【摘要】 目的了解临床分离脑膜炎败血黄杆菌(Chryseobacterium meningosepticum)耐药特性和金属β-内酰胺酶(MBL)产酶率及基因型。方法采用琼脂稀释法检测25株细菌对抗菌药物的最低抑菌浓度(MIC),三纸片增效法、改良三维试验法检测MBL表型;并采用聚合酶链反应(PCR)及序列分析,确定MBL基因型。利用接合试验监测耐药基因的可转移性,等电聚焦电泳(IEF)法测定β-内酰胺酶等电点(pI)。结果25株脑膜炎败血黄杆菌对亚胺培南、美罗培南的耐药率达72.0%,而对利福平和加替沙星、左氧氟沙星的耐药率均低于16.0%。14株细菌检出产MBL,产酶率为56.0%。MBL全编码基因扩增及序列分析显示,14株细菌共检出17个编码MBL的基因,分别为blaB1,2株;blaB2,5株;blaB3,4株;blaB11,4株;blaGOB-1,1株;blaGOB-10,1株。接合试验均为阴性。结论脑膜炎败血黄杆菌具有严重的多重耐药现象,并具有高MBL检出率。MBL基因可能位于脑膜炎败血黄杆菌的染色体上,不能通过细菌质粒等可移动基因元件发生菌株和菌种间传播。更多还原

【Abstract】 Objective To investigate the antibiotical resistance and to understand the phenotype and genotype of metallo-β-lactamasein clinical chryseobacterium meningosepticum. Methods The MIC of 18 antibiotics to 25 chryseobacterium meningosepticum strains were detected by agar dilution method. Phenotype of metallo-β-lactamase was detected by three-disc synergy test and modified three dimension test. Polymerase chain reaction(PCR)amplification with some prime sets for metallo-β-lactamase gene was conducted for all isolates,and then the DNA sequence analysis was conducted for the amplified which were positive for metallo-β-lactamase identified in genotype analysis. Conjugation experiment was used to study the transmission of metallo-β-lactamase encoding gene. pI of β-lactamase was measured by isoelectric focusing assay.Results The antibiotical resistance of 25 chryseobacterium meningosepticum to imipenem,meropenem was 72.0% respectively. However, gatifloxacin, levofloxacin and rifampin had better antimicrobiotial ability to chryseobacterium meningosepticum compared with other antibiotics in MIC. 14 strains were identified to produce metallo-β-lactamase using phenotype test and PCR amplification simultaneously. 14 strains were detected to have metallo-β-lactamase genotype by PCR amplification using prime sets of complete coding gene,including 15 blaB and 2 blaGOB. The numbers of blaB, blaB2, blaB3,blaB11,blaGOB-1 and blaGOB-10 were 2,5,4,4,1 and 1 respectively.Conjugation experiment showed that metallo-β-lactamase encoding gene could not transfer. Conclusions Chryseobacterium meningosepticum have high multi-drug resistance and high rate of metallo-β-lactamase producing,and thus it is difficult to therapy. The gene of metallo-β-lactamase locate on chromosome of Chryseobacterium meningosepticum and cannot be transferred horizontally.更多还原