Levine J F, Hanna B A, Pollock A A, Simberkoff M S, Rahal J J
Am J Med Sci. 1983 Jul-Aug;286(1):31-6. doi: 10.1097/00000441-198307000-00005.
Studies to date have indicated that nutritionally-variant streptococci (NVS) causing bacterial endocarditis are frequently inhibited but not killed by low concentrations of penicillin. We report a patient with endocarditis due to a NVS strain which was killed in vitro by penicillin at a concentration of 0.09 microgram/ml. Despite therapy with intravenous penicillin for four weeks, the infection relapsed and was then cured by combined penicillin-gentamicin in therapy. In vitro studies demonstrated a synergistic effect of these two antibiotics. This experience suggests that combination therapy with penicillin and an aminoglycoside may be required for cure of all cases of nutritionally-variant streptococcal endocarditis regardless of in vitro susceptibility to penicillin.
迄今为止的研究表明，引起细菌性心内膜炎的营养变异型链球菌（NVS）常被低浓度青霉素抑制但未被杀死。我们报告1例由NVS菌株引起的心内膜炎患者，该菌株在体外被浓度为0.09微克/毫升的青霉素杀死。尽管静脉注射青霉素治疗4周，但感染复发，随后联合青霉素-庆大霉素治疗得以治愈。体外研究显示这两种抗生素有协同作用。这一经验表明，无论体外对青霉素的敏感性如何，治疗所有营养变异型链球菌心内膜炎病例可能都需要青霉素与氨基糖苷类联合治疗。
