Quantiferon TB Gold
The QuantiFERON collection tubes, as supplied by Phlebotomy services must be used. No other tubes are acceptable.Collect 1mL blood (up to the black mark) into each of the four Quantiferon Gold tubes supplied. Immediately after filling the tubes, shake them 10 times to ensure the entire inner surface of the tube is coated with blood.
Samples must be incubated within 16 hours of collection.
Prior to incubation store tubes at room temperature.
After incubation tubes may be held at 4-27°C for three days prior to centrifugation.
After centrifugation samples must be refrigerated.
Incubated and centrifuged tubes must be sent chilled.
Un-incubated tubes should be sent at ambient temperature. They must reach the laboratory within 16 hours of collection.
Please indicate on specimen bag whether samples have been incubated or not.
Positive, Negative, Indeterminate, Equivocal.
QuantiFERON-TB Gold IT is an indirect test for M.tuberculosis infection (including disease) and is intended for use in conjunction with risk assessment, radiography and other medical and diagnostic evaluations.
The test has a very limited role in the diagnosis of TB. It should not be performed except in screening for latent TB infection in patients going on biologic therapy, or starting other immunosuppressants, or in the screening of TB contacts (see Guidelines for Tuberculosis Control in New Zealand 2019) in conjunction with Public Health)
The following approaches are recommended for different groups:
Contact screening for latent TB (LTBI):
Healthcare worker screening for LTBI:
Refugee screening for LTBI:
Screening for LTBI in immune-compromised people
An IGRA is particularly recommended in the following: