Mycobacterium tuberculosis Complex Detection and Rifampin Resistance by PCR
Also known as: MTBRIF PCR
Use
The Mycobacterium tuberculosis Complex Detection and Rifampin Resistance by PCR test is crucial for detecting M. tuberculosis complex isolates and determining potential resistance to rifampin treatment. Its utility lies in its ability to rapidly identify the presence of M. tuberculosis and assess drug resistance, specifically rifampin resistance, which is a key part of tuberculosis management and helps guide effective antibiotic treatment strategies. While molecular testing offers speed, the test complements culture methods, which remain the gold standard, by providing immediate insights in a clinical setting.
Special Instructions
Specimen source is required for the test order, with details on whether the specimen has been processed, including the method for digestion and decontamination; smear results must be provided. Delayed results may occur if this information is lacking. Body fluids other than pleural fluid will be run with a disclaimer. Repeat testing is not clinically indicated after a positive result as it will continue to yield positive outcomes.
Limitations
The mycobacterial culture is considered more sensitive than the molecular method used in this test. Therefore, if possible, culture testing should be performed regardless of PCR test results to ensure comprehensive diagnosis. The test's performance has not been evaluated in samples from pediatric patients. Additionally, processed specimens may offer different diagnostic sensitivities depending on the digestion and decontamination process used.
New York Approved
Methodology
PCR-based (Qualitative PCR)
Biomarkers
LOINC Codes
- 31208-2
- 38379-4
- 89372-7
- 93479-4
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Bronchoalveolar Lavage
Volume
5-10 mL
Minimum Volume
1 mL
Container
Sterile container
Collection Instructions
Unprocessed specimens: Transport 5-10 mL respiratory specimen, CSF or pleural fluid in a sterile container. Processed specimens: Transport 2-5 mL digested/decontaminated specimen in a sterile container.
Storage Instructions
Refrigerated
Causes for Rejection
Blood, paraffin blocks, stool, swabs, and urine.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 3 days for unprocessed, unacceptable for processed |
| Refrigerated | 1 week |
| Frozen | 1 month |
Other tests from different labs that may be relevant