Distribution of integrons and phylogenetic groups among highly virulent serotypes of Klebsiella pneumoniae in a Chinese tertiary hospital
Distribution of integrons and phylogenetic groups among highly virulent serotypes of Klebsiella pneumoniae in a Chinese tertiary hospital
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中国某三甲医院肺炎克雷伯菌高毒力血清型整合子及系统发育群分布
DOI：
10.1016/j.jgar.2019.11.016
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发表时间：
2020-01-01
影响因子：
4.6
通讯作者：
Liu, Yang
中科院分区：
文献类型：
--
作者：
Liao, Wenjian;Li, Dan;Liu, Yang
目的：研究中国某三级医院临床高毒血清型肺炎克雷伯菌分离株整合子的分布和系统发育群。方法：对90株临床分离的肺炎克雷伯菌进行1、2、3类整合酶的PCR鉴定。药敏试验采用纸片扩散法。采用多位点序列分型（MLST）和脉冲场凝胶电泳（PFGE）对HVS肺炎克雷伯菌分离株进行基因型分析。结果：90株分离株中K1、K2、K20、K54和K57血清型分别占54.5%、21.1%、1.1%、18.9%和4.4%。在50株整合子阳性菌株中，48株（96%）和2株（4%）分别被分类为1类（intI1）和2类（intI2）整合子。编码对甲氧苄啶（dfr）和氨基糖苷（aac, aad）抗性的基因盒在1类整合子中占主导地位。此外，HVS肺炎克雷伯菌分离株中最常见的序列型（ST）为ST23(49/90; 54.4%)，其次为ST29（11/90; 12.2%）、ST86（10/90; 11.1%）、ST65（9/90; 10.0%）、ST15（6/90; 6.7%）、ST412（4/90; 4.4%）和ST34（1/90; 1.1%）。结论：某三级医院HVS肺炎克雷伯菌分离株中整合子阳性率较高（55.6%）。1类整合子最为显著，其变异区多态化。HVS肺炎克雷伯菌分离株中整合子的存在导致抗菌素耐药性增加。(c) 2019年Elsevier Ltd代表国际抗微生物化疗学会发表。
Objectives: This study describes the distribution of integrons and phylogenetic groups among clinical highly virulent serotype (HVS) Klebsiella pneumoniae isolates in a Chinese tertiary hospital.Methods: Class 1, 2 and 3 integrases were identified by PCR in 90 clinical isolates of HVS K. pneumoniae. Antimicrobial susceptibility was determined by the disk diffusion method. Multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) were used to analyse the genotypes of the HVS K. pneumoniae isolates.Results: Serotypes K1, K2, K20, K54 and K57 accounted for 54.5%, 21.1%, 1.1%, 18.9% and 4.4% of the 90 isolates. Among the 50 integron-positive isolates, 48 (96%) and 2 (4%) were classified as having class 1 (intI1) and class 2 (intI2) integrons, respectively. Gene cassettes encoding resistance to trimethoprim (dfr) and aminoglycosides (aac, aad) were found to be predominant in class 1 integrons. In addition, the most prevalent sequence type (ST) among the HVS K. pneumoniae isolates was ST23 (49/90; 54.4%), followed by ST29 (11/90; 12.2%), ST86 (10/90; 11.1%), ST65 (9/90; 10.0%), ST15 (6/90; 6.7%), ST412 (4/90; 4.4%) and ST34 (1/90; 1.1%).Conclusion: In summary, a high prevalence of integrons (55.6%) was found among HVS K. pneumoniae isolates in a Chinese tertiary hospital. Class 1 integrons were the most predominant and their variable regions were polymorphic. The presence of integrons in HVS K. pneumoniae isolates results in increased antimicrobial resistance. (c) 2019 Published by Elsevier Ltd on behalf of International Society for Antimicrobial Chemotherapy.