不动杆菌β-内酰胺酶的分类和分布研究

Study on the classification and distribution of the β-lactamases produced by Acinetobacter

目的 了解不动杆菌所产各种 β 内酰胺酶 (β lactamases)分布情况。 方法 采用多底物纸片协同法、ESBLs确认试验、纸片拮抗法、AmpC酶检测法检测 4 2株不动杆菌所产各种 β 内酰胺酶。 结果 4 2株不动杆菌总β 内酰胺酶检出率为10 0 % ,其中产头孢菌素酶 2株 (4.8% )、诱导型AmpC酶 5株 (11.9% )、单独产AmpC酶及ESBLs各 7株 (16 .7% ) ,产AmpC酶及ESBLs 2 1株 (5 0 .0 % ) ,未检出单独青霉素酶、广谱酶和碳青霉烯酶 ;2 8株产ESBLs菌株中 ,纸片协同法阳性仅 7株 ,占 2 5 .0 % (7/ 2 8) ,ESBLs确认试验阳性 2 6株 ,2 1株产ESBLs菌株的超广谱β 内酰胺抗生素抑菌环直径为6mm。结论 本组不动杆菌产 β 内酰胺酶总检出率很高 ,以AmpC酶、ESBLs为主 ,未检出青霉素酶和碳青霉烯酶 ;本组不动杆菌所产 β

Objective To study the classification and distribution of the β lactamases produced by Acinetobacter. Methods The β lactamases produced by 42 strains of Acinetobacter were detected with a multi disk synergy test, inducible test, AmpC β lactamases phenotype test and extented spectrum β lactamases(ESBLs) confirmatory test. Results All strains ( 100% ) produced the β lactamases, 2 strains ( 4.8% ) produced cephalosporinases, 5 strains ( 11.9% ) produced inducible AmpC β lactamases, 7 strains ( 16.7% ) produced ESBLs or AmpC β lactamases respectively, 21 strains ( 50.0% ) produced both ESBLs and AmpC β lactamases. None produced penicillinases, broad spectrum β lactamases and carbapenem hydrolyzing β lactamases. Among 28 strains producing ESBLs, 7 strains were synergy test positive, 26 strains were ESBLs confirmatory test positive. Conclusion The detecting rate of β lactamases produced by 42 strains of Acinetobacter were very high, the majority were AmpC β lactamases and ESBLs, all did not produce penicillinases, broad spectrum β lactamases and carbapenem hydrolyzing β lactamases. The product of ESBLs produced by 42 strains was high.