Abstract
The minimal inhibitory concentrations (MIC) of sulfamethoxazole and trimethoprim against 144 strains of obligately anaerobic bacteria were determined on supplemented Diagnostic Sensitivity Test (Oxoid) agar or broth. 58% of the strains were susceptible to sulfamethoxazole alone (MIC less than or equal to 16 micrograms/ml), only 12% were susceptible to trimethoprim alone (less than or equal to 1 microgram/ml), and 85% were susceptible to the combination of sulfamethoxazole plus trimethoprim (less than or equal to 16 micrograms/ml) at a ratio of 19:1. All 45 strains of the Bacteroides fragilis group were susceptible to the combination. At a ratio of 1:1, 78% of the strains showed synergistic activity, at a ratio of 16:1 there were synergism in 54% of the strains. When the strains were tested by a modification of the broth-disc method in Diagnostic Sensitivity Test broth, there was over 98% correlation with the MIC. There was poor correlation between inhibition zone diameters by an agar diffusion method and MIC.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.