Nowak Pawel, Paluchowska Paulina, Budak Alicja
Department of Pharmaceutical Microbiology, Jagiellonian University Medical College, Krakow, Poland.
New Microbiol. 2012 Jul;35(3):317-25. Epub 2012 Jun 30.
Acinetobacter baumannii is an important nosocomial pathogen occurring particularly in intensive care (ICU) as well as burn therapy units (BTU). A. baumannii strains have emerged as resistant to almost all antimicrobial agents, including carbapenems. b-lactamase-mediated resistance is the most common mechanism for carbapenem resistance in this species. Carbapenem-hydrolysing class D b-lactamases - OXA are widespread among A. baumannii strains. It is suggested that ISAba1 plays an important role in drug resistance. The aims of the study were detection of OXA encoding genes and presence of ISAba1. The study included the total of 104 isolates of carbapenem-resistant A. baumannii, obtained from patients hospitalized in ICU and BTU of Specialized Hospital in Krakow. Multiplex PCR was applied for detection of selected OXA carbapenemases encoding genes. PCR analysis showed the presence of bla OXA-51-like gene and ISAba1 in all isolates. 46 strains carried bla OXA-51-like and bla OXA-23-like genes while 48 bla OXA-51-like and bla OXA-40-like genes. 3 isolates carried: bla OXA-51-like , bla OXA-23-like and bla OXA-40-like genes. 7 strains encoded an OXA-51-like carbapenemase but were negative for enzymes belonging to the other families tested. Comparative analysis of ICU and BTU isolates revealed the dominance of: bla OXA-51-like and bla OXA-40-like among ICU while bla OXA-51-like and bla OXA-23-like in BTU.
鲍曼不动杆菌是一种重要的医院病原体，尤其在重症监护病房（ICU）以及烧伤治疗病房（BTU）中出现。鲍曼不动杆菌菌株已对几乎所有抗菌药物产生耐药性，包括碳青霉烯类。β-内酰胺酶介导的耐药性是该物种对碳青霉烯耐药的最常见机制。碳青霉烯水解D类β-内酰胺酶——OXA在鲍曼不动杆菌菌株中广泛存在。有人认为ISAba1在耐药性中起重要作用。该研究的目的是检测OXA编码基因和ISAba1的存在。该研究共纳入了104株耐碳青霉烯鲍曼不动杆菌分离株，这些分离株来自克拉科夫专科医院ICU和BTU住院患者。采用多重PCR检测选定的OXA碳青霉烯酶编码基因。PCR分析显示所有分离株中均存在bla OXA-51样基因和ISAba1。46株携带bla OXA-51样和bla OXA-23样基因，48株携带bla OXA-51样和bla OXA-40样基因。3株携带：bla OXA-51样、bla OXA-23样和bla OXA-40样基因。7株编码OXA-51样碳青霉烯酶，但对其他测试家族的酶呈阴性。ICU和BTU分离株的比较分析显示：ICU中以bla OXA-51样和bla OXA-40样为主，而BTU中以bla OXA-51样和bla OXA-23样为主。
