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[Pathogenicity factors of enterococci of human intestinal microflora]

A V Valyshev, N V Gertsen

    Zhurnal Mikrobiologii, Epidemiologii I Immunobiologii
    |September 4, 2012
    PubMed
    Abstract

    Insights

    Pathogenicity factors like hemolysin are present in some human fecal enterococci. A few strains exhibit multiple factors, potentially contributing to endogenous infections in immunocompromised individuals.

    Area of Science:

    • Microbiology
    • Clinical Microbiology
    • Pathogen Discovery

    Background:

    • Enterococci are common commensals in the human gut.
    • Certain enterococcal species possess virulence factors that can contribute to disease.
    • Understanding the prevalence of these factors is crucial for assessing infection risk.

    Purpose of the Study:

    • To characterize pathogenicity factors in enterococci isolated from human feces.
    • To determine the prevalence of hemolysin, gelatinase, and DNase production.
    • To identify enterococcal species associated with these virulence factors.

    Main Methods:

    • 161 enterococcal isolates from human feces were cultured.
    • Production of hemolysin, gelatinase, and DNase was assessed.
    • Species identification was performed for hemolytic strains.

    Main Results:

    • Hemolytic activity was the most common factor (14.9%), primarily in *E. faecalis*.
    • Gelatinase activity was found in 7.5% of cultures.
    • Deoxyribonuclease (DNase) activity was detected in one *E. faecalis* strain.
    • *E. faecalis* strains sometimes exhibited multiple factors, such as hemolysis and gelatin hydrolysis.

    Conclusions:

    • Pathogenicity factors are relatively rare in intestinal enterococci.
    • Enterococcal strains producing multiple virulence factors may play a role in endogenous infections.
    • Immunocompromised patients are particularly at risk from such infections.

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