title: A worldwide perspective of atypical pathogens in community-acquired pneumonia.
abstract: BACKGROUND
  Controversy still exists in the international literature regarding the need to use antimicrobials covering atypical pathogens when initially treating hospitalized patients with community-acquired pneumonia (CAP). In different regions of the world, monotherapy with a beta-lactam antimicrobial is common.
  
  
  OBJECTIVE
  We sought to correlate the incidence of CAP due to atypical pathogens in different regions of the world with the proportion of patients treated with an atypical regimen in those same regions. In addition, we sought to compare clinical outcomes of patients with CAP treated with and without atypical coverage.
  
  
  METHODS
  A secondary analysis was performed using two comprehensive international databases. World regions were defined as North America (I), Europe (II), Latin America (III), and Asia and Africa (IV). Time to reach clinical stability, length of hospital stay, and mortality were compared between patients treated with and without atypical coverage.
  
  
  RESULTS
  The incidence of CAP due to atypical pathogens from 4,337 patients was 22, 28, 21, and 20% in regions I-IV, respectively. The proportion of patients treated with atypical coverage from 2,208 patients was 91, 74, 53, and 10% in regions I-IV, respectively. Patients treated with atypical coverage had decreased time to clinical stability (3.7 vs. 3.2 d, p < 0.001), decreased length of stay (7.1 vs. 6.1 d, p < 0.01), decreased total mortality (11.1 vs. 7%, p < 0.01), and decreased CAP-related mortality (6.4 vs. 3.8%, p = 0.05).
  
  
  CONCLUSIONS
  The significant global presence of atypical pathogens and the better outcomes associated with antimicrobial regimens with atypical coverage support empiric therapy for all hospitalized patients with CAP with a regimen that covers atypical pathogens.
authors.affiliation: Division of Infectious Diseases, University of Louisville, Louisville, KY 40292, USA. f.arnold@louisville.edu
authors.forename: Forest W
authors.initials: FW
authors.lastname: Arnold
authors.forename: James T
authors.initials: JT
authors.lastname: Summersgill
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Lajoie
authors.forename: Paula
authors.initials: P
authors.lastname: Peyrani
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Marrie
authors.forename: Paolo
authors.initials: P
authors.lastname: Rossi
authors.forename: Francesco
authors.initials: F
authors.lastname: Blasi
authors.forename: Patricia
authors.initials: P
authors.lastname: Fernandez
authors.forename: Thomas M
authors.initials: TM
authors.lastname: File
authors.forename: Jordi
authors.initials: J
authors.lastname: Rello
authors.forename: Rosario
authors.initials: R
authors.lastname: Menendez
authors.forename: Lucia
authors.initials: L
authors.lastname: Marzoratti
authors.forename: Carlos M
authors.initials: CM
authors.lastname: Luna
authors.forename: Julio A
authors.initials: JA
authors.lastname: Ramirez
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001419:Bacteria / Q000187:drug effects / Q000302:isolation & purification; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology*; D016208:Databases, Factual; D014943:Global Health; D006801:Humans; D015994:Incidence; D018410:Pneumonia, Bacterial / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology*; D012189:Retrospective Studies
chemical_list: D000900:Anti-Bacterial Agents