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Quantifying the Cytotoxicity of Staphylococcus aureus Against Human Polymorphonuclear Leukocytes
12:27

Quantifying the Cytotoxicity of Staphylococcus aureus Against Human Polymorphonuclear Leukocytes

Published on: January 3, 2020

SOME PHYSIOLOGICAL CHARACTERISTICS OF NEOMYCIN AND KANAMYCIN-RESISTANT STRAINS OF STAPHYLOCOCCUS AUREUS

S I JACOBS, A T WILLIS

    Journal of Clinical Pathology
    |November 1, 1964
    PubMed

    Insights

    Hospital-origin Staphylococcus aureus strains showed resistance to common antibiotics. A subset also exhibited neomycin and kanamycin resistance, linked to specific physiological markers and phage susceptibility.

    Area of Science:

    • Microbiology
    • Clinical Infectious Diseases

    Background:

    • Hospital-acquired Staphylococcus aureus infections pose significant treatment challenges due to antibiotic resistance.
    • Penicillin, streptomycin, and tetracycline resistance are common in clinical isolates.

    Purpose of the Study:

    • To investigate the characteristics of Staphylococcus aureus strains exhibiting resistance to multiple antibiotics, including neomycin and kanamycin.
    • To explore the relationship between antibiotic resistance patterns and physiological markers in these strains.

    Main Methods:

    • Phenotypic characterization of 552 hospital-origin Staphylococcus aureus strains.
    • Assessment of resistance to penicillin, streptomycin, tetracycline, neomycin, and kanamycin.
    • Evaluation of pigment production, beta-lysin, fibrinolytic, and proteolytic activity.
    • Phage susceptibility testing.

    Main Results:

    • All 552 strains were resistant to penicillin, streptomycin, and tetracycline.
    • 298 strains displayed additional resistance to neomycin and kanamycin.
    • Neomycin/kanamycin resistance correlated with pigment production, beta-lysin presence, absence of fibrinolytic/proteolytic activity, and specific phage susceptibility patterns.

    Conclusions:

    • Physiological markers can be associated with multidrug resistance in Staphylococcus aureus.
    • Phage typing may have limitations in characterizing certain resistant strains.
    • Understanding these markers is crucial for managing the emergence of antibiotic-resistant staphylococci.
    Keywords:
    BACTERIOLOGICAL TECHNICSBACTERIOPHAGE TYPINGCULTURE MEDIADRUG RESISTANCE, MICROBIALEXPERIMENTAL LAB STUDYFIBRINOLYSISHEMOLYSINSKANAMYCINNEOMYCINPENICILLINPIGMENTSSTAPHYLOCOCCUSSTREPTOMYCINTETRACYCLINE

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