title: Fulminant community-acquired Acinetobacter baumannii pneumonia as a distinct clinical syndrome.
abstract: OBJECTIVE
  Acinetobacter baumannii (AB) is an important cause of hospital-acquired pneumonia (HAP), and an uncommon but important cause of community-acquired pneumonia (CAP) with high mortality. To better characterize CAP-AB, we compared its clinical features and outcomes with a control group of HAP-AB patients.
  
  
  METHODS
  This is a retrospective case-control study comparing CAP-AB and HAP-AB patients, which was performed at United Christian Hospital between July 2000 and December 2003.
  
  
  RESULTS
  There were 19 cases of CAP-AB and 74 cases of HAP-AB. When compared with the HAP-AB group, the CAP-AB group had more ever-smokers (84.3% vs 55.4%, respectively; p = 0.031), more COPD patients (63.2% vs 29.7%, respectively; p = 0.014), and fewer median days of hospitalization (HAP-AB group, median, 0 days; CAP-AB group, 0 days [range, 0 to 30 days]; p = 0.049) in the previous year. The CAP-AB group had more patients with positive blood culture findings (31.6% vs 0%, respectively; p < 0.001), a higher frequency of ARDS (84.2% vs 17.6%, respectively; p < 0.001), and disseminated intravascular coagulation (DIC) (57.9% vs 8.1%, respectively; p < 0.001). The median survival time was only 8 days in the CAP-AB group, vs 103 days in the HAP-AB group (p = 0.003). Factors associated with the higher mortality in the CAP-AB group included the presence of AB bacteremia (p = 0.040), platelet count of < 120 x 10(9) cells/L (p = 0.026), pH < 7.35 on presentation (p = 0.047), and the presence of DIC (p = 0.004).
  
  
  CONCLUSIONS
  CAP-AB appears to be a unique clinical entity with a high incidence of bacteremia, ARDS, DIC, and death, when compared to HAP-AB. Further studies are needed to investigate the mechanism of the fulminant nature of CAP-AB.
authors.affiliation: Department of Medicine and Geriatrics, United Christian Hospital, Hong Kong SAR, Peoples Republic of China.
authors.forename: Wah-Shing
authors.initials: WS
authors.lastname: Leung
authors.forename: Chung-Ming
authors.initials: CM
authors.lastname: Chu
authors.forename: Kay-Yang
authors.initials: KY
authors.lastname: Tsang
authors.forename: Fu-Hang
authors.initials: FH
authors.lastname: Lo
authors.forename: King-Fan
authors.initials: KF
authors.lastname: Lo
authors.forename: Pak-Leung
authors.initials: PL
authors.lastname: Ho
mesh_terms: D000151:Acinetobacter Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000302:isolation & purification; D000208:Acute Disease; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D008297:Male; D018410:Pneumonia, Bacterial / Q000453:epidemiology* / Q000382:microbiology; D011379:Prognosis; D012189:Retrospective Studies; D012720:Severity of Illness Index; D015996:Survival Rate
chemical_list: D000900:Anti-Bacterial Agents