QUANTIFERON-TB GOLD

Collect  1.0 ml of whole blood DIRECTLY into each tube of the QuantiFERON® TB Gold Collection Kit.

Collect by venipuncture only - DO NOT collect via line.   

QuantiFERON® TB Gold Collection Kit:  (3 tubes – Nil Control, Mitogen Control, TB Antigen)  

1.0 ml required per tube; Fill tubes to the black line on the side of the tube label = 1.0 ml

Maintain tubes at room temperature (22°C ± 5°C).  Tubes MUST be transported to the laboratory within 16 hours of collection. DO NOT transport on ice or refrigerated.

Collect  1.0 ml of whole blood DIRECTLY into each tube of the QuantiFERON® TB Gold Collection Kit:  (3 tubes – Nil, Mitogen, TB Antigen)  

DO NOT overfill tubes. Fill tubes to the black line on the side of the tube label = 1.0 ml.

Collect by venipuncture only - DO NOT collect via line. 

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.

Up to 16 hours following specimen collection

Tubes that are overfilled/underfilled, received greater than 16 hours following collection, or received refrigerated or on ice are unacceptable and will be rejected.

NIL     TB Antigen minus      Mitogen minus    Result       Interpretation    
IU/mL        NIL IU/mL           NIL IU/mL                              
================================================================================
<=8.0    >=0.35 and >=25%
         of Nil value              Any        Positive        M. tuberculosis
                                                              infection likely
================================================================================
<=8.0    <0.35                     >=0.5      Negative        M. tuberculosis
                                                              infection not
                                                              likely
<=8.0    >=0.35 and <25%           >=0.5      Negative
         of Nil value
================================================================================
<=8.0    <0.35                     <0.5       Indeterminate    Results are
                                                               Indeterminate for
<=8.0    >=0.35 and <25%           <0.5       Indeterminate    TB Antigen
         of Nil value                                          responsiveness

>8.0       Any                      Any       Indeterminate
================================================================================

1 week

Interferon gamma release assay (ELISA)

Clinical Microbiology Laboratory

QFT

Detection of latent disease among persons at increased risk for TB

86480 (Tuberculosis test, cell mediated immunity measurement of gamma interferon antigen response)

Test results are calculated in accordance with an FDA-approved algorithm run on QuantiFERON(R) software.
The QuantiFERON(R) TB Gold (in Tube) assay is intended for use as an aid in diagnosis of TB infection. Negative results suggest that there is not TB infection. In patients with high suspicion of exposure, a negative test should be repeated. A positive test indicates infection with Mycobacterium tuberculosis. Among individuals without tuberculosis infection, a positive test may be due to exposure to M. kansasii, M. szulgai, or M. marinum. As with any screening test, positive results must be interpreted with caution and in context with associated risk factors. Diagnosing or excluding tuberculosis disease and assessing the probability of latent TB infection requires a combination of epidemiological, historical, medical and diagnostic findings that should be taken into account when interpreting QuantiFERON(R) TB results.
For further information, refer to http://www.cdc.gov/mmwr/pdf/rr/rr5905.pdf
Strict adherence to the proper collection and processing of QTF specimen tubes is essential in obtaining proper stimulation of cells for the production of interferon gamma.