Screening for ESBL-KP in fecal samples was performed by selective cultivation. The bacterial species were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rDNA sequence analysis. Minimum inhibitory concentrations (MICs) of 16 antibiotics were determined by the agar dilution method. Plasmid replicons, antimicrobial resistance genes and Sequence types (STs) of the isolates were determined by whole-genome sequencing (WGS). Genetic relatedness of ESBL-KP isolates was determined by the single nucleotide polymorphisms (SNP). The S1 nuclease-pulsed-field gel electrophoresis (S1-PFGE) was used to characterize the plasmids carried by ESBL-KP isolates. Conjugation assays was used to verify the transferability of bla CTX - M.
ESBL-KP prevalence rates increased from 12.0% in 2015 to 27.5% in 2017. The experimental results showed that 97% of isolates had multi-drug resistance. Multiple ESBL resistance genotypes were commonly detected in the isolates. STs among the ESBL-KP isolates were diverse. All 69 bla CTX-M-3-positive isolates were located on plasmids, and these genes could be transferred with plasmids between different strains. Phylogenetic analysis showed the possibility of transmission among some isolates.
This study obtained the drug resistance patterns, the drug resistance phenotype and molecular characteristics of fecal-derived ESBL-KP in rural communities in Shandong Province, China. We report a rapid increase in occurrence of ESBL-KP among fecal samples collected from healthy rural residents of Shandong Province from 2015 to 2017. The carriage rate of multidrug-resistant bacteria in healthy residents is increasing. Thus, a need for further monitoring and possible interventions of ESBL-KP in this region is warranted.
未经鉴定:通过选择性培养进行粪便样品中ESBL-KP的筛选。使用基质辅助激光解吸/电离飞行时间质谱(MALDI-TOFMS)和16SrDNA序列分析鉴定细菌物种。通过琼脂稀释法测定16种抗生素的最小抑制浓度(MIC)。质粒复制子,通过全基因组测序(WGS)确定分离株的抗菌素抗性基因和序列类型(STs)。ESBL-KP分离株的遗传相关性由单核苷酸多态性(SNP)确定。S1核酸酶脉冲场凝胶电泳(S1-PFGE)用于表征ESBL-KP分离株携带的质粒。缀合测定用于验证blaCTX-M的可转移性。
UNASSIGNED:ESBL-KP患病率从2015年的12.0%增加到2017年的27.5%。实验结果表明,97%的分离株具有多重耐药性。在分离物中通常检测到多种ESBL抗性基因型。ESBL-KP分离株中的STs是多样的。所有69个blaCTX-M-3阳性分离株都位于质粒上,这些基因可以通过质粒在不同菌株之间转移。系统发育分析表明在某些分离株之间传播的可能性。
未经批准:本研究获得了耐药模式,山东省农村粪便来源ESBL-KP耐药表型及分子特征,中国。我们报告了2015年至2017年山东省健康农村居民粪便样本中ESBL-KP的发生率快速增长。健康居民多重耐药菌的携带率不断提高。因此,有必要在该地区进一步监测和可能干预ESBL-KP.