克雷伯菌β-内酰胺酶、超广谱β-内酰胺酶检测与临床应用

Determination of β- lactamase and extended spectrum β-lactamase in Klebsiella and its preliminary clinical application

目的 探讨克雷伯菌对 β 内酰胺抗生素的耐药性与其产生的 β 内酰胺酶、ESBL的关系。 方法 采用琼脂稀释法、淀粉 碘法、酸测量法及Etest法 ,对本院感染标本中分离的 47株克雷伯菌分别进行了对 β 内酰胺抗生素的最低抑菌浓度 (MIC)、β 内酰胺酶 (青霉素酶和头孢菌素酶 )和超广谱 β 内酰胺酶 (ESBL)检测。 结果 47株克雷伯菌中 2 7株产 β 内酰胺酶 (5 7.4% ) ,其中产青霉素酶 18株 (38.3% )、头孢菌素酶 2 0株 (4 2 .5 % )。ESBL发生率为 19.1%。产两种酶组和ESBL阳性组对 12种β 内酰胺抗生素中的 9种均呈现多重耐药 ,其耐药率介于2 7.3 %～ 10 0 %和 33.3 %～ 10 0 % ;而多数仅产 1种酶或不产酶组、非ESBL株仅对氨苄西林、羧苄西林和头孢唑林耐药 ,其耐药率分别介于 2 7.7%～ 83.3%和 31.6 %～ 94.7%。亚胺培南、头孢他啶和头孢哌酮 /舒巴坦的耐药率为 0 ,除氨苄西林、羧苄西林和头孢唑林外 ,其他 9种抗生素对非ESBL菌株的耐药率 <6 %。结论 常规检测β 内酰胺酶和ESBL ,对指导临床合理选用抗生素。

OBJECTIVE To investigate the relationship between β lactam antibiotic resistant Klebsiella spp and its production of β lactamase and extended spectrum β lactamase(ESBL).METHODS A total of 47 isolates of Klebsiella spp were collected from infectious samples in Xinle Municipal Hospital during January 1997 June 1998. The minimal inhibitory concentration (MIC) of 12 β lactam antibiotics, and ESBL determination were performed for each of the strains. And the susceptible results between β lactamase positive group and β lactamase negative one,ESBL positive group and ESBL negative one were assayed, respectively. RESULTS Twenty seven of 47 strains were β lactamase positive, the total detection rate was 57.4%, of those, penicillinase, cephalosporinase were 38.3%, 42.5%, respectively. The prevalence of ESBL was 19.7% in 47 strains of Klebsiella. The 2 β lactamases(penicillinase and cephalosporinase) production and ESBL positive strains showed multiresistant to 9 of 12 β lactam antibiotics with rates ranging from 27.3 100%, 33.3 100%, respectively. Only one β lactamase (penicillinase or cephalosporinase) production or non β lactamase and ESBL negative strains were only resistant to ampicillin, carbenicillin and cefazolin with rates ranging from 27.7 83.3%, 31.6 94.7%, respectively. The resistant rates of imipenem, ceftazidime and cefoperazone/sulbactam to ESBL strains were null percent. Except ampicillin, carbenicillin and cefazolin, other 9 β lactam antibiotics to ESBL negative strains were less than 6%. CONCLUSIONS It is necessary to distinguish ESBL positive strain and ESBL negative strain strictly. Dealing with ESBL positive strains should be emphasized.