Mycobacterium tuberculosis Complex Detection and Rifampin Resistance, NAA With AFB Culture, Nonsputum
Use
This test is used to detect and identify Mycobacterium tuberculosis complex and an rpoB mutation that is associated with rifampin resistance.
Special Instructions
For optimal results, specimens should be transported immediately under refrigerated conditions. It is critical that the sample is divided at the time of collection for transportation at the appropriate temperature if needed for additional testing. The sample must meet minimum volume requirements, and avoid causes of rejection such as inappropriate transport devices or specimen leakage.
Limitations
The assay should not be used for patients who have undergone antituberculous treatment for more than three days. It is not suitable for monitoring therapy nor as a cure test. The sensitivity of the assay may be compromised in the presence of interfering substances such as lidocaine, mucin, ethambutol, guaifenesin, phenylephrine, and tea tree oil. Moreover, pediatric patients may show lower sensitivity due to the diffuse nature of the infection in this group and challenges in obtaining adequate samples. A negative test does not conclusively exclude M. tuberculosis complex from culture.
Methodology
PCR-based (Nested real-time PCR)
Biomarkers
LOINC Codes
- 89371-9
- 50941-4
- 31208-2
- 38379-4
- 89372-7
- 8100-0
Result Turnaround Time
48-56 days
Related Documents
For more information, please review the documents below
Specimen
Body Fluid
Volume
2 mL
Minimum Volume
2 mL
Container
Sterile cup; CSF (cerebrospinal fluid); sterile screw-capped vial
Storage Instructions
Refrigerate. If sample is to be split for other tests, specimen should be divided at the time of collection so that each portion is transported at the appropriate temperature.
Causes for Rejection
Quantity not sufficient; inappropriate specimen source (i.e., not BAL, CSF or pleural fluid); specimen submitted on a swab; specimen received after leaking out of transport container into the specimen bag; inappropriate or expired specimen transport device; syringe with attached needle; unlabeled specimen container or container with a single patient identifier; name discrepancy between the specimen container label and the computer or the requisition; specimen received after prolonged delay (more than seven days); specimen in a paraffin block; specimen in a fixative; specimen at room temperature received after 72 hours; specimen received frozen
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 7 days |