栖冷克吕沃尔菌耐药性及β-内酰胺酶检测

Antimicrobial Susceptibility and Classification of β-Lactamases Produced by Kluyvera cryocrescens

目的研究栖冷克吕沃尔菌的耐药性及其所产各种β-内酰胺酶(β-lase)分布情况。方法采用琼脂扩散法分析17株该菌的耐药性,采用多底物纸片法(协同法、拮抗法)、产超广谱β-内酰胺酶(ESBLs)确认试验、AmpC酶检测法检测其所产各种β-lase。结果对AMP、GEN、CFZ和磺胺类抗菌药物的耐药率分别为100.0%、88.2%、88.2%、88.2%,对IMP、CIP和AMK的耐药率分别为0.0%、35.3%、47.1%;17株嗜冷克鲁依弗菌各种β-lase总检出率为100.0%,其中单独产青霉素酶、广谱酶、ESBLs分别为2株(11.8%)、6株(35.3%)、9株(52.9%),产AmpC酶总数1株,未检出碳青酶烯酶;持续高产AmpC酶+ESBLs复合酶1株。结论嗜冷克鲁依弗菌耐药性严重,均为多重耐药菌;对AMP、GEN、CFZ和磺胺类抗菌药物的耐药率很高,对IMP、CIP和AMK较为敏感;本组菌产β-lase率很高,产4种酶有5种方式,以广谱酶、ESBLs为主,未检出碳青酶烯酶。

OBJECTIVE To study the antimicrobial susceptibility, classification and distribution of the β-lactamases produced by Kluyvera cryocrescens. METHODS To detect the β-lactamases produced by 17 strains of K. cryocrescens with a multi-disk test [synergy test, and antagonized test for the inducible AmpC β-lactamases （IABLs）], AmpC β-lactamases （ABLs） phenotype test and extended-spectrum β-lactamases（ESBLs） confirment test, and the susceptibility of antimicrobial agents. RESULTS The resistant rate to AMP, GEN, CFZ and SXT was 100.0%, 88.2%, 88.2% and 88.2%, respectively, and that to IMP, CIP and AMK was 0.0%, 35.3%, and 47.1%, respectively; all of 17 strains produced the β -lactamases（100.0%）, two strains produced penicillinases（11. 8%）, six strains produced broad-spectrum β-lactamases（35.3%） and nine strains produced ESBLs （52.9%）, 1 strain produced ABLs, and 1 strain produced ESBLs＋high product ABLs, all did not produce carbapenem-hydrolyzing β-lactamases（CHBLs）. CONCLUSIONS The resistant rate of K. cryocrescens is very high, all multi-resistant. The resistant rate of K. cryocrescens to AMP, GEN, CFZ and SXT is high, but to IMP, CIP and AMK is lower. The rate of β-1actamases produced by the 17 strains of K. cryocrescens is very high, four classes of β-lactamases are produced by five types, mainly BSBLs and ESBLs, without CHBLs.