南阳地区肿瘤患者化疗后肺部感染铜绿假单胞菌致病基因检测及其分布情况分析

Analysis of pathogenic genes of Pseudomonas aeruginosaisolated from patients with a lung infection after chemotherapy to treat a tumor in the Nanyang region

目的检测南阳地区肿瘤患者化疗后肺部感染铜绿假单胞菌致病基因,分析铜绿假单胞菌致病基因分布情况。方法收集南阳地区各医院化疗后的肿瘤住院患者痰标本,分离铜绿假单胞菌并提取基因组DNA,PCR扩增致病基因exoS和exoU,并观察致病基因分布情况。结果 exoS基因PCR扩增片段大小为573bp,exoU基因片段大小为428bp;68株铜绿假单胞菌中两种致病基因的分布存在差异,仅有1株同时存在两种致病基因(exoS+exoU+),占1.47%;44株仅检测到exoS基因而未检测到exoU基因(exoS+exoU-),占64.71%;7株仅检测到exoU+基因而未检测到exoS基因(exoS-exoU+),占10.29%;两种致病基因均阴性15株(exoS-exoU-),占23.53%。结论肿瘤患者化疗后肺部感染的铜绿假单胞菌,exoS和exoU基因携带率较高,可供临床治疗时参考。

Objective To analyze the pathogenic genes of Pseudornonas aeruginosa isolated from patients with a Iung in- fection after chemotherapy to treat a tumor in the City of Nanyang in order to study the pathogenic characteristics of P. aeruginosa. Methods Sputum samples were collected from patients with a lung infection after chemotherapy to treat a tumor in the City of Nanyang. P. aeruginosa was isolated and genomic DNA was extracted. The pathogenic genes exoS and exoU were amplified with PCR and their distribution was examined. Results Results of PCR amplification indicated that the exoS gene was 573 bp in length and that the exoU gene was 428 bp in length. The distribution of the 2 pathogenic genes differed in 68 strains of P. aeruginosa. Only 1 strain had both pathogenic genes （exoSq-exoUq-）, accounting for 1. 470/00 of the total strains. Forty-four strains had the exoS gene but not the exoU gene （exoS＋exoU-）, accounting for 64.71~. Seven strains had the exoU gene hut not the exoS gene （exoS-exoU＋） , accounting for 10.29~~. Fifteen strains had neither pathogenic genes （exoS-exoU-）, accounting for 23.53 ~. Results indicated that P. aeruginosa was likely to have one or both of the pathogenic genes. These genes can be sequenced to determine the mechanisms of the pathogenicity of P. aeruginosa. Conclusion P. aeruginosa that infected patients with a lung infection after chemotherapy to treat a tumor was likely to have one or both pathogenic genes. Studying pathogenic factors in depth can prevent the outbreak of a new epidemic in Nanyang.