摘要
目的 :了解肠杆菌属细菌中超广谱 β内酰胺酶 (ESBLs)和AmpC酶的发生率及其对耐药性的影响。 方法 :以聚合酶链反应 (PCR)方法检测肠杆菌属细菌中ESBLs和AmpC酶基因为金标准 ,评价三维试验法检测ESBLs和AmpC酶的灵敏度和特异性 ;用K B(Kirby bauer)法测定肠杆菌属细菌对 13种抗菌药物的敏感性。 结果 :在 2 0 0 2年 6月— 2 0 0 3年 5月我院临床分离的 73株肠杆菌属细菌中 ,4株 (5 .5 % )单产AmpC酶 ,15株 (2 0 .5 % )单产ESBLs,38株 (5 2 .1% )产ESBLs +AmpC酶 ,16株 (2 1.9% )为不产酶菌株。肠杆菌属细菌AmpC酶的检出率为 5 7.5 % (4 2 / 73) ;而ESBLs的检出率则为 72 .6 % (5 3/ 73)。与PCR方法相比 ,三维试验法检测ESBLs的灵敏度和特异度分别为 92 .6 % (5 0 / 5 4 )、10 0 .0 % (19/ 19) ;三维试验法检测AmpC酶的灵敏度和特异度分别为 76 .2 % (32 / 4 2 )、87.1% (2 7/ 34) ,两者与PCR方法的符合率分别为 94 .5 % (6 9/ 73)和 80 .8% (5 9/73) ,两种方法所获得的结果经统计学方法进行处理 ,χ2 值分别为 2 .2 5和 1.78(P值均 >0 .0 5 )。药敏试验结果显示非ESBLs产生株对大多数抗菌药物敏感 ,但产酶株耐药程度均较高 ;产ESBLs+AmpC菌株对多种抗菌药物的耐药率均较单产ESBLs菌株高。结论
Objective: To investigate the prevalence of ESBLs and AmpC β-lactamases in Enterobacter spp. and its impact on bacterial resistance. Methods:The sensitivity and specificity of three-dimensional test for the detection of ESBLs and AmpC β-lactamases were evaluated. Susceptibility of Enterobacter spp. strains to 13 antimicrobial agents was determined by K-B (Kirby-Bauer) method. Results:Among 73 strains of Enterobacter spp. isolated in Huashan hospital from June 2002 to May 2003, 4 strains (5.5%) produced AmpC β-lactamases and 15(20.5%) produced ESBLs, 38(52.1%) produced both ESBLs and AmpC β-lactamases, no β-lactamases were detected in the remaining 16 strains. Totally, AmpC β-lactamases were detected in 57.5%(42/73) of Enterobacter spp. strains, and ESBLs were detected in 72.6%(53/73) of the strains. The sensitivity and specificity of three-dimensional test were 92.6%(50/54) and 100.0%(19/19) respectively in detection of ESBLs being 76.2%(32/42) and 87.1%(27/34) in detection of AmpC, respectively. The coincidence rates in detectiing ESBLs and AmpC β-lactamases between three-dimensional test and PCR method were 94.5%(69/73) and 80.8%(59/73) respectively. No statistically significant difference existed between the two methods (P>0.05). Results of susceptibility testing showed that ESBLs-negative strains were susceptible to most antimicrobial agents, however strains producing ESBLs- or AmpC or both were highly resistant. Conclusions:The percentage of ESBLs and AmpC β-lactamases producing strains in Enterobacter spp. were high. Three-dimensional test has the merit of easy to operate so is especially suitable for the detection of both ESBLs and AmpC β-lactamases producing clinical isolates .
出处
《中国抗感染化疗杂志》
2004年第5期283-286,共4页
Chinese Journal of Infection and Chemotherapy
关键词
超广谱Β内酰胺酶
三维试验
Extended-spectrum β-lactamase
Three-dimensional test
