青霉素与头孢曲松联用对肺炎链球菌体外抗菌效果研究

目的研究青霉素与头孢曲松钠对肺炎链球菌的联合抗菌效应。方法应用E-test法测定青霉素的最低抑菌浓度（MIC）;采用棋盘稀释法,测定青霉素与头孢曲松联用对肺炎链球菌的体外抑菌效果,计算FIC指数。结果青霉素钠与头孢曲松联合应用后对中介及耐药菌株,其MIC明显减低,FIC≤0.5占15.4%;0.5〈FIC≤1占84.6%;1〈FIC≤2和FIC〉2为0。对敏感菌则其MIC有不同程度的升高,FIC≤0.5和0.5〈FIC≤1占0;1〈FIC≤2占14.3%;FIC〉2占85.7%。结论青霉素钠与头孢曲松联合应用对耐药及中介的肺炎链球菌以相加作用为主,而对敏感菌株则以拮抗作用为主。

Antibacterial Activity of Penicillinin Combination with Ceftriaxone Against Streptococcus Pneumoniain in Vitro

Objective To investigate antibacterial activity of penicillinin combination with ceftriaxone against streptococcus pneumoniain in vitro. Methods The MIC values of penicillin were determined by E-test. The checkerboard method was used to determine the combinations activity against these strains. Results The MIC was reduced significantly for the combination of penicillinin and ceftriaxone against penicillin resistant streptococcus pneumonia（ PRSP） and penicillin international susceptible streptococcus pneumonia（ PISP）. The FIC≤0. 5 accounted for15. 4%,0. 5〈FIC≤1 accounted for 84. 6%,1〈FIC≤2 and FIC〉2 accounted for 0%. The MIC was partly increased for the combination of two antibiotics against penicillin sensitive streptococcus pneumonia（ PSSP）. The FIC≤0. 5 and 0. 5〈FIC≤1 accounted for 0%,1〈FIC≤2 accounted for 14. 3%,FIC〉2 accounted for 85. 7%. Conclusion Combination of penicillinin combination with ceftriaxone may show synergism for PRSP and PISP,but antagonism for PSSP.