title: [Concordance between two methods of bronchoalveolar lavage for the microbiological diagnosis of pneumonia in mechanically ventilated patients].
abstract: BACKGROUND
  Microbiological diagnosis of pneumonia allows the optimal use of antibiotics in mechanically ventilated patients. That is why samples of bronchoscopic bronchoalveolar lavage had been quantitatively cultivated, but this procedure is not always possible.
  
  
  OBJECTIVE
  To evaluate the microbiological concordance between respiratory samples obtained by non-bronchoscopic protected bronchoalveolar lavage compared to the bronchoscopic ones, and to find out whether concordance was affected by previous use of antibiotics or the time of pneumonia onset.
  
  
  METHODS
  Prospective study conducted at Hospital Universitario San Vicente de Paúl, in 38 patients with suspected pneumonia in mechanical ventilation. Bronchoalveolar lavage specimens were taken by two methods, the traditional one and non-bronchoscopic bronchoalveolar lavage, using a telescoping preformed tip catheter (Balcath). All samples were processed using conventional microbiologic protocols.
  
  
  RESULTS
  Considering flexible bronchoscopy with bronchoalveolar lavage as the gold standard, cultures allowed the identification of at least one respiratory pathogen in 60.5% of cases. Diagnostic agreement was achieved in 82% of patients and 79% of microbiologic isolates. Using the Cohen's kappa coefficient, general concordance between both methods was 0.76 [0.60-0.93]; but in those who received previously antibiotics was 0.26 [0.05-0.48], versus 1.0 in those who did not (p<0.0001). Concordance did not differ significantly when cases of early or late pneumonia were compared.
  
  
  CONCLUSIONS
  Concordance between non-bronchoscopic and bronchoscopic bronchoalveolar lavage is good in mechanically ventilated patients with pneumonia. However, the use of antibiotics previously, but not the time of pneumonia presentation, significantly decreases that concordance.
authors.affiliation: Grupo Investigador de Problemas en Enfermedades Infecciosas, Universidad de Antioquia, Medellín, Colombia. clamona@une.net.co
authors.forename: Lázaro Agustín
authors.initials: LA
authors.lastname: Vélez
authors.forename: Natalia
authors.initials: N
authors.lastname: Loaiza
authors.forename: Lina María
authors.initials: LM
authors.lastname: Gaviria
authors.forename: María Angélica
authors.initials: MA
authors.lastname: Maya
authors.forename: Zulma Vanessa
authors.initials: ZV
authors.lastname: Rueda
authors.forename: Luz Teresita
authors.initials: LT
authors.lastname: Correa
authors.forename: Jorge
authors.initials: J
authors.lastname: Ortega
authors.forename: Héctor
authors.initials: H
authors.lastname: Ortega
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D018893:Bronchoalveolar Lavage / Q000379:methods*; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology*; D001999:Bronchoscopy / Q000379:methods; D003428:Cross Infection / Q000382:microbiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000175:diagnosis* / Q000188:drug therapy / Q000209:etiology / Q000382:microbiology*; D011446:Prospective Studies; D015203:Reproducibility of Results; D012121:Respiration, Artificial / Q000009:adverse effects; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents