title: Bronchoalveolar lavage findings in severe community-acquired pneumonia due to Legionella pneumophila serogroup 1.
abstract: BACKGROUND
  No specific data are available in the literature on the bronchoalveolar Lavage (BAL) findings of Legionella pneumophila pneumonia. We report on the cytological and immunophenotypical BAL data of three immunocompetent patients with severe community-acquired pneumonia due to L. pneumophila serogroup 1.
  
  
  METHODS
  Retrospective chart review. The microbiologial diagnosis was obtained by BAL culture or/and urinary antigen assay.
  
  
  RESULTS
  All patients presented with high-grade fever, bilateral chest infiltrates and severe respiratory failure requiring ventilatory support. The cytological BAL pattern at presentation showed in all patients the association of a marked neutrophilia with a variable but remarkable percentage of lymphoblasts. Increased levels of activated T-Lymphocytes (both HLA-DR + and CD25 + cells) and, in 2 out of 3 patients, of T-cells bearing the gamma/delta T-cell receptor were the main immunophenotypical findings on flow cytometric analysis.
  
  
  CONCLUSIONS
  We suggest that the association of lymphoblasts with a marked neutrophilia in BAL fluid of patients with a clinical-radiological setting compatible with acute pneumonia should suggest L. pneumophila as a possible etiologic agent.
authors.affiliation: Maggiore Hospital, Largo Nigrisoli 2, 40133 Bologna, Italy. rocco.trisolini@ausl.bologna.it
authors.forename: Rocco
authors.initials: R
authors.lastname: Trisolini
authors.forename: Luigi
authors.initials: L
authors.lastname: Lazzari Agli
authors.forename: Alessandra
authors.initials: A
authors.lastname: Cancellieri
authors.forename: Leonarda
authors.initials: L
authors.lastname: Procaccio
authors.forename: Piero
authors.initials: P
authors.lastname: Candoli
authors.forename: Marco
authors.initials: M
authors.lastname: Alifano
authors.forename: Marco
authors.initials: M
authors.lastname: Patelli
mesh_terms: D000368:Aged; D000942:Antigens, Bacterial / Q000652:urine; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000276:immunology*; D017714:Community-Acquired Infections / Q000175:diagnosis; D006801:Humans; D016130:Immunophenotyping; D016952:Legionella pneumophila / Q000145:classification* / Q000276:immunology; D007877:Legionnaires' Disease / Q000175:diagnosis* / Q000276:immunology; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000473:pathology; D012189:Retrospective Studies; D016176:T-Lymphocyte Subsets / Q000276:immunology
chemical_list: D000942:Antigens, Bacterial