Antimicrobial Susceptibility Testing On Selected Aerobes, Facultative Anaerobes, and Strict Anaerobes

Antimicrobial Susceptibility Testing (AST) is done by the broth microdilution method as described by the Clinical and Laboratory Standards Institute (CLSI) guidelines. AST is done on the following organisms that are cited in the CLSI guidelines (see references):

• Abiotrophia spp. 
• HACEK Group^¥ 
• Acinetobacter spp.
• Lactobacillus spp.
• Aerobic Actinomycetes  
• Leuconostoc spp. 
• Bacillus spp. (excluding B. anthracis)  
• Moraxella catarrhalis 
• Bacteroides fragilis group
• Non-Enterobacteriaceae Gram negative fermenters/non-fermenters
• Burkholderia cepacia
• Pasteurella spp
• Corynebacterium spp.
• Pediococcus spp.
• Coryneforms^§ 
• Pseudomonas spp. including P. aeruginosa
• Enterococcus spp . 
• Staphylococcus spp. (excluding S. aureus)
• Erysipelothrix rhusiopathiae
• Stenotrophomonas maltophilia
• Granulicatella spp. 
• Streptococcus spp. (excluding Group A & B Streptococcus,S.pneumoniae)

^§ Includes the Genera Arcanobacterium, Brevibacterium, Cellulomonas, Dermabacter, Leifsonia, Microbacterium, Oerskovia, Rothia, and Turicella

^¥ Aggregatibacter spp., Cardiobacterium spp., Eikenella corrodens., Kingella spp.

Pure cultures of isolates recovered from normally sterile sites and serious wound infections.

Slants or plates of any suitable media and swabs in transport media are all acceptable.

Store samples at room temperature until shipped for testing. Ship at room temperature.

Shipping of specimens shall be done by a TDG certified individual in accordance with TDG regulations. For additional information regarding classification of specimens for the purposes of shipping, consult either Part 2 Appendix 3 of the TDG Regulations or section 3.6.2 of the IATA Dangerous Goods Regulations as applicable.

Clinical illness with symptoms suggestive of bacterial infection.

Completed Special Bacteriology requisition form detailing all patient information and relevant clinical information. If possible, attach lab results that have already been done at local or provincial laboratories.

All patient and strain history must be included. Other non-mycobacterial, non-enteric, Gram positive/negative bacteria which are not described by a CLSI guideline may be tested upon request and at the discretion of the Special Bacteriology Laboratory. Testing does not include any Risk Group 3 organisms.

Broth microdilution using commercially-available Sensititre® panels. Interpretations are based on the most recent CLSI guidelines. Interpretations for rare or undescribed taxons may not be possible.

16 calendar days. In cases where staff or resources are limited final report may be delayed and status of request will be forwarded in a preliminary report. Poor- or slow-growing isolates may require longer turn around times.

1. Clinical and Laboratory Standards Institute. 2014. Performance Standards for Antimicrobial Susceptibility Testing; Twenty-Fourth Informational Supplement. Volume 34. Number 1. M100-S24. Clinical and Laboratory Standards Institute, Wayne, Pa.
2. Clinical and Laboratory Standards Institute. 2011. Susceptibility Testing of Mycobacteria, Nocardiae, and Other Aerobic Actinomycetes; Approved Standard-Second Edition. Volume 31. Number 5. M24-A2. Clinical and Laboratory Standards Institute, Wayne, Pa.
3. Clinical and Laboratory Standards Institute. 2010. Methods for Antimicrobial Dilution and Disk Susceptibility Testing of Infrequently Isolated or Fastidious Bacteria; Approved Guideline-Second Edition. Volume 30. Number 18. M45-A2. Clinical and Laboratory Standards Institute, Wayne, Pa.
4. Clinical and Laboratory Standards Institute. 2012. Methods for Antimicrobial Susceptibility Testing of Anaerobic Bacteria; Approved Standard-Eighth Edition. Volume 32. Number 5. M11-A8. Clinical and Laboratory Standards Institute, Wayne, Pa.