McColm A A, Sowa M A, Ryan D M
J Antimicrob Chemother. 1984 May;13(5):437-45. doi: 10.1093/jac/13.5.437.
In an infant rat model of Haemophilus influenzae, type b meningitis, where treatment was given 24 and 48 h after infection, the dose of ceftazidime required to eradicate the infection from the CSF of half the animals (CD50) ranged from less than 0.15-1.5 mg/kg/dose. The accompanying blood infections were marginally less responsive to therapy with CD50 values ranging from 0.5-3.9 mg/kg/dose. Comparable data for ampicillin were 12.5-40 mg/kg/dose and 20- greater than 200 mg/kg/dose for the CSF and blood infections while those for chloramphenicol were 18- greater than 100 mg/kg/dose and 22- greater than 100 mg/kg/dose for the CSF and blood infections respectively. Investigation of the relative rates of kill in vivo showed that all three drugs rapidly reduced the bacterial numbers to minimal levels. However, whereas ceftazidime completely eradicated the infection, chloramphenicol, and to a lesser extent, ampicillin-treated rats experienced substantial relapsing. Ceftazidime penetrated into the CSF of infected and uninfected rats slightly better than ampicillin--7.3% compared to 4.0% of the corresponding blood levels respectively. These results indicate that ceftazidime is significantly more active in the infant rat model of H. influenzae, type b meningitis than ampicillin or chloramphenicol.
在b型流感嗜血杆菌脑膜炎的幼鼠模型中，感染后24小时和48小时给予治疗，半数动物脑脊液中根除感染所需的头孢他啶剂量（CD50）为每剂量0.15-1.5毫克/千克。伴随的血液感染对治疗的反应略低，CD50值为每剂量0.5-3.9毫克/千克。氨苄西林在脑脊液和血液感染中的可比数据分别为每剂量12.5-40毫克/千克和20-大于200毫克/千克，而氯霉素在脑脊液和血液感染中的可比数据分别为每剂量18-大于100毫克/千克和22-大于100毫克/千克。体内相对杀灭率的研究表明，所有三种药物都能迅速将细菌数量降至最低水平。然而，虽然头孢他啶能完全根除感染，但氯霉素以及在较小程度上接受氨苄西林治疗的大鼠出现了大量复发。头孢他啶渗透到感染和未感染大鼠脑脊液中的能力略优于氨苄西林，分别为相应血药浓度的7.3%和4.0%。这些结果表明，在b型流感嗜血杆菌脑膜炎的幼鼠模型中，头孢他啶比氨苄西林或氯霉素的活性显著更高。
