title: Bronchoalveolar lavage cytological alveolar damage in patients with severe pneumonia.
abstract: BACKGROUND
  Histological examination of lung specimens from patients with pneumonia shows the presence of desquamated pneumocytes and erythrophages. We hypothesized that these modifications should also be present in bronchoalveolar lavage fluid (BAL) from patients with hospital-acquired pneumonia.
  
  
  METHODS
  We conducted a prospective study in mechanically ventilated patients with clinical suspicion of pneumonia. Patients were classified as having hospital-acquired pneumonia or not, in accordance with the quantitative microbiological cultures of respiratory tract specimens. A group of severe community-acquired pneumonias requiring mechanical ventilation during the same period was used for comparison. A specimen of BAL (20 ml) was taken for cytological analysis. A semiquantitative analysis of the dominant leukocyte population, the presence of erythrophages/siderophages and desquamated type II pneumocytes was performed.
  
  
  RESULTS
  In patients with confirmed hospital-acquired pneumonia, we found that 13 out of 39 patients (33.3%) had erythrophages/siderophages in BAL, 18 (46.2%) had desquamated pneumocytes and 8 (20.5%) fulfilled both criteria. Among the patients with community-acquired pneumonia, 7 out of 15 (46.7%) had erythrophages/siderophages and 6 (40%) had desquamated pneumocytes on BAL cytology. Only four (26.7%) fulfilled both criteria. No patient without hospital-acquired pneumonia had erythrophages/siderophages and only 3 out of 18 (16.7%) had desquamated pneumocytes on BAL cytology.
  
  
  CONCLUSIONS
  Cytological analysis of BAL from patients with pneumonia (either community-acquired or hospital-acquired) shows elements of cytological alveolar damage as hemorrhage and desquamated type II pneumocytes much more frequently than in BAL from patients without pneumonia. These elements had a high specificity for an infectious cause of pulmonary infiltrates but low specificity. These lesions could serve as an adjunct to diagnosis in patients suspected of having ventilator-associated pneumonia.
authors.affiliation: Department of Critical Care, Hôpital Antoine Beclere, Assistance Publique-Hôpitaux de Paris, 157 rue de la porte de Trivaux, 92140 Clamart, Paris, France.
authors.forename: Bogdan
authors.initials: B
authors.lastname: Grigoriu
authors.forename: Frédéric
authors.initials: F
authors.lastname: Jacobs
authors.forename: Fabienne
authors.initials: F
authors.lastname: Beuzen
authors.forename: Rony
authors.initials: R
authors.lastname: El Khoury
authors.forename: Olivier
authors.initials: O
authors.lastname: Axler
authors.forename: Francois G
authors.initials: FG
authors.lastname: Brivet
authors.forename: Frédérique
authors.initials: F
authors.lastname: Capron
mesh_terms: D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology*; D017714:Community-Acquired Infections / Q000473:pathology; D003428:Cross Infection / Q000473:pathology*; D006470:Hemorrhage / Q000175:diagnosis; D006801:Humans; D008168:Lung / Q000473:pathology*; D011014:Pneumonia / Q000145:classification / Q000473:pathology*; D011446:Prospective Studies; D015203:Reproducibility of Results