鼻咽癌放射治疗患者分离的铜绿假单胞菌同源性分析

Homology analysis of Pseudomonas aeruginosa isolated from nasopharyngeal carcinoma patients undergoing radiotherapy

目的研究分析某院鼻咽癌放射治疗(放疗)患者临床标本分离的铜绿假单胞菌(PA)基因型别同源关系及危险因素,预防和控制感染传播。方法采用BD phoenix 100全自动微生物鉴定系统鉴定临床标本分离菌,应用随机引物扩增多态性DNA(RAPD)技术进行基因检测分析。结果 43例鼻咽癌放疗患者临床标本分离的49株PA主要来源于咽拭子(46.94%)、痰(32.65%)和口腔分泌物(10.20%)标本。49株菌样共扩增电泳出46个电泳图谱,分19个基因型。高度同源的H型菌株和J型菌株分别在放疗二区和放疗四区的分布达57.14%(4/7)和60.00%(3/5)。结论该院不同病区之间存在高度同源PA的局部流行,病区之间的患者交换是同源PA感染/定植的危险因素。应用RAPD等基因分型技术检测分析医院感染病原菌的同源性,对防控感染传播具有重要意义。

Objective To study the risk factors of Pseudomonas aeruginosa （PA） infection and homology of PA isolated from nasopharyngeal carcinoma patients undergoing radiotherapy, and prevent and control the spread of in- fection. Methods Bacteria isolated from clinical specimens were identified by BD Phoenix automated microbiology system. Gene homology were analyzed with randomly amplified polymorphic DNA （RAPD） technique. Results Forty-nine strains of PA were mainly isolated from 43 nasopharyngeal carcinoma patients, the major specimens were nasopharyngeal swab （46. 94%）, sputum（32.65%）, and oral secretion （10.20%）. All these strains were amplified 46 electrophore- sis diagrams, and 19 genotypes were identified. The highly homologous genotypes of type H and J strains were mainly isolated from patients in the second section （57.14%,4/7） and fourth section （60.00% ,3/5） of radiotherapy department respectively. Conclusion Localized epidemic of highly homologous PA exists in different sections of ward, transfer of patients between different sections is the risk factor for homology PA infection/colonization. Gen- otyping technique such as RAPD for analyzing the homology of pathogenic bacteria in healthcare-associated infection has important value in preventing and control Ling infection spread.