Regular Article| Volume 95, ISSUE 11, P885-890, November 2001

Quantitative culture of bronchoalveolar lavage fluid in community-acquired lower respiratory tract infections

      This paper is only available as a PDF. To read, Please Download here.


      To evaluate the diagnostic value of quantitative bacterial culture of bronchoalveolar lavage (BAL) fluid obtained by fibreoptic bronchoscopy, 67 consecutive immunocompetent adult patients admitted to hospital with community-acquired lower respiratory tract infections from September 1997 to May 1998 were investigated. Results were compared to the findings in eight healthy control persons investigated in February 1998. There was no difference between study patients and control persons when quantitative culture of total cumulative bacterial findings or bacteria categorized as members of the oropharyngeal normal flora were compared. The culture of normal flora in bronchial washings probably reflects contamination of the lower airways with secretions from upper airways by the fibreoptic procedure itself, as fractionated sampling showed a 10-fold reduction in quantitative culture results when a primary bronchial washing was compared to a secondary sampling from the same bronchus in the control group. Twenty-four (36%) of 67 patients were cultured as positive in the study group while all control persons were cultured as negative for bacteria categorized as potential pathogens. With a threshold value for positive culture of 104cfu ml−1the specificity of lavage culture of potential pathogenic bacteria in relation to actual lower airway infection was 100%. Therefore, quantitative bacterial culture of potential pathogenic bacteria in BAL fluid is very specific but only positive in about one-third of unselected immunocompetent adult patients with a lower respiratory tract infection.




        • Chastre J
        • Trouillet JL
        The role of bronchoscopy in the diagnosis of nosocomial bacterial infections.
        J Bronchology. 1997; 4: 54-67
        • Cantral DE
        • Tape TG
        • Reed EC
        • Spurzem JR
        • Rennard S
        • Thompson AB
        Quantitative culture of bronchoalveolar lavage fluid for the diagnosis of bacterial pneumonia.
        Am J Med. 1993; 95: 601-607
        • Niederman MS
        • Bass JB
        • Campbell GD
        Guidelines for the initial management of adults with community-acquired pneumonia: diagnosis, assessment of severity, and initial antimicrobial therapy.
        Am Rev Resp Dis. 1993; 148: 1418-1426
        • Anthonisen N
        • Manfreda J
        • Warren C PW
        • Hersfield ES
        • Harding G KM
        • Nelson NA
        Antibiotic therapy in exacerbations of chronic obstructive pulmonary disease.
        Ann Int Med. 1987; 106: 196-204
        • Thorpe JE
        • Baughman RP
        • Frame PT
        • Wesseler TA
        • Staneck JL
        Bronchoalveolar lavage for diagnosing acute bacterial pneumonia.
        J Infect Dis. 1987; 155: 855-861
        • Kahn FW
        • Jones JM
        Diagnosing bacterial respiratory infection by bronchoalveolar lavage.
        J Infect Dis. 1987; 155: 862-869
        • Pang JA
        • Cheng A FB
        • Chan HS
        • French GL
        Special precautions reduce oropharyngeal contamination in bronchoalveolar lavage for bacteriological studies.
        Lung. 1989; 167: 261-267
        • Dalhoff K
        • Braun J
        • Hollandt H
        • Lipp R
        • Wießmann K-J
        • Marre R
        Diagnostic value of bronchoalveolar lavage in patients with opportunistic and nonopportunistic bacterial pneumonia.
        Infection. 1993; 210: 291-297
        • Marrie TF
        • Durant H
        • Yates L
        Community-acquired pneumonia requiring hospitalization: 5-year prospective study.
        Rev Infect Dis. 1989; 11: 589-599
        • Ruiz M
        • Ewig S
        • Marcos MA
        Etiology of community-acquired pneumonia: Impact of age, comorbidity and severity.
        Am J Respir Crit Care Med. 1999; 160: 397-405