Tehran University of Medical Sciences Iranian Journal of Microbiology 2008-3289 5 2 2013 06 15 102 107 EN Alireza Abdollahi Division of Pathology, Imam Khomeini Hospital, Tehran University of Medical Sciences Tehran, Iran. Saeed Shoar Department of Surgery, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran. Nasrin Shoar School of Medicine, Kashan University of Medical Sciences, Kashan, Iran. 2015 10 16 Background and Objectives: Recently, nosocomial infections have been discussed as a critical issue among intubated patients leading to significant morbidity and mortality. Hence, the pattern of microbiological colonization and antibiotic resistance are much valuable in this regard. We aimed to investigate the pattern of microorganism colonization and antibiotic resistance in patients with endotracheal tube or tracheostomy to propose a proper empirical antibiotic therapy in this setting. Materials and Methods: This cross sectional study was conducted among 880 patients admitted in Imam Khomeini hospital between 2008 and 2011 who were subsequently intubated or underwent tracheostomy due to insufficient self ventilation. Samples for microbiological cultures were obtained after extubation and then sent to the central laboratory for further assessment. Antibiograms and microbiological cultures were obtained for each sample. Results: Of 880 patients enrolled in this study, 531 (60.3%) were male and 349 (39.7%) were female. Nineteen different organisms were isolated including Acinetobacter (213, 24.2%), Pseudomonas aeruginosa (147, 16.7%), Staphylococcus aureus (106, 12%), Proteus mirabilis (90, 10.2%), and other organisms (324, 36.8%). Antibiotic resistance was mainly seen in Acinetobacter (ciprofloxacin, ceftazidim, cefepim, and penicillin), S. aureus (imipenem) and Klebsiella (pipracillin- tazobactam and ampicillin-sulbactam). Conclusion: This study represents the most common microorganisms colonizing tracheal tube of hospitalized patients and their pattern of antibiotic resistance. Acinetobacter was the most common microorganism isolated from endotracheal tube. Hence, it may be possible to initiate the empiric antibiotic treatment before the results of culture are become available. Ciprofloxacin was also the most prevalent antibiotic revealing resistant pattern. Moreover, most of the microorganisms were sensitive to imipenem and pipracillin-tazobactam. https://ijm.tums.ac.ir/index.php/ijm/article/view/630 https://ijm.tums.ac.ir/index.php/ijm/article/download/630/403