The emergence, in the 1960s, of facultative enteric Gramnegative bacilli (GNB) as the predominant pathogen(s) in hospital-acquired (HA) infections has been well documented. This rise has been attributed to intensive use of antibiotics1 and the realization that our hospitalized patients are becoming more susceptible to infection.2 Their defense mechanisms are altered not only by chronic underlying diseases (diabetes mellitus, malignancy, alcoholism, renal failure), but also by therapy for some of these diseases (steroids, cytotoxic drugs), instrumentation (endotracheal intubation, tracheostomy, intravenous catheters, urinary-bladder catheters), and surgery.
On the other hand, little attention has been given to the relative role these organisms play in community-acquired (CA) infections. A CA infection is one that is clinically active or incubating at the time of admission and judged not to have been acquired during a recent hospitalization. With this definition in mind, we reviewed the literature before, during, and after the 1960s to