Department
Chemical Pathology
Delphic Registration Code (Alpha Code)
QFAU
Test Code (Numeric Code)
4120
Laboratory Handling
Phlebotomy
Samples collected in the morning by PHLEBOTOMIST only
Laboratory
Only QuantiFERON tubes can be used
Sample Stability
.
Synonyms
QTB Gold Test
Turnaround Time
1 week
Samples collected in the morning by phlebotomists only, Monday to Friday
Specimen Type
- Whole Blood
Specimen Requirements
Tube/Container Type:
Preferred
- QTGB Nil (Grey Cap)
- QTBG TB1 antigen (Green Cap)
- QTBG TB2 antigen (Yellow Cap)
- QTBG Mitogen (Purple Cap)
Preferred Sample Volume (ml)
1
Minimum Sample Volume (ml)
1
Paediatric Specimen Requirements
Tube/Container Type:
Preferred
- QTGB Nil (Grey Cap)
- QTBG TB1 antigen (Green Cap)
- QTBG TB2 antigen (Yellow Cap)
- QTBG Mitogen (Purple Cap)
Pre-testing Requirements
This test is not routinely recommended if active tuberculosis is under investigation. Please collect samples for mycobacterial culture +/- TB PCR instead.
Additional Specimen Information
Four tubes should be collected on all patients in the following order:
- Nil control (grey cap)
- TB antigen 1 (green cap)
- TB antigen 2 (yellow cap)
- Mitogen control (purple cap)
1 mL of blood must be collected into each tube (drawn by vacuum which may be slow) indicated by the black mark on the side of the tube.
Thorough mixing is very important. Tubes should be mixed by turning the tube end-over-end 8 to 10 times ensuring that the entire inner surface of the tube has been coated with the blood.
A discard tube is required when using a butterfly needle.
Last updated: 17/04/2026