Collect 1mL of blood by venipuncture directly into each of the QuantiFERON-TB Gold Plus (QFT-PLUS) blood collection tubes using only a vacutainer or syringe. Four tubes must be collected for each patient: gray cap tube (Nil control), green cap tube (TB1 antigen), yellow cap tube (TB2 antigen) and purple cap tube (Mitogen Contol). It is recommended to draw in the order of gray, green, yellow, purple. As 1 ml tubes draw blood relatively slowly, keep the tube on the needle for 2-3 seconds once the tube appears to have completed filling. This will ensure the correct volume is drawn.  If a “butterfly needle” is being used to collect blood, use a "purge tube" to ensure that the tubing is filled with blood prior to use of the QFT-Plus blood collection tubes. The black indicator line on the side of the tube indicates the correct fill volume; the tubes must not be filled above or below this line. If one tube is a short draw tube, the one tube can be redrawn immediately. All four tubes do not need to be redrawn. 
Mix the tubes after the draw by shaking 10 times, just firmly enough to ensure that the entire inner surface of each tube is coated with blood to solubilize antigens on tube walls. Over-energetic shaking may cause gel disruption and could lead to aberrant results.

The collection date and time is required on the specimen tubes. If adding a barcode label, please do not cover the top of the TB Gold IT color coded label which is necessary for the lab to identify tube type. Transport immediately and store at room (ambient) temperature. DO NOT CENTRIFUGE, REFRIGERATE, PLACE ON ICE, OR FREEZE THE BLOOD SAMPLES.

These special tubes are available from Laboratory Specimen Receiving for hospital sites or Regional Pathology Services.

Labeling: Two patient identifiers (ie: patient first and last name, date of birth) and the collection date and time are required. If using bar codes do not cover the portion of the label with the black fill line.  Indicate if specimens are incubated prior to transport to lab.

Specimens > 16 hours old, no exceptions; centrifuged, refrigerated, frozen; collect time and date is not recorded on specimen; use of any blood collection tubes other than the QFT-Plus blood collection tubes; samples outside the acceptable fill range (black indicator line).

Incubated:  specimens not incubated within 16 hours of collection, incubated >24 hours, not received by the laboratory within 3 days (unless centrifuged), frozen, incorrectly labeled tubes, use of any blood collection tubes other than the QFT-Plus blood collection tubes, samples outside the acceptable fill range (black indicator line).

Specimens must be sent to the laboratory immediately so they can be processed within 16 hours of collection. Specimens can be received in the Microbiology Laboratory at any time 24 hrs/day; 7 days/week. Please contact Regional Pathology Services at 1-800-334-0459 if courier service is needed for outpatient specimens.

Specimens may be incubated before submission: 37°C for 16-24 hours. Label tubes as "incubated".
Once incubated, uncentrifuged tubes are acceptable up to 3 days post incubation at 4°-27°C. For longer transport, centrifuge tubes for 15 minutes at 3000g and send refrigerated.
 

Stability: Non-incubated specimens.  Ambient.  Samples must be received by the lab < 16 hours of collection.

Incubated: uncentrifuged specimens: ambient or refrigerated.  Specimens must be received in the lab within 3 days after incubation.  Specific incubation instructions required.  If transport time after incubation will be greater than three days, centrifuge sample (15 minutes at 3000g) and send refrigerated.

Microbiology/Serology.

Note: Routine testing is performed daily. Samples require an incubation period of at least 16 hours before processing for testiong. 

Microbiology/Serology.

Note: Routine testing is performed daily. Samples require an incubation period of at least 16 hours before processing for testiong. 

Chemiluminescence Immunoassay

Results are reported by 4 pm on Tuesday and Friday.

Negative < 0.35 IU/ml
Positive >= 0.35 IU/ml