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Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
Published on: March 3, 2023
Microorganisms' colonization and their antibiotic resistance pattern in oro - tracheal tube
Alireza Abdollahi1, Saeed Shoar, Nasrin Shoar
1Division of Pathology, Imam Khomeini Hospital, Tehran University of Medical Sciences Tehran, Iran.
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 (pipracillintazobactam 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.
Insights
Acinetobacter was the most common colonizer in intubated patients, showing resistance to ciprofloxacin. Imipenem and piperacillin-tazobactam demonstrated broad sensitivity, guiding empirical antibiotic therapy for nosocomial infections.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Critical Care Medicine
Background:
- Nosocomial infections are a critical issue in intubated patients, contributing to significant morbidity and mortality.
- Understanding microbiological colonization and antibiotic resistance patterns is crucial for effective management.
Purpose of the Study:
- To investigate microorganism colonization and antibiotic resistance patterns in patients with endotracheal tubes or tracheostomies.
- To inform empirical antibiotic therapy strategies in this patient population.
Main Methods:
- A cross-sectional study involving 880 intubated or tracheostomized patients.
- Microbiological cultures and antibiograms were obtained from samples after extubation.
- Data collected between 2008 and 2011 at Imam Khomeini hospital.
Main Results:
- Acinetobacter (24.2%) was the most frequently isolated organism, followed by Pseudomonas aeruginosa (16.7%) and Staphylococcus aureus (12%).
- Significant antibiotic resistance was observed in Acinetobacter (ciprofloxacin, ceftazidime, cefepime), S. aureus (imipenem), and Klebsiella (piperacillin-tazobactam).
- Ciprofloxacin showed the highest resistance prevalence.
Conclusions:
- Acinetobacter is the predominant colonizer of endotracheal tubes in hospitalized patients.
- Empirical antibiotic treatment can potentially be initiated before culture results are available.
- Imipenem and piperacillin-tazobactam exhibited broad sensitivity against the isolated microorganisms.
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