QuantiFERON-TB Gold Plus, Blood
Use
The QuantiFERON-TB Gold Plus (QFT-Plus) test is an interferon-gamma release assay (IGRA) that assesses the cell-mediated immune response to Mycobacterium tuberculosis complex antigens, ESAT-6 and CFP-10, by measuring IFN-gamma levels in plasma. It is used to detect latent tuberculosis infection (LTBI), which is a non-communicable, asymptomatic condition that may progress to active tuberculosis disease, especially in immunosuppressed patients. This test helps in assessing the risk and initiating medical treatment to prevent progression to active disease.
Special Instructions
This test is not recommended for the diagnosis of active tuberculosis infection. It is recommended to use an aid for detecting latent TB infection. It must be used in conjunction with other clinical evaluations, including risk assessment and radiography.
Limitations
A negative QuantiFERON-TB Gold Plus result does not exclude Mycobacterium tuberculosis infection or tuberculosis disease. False-negative results can occur due to improper specimen collection or handling, and other immunological factors. Positive results may be due to infections with Mycobacterium kansasii, Mycobacterium szulgai, or Mycobacterium marinum. The test should not be the sole basis for determining tuberculosis infection.
FDA ApprovedNew York Approved
Methodology
Immunoassay (CLIA)
Biomarkers
LOINC Codes
- 71775-1
- 71773-6
- 64084-7
- 88517-8
- 71774-4
- 71776-9
Result Turnaround Time
2-5 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
4 mL
Minimum Volume
1 mL per tube (4 tubes)
Container
QTBKIT
Collection Instructions
Special collection, incubation, and centrifugation procedures must be followed. For blood collection options, see Mycobacterium tuberculosis Infection Determination by QuantiFERON-TB Gold Plus Collection and Processing Instructions.
Patient Preparation
Perform TB symptom screening on all healthcare personnel or patients prior to COVID-19 mRNA vaccination, and if possible, collect blood prior to vaccination.
Storage Instructions
Refrigerated
Causes for Rejection
Specimen submitted not following kit guidelines, gross hemolysis, gross lipemia, gross icterus
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 28 days |