Department of Clinical Laboratory, Guangdong Provincial People's Hospital/Guangdong Academy of Medical Sciences, Southern Medical University, Guangzhou 510080, China.
Alfred E. Mann School of Pharmacy and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA.
Zhong Nan Da Xue Xue Bao Yi Xue Ban. 2024 May 28;49(5):730-736. doi: 10.11817/j.issn.1672-7347.2024.240029.
The drug-resistant genes carried by carbapenem-resistant (CRKP) limit clinical treatment options, and its virulence genes severely affect patient prognosis. This study aims to investigate the distribution of virulence genes, capsular serotypes, and molecular epidemiological characteristics of CRKP in ICU, to understand the characteristics of CRKP infections in ICU, and to provide a scientific basis for effective monitoring and control of CRKP infections in ICU.
A total of 40 non-duplicate strains of CRKP isolated from the ICU of Guangdong Provincial People's Hospital between January 2021 and December 2022 were collected and analyzed. Whole-genome sequencing was used to analyze the distribution of resistance genes, virulence genes, and capsular serotypes of the strains. The sequences of 7 housekeeping genes of CRKP genome were uploaded to the (KPN)multilocus sequence typing (MLST) database to determine the sequence types (STs) of the strains.
The age of the 40 ICU CRKP-infected patients was (69.03±17.82) years old, with various underlying diseases, and there were 20 patients with improved clinical outcome and 20 patients with death. The isolated strains primarily originated from mid-stream urine and bronchoalveolar lavage fluid. Whole-genome sequencing results revealed that the strains predominantly carried (29 strains, 72.5%) and (6 strains, 15.0%), with 5 strains carrying both and . Various virulence genes were detected, among which the carriage rates of genes such as , , , , , , , /, and reached 100%, while the carriage rates of genes such as , , , , ,and were low. The CRKP strains isolated from ICU were predominantly ST11 (27 cases, 67.5%), with KL64 being the main capsular serotype (29 cases, 72.5%). A total of 23 ST11-KL64 CRKP strains were detected, accounting for 57.5%.
The main type of ICU CRKP is ST11-KL64, carrying various virulence genes, primarily those related to iron absorption. Furthermore, has shifted from to . Therefore, close monitoring of the molecular epidemiological changes of CRKP is necessary, and strict control measures should be implemented to effectively curb the occurrence of CRKP infections.
碳青霉烯类耐药肠杆菌科细菌（CRKP）携带的耐药基因限制了临床治疗选择，其毒力基因严重影响患者预后。本研究旨在调查 ICU 中 CRKP 的毒力基因、荚膜血清型和分子流行病学特征，了解 ICU 中 CRKP 感染的特点，为有效监测和控制 ICU 中 CRKP 感染提供科学依据。
收集 2021 年 1 月至 2022 年 12 月广东省人民医院 ICU 分离的 40 株非重复 CRKP，采用全基因组测序分析菌株的耐药基因、毒力基因和荚膜血清型分布，将 CRKP 基因组 7 个管家基因序列上传至 （KPN）多位点序列分型（MLST）数据库，确定菌株的序列型（ST）。
40 例 ICU CRKP 感染患者的年龄为（69.03±17.82）岁，基础疾病多样，20 例患者临床转归改善，20 例患者死亡。分离株主要来源于中段尿和支气管肺泡灌洗液。全基因组测序结果显示，菌株主要携带 （29 株，72.5%）和 （6 株，15.0%），5 株同时携带 和 。检测到多种毒力基因，其中 、 、 、 、 、 、/、 等基因的携带率均为 100%，而 、 、 、 、 、 等基因的携带率较低。ICU 分离的 CRKP 菌株主要为 ST11（27 株，67.5%），主要荚膜血清型为 KL64（29 株，72.5%）。共检测到 23 株 ST11-KL64 CRKP 菌株，占 57.5%。
ICU 中 CRKP 的主要类型为 ST11-KL64，携带多种毒力基因，主要与铁吸收相关， 从 转移到 。因此，有必要密切监测 CRKP 的分子流行病学变化，实施严格的控制措施，有效遏制 CRKP 感染的发生。
