Please login to order a test.
Mycobacterium tuberculosis Complex Detection and Rifampin Resistance, NAA Without CAP-mandated Culture
Test Details
Use
Detect and identify Mycobacterium tuberculosis complex and an rpoB mutation that is associated with rifampin resistance. Per the College of American Pathologists (CAP) guidelines (MIC.64820), a culture must be performed on all samples regardless of the molecular test result. By ordering this test, the client has assumed responsibility for performance of the AFB culture.
Limitations
The assay should not be used to test specimens from pediatric patients or from patients who have been treated with antituberculous drugs for more than three days. The assay should not be used to monitor therapy or as a test of cure. A negative test does not exclude the possibility of isolating M tuberculosis complex isolates from culture. Assay interference may occur in the presence of lidocaine, mucin, ethambutol, guaifenesin, phenylephrine, and tea tree oil.
Methodology
Nucleic acid amplification (NAA) technology; nested real-time polymerase chain reaction (PCR)
Specimen Requirements
Specimen
Sputum (adult population) first morning specimen
Volume
2 mL of raw or expectorated sputum
Minimum Volume
2 mL
Container
Sterile screw-capped vial or sterile cup; seal securely.
Patient Preparation
When collecting sputum, have the patient brush teeth or remove dentures and rinse mouth with water. Instruct the patient not to collect saliva.
Storage Instructions
Refrigerate. Specimen may be stored at a maximum of 35°C for three days and then at 2°C to 8°C for seven days. Specimen may also be stored frozen (below -70°C).
Causes for Rejection
Quantity not sufficient; inappropriate specimen source; specimen from a pediatric patient; specimen received after leaking out of transport container into the specimen bag; inappropriate or expired specimen transport device; 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 unless frozen); specimen in a paraffin block; specimen in a fixative.
Clinical Information
References
LOINC® Map
Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
---|---|---|---|---|---|---|
183456 | MTB-RIF NAA without AFB Cult. | 183454 | M tuberculosis complex | 14556-5 | ||
183456 | MTB-RIF NAA without AFB Cult. | 183455 | Rifampin | 33634-7 | ||
183456 | MTB-RIF NAA without AFB Cult. | 008619 | AFB Specimen Processing | 8100-0 |