رسائل ماجيستير
English
2023
Study the Role of Carbonyl Cyanide 3-Chlorophenyl- hydrazine as efflux pump inhibitor among Enterobacteriaceae isolates in Babylon, Iraq
علاء هاني الجرّاخ, هديل قاسم جبر ادريس العيساوي
كلية الطب-جامعة بابل · العراق
Multidrug-resistant (MDR) Enterobacteriaceae are an emerging and major concern for the medical community. Reported rates of multidrug-resistant Enterobacteriaceae are increasing, and infections with these organisms are no longer limited to those associated with healthcare in the severely ill or infirm. Community-acquired infections are now described.
The purpose of this study was to investigate the role of active efflux systems in aminoglycoside and quinolone resistance in clinical isolates of Enterobacteriaceae using the efflux pump inhibitor CCCP. A total of 300 different clinical samples were collected from patients (females 172: 57.3%; males 128: 42.6%) with urinary tract infection (urine), reproductive system infection (swabs), bacteremia (blood), and lower respiratory tract infection (sputum) in Al-Mahaweel General Hospital, Marjan Teaching Hospital, and private laboratories during the period from November 2022 to March 2023.
The results showed that out of 300 samples, 280 (93%) were culture-positive, and 20 (6.6%) were culture-negative clinical samples. Out of 280 culture-positive samples, 134 (47.85%) belonged to Enterobacteriaceae, while the remaining 146 (52.14%) samples belonged to other types of bacteria.
After observing the cultural and morphological characteristics of the bacterial isolates, the following were identified: E. coli n=94 isolates, Klebsiella pneumoniae n=24, Proteus spp n=7, and Enterobacter spp n=9. The identification of all Enterobacteriaceae isolates was confirmed by the Vitek-2 automated identification system.
The distribution of E. coli isolates was as follows: urinary tract infections (UTIs) 43 isolates, lower respiratory tract infections (LRTIs) 20 isolates, bacteremia 17 isolates, and bacterial vaginitis 14 isolates. K. pneumoniae 24 isolates were distributed as UTIs 4 isolates, RTIs 8 isolates, and bacteremia 12 isolates. Enterobacter spp 9 isolates: UTIs 7 isolates, bacteremia 2 isolates. Proteus spp 7 isolates: UTIs 6 isolates, bacteremia 1 isolate.
Regarding age groups and gender, infections with E. coli and K. pneumoniae were higher among females than males. In contrast, infections with Enterobacter spp and Proteus spp were higher among males than females.
The antibiotic susceptibility testing (AST) of all Enterobacteriaceae isolates was performed using the Vitek-2 system and disk diffusion test with 8 antibiotics. The results showed that in general, all Enterobacteriaceae isolates were more resistant to fluoroquinolones than aminoglycosides.
The antibiotic resistance patterns (ARP) of Enterobacteriaceae isolates were determined based on Vitek-2 system results (Index-1). Out of 134 isolates, 61 were sensitive, and 73 showed different resistance patterns: 48 were multidrug-resistant (MDR), 17 were extensively drug-resistant (XDR), and 8 were pandrug-resistant (PDR).
In this study, oqxAB genes were detected in selected clinical isolates of MDR, XDR, and PDR Enterobacteriaceae. The selected isolates were: 12 XDR E. coli, 1 PDR K. pneumoniae, and 1 MDR Enterobacter spp. PCR results showed that 6 (42.8%) out of 14 isolates were positive for the oqxA gene, while 8 (57.1%) were negative. No isolates showed positive results for the oqxB gene.
To confirm the effective role of the efflux pump, the MICs of three antibiotics were compared with and without the efflux pump inhibitor (CCCP). The MIC results for the 14 Enterobacteriaceae isolates showed that all isolates had MIC ≥128 μg/mL in the absence of CCCP for levofloxacin, ciprofloxacin, and gentamycin. In the presence of CCCP, the MIC of levofloxacin and ciprofloxacin decreased, and bacterial growth was inhibited. However, all isolates showed high MIC values (≥128 μg/mL) for gentamycin even with CCCP, indicating no effect of the inhibitor in reducing the MIC for gentamycin.