摩氏摩根菌耐药性和超广谱β-内酰胺酶检测

Antibiotic resistance and detection of extended spectrum β-lactamases in Morganella morganii strains

目的了解摩根摩根菌临床分离株对抗菌药物的体外敏感性和临床分布,研究摩氏摩根菌超广谱β-内酰胺酶基因类型分布。方法用K-B法对67株摩氏摩根菌进行药物敏感性检测;PCR法检测超广谱β-内酰胺酶基因,并对PCR结果进行测序分析。结果摩氏摩根菌株对氨苄西林、头孢唑林、头孢呋辛、氨苄西林/舒巴坦、庆大霉素、呋喃妥因均已产生较高的耐药率;而对环丙沙星、左旋氧氟沙星和第三代头孢菌素的耐药率保持在较低水平;对亚胺培南、美洛培南、头孢西丁100%敏感。基因型分析显示有5株携带CTX-M基因,其中3株摩根摩根菌基因型为CTX-M-14型,2株为CTX-M-15型。结论摩氏摩根菌ESBLs检出率仍较低;5株产超广谱β-内酰胺酶摩氏摩根菌对多种抗菌药物耐药,其基因型为CTX-M-15或者CTX-M-14;需加强对不常见肠杆菌科细菌的耐药监测。

Objective To determine the antibiotic resistance and clinical distribution of Morganella morgani strains isolated from clinical specimens and explore the distribution and genetypes of the pathogen＇ s extended spectrum β-1actamases. Methods A total of 69 strains of Morganella morgani were analysed for their antimicrobial susceptibility. The blagene of ES- BLs producing isolates were detected by PCR and then sequenced. Results None of these Morganella morgani isolates was found resistant to imipenem, mempenem, and cefoxitin. The resistances of Morganella morgani isolates to common antibiotics were higher, but remained lower to fluoroquinolones and the third generation cephalosporins with a resistance range from 4% to 15%. Of the 69 isolates, 5 （7.46%） strains were identified as ESBLs producers. The genotypes of these strains included CTX-M-14 （2/5） and CTX-M-15 （3/5）. Conclusion 5 Morganella morganii strains produce CTX-M-14 or CTX-M-15 ES- BLs, which results in their resistance to most β-lactams. More attention should be paid to the monitoring of resistance of these strains.