ABSTRACT
Until 1970, clinicians had generally ignored evidence that Acinetobacter spp. could be the microbiological cause of pneumonia, and considered these organisms to be of relatively low virulence in humans. This chapter reviews published studies on the epidemiology and clinical characteristics of nosocomial pneumonia caused by Acinetobacter spp. in critically ill patients hospitalised in intensive care units (ICUs). The importance of using such bronchoscopic techniques in epidemiological studies of nosocomial pneumonia caused by Acinetobacter spp. and other non-fermenting Gram-negative bacteria is illustrated by a study performed by our group at Bichat Hospital in Paris. The overall mortality of patients without pneumonia who received no specific antimicrobial treatment was 28%, compared with 75% in patients who developed true pneumonia caused by Acinetobacter or Pseudomonas spp. Accurate data on the epidemiology of A. baumannii nosocomial pneumonia in critically ill patients cared for in the ICU are limited by the lack of a gold standard for diagnosis, especially in patients undergoing mechanical ventilation.
