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CLSI Publishes M100—Performance Standards for Antimicrobial Susceptibility Testing, 33rd Edition


Malvern, Pennsylvania, USA—The Clinical and Laboratory Standards Institute (CLSI) has published M100—Performance Standards for Antimicrobial Susceptibility Testing, 33rd Edition.

The tables presented in M100 represent the most current information for drug selection, interpretation, and quality control using the procedures standardized in CLSI documents M02, M07, and M11. This document is intended for use by microbiology labs, antimicrobial stewardship teams, infectious disease experts, and other relevant stakeholders intending to provide optimal patent care using the most up-to-date antimicrobial susceptibility breakpoints and test methods. To ensure the correct use of the document, users should replace previously published tables with the new edition immediately.

"The 2023 M100 includes some major changes that both laboratories and clinicians need to be aware of in order to optimize the management of patients with bacterial infections," said James S. Lewis II, PharmD, FIDSA, Chairholder of the Subcommittee on Antimicrobial Susceptibility Testing (AST). "It's yet another reminder of why, in the rapidly changing world of infectious diseases, the work represented by the annual M100 updates is so important."

Shelley Campeau, PhD, D(ABMM), Co-chairholder of the Working Group on Text and Tables, said, "This year, several tables were modernized to introduce a new tiered approach suggesting which antimicrobial agents to consider for testing and reporting by microbiology labs." For a concise list of new antimicrobial susceptibility testing and reporting recommendations, users should review the listing of changes and additions in the new edition that are presented in the opening pages.

In addition, CLSI will host its Annual Updates Webinar, moderated by Janet Hindler, MCLS, MT(ASCP), F(AAM), of the Los Angeles Department of Public Health. It will be presented by Romney M. Humphries, PhD, D(ABMM) of Vanderbilt University and April M. Bobenchik, PhD, D(ABMM), MT(ASCP), Medical Director Microbiology, Associate Professor Pathology & Laboratory Medicine, of Penn State Health and Milton S. Hershey Medical Center. The webinar is designed to help users identify the major changes, learn implementation strategies, and suggest communication approaches for informing clinical staff of the significant AST and reporting changes. The webinar will take place twice, on both April 5 and 6, and will cover the same information.

CLSI is the leading global non-profit laboratory medicine standards development organization, with over 24,000 individuals with membership access, 2,000 volunteers, and 250 products. CLSI standards are recognized by laboratories, accreditors, and government agencies worldwide as the best way to improve medical laboratory testing. Organizations use CLSI standards to improve their testing outcomes, maintain accreditation, bring products to market faster, and navigate regulatory hurdles.

For more information on M100-Ed33, contact Joanne Christopher at jchristopher@clsi.org or +1.484.588.5907.


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