Prevalence of Class 1 and Class 2 Integrons in Extensively Drug-Resistant Escherichia Coliisolated from Iraqi Patients with Diabetic Foot Ulcers in Diyala Province

Abstract

Diabetic foot infectionis a common and serious problem for all health systems in the world. This study aimed tomolecularlydetect class (1)and class (2) integron genes responsible for antibiotic resistance by using PCR techniquein extensively drug-resistant Escherichia colibacteria isolated from clinical samples of (285) Iraqi patients with diabetic foot ulcers(DFUs) who attended different hospitals in Diyala province/Iraq during the period from July to the end of October /2020. The results showed that bacterial isolates appeared in (250) of these samples. The conventional microbiological methods and VITEK 2 automated system showed that 65 (26%) of the isolates were Escherichia coli isolates.For all the (65) pathogenic isolates of Escherichia coli, susceptibility testswere performed against 15antimicrobial agents.The results of antibiotic resistance showedthe following:Amoxicillin-Clavulanic acid 100%, cefotaxime 92.3%, piperacillin 84.%, ceftriaxone 78.4%, cefepime 76.6%,ceftazidime75.3%, ciprofloxacin 67.9%, levofloxacin 69.2%,while resistance rate to aminoglycosides was 92.3, 80% and 76.9% for gentamicin, amikacin and tobramycin respectively. Resistance rate foraztreonam was 52.3%, Imipenem 33.8% and Meropenem 43%.However, 20 (30.7%) isolatesof Escherichia coli were found to be extensively drug-resistant. Depending on the detection of integrase gene for the investigation of class 1 and class 2 integrons, PCR assay showed that 16(80%) of the extensively drug-resistant E. coli isolates were integrase gene positive, which confirms the extremely high dissemination of class 1 integron at the hospitals of Baquba city in Diyala province, while class2 integrase gene was not found. Analysis of class 1 integron variable regions showed the presence of (5) different fragment sizes of approximately 500, 600,700, 800 and 900 bp. On RFLP using restriction enzyme AluI, five different restriction patterns obtained Class1(500bp, 200-300 fragment), Class2 (±600bp, 90-200-300 fragment) Class3 (700bp, 200-500 fragment), Class4 (800bp, 100-200-500 fragment) and Class5(900bp, 100,200,600 fragment).