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Based on test results, provide follow-up evaluation and treatment as needed.Schedule a follow-up appointment for the patient to receive test results.Draw a blood sample from the patient according to the test manufacturer’s instructions.What are the steps in administering an IGRA test?Ĭonfirm arrangements for testing in a qualified laboratory, and arrange for delivery of the blood sample to the laboratory in the time the laboratory specifies to ensure testing of samples with viable blood cells. Limited data on the use of IGRAs to predict who will progress to TB disease in the future.Errors in collecting or transporting blood specimens or in running and interpreting the assay can decrease the accuracy of IGRAs.Blood samples must be processed within 8-30 hours after collection while white blood cells are still viable.What are the disadvantages and limitations of IGRAs? Prior BCG (bacille Calmette-Guérin) vaccination does not cause a false-positive IGRA test result.Does not boost responses measured by subsequent tests.Results can be available within 24 hours.Requires a single patient visit to conduct the test.Separate mixtures of synthetic peptides representing ESAT-6 & CFP-10 Single mixture of synthetic peptides representing ESAT-6, CFP-10 & TB7.7. Process peripheral blood mononuclear cells (PBMCs) within 8 hours, or if T-Cell Xtend ® is used, within 30 hours Table1: Differences in Currently Available IGRAs Table1: Differences in Currently Available IGRAs

The antigens, testing methods, and interpretation criteria for IGRAs differ (see Table 1). To conduct the tests, fresh blood samples are mixed with antigens and controls. tuberculosis will release interferon-gamma (IFN-g) when mixed with antigens (substances that can produce an immune response) derived from M. White blood cells from most persons that have been infected with M. IGRAs measure a person’s immune reactivity to M. QuantiFERON®-TB Gold In-Tube test (QFT-GIT).Food and Drug Administration (FDA) are commercially available in the U.S: Two IGRAs that have been approved by the U.S. They do not help differentiate latent tuberculosis infection (LTBI) from tuberculosis disease.

Interferon-Gamma Release Assays (IGRAs) are whole-blood tests that can aid in diagnosing Mycobacterium tuberculosis infection. Interferon-Gamma Release Assays (IGRAs) – Blood Tests for TB Infection What are they?