Test Category: Immunology
Investigation Name:QuantiFERON-TB Gold Plus (QFT)
Alias or Abbreviation:QFT, IGRA, Latent TB
Intro:
Indication:Latent M. tuberculosis infection.
Further information:
QuantiFERON is an ELISA based interferon gamma release assay. This is similar to the TB ELISpot and is particularly suitable for screening large numbers of healthy people in contact tracing or health care worker screening. This test is not suitable for patients on immunosuppressive drugs or who have an immunodeficiency e.g. HIV. TB ELISpot should be performed in these circumstances. The QuantiFERON assay cannot distinguish between latent and active TB infection.
Pathology Laboratory:Immunology laboratory
Requestable Seperately?Yes
Minimum Sample Volume:0.9 – 1.1mL per tube
Expected Turnaround Time:Frequency: Daily Target: 3 days
Test Code:IGRA
Sample Type:
Blood to be collected into the QFT-TB Gold Blood collection tubes only (4 tubes)Complex Reference Range:Positive/ Negative/ Indeterminate
Collection Conditions / Other Information:Transport - must be received in the laboratory within 16 hours of venepuncture
Referred to Another Laboratory?No
Storage Requirements:Ambient temperature
NPEX / PDF Reporting Available:Yes
EQA Scheme:Yes
Further information:Must be received by the laboratory within 16hrs of venepuncture. Sample volumes must be within 0.9 –
1.1mL per tube. Samples will only be accepted Monday - Thursday.
For guidance see details in IMM/FOR/3 Guide to taking a TB IGRA sample using the QuantiFERON-TB Gold Plus Blood collection tubes.
Lead Contact Details:rwh-tr.bcpsimmunologyclinicalqueries@nhs.net
Email Address For Chasing Results:rwh-tr.ImmunologyLab@nhs.net
Methodology:ELISA
UKAS Reference Number:9580 (recommended)
Site Sample Tested:Immunology, New Cross Hospital, Wolverhampton
Contact Number:01902 695 279 or Ext 85279
