Budak S, Oncul O, Aktas Z, Acar A, Ozyurt M, Turhan V, Erdem H, Gorenek L
Southeast Asian J Trop Med Public Health. 2014 Jan;45(1):113-22.
We aimed to investigate carbapenem resistance, resistance mechanisms, risk factors and epidemiological features of Escherichia coli and Klebsiella pneumoniae strains isolated from related infections in intensive care unit (ICU) patients. Carbapenemase activity was determined by MHT, MBL Etest and enzyme extraction methods. Presence of extended-spectrum beta-lactamase (ESBL) and carbapenemase-encoding genes were investigated by PCR and sequencing. Clonal relationship of the strains was investigated by pulse field gel-electrophoresis. Acquired AmpC and Qnr were investigated by PCR. Throughout this study, 1,657 patients, and 11,483 hospitalization days were followed by active surveillance in the ICU of our 1,000-bed training hospital. Out of 108 of 196 patients, 130 E. coli- and K. pneumoniae-related nosocomial infections were determined. Minimum inhibitory concentration (MIC) levels of ertapenem were > or = 1 mg/1 in 14 K. pneumoniae and 2 E. coli strains. The highest MIC level of carbapenem was found in K. pneumoniae and E. coli strains of > or = 128 mg/l and 8 mg/l, respectively. In the carbapenem resistant strains, KPC and MBL activity were not found. On the other hand, 14 strains of K. pneumoniae and one strain of E. coli exhibited OXA-48 beta-lactamase activity. Fifty-seven percent of K. pneumoniae isolates produced OXA-48 orginating from two clones and remaining isolates originated from different clones. Thus carbapenem resistance was determined as 22% and 3% in K. pneumoniae and E. coli strains, respectively. Invasive devices, duration of total parenteral nutrition, duration of hospitalization, presence of transfusions, ESBL and multiple drug resistance were found to be risk factors for carbapenem resistance.
我们旨在调查从重症监护病房（ICU）患者相关感染中分离出的大肠杆菌和肺炎克雷伯菌菌株的碳青霉烯耐药性、耐药机制、危险因素及流行病学特征。通过MHT、MBL Etest和酶提取方法测定碳青霉烯酶活性。采用PCR和测序技术研究超广谱β-内酰胺酶（ESBL）和碳青霉烯酶编码基因的存在情况。通过脉冲场凝胶电泳研究菌株的克隆关系。采用PCR技术研究获得性AmpC和Qnr。在我们拥有1000张床位的教学医院的ICU中，对1657例患者和11483个住院日进行了主动监测。在196例患者中的108例中，确定了130例与大肠杆菌和肺炎克雷伯菌相关的医院感染。14株肺炎克雷伯菌和2株大肠杆菌中厄他培南的最低抑菌浓度（MIC）水平≥1mg/L。碳青霉烯类药物的最高MIC水平分别在肺炎克雷伯菌和大肠杆菌菌株中达到≥128mg/L和8mg/L。在碳青霉烯耐药菌株中，未发现KPC和MBL活性。另一方面，14株肺炎克雷伯菌和1株大肠杆菌表现出OXA-48β-内酰胺酶活性。57%的肺炎克雷伯菌分离株产生源自两个克隆的OXA-48，其余分离株源自不同克隆。因此，肺炎克雷伯菌和大肠杆菌菌株中的碳青霉烯耐药率分别确定为22%和3%。侵入性装置、全胃肠外营养持续时间、住院时间、输血情况、ESBL和多重耐药被发现是碳青霉烯耐药的危险因素。
