR) pathogens predominating. These patients are ambulatory, community residents who often present to hospital emergency departments as would patients with community-acquired infection. Although many differences between HCAI and community-acquired infections, as well as HCAP and CAP, remain to be elucidated, the emerging evidence has identified multiple and important differences. Because of etiologic differences between CAP and HCAP, treatment strategies necessarily differ. Mistaking HCAP for CAP may result in the use of inappropriate empirical therapy, which is an established source of treatment failure, morbidity, and mortality. Thus, it is essential for physicians to be capable of recognizing risk factors for HCAI and HCAP as well as competently select and implement appropriate treatment strategies.Conclusion
The etiologic differences between HCAP and CAP require different treatment strategies. No clinical or demographic characteristics nor signs and symptoms distinguish HCAP from CAP. Rather, physicians must rely on a thorough and careful history of each patient as well as their own clinical judgment.