Tubau F, Liñares J, Ardanuy C, Martínez-Lacasa J, Fernández A, Cabellos C, Fernández-Viladrich P, Martín R
Servicio de Microbiologia, Hospitalet de Llobregat, Barcelona.
Enferm Infecc Microbiol Clin. 1996 Dec;14(10):590-5.
To determinate the bactericidal activity of vancomycin, rifampicin, cefotaxime, ceftriaxone and their double and triple combinations against penicillin and third generation cephalosporin-resistant. Streptococcus pneumoniae strain.
A study of the bactericidal activity of antibiotics alone and in combination was performed by killing-curves with fixed concentration of 2 micrograms/ml, equivalent to 1 < MIC for cefotaxime and ceftriaxone, to 8 x MIC for vancomycin and to 32 < MIC for rifampin.
Vancomycin was the only antibiotic with bactericidal effect at 6 hours. Cefotaxime had bactericidal effect at 12 hours. Rifampin had no bactericidal effect. The association of vancomycin plus third generation cephalosporins (cefotaxime and ceftriaxone) showed indifferent effect. Rifampin decreased the bactericidal activity of vancomycin at 12 hours, when both were studied in combination, and it demonstrated antagonistic effect in the double and triple combination in which rifampicin was included.
All associations of vancomycin plus third generation cephalosporins were bactericidal effects, but they did no show synergistic effects against penicillin- and third generation cephalosporin S. pneumoniae strain 2349. All combinations with rifampin showed decreased bactericidal activity or antagonistic effects. However, these results may be interpreted with caution because the in vivo experience of an experimental meningitis model in rabbits showed that the associations of vancomycin plus rifampin and vancomycin plus cefotaxime and rifampin were effective combinations. More in vivo and in vitro comparative studies are needed to demonstrate the reliability of in vitro results.
测定万古霉素、利福平、头孢噻肟、头孢曲松及其双联和三联组合对耐青霉素和第三代头孢菌素的肺炎链球菌菌株的杀菌活性。
通过在固定浓度为2微克/毫升的杀菌曲线研究单独及联合使用抗生素的杀菌活性，该浓度相当于头孢噻肟和头孢曲松的1倍最低抑菌浓度（MIC）、万古霉素的8倍MIC以及利福平的32倍MIC。
万古霉素是6小时时唯一具有杀菌作用的抗生素。头孢噻肟在12小时时有杀菌作用。利福平无杀菌作用。万古霉素与第三代头孢菌素（头孢噻肟和头孢曲松）联合使用效果不佳。当联合研究时，利福平在12小时时降低了万古霉素的杀菌活性，并且在包含利福平的双联和三联组合中显示出拮抗作用。
万古霉素与第三代头孢菌素的所有联合使用均有杀菌作用，但对青霉素和第三代头孢菌素耐药的肺炎链球菌菌株2349未显示协同作用。所有与利福平的组合均显示杀菌活性降低或拮抗作用。然而，这些结果可能需要谨慎解读，因为兔实验性脑膜炎模型的体内实验表明，万古霉素加利福平以及万古霉素加头孢噻肟和利福平的联合使用是有效的组合。需要更多的体内和体外比较研究来证明体外结果的可靠性。
