Microbial colonization of endotracheal tube in intensive care unit patients

Abstract

Microbial biofilms has remained a major complication of tracheal intubation in patients requiring ventilator equipment. The aim of this study was to characterize bacterial and fungal biofilms in endotracheal tubes from intensive care unit (ICU) patients in Ahwaz, Iran. In this cross-sectional descriptive study, patients admitted to ICU that required mechanical ventilation for at least 24 hours were evaluated. Specimens were collected from tracheal tubes of patients with endotracheal aspiration, when they had clinical manifestation of pneumonia. The specimens were microbiologically investigated and the bacterial and fungal isolates were identified by using standard cultural and biochemical tests. In total, 350 cases had tracheal tube aspirate positive cultures. The most of isolates are known to cause colonization of endotracheal tube included: Coagulase negative staphylococci(18.2%), E.coli (18%), Enterobacter spp. (16.2%), Pseudomonas spp. (14.6%), Acinetobacter spp. (9.7%), S.aurous (8.1%), Klebsiella spp. (6.7%), and Serratia spp. (0.4%). 7.4% were colonized with Candida spp. that the most common species was C.albicans (42.3%). The coagulase negative staphylococci species identified by mass spectrometry were: S.epidermidis (64%), S.haemolyticus (17.1%), S.lugdune (3.1%), S.warnerii (6.25%), S.hominis (6.25%), S.pasteur (3.1%). There was significant association between duration of being intubated and S.aurous, Enterobacter spp. (P=0.002). The presence of bacterial and fungal biofilms of endotracheal tube suggests that it may be important in biofilm development and may provide a therapeutic target for the prevention of ventilator-associated pneumonia.