ICU多重耐药铜绿假单胞菌外排泵基因表达分子流行趋势及其危险因素

Molecular epidemiology and its risk factors of efflux pump of multi-drug resisitant Pseudomonas Aeruginosa isolated from ICU

目的探讨ICU患者中多重耐药铜绿假单胞菌(MDRPA)多药物外排泵基因Mex AB-Opr M、Mex CD-Opr J、MexEF-Opr N表达的分子流行趋势及其危险因素。方法收集2012年4月-2014年2月本院ICU病房收治的56例确诊感染MDRPA患者的痰、血或创面分泌物标本,分离培养MDRPA菌共56株,应用聚合酶链式反应(PCR)及实时荧光定量PCR(real-time PCR)等方法分析上述标本中3种外排泵基因表达的情况。结果 56株MDRPA菌中,Mex ABOpr M、Mex CD-Opr J及Mex EF-Opr N阳性菌株数分别为55(98.2%)、10(17.9%)和23(41.1%);Mex AB-Opr M、MexCD-Opr J及Mex EF-Opr N阳性菌株中高表达者分别为23例(23/55)、4例(4/10)和14例(14/23);Logistic回归分析显示,碳青酶烯类抗生素应用、留置深静脉导管及糖皮质激素应用超过1周是Mex AB-Opr M、Mex CD-Opr J及Mex EFOpr N高表达的独立危险因素。结论多重耐药铜绿假单胞菌多药物外排泵基因Mex AB-Opr M阳性率较高,其高表达与碳青酶烯类抗生素应用、留置深静脉导管及激素应用超过1周有关。

Objective To evaluate the molecular epidemiology and risk factors of the efflux pumps（ MexAB-OprM,MexCD-OprJ,MexEF-OprN） of multi-drug resistant Pseudomonas aeruginosa（ MDRPA） from patients in ICU. Methods Specimens were collected from the sputum,blood and wound secretion of 56 subjects with confirmed diagnosis of MDRPA from Apr.2012 to Feb. 2014. And 56 strains of MDRPA were isolated and cultured foranalyzing the expression of those three efflux pumps by polymerase chain reaction（ PCR） and real time-PCR. Results Among the 56 strains of MDRPA,the positive rate of MexAB-OprM,MexCD-OprJ,MexEF-OprN were 55（ 98. 2%）,10（ 17. 9%） and 23（ 41. 1%）,respectively. The over expression in MexAB-OprM,MexCD-OprJ,MexEF-OprN positive specimen were 23（ 23 /55）,4（ 4 /10） and 14（ 14 /23）. The logistic regression analysis indicated that carbon blue enzyme alkenes antibiotic application,deep vein catheter and glucocorticoids application more than 1 week were independent risk factors for MexAB-OprM,MexCD-OprJ,MexEF-OprN over expression.Conclusion The positive rate of MexAB-OprM,the efflux pumps over expression was relative high in multiple drug resistant Pseudomonas aeruginosa,which was associated with carbon blue enzyme alkenes antibiotic application,deep vein catheter and glucocorticoids application more than 1 week.