Investigation of Bronchoscopy Associated Pseudo-infections

Abstract

Introduction: Bronchoscopy could lead to local spread of pre-existing infection, spread of infection from one patient to another if the bronchoscope is disinfected inadequately, or, isolation of microorganisms from bronchoscopic specimens in a patient who is clinically not infected, i.e., pseudo-infection. This study is one such investigation of an outbreak of bronchoscopic pseudo-infections in a tertiary care hospital.

Materials and methods: Bronchoalveolar lavage (BAL) samples were inoculated onto MacConkey Agar and 5% Sheep Blood Agar and incubated at 37 °C overnight. The growths obtained on culture media were processed for identification and antimicrobial susceptibility on Vitek 2 Compact as per manufacturer’s instructions. To investigate the outbreak, 5 mL - 10 mL of sterile water was flushed through the channels of disinfected bronchoscope and collected in a sterile container. The samples were centrifuged and inoculated onto MacConkey Agar and 5% Sheep Blood Agar. The growths obtained were further processed similarly as the BAL samples were processed. Environmental swabs collected from the bronchoscopy unit were also processed as the procedure mentioned above.

Results: Bronchoalveolar lavage of 3 patients in a period of 1 week were contaminated with multidrug resistant Klebsiella pneumoniae. Two out of five bronchoscope fluid samples were also contaminated with Klebsiella pneumoniae. Among the swabs collected from bronchoscope unit, Klebsiella pneumoniae was isolated from the detergent box of the endowasher.

Conclusion: The risk of propagation of infection via a bronchoscope can be evaded by proper reprocessing and improving the sterilization practices.