The Relationship of Class I Integron Gene Cassettes and the Multidrug-Resistance in Extended -Spectrum β-Lactamase Producing Isolates of Escherichia coli

Abstract

Background: Integron is an important element in creating multi-drug resistant (MDR) bacteria. This study evaluated the relationship of class I integron and antibiotic resistance in extended-spectrum beta-lactamase producing (ESBL) isolates of Escherichia coli (E. coli). Methods: A total of 66 ESBL-producing E. coli were isolated from urinary tract infection in Kermanshah and their antimicrobial susceptibility was assessed. The incidence of class I integron was determined in isolates using PCR. The class I integron-associated gene cassettes were also verified by DNA sequencing. Data were analyzed using statistical methods. Results: Of 66 ESBL-producing isolates, 65 (98.5%) were MDR. The most prevalent antibiotic resistance of the isolates was observed for ampicillin (98.4%), ceftriaxone (98.4%), cefotaxime (95.4%), and co-trimoxazole (86.3%). The frequency of class I integron in isolates was 92.3%. The relationship between class I integron and resistance to streptomycin, co-trimoxazole, and ceftazidime was statistically significant. The genes encoding resistance to streptomycin and co-trimoxazole, as well as a gene encoding a protein with unknown function, were associated with class I integron. The most common gene cassette was dfrA17-aadA5. Conclusions: The results indicate a high prevalence of antibiotic resistance among ESBL-producing isolates to the antibiotics commonly used for the empirical treatment of urinary tract infections. The frequency of class I integron and associated gene cassettes involving resistance to antibiotics is high. There is a high percentage of MDR among the ESBL-producing isolates, which mostly contain gene cassettes. These findings suggest a strong association of integron and ESBL genes in the isolates.

The Relation between Class I Integrons and Multidrug-Resistance in Extended-Spectrum Beta Lactamase Producing Escherichia coli Isolates.

“…The spread of mobile genetic elements among different strains may have resulted in the antimicrobialresistant phenotypes observed in this study. Akya et al in Iran found that the highest rate of resistance was noticed for ceftriaxone, cefotaxime, and cotrimoxazole [23] which agrees with a previous study in Iran [24]. A higher percentage of MDR (87.9%) among E. coli isolates was reported by Al-Hammadi and colleagues in Yemen [25].…”

“…It was found that 88.5%, 83.6%, 83.6% and 81.9% out of 61 MDR ESBL producing E. coli isolates that harbored class I integrons were significantly resistant to aztreonam, ceftazidime, cefotaxime and ciprofloxacin, respectively (p<0.05). Similarly, Akya et al observed a significant correlation between antibiotic resistance to co-trimoxazole (P = 0.01), streptomycin (P= 0.018) and ceftazidime (P=0.032) with class I integrons, which emphasizes the association between resistant genes and this class of integron [23].…”

“…Furthermore, 84.7 % out of ESBL-producing isolates were MDR. Akya et al found that 27.5 % of isolated E. coli strains from UTIs were ESBLproducers and among them, 98.5% were MDR [23]. Moreover, El-Hendawy et al in Egypt demonstrated that ESBL genes were positive among 24 out of 32 E. coli isolates studied (75%) and all of them were MDR [26].…”

“…On the other hand, other studies have shown that class 1 integron values were nearly closer to the value of class 1 integrons in our study. For example, Akya et al found that class I integron was detected in 92.3% of MDR ESBLproducing E. coli isolates and among them, 57 isolates harbored gene cassettes of different sizes [23]. Also, Pérez-Etayo et al demonstrated that class 1 integron was present in 92% of the ESBLproducing E. coli isolates [22].…”

Detection of classⅠintegrons with phenotypic ESBL detection among enterobacteriaceae isolated from patients with urinary tract infection in Sulaimani provenance/ Iraq

“…42 About 9% of the sequenced bacterial genomes contain integrons, and the class I integron platform is the most prevalent one and had received the most reports among clinical bacteria, and is still the subject of several investigations. 43 The prevalence rate of class I integron in this study was 54.2%, there are many studies all over the world that record different prevalence rates of integron classes specifically class I integron among Enterobacteriaceae [44][45][46][47][48] this variation might be due to difference in the sample population, geographical distribution, and groups which had been selected for taking urine samples.…”