摘要
为比较鸡源大肠杆菌培养时间对药敏试验结果的影响,采用12×8型微孔反应板进行2倍稀释法测定鸡源大肠杆菌X1(临床分离敏感菌)、鸡源大肠杆菌C2(临床分离的产β-内酰胺耐药菌株)和大肠埃希氏菌ATCC25922菌株对恩诺沙星、阿莫西林/克拉维酸(4/1)、多西环素和阿米卡星的敏感性。微孔板置于37℃恒温箱中培养,并分别在培养2～22 h各记录一次最小抑菌浓度(MIC)值。结果显示:阿莫西林/克拉维酸、恩诺沙星、阿米卡星和多西环素的MIC值在14～22 h均无变化。当培养时间在4～14 h时,不同药物的MIC值增大幅度不一样,其中阿莫西林/克拉维酸(4/1)和恩诺沙星的MIC值变化不明显,而阿米卡星、多西环素的MIC值变化较大;同时,相同药物对不同菌株的MIC值变化幅度也不一样,其中标准菌株MIC值变化最小,最多不超过8倍,产酶菌株(C2)结果变化较大,最大达到1 024倍,最小8倍。综上所述,临床中进行药敏试验过程中,药物的MIC值随细菌的培养时间延长而增大,当培养时间超过14 h时,其MIC值随细菌的培养时间延长而不再出现明显变化,即在时间有限的情况下,药敏试验至少应培养14 h才能得出较合理的、能正确指导临床用药的MIC值。
To compare the influence of cultural time of Escherichia coli strains derived form chicken on the results of antibiotic susceptibility test, the minimum inhibitory concentrations （MICs） of amoxicillin/clavulanic acid （4/1）, deoxycycline, enrofloxacin and amikacin were detected with the doubling dilution method in 12 x 8 microtitre reaction plate and cultured at 37 ~C against E. coli Xlstrain （susceptibility strain isolated from farm）, E. coli C2 strain （produced beta-lactam drug-resistant strain isolated from farm）, and E. coli ATCC25922 strain, at the culture time of 2 h, 4 h, 6 h, 8 h, 10 h, 12 h, 14 h, 16 h, 18 h, 20 h, 22 h and 22 h. The results revealed that the MICs of these drugs showed little changes at different incubation times （from 14 to 22 hours）. But the MICs of the drugs increased when theculture time was extended from 4 to 14 hours, and the MICs of different drugs had different increasing values. The MICs of amoxicillin/clavulanic acid （4/1） and enrofloxacin had no significance change, while the MICs of amikacin and doxycycline had a distinct change. At the same time, the same drug against different strains had different MICs. The MIC of the E. coli ATCC25922 strain has the minimal value, not more than eight times, but the result of zymogenic strain（C2） had a remarkable change, the biggest one being 1 024 times, and the least one eight times. In summary, the MICs of drugs increased with prolonged cultural time during drug sensitivity test in clinical trial. The MICs had no obvious change with prolonged cultural time when cultural time was more than 14 hours, namely, the cultural time should be at least 14 hours to get a reasonable and practical MICs under limited cultural time.
出处
《实验室研究与探索》
CAS
北大核心
2012年第7期23-26,180,共5页
Research and Exploration In Laboratory
基金
河南省科技攻关重点项目(102102110034)
