Division of Infectious Diseases, University of Pittsburgh Medical Center, 200 Lothrop Street, Pittsburgh, PA 15213, USA.
Int J Antimicrob Agents. 2011 Jan;37(1):26-32. doi: 10.1016/j.ijantimicag.2010.09.009. Epub 2010 Nov 13.
Enterobacter cloacae is a major nosocomial pathogen that causes serious infections, including bloodstream infections (BSIs). The clinical significance of extended-spectrum β-lactamase (ESBL) production in E. cloacae is not well established. A multicentre, retrospective, cohort study was conducted to identify clinical characteristics of patients with E. cloacae BSI. ESBL production was confirmed by genotypic methods. A total of 159 patients with E. cloacae BSI were identified at three medical centres in north-eastern USA. Amongst them, 16 patients (10.1%) harboured ESBL-producing E. cloacae. Independent risk factors for ESBL production included admission from a nursing home, the presence of a gastrostomy tube and history of transplant. For the outcome analysis, 15 consecutive patients who had ESBL-producing E. cloacae BSI prior to the study were included. Amongst the 31 patients with ESBL-producing E. cloacae, 8, 9, 4 and 2 patients received a carbapenem, cefepime, piperacillin/tazobactam and ciprofloxacin, respectively, as initial therapy. All patients who received a carbapenem (n=8) were alive at 28 days, whereas 7 (38.9%) of 18 patients who received a non-carbapenem antibiotic did not survive (P=0.06). Clinical failure at 96 h was observed in 2 (25.0%) of 8 patients who received a carbapenem and in 14 (77.8%) of 18 patients who received a non-carbapenem antibiotic (P=0.03). Pulsed-field gel electrophoresis showed little clonality amongst the study isolates. The majority of isolates produced SHV-type ESBL, whereas two isolates produced CTX-M-type ESBL. Initial therapy with a carbapenem appears to be associated with improved clinical outcome in BSI due to ESBL-producing E. cloacae.
阴沟肠杆菌是一种主要的医院获得性病原体，可引起严重感染，包括血流感染（BSI）。产超广谱β-内酰胺酶（ESBL）的阴沟肠杆菌的临床意义尚未得到充分证实。一项多中心、回顾性队列研究旨在确定阴沟肠杆菌 BSI 患者的临床特征。通过基因方法确认 ESBL 产生。在美国东北部的三个医疗中心共发现 159 例阴沟肠杆菌 BSI 患者。其中，16 例（10.1%）携带产 ESBL 的阴沟肠杆菌。ESBL 产生的独立危险因素包括来自疗养院的入院、胃造口管的存在和移植史。在结局分析中，纳入了研究前有产 ESBL 阴沟肠杆菌 BSI 的 15 例连续患者。在 31 例产 ESBL 的阴沟肠杆菌中，分别有 8、9、4 和 2 例患者接受了碳青霉烯类、头孢吡肟、哌拉西林/他唑巴坦和环丙沙星作为初始治疗。接受碳青霉烯类治疗的所有 8 例患者在 28 天内存活，而接受非碳青霉烯类抗生素治疗的 18 例患者中只有 7 例（38.9%）存活（P=0.06）。接受碳青霉烯类治疗的 8 例患者中有 2 例（25.0%）在 96 小时时临床失败，而接受非碳青霉烯类抗生素治疗的 18 例患者中有 14 例（77.8%）（P=0.03）。脉冲场凝胶电泳显示研究分离株之间的克隆性很小。大多数分离株产生 SHV 型 ESBL，而 2 株分离株产生 CTX-M 型 ESBL。在产 ESBL 的阴沟肠杆菌引起的 BSI 中，初始碳青霉烯类治疗似乎与临床结局改善相关。
