title: Disease severity prediction for nursing home-acquired pneumonia in the emergency department.
abstract: BACKGROUND
  Prediction rules exist for the assessment of community-acquired pneumonia but their use in nursing home-acquired pneumonia (NHAP) remains undefined. The objectives of this study were to compare the prognostic ability for severe NHAP of five prediction rules (PSI, CURB-65, M-ATS, R-ATS, España rule), and to evaluate their usefulness to identify patients with less severe disease in the emergency department for outpatient care.
  
  
  METHODS
  A prospective observational study of consecutive NHAP patients was conducted at a university teaching hospital emergency department in Hong Kong between January 2004 and June 2005. The primary outcome was severe pneumonia (defined as combined 30-day mortality and/or intensive care unit (ICU) admission).
  
  
  RESULTS
  767 consecutive NHAP patients were included. Mean (SD) age was 83.4 (9.0) years; 350 (45.6%) were male and 644 (84.0%) had coexisting illness. 95 patients died within 30 days (12.4%), five patients were admitted to the ICU (0.7%) and 98 patients had severe pneumonia (12.8%). Sensitivity and specificity of each decision rule ranged from 37.8% to 95.9% and 15.1% to 87.6% respectively. The overall predictive performance of each rule was between 0.627 and 0.712. The negative likelihood ratios of PSI (0.27) and CURB-65 (0.23) were lower than M-ATS (0.71), R-ATS (0.45) and España (0.39). After excluding 204 patients with either poor functional status or those >90 years of age, sensitivities of M-ATS (96.0%) and R-ATS (100%) improved greatly with negative likelihood ratios of <0.1.
  
  
  CONCLUSIONS
  PSI and CURB-65 are useful for identification of patients with less severe NHAP.
authors.affiliation: Accident and Emergency Medicine Academic Unit, Chinese University of Hong Kong, Trauma & Emergency Centre, Prince of Wales Hospital, Shatin, NT, Hong Kong SAR.
authors.forename: S Y
authors.initials: SY
authors.lastname: Man
authors.forename: C A
authors.initials: CA
authors.lastname: Graham
authors.forename: S S W
authors.initials: SS
authors.lastname: Chan
authors.forename: P S K
authors.initials: PS
authors.lastname: Mak
authors.forename: A H Y
authors.initials: AH
authors.lastname: Yu
authors.forename: C S K
authors.initials: CS
authors.lastname: Cheung
authors.forename: P S Y
authors.initials: PS
authors.lastname: Cheung
authors.forename: G
authors.initials: G
authors.lastname: Lui
authors.forename: N
authors.initials: N
authors.lastname: Lee
authors.forename: M
authors.initials: M
authors.lastname: Chan
authors.forename: M
authors.initials: M
authors.lastname: Ip
authors.forename: T H
authors.initials: TH
authors.lastname: Rainer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017714:Community-Acquired Infections / Q000175:diagnosis; D003428:Cross Infection / Q000175:diagnosis* / Q000209:etiology; D004636:Emergency Service, Hospital; D005260:Female; D006723:Hong Kong; D006801:Humans; D008297:Male; D009735:Nursing Homes; D011014:Pneumonia / Q000175:diagnosis* / Q000209:etiology; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index