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Combination effect with some aminoglycoside antibiotics

Z Jedlicková, M Rýc, A Libánská

    Journal of Hygiene, Epidemiology, Microbiology, and Immunology
    |January 1, 1981
    PubMed

    Insights

    This study investigated antibiotic combinations against resistant bacteria like Staphylococcus aureus and Pseudomonas aeruginosa. Sisomicin combinations showed promise, particularly with carfecillin and doxycycline, for treating nosocomial infections.

    Area of Science:

    • Medical Microbiology
    • Infectious Diseases
    • Pharmacology

    Background:

    • Nosocomial infections pose a significant threat, often caused by antibiotic-resistant bacteria.
    • Staphylococcus aureus, Streptococcus faecalis, and Pseudomonas aeruginosa are common pathogens in hospital-acquired infections.
    • Rising antibiotic resistance necessitates exploring novel therapeutic strategies, including drug combinations.

    Purpose of the Study:

    • To evaluate the synergistic and antagonistic effects of various chemotherapeutic combinations against resistant bacterial strains.
    • To identify effective antibiotic combinations for treating infections caused by Staphylococcus aureus, Streptococcus faecalis, and Pseudomonas aeruginosa.
    • To assess the potential of sisomicin-based combinations in combating multidrug-resistant pathogens.

    Main Methods:

    • Bacterial strains (Staphylococcus aureus, Streptococcus faecalis, Pseudomonas aeruginosa) isolated from nosocomial infections were tested.
    • In vitro susceptibility testing was performed to assess the combined effects of different antibiotic agents.
    • Specific combinations evaluated included sisomicin with carfecillin, doxycycline, chloramphenicol, and amoxycillin/carbenicillin.

    Main Results:

    • Sisomicin-carfecillin and sisomicin-doxycycline combinations were effective in 50% of Pseudomonas aeruginosa cases.
    • Sisomicin-chloramphenicol exhibited antagonistic effects in one-third of Pseudomonas aeruginosa strains tested.
    • Sisomicin-carfecillin and sisomicin-doxycycline showed potentiation in over half and one-third of Staphylococcus aureus strains, respectively.
    • Sisomicin combined with amoxycillin, carbenicillin, carfecillin, or doxycycline demonstrated synergistic action in over half of Streptococcus faecalis strains, with no antagonism observed.

    Conclusions:

    • Certain sisomicin-based antibiotic combinations, particularly with carfecillin and doxycycline, show significant potential against resistant Gram-positive and Gram-negative bacteria.
    • Understanding drug interactions (synergy and antagonism) is crucial for optimizing antibiotic therapy in managing nosocomial infections.
    • Further research into combination therapies is warranted to address the growing challenge of antimicrobial resistance in clinical settings.

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