INOCULUM EFFECT OF BETA-LACTAM ANTIBIOTICS ON ENTEROBACTERIACEAE
INOCULUM EFFECT OF BETA-LACTAM ANTIBIOTICS ON ENTEROBACTERIACEAE
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DOI：
10.1128/aac.28.5.601
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发表时间：
1985-01-01
影响因子：
4.9
通讯作者：
BUCCINI, F
中科院分区：
文献类型：
--
作者：
ENG, RHK;CHERUBIN, C;BUCCINI, F
研究了七种β-内酰胺抗生素的抗菌活性以及它们对大肠杆菌、肺炎克雷伯菌和鼠伤寒沙门氏菌产生接种效果的程度。氨曲南、头孢哌酮、头孢他啶杀菌力差，引起明显的菌丝化，对大肠杆菌、肺炎克雷伯菌、鼠伤寒沙门氏菌有较大的接种效果。头孢噻肟和头孢曲松具有更快速的杀菌作用，仅产生中等量的丝状形式，并表现出适度的接种效果，而头孢西丁和亚胺培南均具有快速杀菌作用，并且仅表现出最小至无接种效果。接种效果与细菌培养期间的药物稳定性不相关。对肠杆菌科这些物种的接种效应似乎是光密度增加的表现，继发于丝状细菌形式的发展，并且在暴露于不快速杀菌的抗生素期间细菌量增加。当使用浊度作为确定细菌生长存在的参数时，这些观察结果对于 β-内酰胺抗生素的药敏测试具有明显的意义。
Seven .beta.-lactam antibiotics were studied for both their antimicrobial activity and the degree to which they produced inoculum effect on Escherichia coli, Klebsiella pneumoniae, and Salmonella typhimurium. Aztreonam, cefoperazone, and ceftazidime were poorly bactericidal, caused marked bacterial filamentation, and exhibited a large inoculum effect on E. coli, K. pneumoniae, and S. typhimurium. Cefotaxime and ceftriaxone were more rapidly bactericidal, caused only a moderate amount of filamentous forms, and exhibited a modest inoculum effect, while cefoxitin and imipenem both were rapidly bactericidal and exhibited only a minimal-to-noinoculum effect. The inoculum effect did not correlate with drug stability during incubation with the bacteria. Inoculum effect on these species of the family Enterobacteriaceae appears to be a manifestation of increase in optical density secondary to the development of filamentous bacterial forms with an increase in bacterial mass during exposure to antibiotics which are not rapidly bactericidal. These observations have a clear significance for the susceptibility testing of beta-lactam antibiotics when turbidity is used as a parameter to determine presence of bacterial growth.