| Ordering Code | 6555 |
|---|---|
| Test Name | MTB/RIF Assay by Real-time PCR |
| Alias | MTB Direct MTB DNA Direct Amplification **Cannot be ordered without an AFB smear and culture** **Will not be tested if a previous MTB/RIF test was done within the last month** |
| Preferred Specimen | Processed Respiratory Specimen Unprocessed Respiratory Specimen |
| Preferred Container | Sputum Collection Tube Sterile Container |
| Other Specimen/Container | Non-respiratory Specimens (Consult with Microbiology Technical Director) |
| Optimum Volume | Respiratory Specimens: 2 mL |
| Collection Instructions | Processed Respiratory Specimen: Sediment prepared by according to the method of NALC and re-suspended in 67 mM Phosphate/H20 buffer |
| Transport Requirements | Respiratory Specimens: Oahu: Refrigerated, Airline: Refrigerated Previous frozen sediment can be transported frozen. |
| Specimen Stability | Respiratory Specimens: Ambient: 3 Days, Refrigerated: 10 Days |
| Rejection Criteria | Mislabeled or unlabeled specimen, Specimen with obvious food particles or other solid particulate |
| Avail. Stat | NO |
| Analytic Time | Respiratory Specimens: 2 Hours |
| Methodology | Real-time PCR |
Reference range(s)
The reference ranges listed below are valid on this date of May 21, 2025.
| Component | Age | Male Norm | Male Critical Low | Male Critical High | Female Norm | Female Critical High | Female Critical Low | Units | Add'l info |
|---|---|---|---|---|---|---|---|---|---|
| Source: | ALL | See report. | |||||||
| M. tuberculosis DNA | ALL | NOT DETECTED | NOT DETECTED | The Xpert MTB/RIF... Note1 |
|||||
| Rifampicin Resistance | ALL | NOT DETECTED | NOT DETECTED |
Note1:
The Xpert MTB/RIF not only detects the presence ofMTB-complex DNA, but also mutations associated with resistance to rifampin, a surrogate marker for multidrug-resistant TB (MDR-TB)
Results from the Xpert MTB/RIF should be interpreted in the conjunction with other laboratory and clinical data..