Bahramian Aghil, Eslami Gita, Hashemi Ali, Tabibi Ali, Heidary Mohsen
1 Urology and Nephrology Research Center, Shahid Labbafinejad Hospital, Shahid Beheshti University of Medical Sciences , Tehran, Iran.
2 Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences , Tehran, Iran.
Acta Microbiol Immunol Hung. 2018 Mar 1;65(1):15-25. doi: 10.1556/030.64.2017.030. Epub 2017 Nov 15.
Urinary tract infection (UTI) is a common type of infectious disease globally. The aim of this study was to detect the frequency of fosA3 and fosC2 genes in extended-spectrum β-lactamases (ESBL) and bla, bla, and bla genes in AmpC β-lactamases-producing isolates of Escherichia coli. In total, 120 isolates of E. coli were collected from three teaching hospitals between March 2014 and February 2015. Antibiotic susceptibility tests were carried out by disk diffusion method. The presence of bla, bla, bla, fosA3, and fosC2 genes was detected by polymerase chain reaction (PCR) and sequencing. Of the 120 strains, 92 (76.6%) were identified as ESBL producers, 30 (25%) were determined as AmpC β-lactamase producers, and 24 (20%) had both ESBL and AmpC β-lactamase enzymes. Imipenem, fosfomycin, and nitrofurantoin had the best effect against isolates of E. coli. PCR assay demonstrated that the frequency of bla, bla, and bla genes among AmpC β-lactamases-producing strains were 39%, 1%, and 17.5%, respectively. This study reports the first detection of fosfomycin resistance in Iran. This study indicated the increasing prevalence of UTI isolates of E. coli-harboring ESBL and AmpC β-lactamases genes in Iran. Therefore, due to the high rate of bla and bla genes and emergence of fosfomycin-resistant E. coli isolates, we recommend continuous monitoring of antibiotic resistance as well as attention to guidelines of infection controls.
尿路感染（UTI）是全球常见的一种传染病类型。本研究的目的是检测产超广谱β-内酰胺酶（ESBL）的大肠杆菌分离株中fosA3和fosC2基因的频率，以及产AmpCβ-内酰胺酶分离株中bla、bla和bla基因的频率。2014年3月至2015年2月期间，从三家教学医院共收集了120株大肠杆菌分离株。采用纸片扩散法进行药敏试验。通过聚合酶链反应（PCR）和测序检测bla、bla、bla、fosA3和fosC2基因的存在情况。在120株菌株中，92株（76.6%）被鉴定为产ESBL菌株，30株（25%）被确定为产AmpCβ-内酰胺酶菌株，24株（20%）同时具有ESBL和AmpCβ-内酰胺酶。亚胺培南、磷霉素和呋喃妥因对大肠杆菌分离株的效果最佳。PCR检测显示，产AmpCβ-内酰胺酶菌株中bla、bla和bla基因的频率分别为39%、1%和17.5%。本研究首次报道了伊朗磷霉素耐药情况。该研究表明，伊朗携带ESBL和AmpCβ-内酰胺酶基因的大肠杆菌UTI分离株的患病率在增加。因此，鉴于bla和bla基因的高发生率以及耐磷霉素大肠杆菌分离株的出现，我们建议持续监测抗生素耐药性，并关注感染控制指南。
