Abstract
In an effort to determine the adequacy of a standard broth medium in the evaluation of antibiotic combinations, 20 strains of various bacterial species were studied simultaneously in Mueller-Hinton broth and in freshly drawn human serum from apparently healthy volunteers. Studies of growth dynamics by use of the usual plate dilution technique for quantitating colony-forming units were performed with strains of Staphylococcus aureus (methicillin-resistant and methicillin-susceptible), Streptococcus faecalis, Escherichia coli, Aerobacter, Klebsiella, and Proteus mirabilis. A variety of different antibiotics were investigated. With 19 of the 20 strains, interpretations of synergism or antagonism were the same in both media. Therefore, despite minor variations when the same strain was studied in both serum and broth, it is concluded that Mueller-Hinton broth is an adequate medium for use in studies of chemotherapeutic combinations in vitro. A simplified method for studying bactericidal activity is described, which is deemed practical for clinical microbiology laboratories and which led to the same conclusions regarding the combinations as were obtained by the more arduous plate dilution test.
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Selected References
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- BULGER R. J., KIRBY W. M. GENTAMICIN AND AMPICILLIN: SYNERGISM WITH OTHER ANTIBIOTICS. Am J Med Sci. 1963 Dec;246:717–726. doi: 10.1097/00000441-196312000-00013. [DOI] [PubMed] [Google Scholar]
- Bulger R. J. In vitro effectiveness of kanamycin and kanamycin/cephalothin against Klebsiella. Comparison with other antibiotics. Ann Intern Med. 1967 Sep;67(3):523–532. doi: 10.7326/0003-4819-67-3-523. [DOI] [PubMed] [Google Scholar]
- Bulger R. J. In-vitro activity of cephalothin/kanamycin and methicillin/kanamycin combinations against methicillin-resistant Staphylococcus aureus. Lancet. 1967 Jan 7;1(7480):17–19. doi: 10.1016/s0140-6736(67)92422-1. [DOI] [PubMed] [Google Scholar]
- Dowling H. F. An overview of the use of combinations of antibiotics. Antimicrob Agents Chemother (Bethesda) 1967;7:234–235. [PubMed] [Google Scholar]
- Dowling H. F. Present status of therapy with combinations of antibiotics. Am J Med. 1965 Nov;39(5):796–811. doi: 10.1016/0002-9343(65)90098-7. [DOI] [PubMed] [Google Scholar]
- Jawetz E. Combined antibiotic action: some definitions and correlations between laboratory and clinical results. Antimicrob Agents Chemother (Bethesda) 1967;7:203–209. doi: 10.1128/AAC.7.2.203. [DOI] [PubMed] [Google Scholar]