Franiczek Roman, Dolna Izabela, Krzyzanowska Barbara, Szufnarowski Krzysztof, Kowalska-Krochmal Beata, Zielińska Marzena
Katedra i Zakład Mikrobiologii Akademii Medycznej we Wrocławiu.
Med Dosw Mikrobiol. 2006;58(1):41-51.
The aim of this study was to evaluate the transfer frequency of plasmids encoding extended-spectrum beta-lactamases (ESBLs) from clinical isolates of Enterobacteriaceae to E. coli K12 C600 recipient strain. Additionally, resistance patterns to antimicrobial drugs of the isolates as well as transconjugants were analyzed. Fifty-four clinical strains belonging to the Enterobacteriaceae family were isolated from children hospitalized in Medical University Hospital in Wrocław. All the strains studied were identified in automatic ATB system using ID32E tests. Besides, they were ESBL-positive as was confirmed by the double-disc synergy test (DDST). The minimal inhibitory concentration (MIC) was determined for twelve selected antibiotics and chemotherapeutics. The majority of the strains (87%) were able to transfer plasmid-mediated ESBL to E. coli K12 C600 recipient strain with a frequencies ranged from 10(-5) to 10(-1) per donor cell. All the isolates studied as well as their transconjugants were susceptible to imipenem, meropenem and norfloxacin (MIC <1mg/L). On the other hand, these strains displayed high level of resistance (MIC 512 - >1024 mg/L) to cefotaxime, ceftriaxone, gentamycin, amikacin and cotrimoxazole. Genetic markers conferring resistance to aminoglycosides and cotrimoxazole were often co-transferred to recipient strain in conjugation process.
本研究的目的是评估编码超广谱β-内酰胺酶（ESBLs）的质粒从肠杆菌科临床分离株向大肠杆菌K12 C600受体菌株的转移频率。此外，还分析了分离株以及转接合子对抗菌药物的耐药模式。从弗罗茨瓦夫医科大学医院住院儿童中分离出54株属于肠杆菌科的临床菌株。所有研究菌株均使用ID32E测试在自动ATB系统中进行鉴定。此外，通过双碟协同试验（DDST）证实它们为ESBL阳性。测定了12种选定抗生素和化疗药物的最低抑菌浓度（MIC）。大多数菌株（87%）能够将质粒介导的ESBL转移至大肠杆菌K12 C600受体菌株，转移频率为每个供体细胞10^(-5)至10^(-1)。所有研究的分离株及其转接合子对亚胺培南、美罗培南和诺氟沙星敏感（MIC<1mg/L）。另一方面，这些菌株对头孢噻肟、头孢曲松、庆大霉素、阿米卡星和复方新诺明表现出高水平耐药（MIC 512->1024mg/L）。赋予对氨基糖苷类和复方新诺明耐药性的遗传标记在接合过程中常共同转移至受体菌株。
