Department of Microbiology, Faculty of Basic Sciences, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran.
Department of Microbiology, Faculty of Basic Sciences, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran.
Acta Trop. 2022 Aug;232:106485. doi: 10.1016/j.actatropica.2022.106485. Epub 2022 Apr 26.
The prevalence of multidrug-resistant Enterobacter aerogenes strains in UTIs is increasing. Therefore, the purpose of this study was to examine the mechanisms of resistance in Enterobacter aerogenes strains isolated from the urinary tract of infected patients. To achieve this goal, 786 urine samples from Shahrekord, Iran, were collected from June 2019 to February 2020. After isolating and identifying E. aerogenes samples, antibiotic susceptibility testing was done on the strains using Kirby-Bauer's disk diffusion method. The biofilm formation assays were performed to study the link between antibiotic resistance and biofilm formation and virulence genes. As a result, amongst the 786 urine samples, 50 strains were identified as E. aerogenes. The lowest rate of resistance was observed with imipenem (30%). This study also reports that all the strains of E. aerogenes are biofilm producers, with 50% of isolates producing a large amount, 30% a moderate amount, and 20% a small amount of biofilm. 42% were identified in the phenotypic study of ESBLs. In the PCR test, (64%) produced broad-spectrum beta-lactamases. Prevalence of qnrC, qnrB, qnrA, tetA, tet B, acc(3)IIa, acc(2)IIa, ant(2)Ia and Sul1 in strong producing isolates reported 100%, 80.95%,% 58.14, 87.5%, 81.58%, 86.67%, 82.14, 81.48% and 90% respectively. In the statistical analysis based on the chi-square test, a statistically significant relationship was reported between qnrA, qnrB, tetA, tetB, Sul1, ant(2)Ia, ant(3)I, aac(3)II, and biofilm formation. Resistance to cephalothin, ceftriaxone, cefotaxime and ceftazidime were reported 40%, 34%, 30% and 30%, respectively. Out of 50 Enterobacter aerogenes, 32 isolates (64%) were identified in the phenotypic study of ESBLS, prevalence of bla, bla and bla reported 30%, 20% and 14% respectively. There is a significant relationship between resistance to ceftriaxone and bla Prevalence of csgA, ybtS, markD, rmpA, csgD and fimH in strong biofilm formation isolates reported 84%, 83.33%, 80%, 80%, 80% and 66% respectively. The chi-square test showed a statistically significant relationship between biofilm production and resistance genes fimH, csgA, csgD, ybtS, and mrkD. The findings of this study indicate that the ability to produce biofilms is associated with the increase of antibiotic resistance and virulence genes. These agents enable bacteria to produce biofilms that ultimately lead to colonization and bacterial survival in the body.
产酸克雷伯菌在尿路感染中的多药耐药株的流行率正在上升。因此，本研究的目的是研究从感染患者的泌尿道分离的产酸克雷伯菌菌株的耐药机制。为了实现这一目标，从 2019 年 6 月至 2020 年 2 月，从伊朗设拉子采集了 786 份尿液样本。在分离和鉴定产酸克雷伯菌样本后，使用 Kirby-Bauer 圆盘扩散法对菌株进行抗生素药敏试验。进行生物膜形成测定以研究抗生素耐药性与生物膜形成和毒力基因之间的联系。结果，在 786 份尿液样本中，有 50 株被鉴定为产酸克雷伯菌。对亚胺培南的最低耐药率为 30%。本研究还报告说，所有产酸克雷伯菌菌株都是生物膜生产者，其中 50%的分离株产生大量生物膜，30%的分离株产生中等量生物膜，20%的分离株产生少量生物膜。在表型研究中，42%的分离株被鉴定为 ESBLs。在 PCR 试验中，(64%)产生广谱β-内酰胺酶。qnrC、qnrB、qnrA、tetA、tetB、acc(3)IIa、acc(2)IIa、ant(2)Ia 和 Sul1 在强产生分离株中的检出率分别为 100%、80.95%、58.14%、87.5%、81.58%、86.67%、82.14%、81.48%和 90%。在基于卡方检验的统计分析中，报告了 qnrA、qnrB、tetA、tetB、Sul1、ant(2)Ia、ant(3)I、aac(3)II 和生物膜形成之间存在统计学显著关系。对头孢噻肟、头孢曲松、头孢噻肟和头孢他啶的耐药率分别为 40%、34%、30%和 30%。在 50 株产酸克雷伯菌中，32 株（64%）在 ESBLS 的表型研究中被鉴定为阳性，bla、bla 和 bla 的检出率分别为 30%、20%和 14%。头孢曲松耐药性与 bla 之间存在显著关系。在强生物膜形成分离株中，csgA、ybtS、markD、rmpA、csgD 和 fimH 的检出率分别为 84%、83.33%、80%、80%、80%和 66%。卡方检验显示生物膜形成与耐药基因 fimH、csgA、csgD、ybtS 和 mrkD 之间存在统计学显著关系。本研究的结果表明，生物膜形成能力与抗生素耐药性和毒力基因的增加有关。这些因子使细菌能够产生生物膜，最终导致细菌在体内定植和存活。
