Mycobacterium tuberculosis Complex and Rifampin Resistance, PCR, Sputum
Also known as: MTB complex, Xpert MTB/Rif, Tuberculosis, TB, Rifampin Resistance
Use
Rapid molecular detection of Mycobacterium tuberculosis complex DNA from respiratory specimens (sputum) for the diagnosis of pulmonary tuberculosis and presumptive detection of rifampin resistance based on mutations in the rpoB gene per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic consistent with CLIA requirements. NY State approval: Yes. FDA cleared/approved or exempt. CLIA performed. CAP proficiency maintained.
Special Instructions
Specimens must be processed in contamination‑controlled environment. Concurrent mycobacterial culture is required for strain typing and definitive rifampin susceptibility. Ship specimen within 7 days of collection; insufficient volume may decrease sensitivity or lead to cancellation. Use Cepheid Xpert MTB/RIF closed cartridge system.
Limitations
This molecular assay does not distinguish viable organisms from residual DNA and negative result does not rule out active disease. Rifampin resistance findings are presumptive pending confirmation by sequencing or phenotypic susceptibility testing. Culture remains necessary for epidemiologic typing and full susceptibility profile.
FDA ApprovedNew York Approved
Methodology
PCR-based (PCR)
Biomarkers
LOINC Codes
- 89371-9
- 31208-2
- 88874-3
- 89372-7
Result Turnaround Time
0-1 days
Related Documents
For more information, please review the documents below
Specimen
Tissue (Unknown)
Volume
3 mL
Minimum Volume
1.5 mL
Container
Sterile container
Collection Instructions
Sputum (undigested) or N‑acetyl‑L‑cysteine/sodium hydroxide (NALC/NaOH)‐digested sputum treated and clearly indicated; if shared with culture or smear, minimum 3 mL.
Storage Instructions
Refrigerated (preferred) 7 days; ambient 72 hours
Causes for Rejection
Insufficient volume; contamination; improper labeling
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 7 days |