Clinical Microbiology & Public Health Laboratory, Peterborough & Stamford Hospitals NHS Foundation Trust, Peterborough City Hospital, Bretton Gate, Peterborough, UK.
J Hosp Infect. 2012 Aug;81(4):270-7. doi: 10.1016/j.jhin.2012.05.006. Epub 2012 Jun 27.
Extended-spectrum beta-lactamases (ESBLs) are an increasingly important cause of resistance in Gram-negative bacteria throughout the world.
We investigated the clinical and molecular epidemiology of infections caused by ESBL-producing Enterobacteriaceae in a UK hospital, to identify the types of ESBL produced and risk factors for acquisition.
Between July 2008 and June 2009, all patients yielding ESBL-producing Enterobacteriaceae from any clinical specimen were prospectively investigated using a questionnaire. API20E was used for bacterial identification; susceptibility testing and ESBL production were assessed by BSAC disc diffusion and cefpodoxime-clavulanate synergy tests, respectively. Polymerase chain reaction was used to screen a subset of isolates for bla(CTX-M) genes, to assign Escherichia coli isolates to their phylogenetic groups, and to identify members of the uropathogenic ST131 lineage.
The overall prevalence of ESBL producers among clinical samples yielding Enterobacteriaceae was 1%; ESBL producers, obtained from 124 patients, were E. coli (N = 105), Klebsiella pneumoniae (N = 12), and others (N = 7). The main risk factors identified include recent antibiotic use (93%) and presence of a urinary catheter (24%). CTX-M group 1 ESBLs dominated (in 59 of 78, 76%, isolates studied). Most E. coli (35 of 56 tested) were phylogroup B2; of these, 23 belonged to the ST131 clone, 12 were phylogroup D, and four each belonged to phylogroups A and B1.
ESBLs are an uncommon but significant problem in north-west Cambridgeshire. CTX-M-type enzymes were found in 75% of ESBL-positive isolates. All but two patients had at least one recognized risk factor. This study supports the requirement for interventions to reduce inappropriate urinary catheterization and antibiotic prescribing.
超广谱β-内酰胺酶（ESBLs）在全球范围内是革兰氏阴性菌耐药性的一个日益重要的原因。
我们调查了英国一家医院产 ESBL 肠杆菌科细菌感染的临床和分子流行病学，以确定产生的 ESBL 类型和获得的危险因素。
在 2008 年 7 月至 2009 年 6 月期间，对从任何临床标本中产生 ESBL 肠杆菌科细菌的所有患者进行前瞻性调查，使用问卷。API20E 用于细菌鉴定；药敏试验和 ESBL 产生分别通过 BSAC 圆盘扩散和头孢泊肟-克拉维酸协同试验进行评估。聚合酶链反应用于筛选一组分离物 bla(CTX-M)基因，将大肠埃希菌分离物分配到其进化群中，并鉴定尿源性 ST131 谱系的成员。
从临床标本中分离出的产 ESBL 肠杆菌科细菌的总体流行率为 1%；从 124 名患者中获得的 ESBL 生产者是大肠埃希菌（N=105）、肺炎克雷伯菌（N=12）和其他菌（N=7）。确定的主要危险因素包括近期使用抗生素（93%）和存在导尿管（24%）。CTX-M 组 1 ESBL 占主导地位（在所研究的 78 个分离物中，59 个占 76%）。大多数大肠埃希菌（56 个测试中的 35 个）属于进化群 B2；其中，23 个属于 ST131 克隆，12 个属于进化群 D，4 个分别属于进化群 A 和 B1。
ESBL 在剑桥郡西北部是一个不常见但很重要的问题。CTX-M 型酶在 75%的 ESBL 阳性分离物中发现。除了两个患者之外，所有患者都至少有一个公认的危险因素。这项研究支持需要采取干预措施减少不适当的导尿和抗生素的使用。
