Clsi Document M45 Pdf May 2026

: Tentative guidance for certain potential agents, as seen in the CLSI AST Newsletter . Current Edition and Availability

: Vibrio species and Campylobacter jejuni/coli .

: "Breakpoints" (susceptible, intermediate, or resistant) tailored to the unique growth characteristics of these bacteria. clsi document m45 pdf

Clinical microbiology laboratories frequently encounter common pathogens like E. coli or Staphylococcus aureus , which are well-documented in standard AST protocols. However, or fastidious bacteria—which have complex nutritional requirements or occur rarely in clinical specimens—require modified testing conditions. The M45 document provides:

The guideline is indispensable for testing a diverse range of pathogens, including but not limited to: : Tentative guidance for certain potential agents, as

: Specialized advice on drug selection, incubation environments (e.g., increased CO2cap C cap O sub 2 ), and quality control (QC) procedures. Organisms Covered in CLSI M45

: Abiotrophia and Granulicatella species (nutritionally variant streptococci), Aeromonas species, Pasteurella species, and the HACEK group (e.g., Aggregatibacter , Cardiobacterium ). The M45 document provides: The guideline is indispensable

: Detailed instructions for performing broth microdilution and agar disk diffusion for specific "non-standard" organisms.

: Listeria monocytogenes , Corynebacterium species, Bacillus species (excluding B. anthracis ), and Erysipelothrix rhusiopathiae .

The document, titled Methods for Antimicrobial Dilution and Disk Susceptibility Testing of Infrequently Isolated or Fastidious Bacteria , is a specialized guideline developed by the Clinical and Laboratory Standards Institute (CLSI) . It serves as a critical extension to the primary antimicrobial susceptibility testing (AST) standards, specifically covering organisms that are not included in the more common CLSI M100 supplement. Core Purpose and Scope