Aerobic Gram-negative Bacillary Pneumonia.

Gram-negative bacilli (GNB) are a common cause of severe hospital-acquired pneumonia. Due to changes in the health care environment and selective antimicrobial pressure, these bacteria also are becoming a more common cause of pneumonia in venues outside of the traditional hospital setting and are increasingly resistant to antimicrobial agents. Risk factors for acquisition of GNB allow the clinician to efficiently identify patients who are likely to have pneumonia due to these pathogens. Available diagnostic techniques have a limited capacity to accurately detect GNB pulmonary infection. Yet, a pathogen specific diagnosis and knowledge of local resistance patterns are quintessential elements in formulating an effective treatment plan. This article reviews the epidemiologic characteristics, pathogenesis, and current management issues of GNB pneumonia.