Department of Pharmaceutics and Microbiology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
Burns. 2012 Sep;38(6):855-60. doi: 10.1016/j.burns.2012.01.005. Epub 2012 Feb 19.
We determined the prevalence rate of classes A, B and D β-lactamases among extended-spectrum cephalosporin (ESC)-non-susceptible Pseudomonas aeruginosa clinical isolates from burned patients.
Disc susceptibility testing was performed on 156 P. aeruginosa isolates collected during 2010 at Prince Salman Hospital in Riyadh, Saudi Arabia. Phenotypic screening of ESBLs and MBLs in the isolates resistant to ceftazidime (MIC>8 mg/L) was carried out. Genes encoding ESBLs and MBL were sought by PCR in ESBL- and MBL-producing isolates.
The resistance rate to ceftazidime was 22.43%. The resistance rates for ESC-non-susceptible P. aeruginosa isolates to piperacillin, piperacillin/tazobactam, cefepime, aztreonam, imipenem, amikacin, gentamicin and ciprofloxacin were 100%, 71.14%, 88.57%, 48.57%, 70.0%, 82.5%, 87.5%, and 90.0% respectively. No resistance was detected to polymyxine B. The prevalence of ESBL and MBL in ESC-non-susceptible P. aeruginosa was 69.44% and 42.85%, respectively. The prevalence of structural genes for VEB-1, OXA-10 and GES ESBLs in P. aeruginosa was 68%, 56% and 20%, respectively. VIM gene was detected in 15 (100%) of MBL-producing isolates. OXA-10 like gene was concomitant with VEB, GES and/or VIM. Eight isolates harbored OXA-10 with VEB (imipenem MIC 6-8 mg/L), while five isolates harbored OXA-10 with VIM (imipenem MIC ≥ 32 mg/L) and one isolate contained OXA-10, VEB and GES (imipenem MIC 8 mg/L). PER was not detected in this study.
VEB-1 and OXA-10 are the predominant ESBL genes and bla(VIM) is the dominate MBL gene in ESC-non-sensitive P. aeruginosa isolates in Saudi Arabia. VEB, OXA-10 and GES ESBLs have not been reported previously in Saudi Arabia and GES has not been reported previously in Middle East and North Africa.
我们确定了来自烧伤患者的对扩展谱头孢菌素（ESC）不敏感的铜绿假单胞菌临床分离株中 A、B 和 D 类β-内酰胺酶的流行率。
对 2010 年在沙特阿拉伯利雅得王子萨尔曼医院收集的 156 株铜绿假单胞菌分离株进行了药敏纸片检测。对头孢他啶（MIC>8mg/L）耐药的分离株进行了超广谱β-内酰胺酶（ESBLs）和金属β-内酰胺酶（MBLs）的表型筛选。通过 PCR 在产 ESBL 和 MBL 的分离株中寻找编码 ESBLs 和 MBLs 的基因。
头孢他啶的耐药率为 22.43%。对哌拉西林、哌拉西林/他唑巴坦、头孢吡肟、头孢噻肟、亚胺培南、阿米卡星、庆大霉素和环丙沙星耐药的 ESC 非敏感铜绿假单胞菌分离株的耐药率分别为 100%、71.14%、88.57%、48.57%、70.0%、82.5%、87.5%和 90.0%。对多黏菌素 B 无耐药性。在 ESC 非敏感铜绿假单胞菌中，ESBL 和 MBL 的流行率分别为 69.44%和 42.85%。铜绿假单胞菌中 VEB-1、OXA-10 和 GES ESBLs 的结构基因流行率分别为 68%、56%和 20%。15 株（100%）产 MBL 的分离株中均检测到 VIM 基因。OXA-10 样基因与 VEB、GES 和/或 VIM 同时存在。8 株分离株携带 OXA-10 和 VEB（亚胺培南 MIC 6-8mg/L），5 株分离株携带 OXA-10 和 VIM（亚胺培南 MIC≥32mg/L），1 株分离株携带 OXA-10、VEB 和 GES（亚胺培南 MIC 8mg/L）。本研究未检测到 PER。
在沙特阿拉伯，ESC 不敏感铜绿假单胞菌分离株中 VEB-1 和 OXA-10 是主要的 ESBL 基因，bla（VIM）是主要的 MBL 基因。VEB、OXA-10 和 GES ESBLs 以前在沙特阿拉伯没有报道过，GES 以前在中东和北非也没有报道过。
