摘要
以金黄色葡萄球菌ATCC25923作为质控菌,用微量稀释法测定了7种药物对临床分离猪链球菌的体外最小抑菌浓度(MIC),以临床检验标准委员会(CLSI)的临界浓度作为判断标准,判定了猪链球菌对7种药物的耐药性;并分别在外排泵抑制剂氰氯苯腙(CCCP)、利血平存在的情况下,测定红霉素、泰乐菌素对分离菌MIC的影响。微量稀释法测定的MIC结果显示:临床分离的菌株以耐药菌为主,耐药谱型达11种;对磺胺间甲氧嘧啶(100%)耐药性最为严重,对红霉素(39.5%)、泰乐菌素(31.6%)、恩诺沙星(28.9%)、环丙沙星(28.9%)耐药性次之,而氟苯尼考和氨苄西林对所选菌株均敏感。在外排泵抑制剂存在时,抗菌药物对部分分离的耐药菌MIC下降,提示猪链球菌存在与抗菌药物耐药相关的主动外排机制。以上结果提示,国内分离的猪链球菌对临床常用的药物产生一定的耐药性,在临床选用药物进行治疗时,应充分考虑菌株的耐药性问题,以免延误病情造成治疗失败。
A number of 38 strains were surveyed for minimal inhibitory concentration （MIC） in vitro to 7 drugs by microdilution test to find out the resistance present situation among Streptococcus suis isolated from clinic. Staphylococcus aureus ATCC25923 was used as reference strain for MIC quality control. Clinical categorization of isolates as susceptible or resistant was based on MIC interpretative standards of the Clinical Laboratory Standards Institute （CLSI）. Carbonylcyanide - p - chlorophenyl hydrazone （CCCP） and reserpine was used respectively to determine the effect of efflux pump inhibitor on the MIC of erythromycin and tylosin against Streptococcus suis resistant isolates. The result of MIC tested by microdilution indicated that none of the strains were susceptible to all antimicrobial compounds tested and eleven resistant patterns were detected. Resistance to sulfamonomethoxine （100%） was most frequent, and then erythromycin （39.5%）, tylosin （31.6%）, enrofloxacin （28.9%）, ciprofloxacin （28.9%）, while 100% strains were susceptible to florfenicol and ampicillin. The MICs of erythromycin and tylosin against some resistant strains were decreased to different degree when efflux pump inhibitor was used suggesting that the active efflux pumps inducing resistance to antimicrobial agents become much stronger in Streptococcus suis resistant strains. This study demonstrated a significant increase in resistance to most commonly used antimicrobial agents among Streptococcus suis strains isolated from clinic and the resistant sensitivity must be paid attention to in the clinic.
出处
《安徽科技学院学报》
2009年第2期11-16,共6页
Journal of Anhui Science and Technology University
关键词
猪链球菌
微量稀释法
体外最小抑菌浓度
耐药性
外排泵抑制剂
Streptococcus suis isolates
Microdilution test
In vitro MIC
Drug resistance
Efflux pump inhibitor
