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Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method
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Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method

Published on: April 18, 2019

[Synergism of colistin and sulfonamide in proteus species (author's transl)]

H H Kunz

    Arzneimittel-Forschung
    |November 1, 1975
    PubMed

    Insights

    Colistin (C) and sulfonamide (S) exhibit a synergistic effect against Proteus infections. This combination significantly enhances sulfonamide sensitivity in Proteus strains, suggesting therapeutic potential.

    Area of Science:

    • Microbiology
    • Pharmacology
    • Infectious Diseases

    Background:

    • Proteus species are common causes of urinary tract and other infections.
    • Sulfonamide resistance is a growing concern in treating Proteus infections.
    • Colistin is a potent antibiotic, but its use is often limited.

    Purpose of the Study:

    • To investigate the synergistic effect of colistin and sulfonamide against Proteus strains.
    • To quantitatively evaluate the enhanced sensitivity to sulfonamide when combined with colistin.
    • To assess the therapeutic potential of the colistin-sulfonamide combination for Proteus infections.

    Main Methods:

    • Agar diffusion testing was initially performed on sulfonamide-sensitive Proteus mirabilis strains.
    • Quantitative evaluation using broth dilution method was conducted on 100 strains of Proteus mirabilis and 100 strains of indol-positive Proteus spp.
    • The combination ratio of 1 part colistin to 10 parts sulfonamide was tested.

    Main Results:

    • A significant synergistic effect between colistin and sulfonamide was observed.
    • The mean increase in sulfonamide sensitivity was fourfold when combined with colistin.
    • Proteus sensitivity to the colistin-sulfonamide combination remained within therapeutic blood levels even with increased inoculum.

    Conclusions:

    • The combination of colistin and sulfonamide demonstrates a positive synergistic effect against Proteus.
    • This synergistic effect significantly enhances sulfonamide efficacy, overcoming resistance.
    • The colistin-sulfonamide combination warrants consideration for the treatment of Proteus infections.

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