鲍曼不动杆菌β-内酰胺酶耐药基因研究

Study on the genes for beta-lactamases in Acinetobacter baumannii

目的了解鲍曼不动杆菌(A.baumannii,AB)β-内酰胺酶耐药基因表达和传播情况。方法应用PCR技术对我院血液标本分离的17株AB菌进行β-内酰胺酶基因测定,应用K-B法进行抗菌药物敏感性试验。结果17株AB菌有10株为泛耐药株。对头孢菌素类抗生素高度耐药,对哌拉西林/他唑巴坦、亚胺培南及美洛培南等也有较高耐药率,以头孢哌酮/舒巴坦敏感性最高。17株中TEM阳性13株,OXA-23群阳性10株,ADC阳性12株,其余基因均阴性。13株检出β-内酰胺酶基因,10株TEM+OXA-23群+ADC 3种β-内酰胺酶基因阳性。结论我院AB菌不仅具有多重耐药性,而且TEM、OX-A-23群及ADC等β-内酰胺酶基因携带率高。OXA-23群基因的获得和传播与β-内酰胺类药物的滥用有关。

Objective To study on the genes for beta-lactamases expression and spreading in Acinetobacter baumannii. Methods The Kirby-Bauer method were performed to detect the susceptibility of 11 kinds of antimicrobial agents against 17 strains isolated from blood samples. The genotypes of β-lactamases were analyzed by PCR and verificated by DNA sequencing. Results There were 10 multi-drug-resistance strains in 17strains, The resistant rates of 17strains to imipenam, meropenem and piperacillin/tazobactam were high, The sensitivity to cefoperazone / Sulbactam was the highest. In 17 strains of Acinetobacter baumannii TEM genes positive were 13 strains, OXA-23 genes positive were 10 strains, ADC genes positive were 12 strains. The other genes for beta-lactamases were negtive, 10 strains TEM,OXA-23 andADC genes were all positive. Conclusions There are not only muhi-drug-resistance but also high percentages of beta-lactamases genes （TEM, OXA-23 ADC etc.） in A. baumannii isolated from blood sample. OXA-23 genes for beta-lactamases procuring and spreading will be concerned with abuse β-lactama antimicrobial agents.