Bingen E, Lambert-Zechovsky N, Guihaire E, Mancy C, Aujard Y, Mathieu H
Pathol Biol (Paris). 1986 May;34(5):530-3.
Morbidity and mortality among neonates with group B streptococcal infections remain high. As delays in bacterial killing may be responsible for these poor results, there is a need for studies into killing kinetics. We investigated antimicrobial sensitivity and killing effect time lags for penicillin, ampicillin and mezlocillin, alone and in combination with gentamicin or amikacin, against 20 strains of group B streptococci isolated in cultures of blood and cerebrospinal fluid from neonates. A culture of each strain (10(5) germs/ml) was exposed to the antibiotics individually or in combination. Antibiotics were used in the concentrations achieved clinically. Surviving bacteria were counted after 2 h 30, 4 h 30 and 24 h. incubation. Mean killing curves showed that the time interval until onset of a killing effect was 24 hours with either penicillin or ampicillin alone, against 4 h 30 with penicillin-amikacin or ampicillin-gentamicin. The most rapid killing effect (2 h 30) was observed with mezlocillin alone and ampicillin-amikacin. No antagonism was found between mezlocillin and aminoglycosides. Choice of the best antibiotic treatment for group B streptococcal infections should be based on both the rapidity of the in vitro killing effect and the antibiotic's diffusion into the site of the infection.
B族链球菌感染的新生儿发病率和死亡率仍然很高。由于细菌杀灭延迟可能是导致这些不良结果的原因，因此有必要研究杀灭动力学。我们研究了青霉素、氨苄西林和美洛西林单独使用以及与庆大霉素或阿米卡星联合使用时对从新生儿血液和脑脊液培养物中分离出的20株B族链球菌的抗菌敏感性和杀灭效应时间滞后情况。将每种菌株的培养物（10⁵个细菌/毫升）分别或联合暴露于抗生素。抗生素使用临床达到的浓度。在孵育2小时30分钟、4小时30分钟和24小时后对存活细菌进行计数。平均杀灭曲线显示，单独使用青霉素或氨苄西林时，直至出现杀灭效应的时间间隔为24小时，而青霉素-阿米卡星或氨苄西林-庆大霉素联合使用时为4小时30分钟。单独使用美洛西林和氨苄西林-阿米卡星时观察到最快的杀灭效应（2小时30分钟）。美洛西林和氨基糖苷类之间未发现拮抗作用。对于B族链球菌感染，最佳抗生素治疗的选择应基于体外杀灭效应的快速性以及抗生素向感染部位的扩散情况。
