ARUP's Laboratory Test Directory

QuantiFERON®-TB Gold In Tube : 0051729

Mnemonic: QFTG-TB IT

Methodology: Cell Culture/Semi-Quantitative Enzyme-Linked Immunosorbent Assay
Performed: Sun-Sat
Reported: 1-2 days
Specimen Required: Collect: At altitudes from sea level to 2,650 feet: QuantiFERON®-TB (Standard) Gold In-Tube collection kit.
At altitudes from 2,650-3,350 feet: QuantiFERON®-TB (Standard) Gold In-Tube collection kit.
At altitudes from 3,350-6,150 feet: QuantiFERON®-TB (High Altitude) Gold In-Tube collection kit.
At altitudes above 6,150 feet: QuantiFERON®-TB (High Altitude) Gold In-Tube collection kit.

Specimen Preparation: At altitudes from sea level to 2,650 feet: Whole blood directly into each of the three tubes in the QuantiFERON®-TB (Standard) Gold In-Tube collection kit (ARUP
supply #45112) available online through eSupply using ARUP Connect™ or contact ARUP Client Services at (800) 522-2787.
At altitudes from 2,650-3,350 feet: Collect 3 mL whole blood using a syringe. Transfer 1 mL (Min: 0.8 mL, Max 1.2 mL) to each of the three tubes in QuantiFERON®-TB
(Standard) Gold In-Tube collection kit (ARUP supply #45112).
At altitudes from 3,350-6,150 feet: Whole blood directly into each of the three tubes in the QuantiFERON®-TB (High Altitude) Gold In-Tube collection kit (ARUP
supply #46261) available online through eSupply using ARUP Connect™ or contact ARUP Client Services at (800) 522-2787.
At altitudes above 6,150 feet: Collect 3 mL whole blood using a syringe. Transfer 1 mL (Min: 0.8 mL, Max 1.2 mL) to each of the three tubes in QuantiFERON®-TB (High
Altitude) Gold In-Tube collection kit (ARUP supply #46261).
Tubes should be between 17°C and 25°C (63°F to 77°F) at the time of blood filling.
Immediately after filling tubes, shake them ten (10) times just firmly enough to ensure the entire inner surface of the tube is coated with blood, to solubilize antigens on
tube walls. Over-energetic shaking may cause gel disruption and could lead to aberrant results.
After mixing, incubate upright at 37° C for 16-24 hours (within 16 hours of collection).
After incubation, centrifuge for 15 minutes at 2000-3000 RCF (g).
After centrifugation, transport entire contents in each of the 3 original collection tubes.

Storage/Transport Temperature: Refrigerated.

Remarks: Further information on mixing QuantiFERON®-TB Gold In-Tube collection tubes and an instructional video can be found at: http://www.aruplab.com/Specimen-Handling/SpecialSpecimenCollection/quantiferon.jsp

Unacceptable Conditions: Specimens that have not been incubated and centrifuged.

Stability (collection to initiation of testing): After incubation and centrifugation: Ambient: 2 hours; Refrigerated: 4 weeks; Frozen: 4 months
Reference Interval:
 
QuantiFERON®-TB Gold In Tube
Effective November 19, 2012
Components Reference Interval
Quantiferon TB Gold In-Tube Negative
Quantiferon TB minus NIL 0.34 IU/mL or less
Quantiferon MITOGEN minus NIL No reference interval
Quantiferon NIL No reference interval

Interpretive Data: The QuantiFERON® software interprets the three values, NIL, MITOGEN minus NIL (MITOGEN-NIL), and TB minus NIL (TB-NIL), to provide the qualitative result (Negative, Positive, or Indeterminate). The NIL value represents nonspecific reactivity detected within the patient specimen. The MITOGEN-NIL value serves as the positive control for the patient specimen, demonstrating successful lymphocyte activity. The TB-NIL value represents lymphocyte reactivity specifically stimulated by the TB antigen. An overall Negative result does not completely rule out TB infection. An overall Positive result does not differentiate active from latent tuberculosis.
Note: The ability of the QuantiFERONGold In-Tube assay to predict the progression of latent tuberculosis infection to active tuberculosis has not been evaluated.  For questions about collection and stability of sample please call Microbial Immunology 1 at (801) 583-2787, extension 2270. 

Further information on mixing QuantiFERONGold In-Tube collection tubes and an instructional video can be found at www.aruplab.com/quantiferon
CPT Code(s): 86480
Cross References: Interferon-Gamma Release Assay for Tuberculosis (QuantiFERON®-TB Gold In Tube) , Latent Tuberculosis Infection (LTBI) (QuantiFERON®-TB Gold In Tube)