论文部分内容阅读
目的分析碳青霉烯耐药肺炎克雷伯菌的临床分布、耐药表型、耐药基因和同源性,为临床抗菌药物的合理使用及减少医院感染的暴发流行提供实验室依据。方法收集宣武医院2015年1月至2016年6月临床分离的碳青霉烯耐药肺炎克雷伯菌菌株,采用Whonet5.6分析耐药情况及分布,产酶表型检测采用改良Hodge试验和碳青霉烯酶失活法(CIM)试验,PCR方法扩增耐药相关基因(KPC、OXA48、NDM、IMP、VIM、TEM、DHA),运用质谱技术分析试验菌的同源性。结果共收集耐碳青霉烯耐药肺炎克雷伯菌50株,占同期该院分离肺炎克雷伯菌的比例为28.1%(50/178),对常用抗菌药物均表现出高耐药性;50例中Hodge试验和耐碳青霉烯失活试验阳性者均占84.0%(42/50),二者同时阳性者占82.0%(41/50),符合率为97.6%。PCR扩增KPC基因型的阳性率为82.0%(41/50),其他耐药基因型阳性检出率分别为TEM 52.0%(26/50)、IMP 20.0%(10/50)、DHA14.0%(7/50)、VIM 12.0%(6/50)、NDM 6.0%(3/50)和OXA48 2.0%(1/50),同时存在3种耐药基因型的菌株占36.0%(18/50),同时存在2种耐药基因型的菌株占26.0%(13/50),未检测到任何耐药基因菌株占10.0%(5/50)。质谱同源性分析分为两大群,包括A1(42.0%)、A2(25.5%)和B(33.3%)型。结论该院碳青霉烯耐药肺炎克雷伯菌的临床分离率高,携带NDM、DHA、IMP、VIM、TEM、OXA-48等多种耐药基因型,以KPC-2基因型最多见;同源性以A型为主要流行株。
Objective To analyze the clinical distribution, drug resistance phenotype, resistance gene and homology of carbapenem-resistant Klebsiella pneumoniae and to provide a laboratory basis for the rational use of clinical antimicrobial agents and reduce the outbreak of nosocomial infection. Methods The clinical isolates of carbapenem-resistant Klebsiella pneumoniae were collected from Xuanwu Hospital from January 2015 to June 2016. The drug resistance and distribution were analyzed by Whonet 5.6. The carbapenemase inactivation assay (CIM) assay was used to amplify the resistance related genes (KPC, OXA48, NDM, IMP, VIM, TEM and DHA) by PCR and the homology of the test bacteria was analyzed by mass spectrometry. Results A total of 50 strains of Klebsiella pneumoniae resistant to carbapenem were collected, accounting for 28.1% (50/178) of the isolates of Klebsiella pneumoniae during the same period. All the commonly used antibiotics showed high drug resistance ; Hodge test and carbapenem inactivation test were positive in 50 cases (84.0%, 42/50), respectively. The positive rate of Hodge test was 82.0% (41/50) in the 50 cases, and the coincidence rate was 97.6%. The positive rate of KPC genotypes by PCR was 82.0% (41/50). The positive rates of other resistant genotypes were TEM 52.0% (26/50), IMP 20.0% (10/50), DHA 14.0 (6/50) of VIM, 6.0% (3/50) of NDM and 2.0% (1/50) of OXA48, and 36.0% of those with three resistant genotypes (18/50) 50). In addition, 26.0% (13/50) strains were found with two resistant genotypes and 10.0% (5/50) were not detected with any resistant gene strains. Mass spectral homology analysis was divided into two large groups, including A1 (42.0%), A2 (25.5%) and B (33.3%). Conclusion The clinical isolates of carbapenem-resistant Klebsiella pneumoniae in this hospital are highly resistant and carry many resistant genotypes such as NDM, DHA, IMP, VIM, TEM and OXA-48. KPC-2 genotype is the most common ; A type as the main homology to epidemic strains.