重症监护病房呼吸机相关性肺炎患者耐碳青霉烯铜绿假单胞菌菌株的特征。

Characteristics of carbapenem-resistant Pseudomonas aeruginosa strains in patients with ventilator-associated pneumonia in intensive care units.

机构信息

Department of Laboratory Medicine, Medical Academy, Lithuanian University of Health Sciences, Eivenių 2, 50028 Kaunas, Lithuania.

出版信息

Medicina (Kaunas). 2011;47(12):652-6.

PMID:22370463

Abstract

UNLABELLED

The aim of this study was to determine the characteristics of carbapenem-resistant Pseudomonas aeruginosa (P. aeruginosa) strains and 5-year changes in resistance in a tertiary university hospital.

MATERIAL AND METHODS

The study included 90 and 101 randomly selected P. aeruginosa strains serotyped in 2003 and 2008, respectively. The standardized disk diffusion test and E-test were used to determine resistance to antibiotics. P. aeruginosa strains were considered to have high-level resistance if a minimum inhibitory concentration (MIC) for imipenem or meropenem was >32 µg/mL. To identify serogroups, sera containing specific antibodies against O group antigens of P. aeruginosa were used. P. aeruginosa isolates resistant to imipenem or/and meropenem were screened for metallo-β-lactamase (MBL) production by using the MBL E-test.

RESULTS

Comparison of the changes in resistance of P. aeruginosa strains to carbapenems within the 5-year period revealed that the level of resistance to imipenem increased. In 2003, 53.3% of P. aeruginosa strains were found to be highly resistant to imipenem, while in 2008, this percentage increased to 87.8% (P=0.01). The prevalence of MBL-producing strains increased from 15.8% in 2003 to 61.9% in 2008 (P<0.001). In 2003 and 2008, carbapenem-resistant P. aeruginosa strains were more often resistant to ciprofloxacin and gentamicin than carbapenem-sensitive strains. In 2008, carbapenem-resistant strains additionally were more often resistant to ceftazidime, cefepime, aztreonam, piperacillin, and amikacin than carbapenem-sensitive strains. MBL-producing P. aeruginosa strains belonged more often to the O:11 serogroup than MBL-non-producing strains (51.7% vs. 34.3%, P<0.05). A greater percentage of non-MBL-producing strains had low MICs against ciprofloxacin and amikacin as compared with MBL-producing strains.

CONCLUSIONS

The results of our study emphasize the need to restrict the spread of O:11 serogroup P. aeruginosa strains and usage of carbapenems to treat infections with P. aeruginosa in the intensive care units of our hospital.

摘要

目的

本研究旨在确定耐碳青霉烯铜绿假单胞菌（P. aeruginosa）菌株的特征以及在一所三级大学医院中 5 年内耐药性的变化。

材料和方法

本研究纳入了 2003 年和 2008 年随机选择的 90 株和 101 株 P. aeruginosa 血清型菌株。采用标准化纸片扩散试验和 E 试验测定抗生素的耐药性。如果亚胺培南或美罗培南的最低抑菌浓度（MIC）>32μg/ml，则认为铜绿假单胞菌菌株具有高水平耐药性。为了鉴定血清型，使用含有针对铜绿假单胞菌 O 群抗原的特异性抗体的血清。使用 MBL E 试验筛选产金属β-内酰胺酶（MBL）的铜绿假单胞菌分离株。

结果

在 5 年内，比较铜绿假单胞菌对碳青霉烯类药物耐药性的变化发现，对亚胺培南的耐药水平有所增加。2003 年，53.3%的铜绿假单胞菌菌株对亚胺培南高度耐药，而 2008 年这一比例增加到 87.8%（P=0.01）。产 MBL 菌株的流行率从 2003 年的 15.8%上升到 2008 年的 61.9%（P<0.001）。2003 年和 2008 年，耐碳青霉烯类铜绿假单胞菌菌株对环丙沙星和庆大霉素的耐药率均高于碳青霉烯类敏感菌株。2008 年，耐碳青霉烯类铜绿假单胞菌菌株对头孢他啶、头孢吡肟、氨曲南、哌拉西林和阿米卡星的耐药率也高于碳青霉烯类敏感菌株。产 MBL 铜绿假单胞菌菌株比非产 MBL 铜绿假单胞菌菌株更常属于 O:11 血清群（51.7%比 34.3%，P<0.05）。与产 MBL 菌株相比，非产 MBL 菌株对环丙沙星和阿米卡星的 MIC 值较低。