Korean J Intern Med.  2012 Jun;27(2):156-162. 10.3904/kjim.2012.27.2.156.

Bacterial Yield from Quantitative Cultures of Bronchoalveolar Lavage Fluid in Patients with Pneumonia on Antimicrobial Therapy

• Kim ES
• Kim EC
• Lee SM
• Yang SC
• Yoo CG
• Kim YW
• Han SK
• Yim JJ

• KMID: 1776542
• DOI: http://doi.org/10.3904/kjim.2012.27.2.156

Abstract

BACKGROUND/AIMS
Early diagnosis and appropriate antimicrobial choice are crucial when managing pneumonia patients, and quantitative culture of bronchoalveolar lavage (BAL) fluid is considered a useful method for identifying pneumonia pathogens. We evaluated the quantitative yield of BAL fluid bacterial cultures in patients being treated with antimicrobials and attempted to identify factors predictive of positive BAL cultures.
METHODS
Patients over 18 years old and whose BAL fluid was subjected to quantitative culture to identify the organism causative of pneumonia between January 1, 2005, and December 31, 2009, were included. We reviewed the results of BAL fluid bacterial cultures and the clinical records, laboratory tests, and radiographic findings of the patients.
RESULTS
BAL was performed on 340 patients with pneumonia. A positive BAL culture, defined as isolation of more than 10(4) colony forming units/mL bacteria, was documented in 18 (5.29%) patients. Of these, 9 bacteria isolated from 10 patients were classified as probable pathogens. The most frequently isolated bacteria were methicillin-resistant Staphylococcus aureus, Acinetobacter baumannii, and Pseudomonas aeruginosa. No independent predictive factor for positive BAL cultures was identified.
CONCLUSIONS
The yield of quantitative BAL fluid bacterial culture in patients already on antimicrobials was low. Clinicians should be cautious when performing a BAL culture in patients with pneumonia who are already on antimicrobials.

Keyword

Bronchoalveolar lavage; Pneumonia; Antimicrobials

MeSH Terms

Adult
Aged
Aged, 80 and over
Anti-Infective Agents/*therapeutic use
Bacteria/classification/*drug effects/*isolation & purification
Bronchoalveolar Lavage
Bronchoalveolar Lavage Fluid/*microbiology
Bronchoscopy
Chi-Square Distribution
Colony Count, Microbial
Drug Resistance, Multiple, Bacterial
Female
Humans
Logistic Models
Male
Microbial Sensitivity Tests
Middle Aged
Pneumonia, Bacterial/diagnosis/*drug therapy/microbiology
Predictive Value of Tests
Republic of Korea
Retrospective Studies
Treatment Outcome
Young Adult