临床鲍曼不动杆菌溶血素共调解蛋白基因的表达与耐药及多重感染的相关性

Association of Hcp gene expression with drug resistance and multiple infection in Acinetobacter baumannii isolated from respiratory tract

目的研究临床鲍曼不动杆菌Ⅵ型分泌系统(Type Ⅵ Secretion System,T6SS)及其溶血素共调解蛋白(hemolysincoregulated protein,Hcp)基因的表达与细菌耐药及多重感染的相关性。方法 94株鲍曼不动杆菌来源于温州医科大学附属第二医院2016年6月-2016年9月的住院患者,用PCR技术筛查鲍曼不动杆菌T6SS的关键基因-Hcp基因。再通过qRT-PCR技术检测若干菌株中该基因的表达量。结果 94株鲍曼不动杆菌,携带Hcp基因72株,携带率为76. 6%。经卡方检验,MDRO组与非MDRO组携带率之间的差异有统计学意义(P <0. 05),感染情况、标本来源、科室来源等临床因素与T6SS的存在与否无关。53株携带Hcp基因的分离株,MDRO组该基因的表达量高于非MDRO组(P <0. 05);多重感染组该基因的表达量高于单纯感染组,差异有统计学意义(P <0. 0001)。结论 T6SS在临床鲍曼不动杆菌中广泛存在,某些抗菌药物耐药与多重感染与Hcp基因的表达量呈正相关。

Objective Research on the association of type VI secretion system( T6SS) and hemolysin-coregulated protein( Hcp) gene expression with multidrug resistance and multiple infection in clinical Acinetobacter baumannii. Methods Ninety-four strains of A. baumannii were isolated from hospitalized patients from the Second Affiliated Hospital of Wenzhou Medical University during June 2016-September 2016. Hcp gene,the key gene of A. baumannii T6SS,was screened by PCR technology.Then qRT-PCR was used to detect its expression in some strains. Results In 94 clinical A. baumannii isolates,72 isolates carried Hcp and the carrying rate is 76. 6%( 72/94). The chi square test showed that the difference on the carrying rate of Hcp between MDRO group and non-MDRO group was statistically significant( P < 0. 05),but clinical factors such as infection,source of specimen and departments did not affect the existence of T6SS. To 53 isolates which carried Hcp gene,the expression level of this gene in MDRO group was higher than that in non-MDRO group( P < 0. 05). The expression level of this gene in the multiple infection group was higher than that in the single infection group,with the difference statistically significant( P <0. 000 1). Conclusion T6SS was widespread in clinical A. baumannii,and the expression of Hcp was positively correlated with drug resistance and multiple infection.