title: Improving the Diagnosis of Legionella Pneumonia within a Healthcare System through a Systematic Consultation and Testing Program.
abstract: Legionella testing is not recommended for all patients with pneumonia, but rather for particular patient subgroups. As a result, the overall incidence of Legionella pneumonia may be underestimated.
  
  
  
  To determine the incidence of Legionella pneumonia in a veteran population in an endemic area after introduction of a systematic infectious diseases consultation and testing program.
  
  
  
  In response to a 2011-2012 outbreak, the VA Pittsburgh Healthcare System mandated infectious diseases consultations and testing for Legionella by urine antigen and sputum culture in all patients with pneumonia.
  
  
  
  Between January 2013 and December 2015, 1,579 cases of pneumonia were identified. The incidence of pneumonia was 788/100,000 veterans per year, including 352/100,000 veterans per year and 436/100,000 veterans per year with community-associated pneumonia (CAP) and health care-associated pneumonia, respectively. Ninety-eight percent of patients with suspected pneumonia were tested for Legionella by at least one method. Legionella accounted for 1% of pneumonia cases (n = 16), including 1.7% (12/706) and 0.6% (4/873) of CAP and health care-associated pneumonia, respectively. The yearly incidences of Legionella pneumonia and Legionella CAP were 7.99 and 5.99/100,000 veterans, respectively. The sensitivities of urine antigen and sputum culture were 81% and 60%, respectively; the specificity of urine antigen was >99.97%. Urine antigen testing and Legionella cultures increased by 65% and 330%, respectively, after introduction of our program.
  
  
  
  Systematic testing of veterans in an endemic area revealed a higher incidence of Legionella pneumonia and CAP than previously reported. Widespread urine antigen testing was not limited by false positivity.
authors.affiliation: 1 Infectious Diseases Section.|2 Division of Infectious Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Brooke K
authors.identifier: 0000-0002-3404-9115
authors.initials: BK
authors.lastname: Decker
authors.affiliation: 3 VA Pittsburgh Healthcare System, Pittsburgh, Pennsylvania; and.
authors.forename: Patricia L
authors.initials: PL
authors.lastname: Harris
authors.affiliation: 2 Division of Infectious Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Robert R
authors.initials: RR
authors.lastname: Muder
authors.affiliation: 1 Infectious Diseases Section.|2 Division of Infectious Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Jae H
authors.initials: JH
authors.lastname: Hong
authors.affiliation: 1 Infectious Diseases Section.|2 Division of Infectious Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Nina
authors.initials: N
authors.lastname: Singh
authors.affiliation: 3 VA Pittsburgh Healthcare System, Pittsburgh, Pennsylvania; and.
authors.forename: Ali F
authors.initials: AF
authors.lastname: Sonel
authors.affiliation: 1 Infectious Diseases Section.|2 Division of Infectious Diseases, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Cornelius J
authors.initials: CJ
authors.lastname: Clancy
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D007875:Legionella / Q000235:genetics / Q000302:isolation & purification*; D007877:Legionnaires' Disease / Q000175:diagnosis / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D010414:Pennsylvania / Q000453:epidemiology; D018410:Pneumonia, Bacterial / Q000453:epidemiology*; D012017:Referral and Consultation; D012680:Sensitivity and Specificity; D013183:Sputum / Q000382:microbiology; D014556:Urine / Q000382:microbiology; D014728:Veterans / Q000706:statistics & numerical data*
keywords: Legionella; Legionnaires’ disease; diagnostic testing; incidence; pneumonia