رسائل ماجيستير
English
2024
Antibiotic Resistance Patterns and Molecular Typing of Acinetobacterbaumannii Clinical Isolates and Hospital Environment at Alia Governmental Hospital, Palestine
حاتم خالد عيدة, دينا محمد مصباح خضيرات
كلية المهن الصحية - العلوم الطبية المساندة-جامعة القدس · فلسطين
In recent years, Acinetobacter baumannii has received increasing attention due to its capability of acquiring multi-resistance to antibiotics and its potential to cause disease in humans. It is also known for its intrinsic antimicrobial resistance mechanisms. Several studies documented the increase in the percentage of resistance to antimicrobial agents in four major antimicrobial classes: fluoroquinolones, aminoglycosides, β-lactams including carbapenems. The increase in carbapenem resistance is of particular concern, as this class of antibiotics is usually considered the last choice in treating resistant A. baumannii.
This opportunistic pathogen is able to survive in the environment under unfavorable conditions for prolonged periods, which contributes to its increased virulence. Thus, the hospital environment may serve as a reservoir for resistant A. baumannii strains, allowing easy spread in hospitals and serving as a source of nosocomial infections in patients, healthcare personnel, and visitors.
Aims: This study aimed at the characterization of A. baumannii isolates from inpatients and hospital environments, to determine their antimicrobial resistance pattern, detect carbapenem-resistant A. baumannii (CRAB), and investigate genetic relatedness between isolates using the random amplification of polymorphic DNA (RAPD) typing technique.
Methodology: In this study, a total of 24 clinical isolates were obtained from various clinical specimens such as wounds, blood, urine, eswabs, and sputum during the period April 1, 2023, to December 31, 2023, from Alia Governmental Hospital, Hebron, Palestine. The Vitek2 system was used for identification and antibiotic susceptibility testing. Concurrently, a total of 126 specimens were collected from different environments of the hospital and identified as A. baumannii using conventional identification methods and CHROMagar Acinetobacter selective medium. The isolates were tested for antibiotic susceptibility using the disk diffusion method.
All isolates (both clinical and environmental) were tested for the presence of the blaOXA-51 gene using PCR. Finally, the genetic relatedness between isolates was determined using the RAPD typing technique.
Results: Twenty-four clinical isolates and 29 environmental isolates were identified as A. baumannii. All isolates were confirmed by detecting the blaOXA-51-like gene. Among the environmental isolates, patients’ beds were the most contaminated site (20.6%, 6/29), while the largest number of clinical isolates was obtained from wounds (10 isolates: 41.7%). The majority of clinical and environmental isolates were collected from the intensive care unit (ICU).
Multidrug-resistant A. baumannii (MDRAB) was detected in approximately 74% of clinical isolates and in 100% of environmental isolates. Co-trimoxazole (COT) was the most effective antibiotic against both clinical and environmental A. baumannii isolates. For other antibiotics, clinical and environmental isolates showed high resistance rates: 86.2% and 96.6% of environmental isolates were resistant to imipenem (IM) and meropenem (MEM), respectively, while clinical isolates had resistance rates of 72.7% and 77.3% to IM and MEM, respectively.
Using the RAPD-PCR typing technique, four clusters (A–D) grouped more than one isolate, while the remaining isolates each had unique patterns. Some RAPD clusters included both environmental and clinical isolates.
Conclusion and Recommendations: This study clearly suggests that the rate of MDRAB and CRAB is increasing and is an important cause of nosocomial infections. The genetic relatedness between clinical and environmental isolates and the detection of high rates of antimicrobial-resistant A. baumannii in various hospital environments suggest the potential role of the hospital environment, through various clinical activities, in the cross-contamination of A. baumannii infections, particularly in the ICU.
These findings highlight the importance of identifying A. baumannii infections early and implementing strict infection control strategies. It is recommended that hospital wards be vigorously sanitized and disinfected periodically.