C-6951-1
QuantiFERON ®-TB Gold (QTB) Collection & Processing Instructions
1. Obtain a QuantiFERON collection kit from the small
supply in the Outpatient Lab or from Chemistry.
2. Collect 1 mL of blood into each of 3 tubes. (Lav, Grey, Red caps)
•Tubes fill slowly
• When tube is upright, blood MUST meet the small black mark on the label.
• If butterfly needle is used, first collect other required tubes or use a “purge”
tube to remove the air and then proceed with collecting the QTB tubes.
3. Immediately shake the tubes firmly for 5 seconds (10 X).
•Entire inner surface of the tube must be coated with blood.
•Over-energetic shaking may cause gel disruption and could lead to
aberrant results.
4. Label tubes such that the “Quantiferon” band and entire specimen volume
are visible.
5. Maintain tubes at room temperature until incubation.
• It is recommended that incubation at your facility start as soon as
possible.
• Incubation must be started within 16 hour of collection.
6. Invert tubes for 5 seconds immediately before incubation.
7. Incubate all 3 tubes upright at 37°C for 16-24 hours.
• Place in microbiology 37°C walk-in incubator in labelled QTB rack
• Do Not use water bath for incubation.
• Improper incubation may cause erroneous results.
8. Centrifuge tubes for 15 minutes at 3,000 RCF (g).
9. Place all 3 tubes together in the QTB transport bag.
10. Place tubes in Quest” Refrigerate” basket in Chemistry.
(Test is interfaced)