Broth Microdilution MIC Panels for Non-tuberculous Mycobacteria (NTM)

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Accredited by the Standards Council of Canada to Laboratory no. 594 (ISO/IEC 17025)

Requisition Forms

Reference Details

Description:

Determine minimum inhibitory concentration (MIC) of first and second line antimicrobials for non-tuberculosis mycobacteria (NTM).

Test Category:
Susceptibility Testing
Pathogen:
Mycobacterium spp.
Illnesses and Diseases:
  • Pulmonary Disease
  • Non-pulmonary disease
Specimen:

Solid media growth is required

  • Isolated colonies on plated media. 
  • Cultures must show visible growth on solid media..
  • Rapidly growing Mycobacterium species must be no more than 10 days old.
  • Slowly growing Mycobacterium species must be no more than 4 weeks old.
  • If the culture has inadequate growth, contamination, or mixed Mycobacterium species, the submitted culture will be rejected and a resubmission will be requested. 
Collection Method:

N/A

Specimen Processing, Storage and Shipping:

Ship cultures at room temperature (DO NOT freeze) for overnight delivery, and prior to Wednesday each week to ensure receipt by Friday.

Transportation of Dangerous Goods:

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.

For additional guidance on the transport of infectious substances in other languages, please click on the link below.

http://www.who.int/ihr/capacity-strengthening/infectious-substances/en/

 

Patient Criteria:

Respiratory samples must meet the ATS recommendations for clinical significance.  For non-respiratory samples, the CLSI guidelines state, “susceptibility testing of NTM should be considered only for those isolates believed to be clinically significant. Isolates from blood, other sterile body fluids or tissues are generally considered clinically significant;” Justification and clinical history must be provided with the requisition form. Samples submitted for clofazimine testing must be clinically significant AND isolates must be from patients who develop bacteremia while on macrolide therapy or from patients who relapse while on macrolide therapy or other NTM cases with clinical justification. Testing will be performed when physician intends to use clofazimine for treatment.

Accompanying Documentation:

Notification of sample submission must be emailed or faxed prior to shipping isolates. Samples should be shipped attention: Catherine

 

Yoshida, Head, Reference and Diagnostic Services, NRCM/NML at 204-789-2136.  A requisition and Request for Susceptibility testing of Nontuberculous Mycobacteria (NTM) must be completed and signed off by the supervisor/designate of the submitting laboratory.  The requisition must include the source of specimen, patient gender, date of birth, clinical history, submitting laboratory identifier and submitter information.  Please also include isolate characteristics:  microscopy, pigmentation, culture characteristics, growth rate/temperature, and identification.  Please specify your clofazimine request in “other” in the “Susceptibility Testing” section on the NRCM requisition.

Comments:

Cultures will be rejected if appropriate documentation and justification is incomplete or missing, or if an inappropriate culture is submitted (see “Specimen”).

Methods and Interpretation of Results:

Rapidly growing mycobacteria will be tested using RAPMYCO Sensititre Panels and slowly growing mycobacteria will be tested using SLOMYCO Sensititre Panels. Interpretations of antimicrobial sensitivities will be provided as per the CLSI (2) guidelines when available. For species with no CLSI guidelines, MIC values for antibiotics will be provided.

Turnaround Time:

45 days from the date specimen is received.

Contact:
Phone: (204) 789-2136 or (204) 789-6038
Fax: (204) 789-2036
References:
  1. CLSI. Susceptibility Testing of Mycobacteria, Nocardia and Other Aerobic Actinomycetes. 3rd ed. CLSI standard M24. Clinical and Laboratory Standards Institute; 2018.
  2. CLSI. Performance Standards for Susceptibility Testing of Mycobacteria, Nocardia spp., and Other Aerobic Actinomycetes. 1st ed. CLSI standard M62. Clinical and Laboratory Standards Institute: 2018.
  3. Griffith DE, Aksamit T, Brown-Elliott BA, et al. An official ATS/IDSA statement: diagnosis, treatment, and prevention of nontuberculous mycobacterial diseases. Am J Respir Crit Care Med. 2007 Feb 15;175(4):367-416.