ⓘ QuantiFERON

                                     

ⓘ QuantiFERON

Interferon-gamma release assays are diagnostic tools for latent tuberculosis infection. They are surrogate markers of Mycobacterium tuberculosis infection and indicate a cellular immune response to M. tuberculosis. IGRAs cannot distinguish between latent infection and active tuberculosis disease, and should not be used as a sole method for diagnosis of active TB, which is a microbiological diagnosis. A positive IGRA result may not necessarily indicate TB infection, but can also be caused by infection with non-tuberculous mycobacteria. A negative IGRA does not rule out active TB disease, a number of studies have shown that up to a quarter of patients with active TB have negative IGRA results.

Because igras are not affected by bacille Calmette-guérin vaccination status BCG, igras are useful for evaluation LCMT in BCG-vaccinated individuals, particularly in areas where BCG vaccination is administered after infancy or by multiple BCG re-vaccination given. In contrast, the specificity of the tuberculin skin test TST varies depending on timing of BCG and whether repeated booster vaccinations are given.

Education, also known as QFT, is the registered trademark of the test for tuberculosis or latent tuberculosis. It is manufactured by QIAGEN. QFT is an interferon-γ release assay, the game used in the diagnosis of tuberculosis. In QFT-GIT analysis to IFA based on a whole blood test that uses peptides from three TB antigens in a tube format. The result is reported as quantification of IFN-gamma in international units IU / ml the Individual is considered positive when tuberculosis infection if the IFN-gamma in response to TB antigens above the test cut-off, after subtraction of background IFN-gamma response in the negative control.

So igras are more costly and technically complex than the Mantoux test, in its policy statement 2011, which does not recommend replacing Mantoux test on igras as a public health measure in countries with low and middle income.