Antimicrobial Resistance Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Microbiology and Virology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
Department of Veterinary Medicine, Tehran University of Veterinary Science, Tehran, Iran.
Microb Pathog. 2020 Feb;139:103850. doi: 10.1016/j.micpath.2019.103850. Epub 2019 Nov 6.
Efflux of antibiotics is an effective resistance mechanism among antibiotic-resistant Staphylococcus aureus. This systematic review aims to evaluate the frequency and expression of efflux pump genes in S.aureus around the world.
A comprehensive literature search of several databases (Medline Pub Med, ISI, Scopus, Google Scholar, ISC, Science direct and Persian Journals Online, and citation lists) was performed. We considered published studies from 2001 to 2018. Articles reporting the prevalence and expression of efflux pump genes were selected.
Among 183 articles, 36 studies were selected. Of the 36, 23 articles were conducted in Asia.6 in Europe, 5 in America and 2 in African countries. In most of these studies norA, norB, qacA/B genes were commonly evaluated by molecular methods. The presence of efflux pump genes such as norA, norB, norC, mepA, mdeA, qacA/B was detected by PCR in 21 studies and over-expression of genes were reported in 13 studies. The most frequently reported genes in Asia were norA (75%), norB (60%), mepA (35%), mdeA (33%) and qacA/B (20.8%). In European studies, the prevalence of norB was mostly reported among S.aureus isolates and norA and qacA/B were commonly found in similar studies in America. The investigation of gene expression patterns showed that norA was most frequent single-pattern in Asia and America, norB or mdeA in Europe.
According to this study MDR efflux pumps not only cause high-level resistance but also it considerably associated with over-expression of these genes. Due to the selective pressure on MRSA isolate, the enormous diversity of plasmid-encoded genes had been recorded in different regions, owing to the various numbers and types of isolates in each study or types of disinfectants for general use.
抗生素外排是抗生素耐药金黄色葡萄球菌（antibiotic-resistant Staphylococcus aureus）中一种有效的耐药机制。本系统评价旨在评估全球范围内金黄色葡萄球菌中外排泵基因的频率和表达。
对多个数据库（Medline Pub Med、ISI、Scopus、Google Scholar、ISC、Science direct 和 Persian Journals Online 以及引文列表）进行了全面的文献检索。我们考虑了 2001 年至 2018 年期间发表的研究。选择了报告外排泵基因的流行率和表达的文章。
在 183 篇文章中，有 36 篇被选中。在这 36 篇文章中，有 23 篇是在亚洲进行的。欧洲有 6 篇，美洲有 5 篇，非洲国家有 2 篇。在这些研究中，大多数通过分子方法评估了 norA、norB、qacA/B 基因。通过 PCR 检测到 21 项研究中存在 norA、norB、norC、mepA、mdeA、qacA/B 等外排泵基因，13 项研究报告了基因的过度表达。在亚洲报道的最常见基因是 norA（75%）、norB（60%）、mepA（35%）、mdeA（33%）和 qacA/B（20.8%）。在欧洲研究中，norB 是金黄色葡萄球菌分离株中最常见的耐药基因，而 norA 和 qacA/B 则是美洲类似研究中常见的耐药基因。基因表达模式的调查显示，norA 是亚洲和美洲最常见的单基因模式，而 norB 或 mdeA 则是欧洲的常见模式。
根据这项研究，多药耐药外排泵不仅导致高水平耐药，而且与这些基因的过度表达密切相关。由于对耐甲氧西林金黄色葡萄球菌（MRSA）分离株的选择性压力，不同地区记录了大量质粒编码基因的多样性，这是由于每个研究中的分离株数量和类型或常用消毒剂类型的不同。
