Quantitative Culture of Bronchoalveolar Lavage in Diagnosis of Ventilator-Associated Pneumonia

Abstract

Background: Ventilator-associated pneumonia (VAP) is one of the most common hospital-acquired infections in patients hospitalized in intensive care unit (ICU). The aims of this study were to evaluate quantitative culture of bronchoalveolar lavage (BAL) in the diagnosis of VAP comparing with clinical pulmonary infection score (CPIS), and to determine positive and negative predictive values of the test.

Methods: A total of 209 samples were taken from the patients hospitalized in ICU with clinical suspicion on VAP, along with the CPIS. As the cut-off value of test, quantity of 10⁴ colony-forming unit (CFU)/mL was taken, according to Centers for Disease Control and Prevention (CDC) recommendations.

Results: Positive culture has been found in 142 patients (68%). The most common isolates were Acinetobacter baumanii in 49 (34.5%) patients, Klebisella pneumoniae in 31 (21.8%), Pseudomonas aeruginosa in 14 (9.9%), Staphylococcus aureus in eight (5.6%), Serratia marcensens in seven (4.9%), Escherichia coli in four (2.8%), other Enterobacteriaceae in five (3.5%), Pseudomonas spp in three (2.2%), Candida albicans in two (1.4%), and mixed infection in 19 patients (13.4%). In our study, sensitivity of the quantitative culture of BAL was 91%, specificity was 70%, positive predictive value was 80% and negative predictive value was 85%.

Conclusions: Quantitative culture of BAL can be useful in VAP diagnosis in patients hospitalized in the ICU, helping in the discrimination between colonization and the infection.




Clin Infect Immun. 2019;4(1):1-5
doi: https://doi.org/10.14740/cii72