Acinetobacter baumannii (AB) is a Gram-negative coccobacillus that is ubiquitous in fresh water and soil, and is also found frequently as a skin and throat commensal in humans. It is well-known because of the development of multiple drug resis-tance2″ and as an important cause of hospital-acquired pneumonia (HAP). anti allergy drugs
It is also increasingly recognized as an uncommon but important cause of community-acquired pneumonia (CAP). CAP-AB appears to be characterized by a fulminant course, with an acute onset of dyspnea, cough, and fever that rapidly progresses to respiratory failure and shock. The mortality rate from CAP-AB is high (40 to 64%), and it appears to be higher than the overall mortality rate (24%) resulting from severe CAP. However, these case series did not have any control group to which the clinical features and outcomes of CAP-AB could be compared. In order to better characterize CAP-AB, we performed a retrospective study of CAP-AB, and compared its clinical features and outcomes with a control group comprising patients with HAP-AB.
This is a retrospective case-control study comparing CAP-AB patients with a control group of HAP-AB patients at United Christian Hospital, which is a regional hospital with 1,200 acute care beds and serving a population of approximately 500,000 persons in Hong Kong. We systematically searched the computer database of our microbiology laboratory for patients with positive culture findings for AB between July 2000 and December 2003. We determined whether they were eligible for the study using the criteria listed below. We then abstracted the hospital records of these patients using a standardized database. Only cases of CAP-AB and HAP-AB were included. This study was approved by the Institutional Review Board at the United Christian Hospital. Pneumonia was defined by clinical and radiographic criteria, as described by the Centers for Disease Control and Prevention. Pneumonia was considered to be CAP if it was acquired outside a hospital or nursing home and the patient had not been hospitalized in the month before the development of pneumonia.