Graduate School, Khon Kaen University.
Jpn J Infect Dis. 2013;66(5):428-32. doi: 10.7883/yoken.66.428.
A total of 121 Escherichia coli (47 extended-spectrum β-lactamase [ESBL] and 74 non-ESBL producers) and 75 Klebsiella pneumoniae isolates (49 ESBL and 26 non-ESBL producers) were collected from urine samples between October 2010 and April 2011 at a university hospital and assessed for the presence of plasmid-mediated quinolone resistance (PMQR) genes. Twenty-seven E. coli (22.3%) and 49 K. pneumoniae (65.3%) isolates harbored PMQR genes, which mostly consisted of aac(6')-Ib-cr and qnrS, followed by qnrB and qnrA. Among the 76 PMQR-positive isolates, 15 (19.7%) and 2 (2.6%) carried 2 and 3 different PMQR genes, respectively. However, qnrC, qnrD, and qepA were not found in any isolate. The PMQR genes were more prevalent in ESBL producers than in non-ESBL producers (42.6% versus 9.5% in E. coli and 81.6% versus 34.6% in K. pneumoniae). Approximately 35%-60% of the PMQR-positive isolates were susceptible or intermediately susceptible to fluoroquinolones. The enterobacterial repetitive intergenic consensus-PCR method revealed that most PMQR-positive isolates belonged to different strains, indicating the spread of these resistance determinants. PMQR gene transfer by conjugation was successful in 10%-25% of the test donors. This study showed a high prevalence of PMQR genes among both organisms. Clinical use of fluoroquinolones for the treatment of infections caused by fluoroquinolone-susceptible strains harboring PMQR genes may lead to decreased therapeutic efficacy.
共从 2010 年 10 月至 2011 年 4 月在一所大学医院采集了 121 株大肠埃希菌（47 株产超广谱β-内酰胺酶[ESBL]和 74 株非产 ESBL 株）和 75 株肺炎克雷伯菌分离株（49 株产 ESBL 和 26 株非产 ESBL），并评估了质粒介导的喹诺酮类耐药（PMQR）基因的存在。27 株大肠埃希菌（22.3%）和 49 株肺炎克雷伯菌（65.3%）分离株携带 PMQR 基因，主要由 aac(6')-Ib-cr 和 qnrS 组成，其次是 qnrB 和 qnrA。在 76 株 PMQR 阳性分离株中，有 15 株（19.7%）和 2 株（2.6%）分别携带 2 种和 3 种不同的 PMQR 基因。然而，任何分离株均未发现 qnrC、qnrD 和 qepA。PMQR 基因在 ESBL 生产者中比在非 ESBL 生产者中更为普遍（大肠埃希菌中分别为 42.6%和 9.5%，肺炎克雷伯菌中分别为 81.6%和 34.6%）。大约 35%-60%的 PMQR 阳性分离株对氟喹诺酮类药物敏感或中度敏感。肠杆菌重复基因间共识-PCR 方法显示，大多数 PMQR 阳性分离株属于不同的菌株，表明这些耐药决定因素的传播。通过接合试验，PMQR 基因的转移成功率为 10%-25%的供体。本研究显示，两种菌中 PMQR 基因的流行率均很高。临床使用氟喹诺酮类药物治疗携带 PMQR 基因的氟喹诺酮类药物敏感菌株引起的感染可能会导致治疗效果降低。
