Francioli P, Moreillon P, Glauser M P
J Infect Dis. 1985 Jul;152(1):83-9. doi: 10.1093/infdis/152.1.83.
Recent recommendations for the prophylaxis of endocarditis in humans have advocated single doses or short courses of antibiotic combinations (beta-lactam plus aminoglycoside) for susceptible patients in whom enterococcal bacteremia might develop or for patients at especially high risk of developing endocarditis (e.g., patients with prosthetic cardiac valves). We tested the prophylactic efficacy (in rats with catheter-induced aortic vegetations) of single doses of amoxicillin plus gentamicin against challenge with various streptococcal strains (two strains of Streptococcus faecalis, one of Streptococcus bovis, and three of viridans streptococci); we then compared this efficacy with that of single doses of amoxicillin alone. Successful prophylaxis against all six strains was achieved with single doses of both amoxicillin alone and amoxicillin plus gentamicin. This protection, however, was limited, for both regimens, to the lowest bacterial-inoculum size producing endocarditis in 90% of control rats and was not extended to higher inocula by using the combination of antibiotics. We concluded that a single dose of amoxicillin alone was protective against enterococcal and nonenterococcal endocarditis in the rat, but that its efficacy was limited and could not be improved by the simultaneous administration of gentamicin.
近期关于人类心内膜炎预防的建议主张，对于可能发生肠球菌菌血症的易感患者或发生心内膜炎风险特别高的患者（如有人造心脏瓣膜的患者），采用单剂量或短疗程抗生素联合用药（β-内酰胺类加氨基糖苷类）。我们测试了单剂量阿莫西林加庆大霉素对各种链球菌菌株（两株粪肠球菌、一株牛链球菌和三株草绿色链球菌）攻击（在导管诱导的大鼠主动脉赘生物模型中）的预防效果；然后将此效果与单剂量阿莫西林的效果进行比较。单剂量的阿莫西林以及阿莫西林加庆大霉素均成功预防了所有六种菌株。然而，两种方案的这种保护作用都有限，仅限于在90%的对照大鼠中引发心内膜炎的最低细菌接种量，并且通过联合使用抗生素并不能将保护作用扩展到更高的接种量。我们得出结论，单剂量的阿莫西林本身对大鼠的肠球菌性和非肠球菌性心内膜炎具有保护作用，但其效果有限，同时给予庆大霉素并不能提高其疗效。
