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A 1.5 Hour Procedure for Identification of Enterococcus Species Directly from Blood Cultures
05:02

A 1.5 Hour Procedure for Identification of Enterococcus Species Directly from Blood Cultures

Published on: February 10, 2011

High incidence of hemolysin production by Enterococcus (Streptococcus) faecalis strains associated with human

Y Ike, H Hashimoto, D B Clewell

    Journal of Clinical Microbiology
    |August 1, 1987
    PubMed

    Insights

    Most clinical Enterococcus faecalis isolates produce hemolysin, a trait linked to clumping response and drug resistance. Hemolysin determinants are transferable, but not linked to drug resistance genes.

    Area of Science:

    • Microbiology
    • Clinical Infectious Diseases

    Background:

    • Enterococcus faecalis is an opportunistic pathogen.
    • Hemolysin production and clumping factor are virulence factors in Enterococcus faecalis.

    Purpose of the Study:

    • To investigate hemolysin production, clumping response, and drug resistance in clinical isolates of Enterococcus faecalis.
    • To determine the transferability of the hemolytic trait and its association with drug resistance.

    Main Methods:

    • Analysis of 97 clinical isolates of Enterococcus faecalis from diverse sources.
    • Assessment of hemolysin production, clumping response, and antibiotic resistance profiles.
    • Evaluation of the transferability of hemolysin determinants.

    Main Results:

    • Approximately 60% of isolates were hemolytic.
    • Hemolytic strains showed a higher prevalence of clumping response (85%) compared to nonhemolytic strains (49%).
    • Over 50% of hemolytic strains possessed transferable hemolysin determinants, independent of drug resistance genes. Hemolytic strains were more frequently multidrug-resistant.

    Conclusions:

    • Hemolysin production is common in clinical Enterococcus faecalis isolates and associated with clumping factor and increased drug resistance.
    • The hemolytic trait is transferable but not linked to drug resistance genes in these isolates.

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