251. In Vitro Minimum Bactericidal Concentration of Iodine against Emergent Surgical Pathogens
Session: Poster Abstract Session: Antimicrobial Susceptibility and Resistance
Friday, October 21, 2011
Room: Poster Hall B1
Handouts
  • MBC of Iodine against Emergent Surgical Pathogens Poster for IDSA.pdf (532.5 kB)
  • Background: Minimum bactericidal concentrations (MBCs) of 3M™ DuraPrep™ Surgical Solution (Iodine Povacrylex [0.7% available iodine] and Isopropyl Alcohol, 74% w/w) Patient Preoperative Skin Preparation were previously determined according to the United States Food and Drug Administration’s (FDA’s) Proposed Tentative Final Monograph (TFM) for Health-Care Antiseptic Drug Products.  However, the emergence of new clinical pathogens, along with the development of drug resistance in several important classes of organisms, has resulted in the need to determine MBCs for those organisms not previously evaluated.

    Methods: Evaluation of the test material was based on a method for determining the MBC of povidone-iodine against Staphylococcus aureus. This method was modified to incorporate aspects of the Clinical and Laboratory Standards Institute® (CLSI) Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically. DuraPrep solution was tested against various reference strains and clinical isolates using twofold serial dilutions. The lowest concentration that resulted in complete kill of the organism after 30 minutes of contact time was recorded as the MBC for available iodine.

    Results: 

    The MBC ranges for DuraPrep solution against Propionibacterium acnes, community-associated and healthcare-associated methicillin-resistant Staphylococcus aureus (CA-MRSA and HA-MRSA), and multidrug-resistant (MDR) strains of Acinetobacter baumannii , Burkholderia cepacia complex and Escherichia coli are listed in the following table.

     

    Microorganism

    Reference Strains

    Clinical Isolates

    N

    MBC Range (µg /mL)

    N

    MBC Range (µg /mL)

    P. acnes

    10

    0.25-1

    25

    0.25-1

    CA-MRSA

    1

    0.5

    25

    0.25-1

    HA-MRSA

    0

    Not applicable

    25

    0.5-1

    MDR A. baumannii

    12

    0.25-1

    27

    0.5-1

    MDR B. cepacia complex

    1

    1

    25

    0.5-4

    MDR E. coli

    6

    0.5-2

    27

    0.125-2

    Conclusion: All of the MBCs were well below the concentration of available iodine (6020 µg /mL) present in DuraPrep solution.


    Subject Category: A. Antimicrobial agents and Resistance

    Kathryn Dormstetter, BS1, Linda Olson, BS2 and Sally Bull, BS, CCRA2, (1)MICROBIOTEST, a Division of Microbac Laboratories, Inc, Sterling, VA, (2)Infection Prevention Division, 3M Health Care, St. Paul, MN

    Disclosures:

    K. Dormstetter, 3M Health Care: Research Contractor, Research support

    L. Olson, 3M Health Care: Employee, Salary

    S. Bull, 3M Health Care: Employee, Salary

    Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.