阴沟肠杆菌超广谱β-内酰胺酶、诱导酶的检出与耐药相关性的分析

Correlative analysis of detected extended -spectrum beta -lactamase and in-ducibleβ-lactamase in Enterobacter cloacae and drug resistance.

目的了解阴沟肠杆菌超广谱β-内酰胺酶和诱导酶的产生和分布情况,并分析产酶特性和耐药表型的相关性。方法用纸片扩散确证法和相邻纸片法对104株阴沟肠杆菌进行超广谱β-内酰胺酶及诱导酶的检测,用VITEK全自动药敏分析系统和K-B琼脂扩散法检测其对20种抗生素的耐药性。结果104株阴沟肠杆菌中,检出超广谱β-内酰胺酶阳性株77株,占74%,诱导酶阳性株26株,占25%,13株两种酶同时阳性。超广谱β-内酰胺酶阳性株主要集中在几个病区,诱导酶阳性株则无此倾向,104株菌对多种抗生素高度耐药,产超广谱β-内酰胺酶株的耐药率明显高于非产酶株,产诱导酶株的耐药率反而低于非产酶株。结论阴沟肠杆菌产酶情况和耐药性均十分严重。多重耐药的主要原因是由于菌株产生超广谱β-内酰胺酶,产酶株对三代头孢的体外敏感试验不能正确反映临床的治疗效果。实验室应加强阴沟肠杆菌产酶情况的检测,治疗产酶阴沟肠杆菌引起的感染,首选亚胺培南,其次为舒普深,任何情况下应避免使用三代头孢。

Objective To study the production and distribution of extended-spec-trumβ-lactamase and inducibleβ-lactamase in Enterobacter cloacae,and to investigate their relation to drug resistance.Methods The determination of ESBLs and inducibleβ-lactamase in Enterobacter cloacae were performed by disc diffusion confirmatory test and double-disc diffusion test.Drug-resistance was detected using GNS-506susceptibil-ity card of Vitek60system and disc diffusion test.Results Among104strains of En-terobacter cloacae,there were77strains producing ESBLs bacteria,accounted for74%,26strains producing inducibleβ-lactamase bacteria,accounted for25%,13strains pro-ducing both two ESBLs producing strains were fastened on certain clinical wards,but inducibleβ-lactamase strains producing without this tendency.Multi-cross resistance a-gainst antibiotics were high in the104isolates,ESBLs producing strains were more re-sistant to antibiotics than ESBLs negative strains.Inducibleβ-lactarnase producing strains had lower resistance than inducibleβ-lactamase negative strains.Conclu sions The condition of Enterobacter cloacae in producing ESBLs and inducibleβ-lactamase and its drug resistance is very serious.The chief reason of high drug-resistance is the ESBLs produced by the strains.It's important for the laboratory to detect the characteristics ofβ-lactamase produced by Entreobacter cloacae.To deal withβ-lactamase-producing strains,imipenem is of the first choice,then sulperazon/sulbactam,in any circumstance the third generation cephalosporin should be avoided.