Gür Deniz, Gülay Zeynep, Akan Ozay Arikan, Aktaş Zerrin, Kayacan Ciğdem Bal, Cakici Ozlem, Eraç Bayri, Gültekin Meral, Oğünç Dilara, Söyletir Güner, Unal Nilgün, Uysal Sevil
Hacettepe Universitesi Tip Fakültesi, Ihsan Doğramaci Cocuk Hastanesi, Klinik Mikrobiyoloji Laboratuvari, Ankara.
Mikrobiyol Bul. 2008 Oct;42(4):537-44.
Increasing resistance due to extended-spectrum beta-lactamases (ESBLs) and multiple resistance mechanisms in gram-negative hospital isolates restrict the role of beta-lactam antibiotics in empirical treatment of serious infections. As the prevalence of ESBL producing strains and resistance rates to antimicrobial agents can vary in each center, local surveillance studies are required to guide therapy. In this study, in vitro rates of resistance to ceftriaxone, ceftazidime, cefepime, imipenem, cefoperazone/sulbactam and piperacillin/tazobactam were evaluated in 1196 gram-negative hospital isolates in a multicenter in vitro study with the participation of six different centers in Turkey between the period of June 2004-January 2005. The isolates included Escherichia coli (n= 457), Klebsiella pneumoniae (n= 390), Pseudomonas aeruginosa (n= 194) and Acinetobacter boumannii (n= 155). In addition, frequency of ESBL production and types of enzymes were determined in blood isolates of E. coli and K. pneumoniae. MICs and ESBL production were investigated by E-test (AB Biodisk, Solna) and the results were evaluated by using CLSI breakpoints. PCR analysis was used for typing of the ESBLs. In E. coli, 26% and in K. pneumoniae 32% of the isolates were ESBL producers. Among the blood isolates of E. coli and K. pneumoniae, 31.7% and 33.3% produced ESBLs, respectively. CTX-M (71.4%) was the most prevalent enzyme, followed by TEM (49.4%) and SHV (46.7%) derived enzymes. CTX-M-15 (69.4%) was the most frequent CTX-M type in blood isolates followed by CTX-M-3 (28.6%) and CTX-M-1 (2%). Resistance to imipenem was not observed in E. coli isolates, however it was 1.3% in K. pneumoniae, 28.9% in P. aeruginosa and 52.2% in A. baumannii strains. Resistance to cefoperazone/sulbactam was found as 6%, 17.7%, 27.9% and 41.3% in E. coli, K. pneumoniae, P. aeruginosa and A. baumannii isolates, respectively, whereas resistance rates to piperacillin/tazobactam were 10.2%, 22.3%, 22.7% and 78.7%, respectively. These results indicate that ESBL production and rates of resistance to beta-lactam antibiotics are high in hospital isolates of gram-negative bacteria in Turkey, however, they show variations in different hospitals and CTX-M enzymes are prevalent in these isolates.
由于超广谱β-内酰胺酶（ESBLs）导致的耐药性增加以及革兰氏阴性医院分离株中的多种耐药机制，限制了β-内酰胺类抗生素在严重感染经验性治疗中的作用。由于每个中心产ESBL菌株的流行率和对抗菌药物的耐药率可能不同，因此需要进行当地监测研究以指导治疗。在本研究中，2004年6月至2005年1月期间，在土耳其六个不同中心参与的一项多中心体外研究中，对1196株革兰氏阴性医院分离株进行了头孢曲松、头孢他啶、头孢吡肟、亚胺培南、头孢哌酮/舒巴坦和哌拉西林/他唑巴坦的体外耐药率评估。分离株包括大肠杆菌（n = 457）、肺炎克雷伯菌（n = 390）、铜绿假单胞菌（n = 194）和鲍曼不动杆菌（n = 155）。此外，还测定了大肠杆菌和肺炎克雷伯菌血液分离株中ESBL的产生频率和酶的类型。通过E-test（AB Biodisk，索尔纳）研究MIC和ESBL的产生，并使用CLSI断点评估结果。PCR分析用于ESBL的分型。在大肠杆菌中，26%的分离株产ESBL，在肺炎克雷伯菌中这一比例为32%。在大肠杆菌和肺炎克雷伯菌的血液分离株中，分别有31.7%和33.3%产ESBL。CTX-M（71.4%）是最常见的酶，其次是TEM（49.4%）和SHV（46.7%）衍生酶。CTX-M-15（69.4%）是血液分离株中最常见的CTX-M类型，其次是CTX-M-3（28.6%）和CTX-M-1（2%）。在大肠杆菌分离株中未观察到对亚胺培南的耐药性，但在肺炎克雷伯菌中为1.3%，在铜绿假单胞菌中为28.9%，在鲍曼不动杆菌菌株中为52.2%。在大肠杆菌、肺炎克雷伯菌、铜绿假单胞菌和鲍曼不动杆菌分离株中，对头孢哌酮/舒巴坦的耐药率分别为6%、17.7%、27.9%和41.3%，而对哌拉西林/他唑巴坦的耐药率分别为10.2%、22.3%、22.7%和78.7%。这些结果表明，土耳其革兰氏阴性菌医院分离株中ESBL的产生和对β-内酰胺类抗生素的耐药率很高，然而，它们在不同医院存在差异，并且CTX-M酶在这些分离株中很普遍。
