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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
12:18

Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)

Published on: February 9, 2011

Methicillin distribution in serum and extravascular fluid and its relevance to normal and damaged heart valves

F M Gengo, J J Schentag

    Antimicrobial Agents and Chemotherapy
    |May 1, 1981
    PubMed

    Insights

    Methicillin distributes unevenly in heart valves, with higher concentrations in damaged valves. Subcutaneous tissue chambers inaccurately reflect antibiotic uptake in heart tissues and valves.

    Area of Science:

    • Pharmacology
    • Cardiovascular Medicine
    • Infectious Diseases

    Background:

    • Antibiotic penetration into cardiac tissues is crucial for treating endocarditis.
    • Understanding methicillin distribution in normal versus damaged heart valves is essential for optimizing therapy.
    • Subcutaneous tissue chambers are sometimes used to estimate drug concentrations in deeper tissues.

    Purpose of the Study:

    • To determine methicillin distribution in normal and damaged heart valves.
    • To assess the accuracy of subcutaneous plastic chambers in reflecting methicillin tissue uptake.
    • To investigate the relationship between methicillin infusion dose and tissue concentrations.

    Main Methods:

    • Constant infusion of methicillin in New Zealand rabbits.
    • Induction of heart valve damage via left ventricular catheterization.
    • Subcutaneous implantation of perforated plastic chambers.
    • Measurement of methicillin concentrations in serum, urine, tissue chambers, heart valves, and heart muscle.

    Main Results:

    • Over 80% of the methicillin dose was recovered in serum, urine, and tissues.
    • Subcutaneous chamber fluid concentrations mirrored serum concentrations at steady state.
    • Methicillin concentrations in scarred heart valves were significantly higher than in normal valves.
    • Subcutaneous chambers did not accurately represent methicillin uptake rates in heart tissues and valves.

    Conclusions:

    • Methicillin uptake is altered in scarred heart valves compared to normal valves.
    • Subcutaneous tissue chambers are unreliable for estimating methicillin concentrations in heart tissues and valves.
    • Further research is needed to accurately predict antibiotic penetration into cardiac structures.

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