Specimen Information

Special collection, incubation, and centrifuge procedures must be followed.  This test uses specialized blood collection tubes.  For complete blood collection and specimen transport instructions, refer to "Quantiferon TB Gold Plus Collection and Processing Instructions" under Resources.

Collection Instructions:

1.  All 4 tubes (Grey, Green, Yellow, and Lavender) contain Sodium Heparin and therefore must be drawn after any tests ordered for a SST (i.e. follow typical order of draw protocol).

2.  There is no order of draw within the set.

3.  If a butterfly is utilized for collection and no other testing is required for the patient, a waste tube must be used before filling the first quantiferon tube.

4.  Each tube must be filled to the fill line before the tubes are inverted.

5.  Once collected, immediately invert all 4 tubes 10 times to ensure proper mixing.  The entire inner surface of the tube must be coated with blood.  Frothing of the blood is expected.  Avoid shaking the blood vials vigorously.  Doing so could cause disruption to the gel and interfere with test results.

6.   Tubes must be incubated at  37°C as soon as possible and within 16 hours of collection.  Prior to incubation, maintain tubes at room temperature.

7.   Incubate tubes for 16-24 hours and then centrifuge for 15 minutes at 2000-3000 RCF(g) to separate cells from the plasma.  

8.  NOTE:  Incubation and centrifugation of the QFT-Plus tubes is performed in the lab.