Antimicrobial resistance profile and prevalence of extended-spectrum beta-lactamases (ESBL), AmpC beta-lactamases and colistin resistance (mcr) genes in Escherichia coli from swine between 1999 and 2018
Antimicrobial resistance profile and prevalence of extended-spectrum beta-lactamases (ESBL), AmpC beta-lactamases and colistin resistance (mcr) genes in Escherichia coli from swine between 1999 and 2018
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DOI：
10.1186/s40813-020-00146-2
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发表时间：
2020-04-02
影响因子：
3.4
通讯作者：
Martin, Marga
中科院分区：
文献类型：
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作者：
Aguirre, Laia;Vidal, Anna;Martin, Marga
抗生素在牲畜中的频繁使用导致了耐药性细菌在动物及其产品中的传播，全球公共卫生和兽医都在警告要监测这种耐药性。本研究旨在确定过去20年西班牙养猪场的抗生素耐药性模式和基因。通过定性（纸片扩散）和定量（最小抑菌浓度，MIC）方法，检测了1999年至2018年期间从新生仔猪和断奶后仔猪腹泻临床病例中分离的200株大肠杆菌对养猪生产中常用的6种抗生素的敏感性。结果显示，自1999年以来，阿莫西林和四环素的耐药率约为100%，在整个研究期间，头孢噻呋耐药率逐渐增加。对于粘菌素，在2011 - 2014年期间检测到耐药高峰（17.5%的菌株）。关于庆大霉素，纸片扩散法测定的30株中度敏感菌株中，有11株通过MIC测定呈耐药。此外，最常见的耐药基因是超广谱β-内酰胺酶（ESBL）bla（CTX M）（13.5%的菌株，最常见的基因组为CTX-M-14、CTX-M-1和CTX-M-32，其次为CTX-M-27、CTX-M-9和CTX-M-3）、AmpC型β-内酰胺酶（AmpC）bla（CMY-2）（3%）和粘菌素耐药基因mcr-4（13%），mcr-1（7%）和比例较小的mcr-5（3%）。有趣的是，这些mcr基因早在2000年就已经在分离出的菌株中被检测到了，比它们首次被描述的时间早了十多年。然而，在本研究中发现基因型mcr特征与MIC表型检测之间的一致性较差。这些结果表明，尽管是当前关注的问题，但抗性基因和因此的抗微生物剂抗性表型在世纪初就已经存在于养猪场中。
The frequent usage of antibiotics in livestock has led to the spread of resistant bacteria within animals and their products, with a global warning in public health and veterinarians to monitor such resistances. This study aimed to determine antibiotic resistance patterns and genes in pig farms from Spain during the last twenty years. Susceptibility to six antibiotics commonly used in pig production was tested by qualitative (disk diffusion) and quantitative (minimum inhibitory concentration, MIC) methods in 200 strains of Escherichia coli which had been isolated between 1999 and 2018 from clinical cases of diarrhoea in neonatal and post-weaned piglets. Results showed resistance around 100% for amoxicillin and tetracycline since 1999, and a progressive increase in ceftiofur resistance throughout the studied period. For colistin, it was detected a resistance peak (17.5% of the strains) in the 2011-2014 period. Concerning gentamicin, 11 of 30 strains with intermediate susceptibility by the disk diffusion method were resistant by MIC. Besides, the most frequent antimicrobial resistance genes were the extended-spectrum beta-lactamase (ESBL) bla(CTX-M) (13.5% of strains, being CTX-M-14, CTX-M-1 and CTX-M-32 the most prevalent genomes, followed by CTX-M-27, CTX-M-9 and CTX-M-3), AmpC-type beta-lactamase (AmpC) bla(CMY-2) (3%) and colistin resistance genes mcr-4 (13%), mcr-1 (7%) and in less proportion mcr-5 (3%). Interestingly, these mcr genes were already detected in strains isolated in 2000, more than a decade before their first description. However, poor concordance between the genotypic mcr profile and the phenotypical testing by MIC was found in this study. These results indicate that although being a current concern, resistance genes and therefore antimicrobial resistant phenotypes were already present in pig farms at the beginning of the century.