Shungu D L, Weinberg E, Cerami A T
J Clin Microbiol. 1985 Jun;21(6):875-9. doi: 10.1128/jcm.21.6.875-879.1985.
Imipenem is a member of a new class of highly potent beta-lactam antibiotics, carbapenems, with an antibacterial spectrum that includes nearly all currently known aerobic and anaerobic bacterial species of clinical significance. Although relatively stable in most standard laboratory media used for antimicrobial susceptibility testing, imipenem undergoes rapid inactivation in thioglycolate broth, a recommended medium for susceptibility testing of anaerobic bacteria by the broth disk method. In the current study, a panel of 36 anaerobic bacteria consisting of 28 clinical isolates and eight quality control strains was used to determine the suitability and accuracy of the broth disk methods with brain heart infusion, Schaedler, and anaerobic broths, in comparison to the reference agar dilution method, for the anaerobic susceptibility testing of imipenem. To achieve single test concentrations of approximately 8, 16, and 64 micrograms/ml for imipenem, cefoxitin, and piperacillin, respectively, which correspond to the MIC breakpoints of the test drugs, four 10-microgram imipenem disks, three 30-microgram cefoxitin disks, and three 100-microgram piperacillin disks were used in 5 ml of broth. The correlation between the reference agar dilution method and each of the three broth disk elution procedures evaluated was excellent, for imipenem (100% agreement) and somewhat less so for cefoxitin and piperacillin. Therefore, brain heart infusion, Schaedler, and anaerobic broths, but not thioglycolate broth, are suitable for anaerobic susceptibility testing of imipenem by the disk elution method.
亚胺培南是一类新型高效β-内酰胺抗生素——碳青霉烯类抗生素的成员，其抗菌谱几乎涵盖了目前所有已知的具有临床意义的需氧和厌氧细菌种类。尽管亚胺培南在用于抗菌药敏试验的大多数标准实验室培养基中相对稳定，但在硫乙醇酸盐肉汤（一种推荐用于肉汤纸片法检测厌氧菌药敏性的培养基）中会迅速失活。在本研究中，使用了一组由28株临床分离株和8株质量控制菌株组成的36株厌氧菌，来确定脑心浸液、 Schaedler肉汤和厌氧肉汤的肉汤纸片法与参考琼脂稀释法相比，对亚胺培南进行厌氧菌药敏试验的适用性和准确性。为了分别使亚胺培南、头孢西丁和哌拉西林的单次试验浓度达到约8、16和64微克/毫升，这与受试药物的最低抑菌浓度（MIC）断点相对应，在5毫升肉汤中使用了4片10微克的亚胺培南纸片、3片30微克的头孢西丁纸片和3片100微克的哌拉西林纸片。对于亚胺培南，参考琼脂稀释法与所评估的三种肉汤纸片洗脱程序中的每一种之间的相关性都非常好（一致性为100%），而对于头孢西丁和哌拉西林则稍差一些。因此，脑心浸液、 Schaedler肉汤和厌氧肉汤，但不包括硫乙醇酸盐肉汤，适用于通过纸片洗脱法对亚胺培南进行厌氧菌药敏试验。
