Does health care associated pneumonia really exist?

The most recent ATS guidelines for nosocomial pneumonia of 2005 describe a new clinical category of patients, Health Care-Associated Pneumonia which includes a number of very heterogeneous conditions possibly associated with a high risk of multi-drug resistant (MDR) infections and of mortality. This paper aims at reviewing the current literature on HCAP and examines the controversial issues of HCAP etiology and outcomes, underlining the need of a profound revision of the HCAP concept in the face of the poor and contrasting scientific evidence supporting its basis.