β-内酰胺类药物对临床分离猪链球菌2型的体外抗菌活性

Anitimicrobial susceptibility in vitro of 10 β-lactam drugs against pig Streptococcus suis type 2 isolates in China

采用微量稀释法测定了32种药物对临床分离猪链球菌的体外最小抑菌浓度（MIC），以美国临床检验标准委员会（NCCLS）的临界浓度做为判断标准，判定了猪链球菌2型对10种β-内酰胺类药物的耐药性。结果表明，临床分离的菌株以耐药菌为主，头孢他定（CTD）、头抱噻吩（CFT）、头抱曲松（CRX）、阿莫西林／舒巴坦钠（AMO／SUL）对猪链球菌2型的耐药率最高，达100%；其次为青霉素G（PEN）、苯唑西林（OCL）、哌拉西林钠（PPC），达90％以上，只有头孢噻肟（CTX）有微弱的抗菌活性，其耐药率也达82．6%。MIC50 0．5～32mg／L，MIC90 2～256mg／L。猪链球菌2型对辟内酰胺类药物耐药性已十分严重，应引起足够重视。

A number of 23 Streptococcus species isolated from diseased pigs were surveyed for in vitro minimal inhibitory coneentration（MIC） to 10 drugs by mierodilution test. Clinical categorization of isolates as susceptible or resistant was based on MIC interpretative standards of the National Committee for Clinical Laboratory Standards （NCCLS） ,most strains were multidrug-resistant. Resistance to ceftazidime,eefalotine,ceftriaxone and amoxicillin/ sulbactam were very high,their resistant rates being 100 %. Resistant rates to penicillin G,Oxaeillin,piperaeillin exceeded 90 %. Only cefotaxime had small antimicrobial activity,its resistant rate achieved 82.6 % ,too. MIC50 was between 0. 5 mg/L and 32 mg/L. MIC50 was between 2 mg/L and 256 mg/L. β- lactam drug resistance to Streptococcus suis type 2 has been very prominant and should pay more attention to.