Specimen Requirements

QuantiFERON-QTB Gold In-Tube Collection Kit - Obtain collection kit from the laboratory

Collection Instructions:

1. For each subject, collect 1mL of blood by venipuncture directly into each of the 4 QFT blood collection tubes. This procedure should be performed by a trained phlebotomist.

• As 1mL tubes draw blood relatively slowly, keep the tube on the needle for 2-3 seconds once the tube appears to have completed filling, to ensure that the correct volume is drawn.
• The black mark on the side of the tubes indicates the 1mL fill volume. QFT blood collection tubes are manufactured to draw 1mL + 10% and perform optimally within the range of 0.8 to 1.2mL. If the level of blood in any tube is not close to the indicator line, it is recommended to obtain another blood sample or to collect blood via a syringe as described below. Under or over-filling of the tubes outside of the 0.8 to 1.2mL range may lead to erroneous results.
• Standard QFT blood tubes have been validated to draw between 0.8mL and 1.2mL at altitudes from sea-level to 2,650 feet.
• If a “butterfly needle” is being used to collect blood, a “purge” tube should be used to ensure that the tubing is filled with blood prior to the QFT tubes being used.

2. Immediately after filling the tubes, shake them ten (10) times just firmly enough to ensure the entire surface of the tube is coated with blood, to dissolve antigens on tube walls. 

• Tube temperature should be between 17°C to 25°C (63°F to 77°F) at the time of blood tube filling.
• Overly vigorous shaking may cause gel disruption and could lead to aberrant results.

3. Label tubes appropriately.

• Ensure each tube (Nil, TB1 Antigen, TB2 Antigen, Mitogen) is identifiable by its label or other means once the cap is removed.