大肠埃希菌产β-内酰胺酶类型的动态比较研究

β-Lactamases Produced by Escherichia coli: Recent Years Study on Their Classification and Distribution

目的动态比较研究大肠埃希菌(E.coli)所产各种β-内酰胺酶(β-lase)的分布。方法 采用多底物改良 相邻纸片法检测195株,其中S1期75株、S2期60株和S3期60株;E.coli所产各种β-lase。结果 S1期E.coli 总β-lase检出率为70.67％,其中产青霉素酶18株(24.00％),产广谱酶8株(10.67％),产ESBLs 27株 (36.00％),未检出其他β-lase;S2期E.coli总β-lase检出率为81.67％,其中产青霉素酶5株(8.33％),产广谱酶 17株(28.33％),产ESBLs27株(45.00％),未检出其他β-lase;S3期E.coli总β-lase检出率为91.00％,其中产青 霉素酶3株(5.OO％),AmpC酶1株(1.67％),广谱酶10株(16.67％),产ESBLs29株(48.33％),同时产ESBLs+ AmpC酶株8株(13.33％),酶抑制剂耐药的β-内酰胺酶4株(6.00％,1株IRT、1株IRBSBLs、2株IRESBLs),未 检出碳青酶烯酶。结论本组E.coli所产各种β-lase的总产酶率、β-lase类型数均随时间而提高。

OBJECTIVE To study the classification and distribution of the β-lactamases produced by Escherichia coli in recent years. METHODS To detect the β-lactamases produced by 195 strains of E. coli (S1 , S2 and S3) with a multi-disk synergy test. RESULTS In the S1 , the total positive rate was 70. 67%, 18 strains produced penicillina-ses (10.67%), 8 strains produced broad-spectrum (β-lactamases (BSBLS, 10. 5%); and 7 strains produced extended-spectrum fi-lactamases (ESBLs, 36. 00%), no other β-lactamases were detected. The total positive rate in the Sz was 81. 67%, 5 strains produced penicillinases (8. 33%), 17 strains produced BSBLs (28. 33%); and 27 strains produced ESBLs (45. 00%) , no other β-lactamases were detected. In the S3 , the total detected rate was 91. 00% , 3 strains produced penicillinases (5. 00%) , 1 strain produced AmpC (3-lactamases (1. 67%) , 10 strains produced BSBLs (16. 67%); 29 strains produced ESBLs (48. 33%) , 8 strains produced ESBLs+AmpC β-lacta-mases (13. 33%) , and 4 strains produced inhibitor-resistant β-lactamases (6. 00% , 1 IRTs, 1 IRBSBLs, 2 IRES-BLs) , no carbapenem-hydrolyzing β-lactamases were detected. CONCLUSIONS The total detected rate and type of fi-lactamases produced by E. coli in recent years (S1 , S2 and S3) is raising as the time going on.