Veripath Test Directory

Epic Test Name Quantiferon TB Gold
Synonyms QFT TB Gold
Description Aid in the detection of latent disease among persons at increased risk for tuberculosis (TB). Positive predictive value is less in low-risk populations. Test may be used in persons who have received BCG vaccine.
Specimen Requirements 
Container Collect three tubes contained in a special Single Patient Pack, a Grey top, Red top, and a Purple top. Tubes are available from the St.Paul Laboratory. Specimens must be in the laboratory within 16 hours from collection.
Specimen Type Blood
Preferred Collection Volume 1mL – 0.8mL
Minimum Collection Volume 1mL – 0.8mL
Collection Instructions Collect 1.0 mL of blood into each tube. Hold tubes on the needle for two to three seconds after flow ceases. Repeat tube if not close to the black fill line. Collect tubes in the following order: grey top, red top, and purple top. If a "butterfly needle" is used to collect blood, use a "purge" tube to ensure that the tubing is filled with blood prior to the tubes being used.
Specimen Handling Immediately after filling tubes, shake them ten (10) times, just firmly enough to ensure entire inner surface of tube is coated with blood, to solubilize antigens on tube wall. Do not shake over energetically as this may cause gel disruption and could lead to
aberrant results.
Rejection Criteria Over or under filled tubes. Over 16 hours from collection.
Methodology Cell Culture/Semi-Quantitative Enzyme-Linked Immunosorbent Assay
Reference Range Negative
CPT Code(s) 86480
Department Microbiology
Contact Information Ph: 214-633-4940
Turn Around Time2 – 3 days
Performed Monday – Friday
Performed by Microbiology
Notes The ability of the Quantiferon TB Gold In-Tube assay to predict the progression of latent tuberculosis infection to active tuberculosis has not been evaluated. A positive QFT result has been reported from patients infected with M. kansasii, M. marinum, and M. szulgai.
Updated/Reviewed 02/22/2018