QFT-Plus Workflow
TB Management

Workflow

Screen for TB with confidence using QFT-Plus

QuantiFERON-TB Gold Plus (QFT-Plus) is a simple blood test that accurately identifies people infected with M. tuberculosis (MTB), the causative agent of TB (tuberculosis). QFT-Plus is a modern alternative to the 110-year-old tuberculin skin test (TST).

The QFT-Plus assay

The QFT-Plus assay is an in-vitro diagnostic laboratory test that aids in the indirect detection of infection with MTB. It uses human whole blood, with patented assay technology based on the measurement of Interferon-gamma (IFN-γ) secreted from stimulated T-cells previously exposed to MTB. It is a straightforward laboratory test that involves the following steps:
  • Step 1
    Blood collection

  • Step 2
    Mixing of tubes

  • Step 3
    Incubation

  • Step 4
    ELISA

  • Step 5
    Calculation of results

TB testing workflow with QFT-Plus blood collection options 

Accurate QuantiFERON-TB Gold Plus (QFT-Plus) test results start with proper blood sample handling. Subsequently, incubation of the blood occurs in the tubes for 16 to 24 hours, after which, plasma is harvested and tested for the presence of IFN-γ produced in response to the peptide antigens.
The QFT-Plus test can be performed in either of the following ways, depending on the blood-collection process: 

Option 1: Direct blood draw into QFT-Plus blood collection tubes

Collect 1 ml of whole blood directly into each of four QFT-Plus blood collection tube and hold at room temperature for up to 16 hours prior to incubation.

Option 2:  Blood draw into a single lithium-heparin tube
Draw at least 5 ml of blood into a single blood collection tube containing lithium heparin as the anticoagulant. Blood collected into a single lithium-heparin tube may be stored at room temperature or refrigerated for up to 53 hours prior to transfer to QFT-Plus tubes and incubation.

*QuantiFERON-TB Gold Plus Blood Collection Tubes by QIAGEN and LIAISON Analyzer by DiaSorin.

LIAISON® is a registered trademark of DiaSorin.

QFT-Plus is an in vitro diagnostic aid for detection of Mycobacterium tuberculosis infection. QFT-Plus is an indirect test for M. tuberculosis infection (including disease) and is intended for use in conjunction with risk assessment, radiography, and other medical and diagnostic evaluations. QFT-Plus Package Inserts, available in multiple languages, as well as up-to-date licensing information and product-specific disclaimers can be found at www.QuantiFERON.com.