9/28/2010 QuantiFERON Gold In-Tube: The Basics of Getting Started - PDF document

9/28/2010 QuantiFERON Gold In-Tube: The Basics of Getting Started Richard Oatis Supervisor, Mycobacteriology State of Maryland Department of Health and Mental Hygiene D t t f H lth d M t l H gi Labs Administration 201 West Preston Street Baltimore, MD 21201 (410) 767-6130 oatisr@dhmh.state.md.us What is QuantiFERON Gold In-Tube? � An interferon-gamma release assay whereby whole blood is exposed to proteins specific to M. tb. complex (but not BCG) to test for latent TB infection not BCG) to test for latent TB infection. � The test requires 1 mL of blood to be drawn into each of three specialized collection tubes: a blank (Nil) tube, the test (Antigen) tube, and a positive (Mitogen) tube. Why Do I Need QuantiFERON? � Foreign-born populations, especially those vaccinated with BCG. � Transient populations (such as the homeless) where compliance with a return visit to read a TST may prove difficult. 1

9/28/2010 QuantiFERON vs. T-Spot � T-Spot may have slightly increased sensitivity over QuantiFERON. � QuantiFERON requires less specialized equipment, training and labor hours than T-Spot, and can be easily implemented in almost any serology lab. Basic Equipment Needed � 37°C incubator � Blood centrifuge � Microplate shaker Microplate shaker � Room temperature incubator (optional) � Microplate washer � Microplate reader/PC � Pipettes and pipette tips � Distilled water Cellestis Components � ELISA Kit – Must be stored between 2°C and 8°C (refrigerated). � Blood Tubes – Can be stored between 4°C and 25°C (room temperature). 2

9/28/2010 Blood Collection is Specialized � Tubes should be drawn in a specific order (Nil, Antigen, Mitogen). � Blood must be drawn exactly to the fill li line on collection tubes (1 mL). ll i b (1 L) � Tubes must be shaken vigorously at time of draw and incubation. � Time of blood draw must be recorded accurately and communicated to the testing lab. Blood tubes must be incubated at 37°C within 16 hours � Multiple testing sites. � Specialized couriers/receiving for blood specimens. � Designated draw times for patient specimens. � Perform 37°C incubation at draw site. Reporting Test Results Do you report actual quantitative values to clinicians or just the interpretive results? 3

9/28/2010 Further Resources QuantiFERON package insert: http://www.cellestis.com/IRM/Company/ShowPage.aspx?CPID=1171 T-Spot package insert: http://www.oxfordimmunotec.com/96-UK CDC Resources: Guidelines for IGRA testing: http://www.cdc.gov/tb/publications/guidelines/Testing.htm Fact Sheet: http://www.cdc.gov/tb/publications/factsheets/testing/IGRA.htm 4