| 摘要: |
| 目的 了解医院耐碳青霉烯类肺炎克雷伯菌（CRKP）的分布特点、耐药性和分子生物学特征，为指导临床合理使用抗菌药物、防控CRKP院内传播提供依据。方法 收集我院2019年1月至12月临床分离的非重复CRKP菌株，采用VITEK 2 Compact全自动微生物分析仪和纸片扩散法（Kirby-Bauer法）进行细菌鉴定和药物敏感试验，采用WHONET 5.6软件对CRKP的检出率、标本来源、临床科室分布等进行统计分析。通过拉丝试验筛选高黏表型菌株，PCR检测碳青霉烯酶耐药基因、荚膜血清型和毒力基因。结果 共检出肺炎克雷伯菌532株，其中CRKP 140株（26.3%）。CRKP菌株主要分离自痰/支气管肺泡灌洗液（66株，47.1%），其次为尿液（21株，15.0%）。临床科室分布主要为心血管外科ICU（47株，33.6%）、烧伤科ICU（18株，12.9%）和急诊科（18株，12.9%）。药物敏感试验结果显示CRKP除对替加环素敏感外，对其他抗菌药物的耐药率均在50%以上，其中对第1～4代头孢菌素类抗生素的耐药率均在85%以上，对碳青霉烯类药物的耐药率最高可达100.0%。耐药基因检测结果显示，121株CRKP中检出101株（83.5%）携带肺炎克雷伯菌碳青霉烯酶2（KPC-2）1种基因，7株（5.8%）携带苯唑西林酶48（OXA-48）1种基因，2株（1.7%）携带新德里金属β-内酰胺酶1（NDM-1）1种基因，1株同时携带KPC-2和NDM-1基因，1株同时携带KPC-2和OXA-48基因，9株未检出目的耐药基因。15株（12.4%，15/121）CRKP拉丝试验阳性，其中13株为K64荚膜型，2株为K47荚膜型；14株检测到至少1种毒力基因。结论 我院CRKP临床分离率高，对多种抗菌药物耐药，以K64荚膜型高毒力CRKP为主，提示临床应进一步加强耐药监测，合理使用抗菌药物，以防止耐药菌株和高毒力菌株的传播和流行。 |
| 关键词: 肺炎克雷伯菌 耐碳青霉烯类肺炎克雷伯菌 细菌抗药性 高黏表型 毒力 |
| DOI：10.16781/j.0258-879x.2020.10.1109 |
| 投稿时间：2020-08-27修订日期：2020-09-25 |
| 基金项目:海军军医大学（第二军医大学）长海医院青年启动基金（2019QNB08），军队生物安全重点专项课题（19SWAQ06）． |
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| Epidemiological characteristics and molecular biology of carbapenem-resistant Klebsiella pneumoniae |
| LI Xue-jiao△,MA Wei△,GUO Jie,WAN Yu-xiang,LI Ya-zhou,QIN Qin* |
(Department of Laboratory Medicine, Changhai Hospital, Naval Medical University(Second Military Medical University), Shanghai 200433, China
△Co-first authors.
* Corresponding author) |
| Abstract: |
| Objective To investigate the distribution, drug resistance and molecular biological characteristics of carbapenem-resistant Klebsiella pneumoniae (CRKP) in our hospital, so as to provide reference for rational use of antibiotics and prevention and control of nosocomial CRKP infection. Methods Non-repetitive CRKP strains were collected from Jan. to Dec. 2019 in our hospital. VITEK 2 Compact automatic microbial analyzer and Kirby-Bauer test were used for bacterial identification and antimicrobial susceptibility analysis. WHONET 5.6 software was used to analyze CRKP detection rate, sample source and clinical department distribution. Hypermucoviscosity phenotype strains were screened by string test. Carbapenemase resistance genes, capsular serotype and virulence genes were detected by polymerase chain reaction (PCR). Results A total of 532 Klebsiella pneumoniae strains were detected, including 140 (26.3%) CRKP strains. The CRKP strains were mainly isolated from sputum and bronchoalveolar lavage fluid (66 strains, 47.1%), followed by urine (21 strains, 15.0%). The clinical departments of the isolates were mainly cardiovascular surgery intensive care unit (ICU) (47 strains, 33.6%), burn ICU (18 strains, 12.9%) and emergency department (18 strains, 12.9%). The antimicrobial susceptibility test showed that the CRKP strains were susceptible only to tigecycline, with resistance rates being over 50% to other common antibiotics. The resistance rates to the first to fourth generation cephalosporin antibiotics were above 85%, and the resistance rates to carbapenems were up to 100.0%. We also found that out of the 121 CRKP strains, 101 (83.5%) carried Klebsiella pneumoniae carbapenemase 2 (KPC-2) gene, seven (5.8%) with oxacillinase-48 (OXA-48) gene, and two (1.7%) with New Delhi metallo-β-lactmase 1 (NDM-1) gene; while one carried both KPC-2 and NDM-1 genes, and one carried both KPC-2 and OXA-48 genes; and nine carried no target drug-resistance genes. Fifteen (12.4%, 15/121) CRKP strains were positive for string test, with 13 being K64 capsular type and two being K47 capsular type; and 14 strains carried at least one virulence gene. Conclusion The clinical isolation rate of CRKP is high in our hospital, and the CRKP strains (mainly K64 capsular high virulence) are resistant to multiple antibiotics, suggesting that we should further strengthen the monitoring of drug resistance and rational use of antibiotics, so as to prevent the spread and prevalence of drug-resistant and highly virulent strains. |
| Key words: Klebsiella pneumoniae carbapenem-resistant Klebsiella pneumoniae bacterial drug resistance hypermucoviscosity phenotype virulence |
