title: Research of the heteroresistance of Pseudomonas aeruginosa to imipenem.
abstract: Pseudomonas aeruginosa (PA) plays plays an important role in nosocomial infection. To explore the heteroresistance of PA to imipenem (IMP), we detected the sensitivity of 140 strains of PA to IMP using the KB method and VITEK method. Combined with resistance mutation analysis, the heteroresistance of PA to IMP was determined. Whilst, the double disk synergy test and SYBGreen RT-PCR for efflux pump were performed in IMP-heteroresistant PA strains. In this study, we confirmed 20 IMP-heteroresistant strains. The double disk synergy tests suggested that none of 20 heteroresistant PA strains produced metalloenzyme. The SYBGreen quantitative RT-PCR revealed that the MexAB expression level of efflux pump in IMP-heteroresistant PA was significantly higher than that in the IMP-sensitive strains (P<0.05), while there was no significantly different between the MexCD expression between resistant strains and sensitive strains (P<0.05). We believe that the clinicians should pay more attention to the PA heteroresistance to IMP, and the heteroesistance of PA to IMP is related to high expression in the MexAB of PA efflux pump.
authors.affiliation: Department of Admission, Shanghai Jiao Tong University Affiliated Sixth People's Hospital Shanghai 200233, China.
authors.forename: Shencong
authors.initials: S
authors.lastname: Mei
authors.affiliation: Department of Laboratory Medicine, Kunshan Hospital Affiliated to Nanjing University of Traditional Chinese Medicine Kunshan 215300, Jiangsu Province, China.
authors.forename: Yulu
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Department of Transfusion, Shanghai Jiao Tong University Affiliated Sixth People's Hospital Shanghai 200233, China ; Department of Laboratory Medicine, Changzhou Tumor Hospital Soochow University Suzhou 213001, China.
authors.forename: Changtai
authors.initials: C
authors.lastname: Zhu
authors.affiliation: Department of Laboratory Medicine, Changzhou Tumor Hospital Soochow University Suzhou 213001, China.
authors.forename: Chunlei
authors.initials: C
authors.lastname: Dong
authors.affiliation: Department of Nursing, Shanghai Jiao Tong University Affiliated Sixth People's Hospital Shanghai 200233, China.
authors.forename: Yawen
authors.initials: Y
authors.lastname: Chen
keywords: Pseudomonas aeruginosa; antimicrobial susceptibility test; heteroresistance; imipenem