Quantiferon TB Gold

Clinical definition of the Quantiferon TB Gold test
It is a test to detect active tuberculosis or latent tuberculosis infection. Tuberculosis is a disease caused by the bacteria Mycobacterium tuberculosis which usually attacks the lungs but can also affect other parts of the body. It may cause pulmonary tuberculosis and other infections such as those of the skin and abdomen. It is spread through the air when people who have the disease cough, sneeze, or spit.
The other widely used tests used in the diagnosis & screening of Tuberculosis infection are:

  • AFB, smear examination
  • Culture, Mycobacterium Tuberculosis
  • Mantoux test (Tuberculin skin test)
  • Mycobacterium antibody panel (TB-IgG, IgM, IgA)
  • Mycobacterium Tuberculosis by RT-PCR

Why is the Quantiferon TB Gold test done?
The QuantiFERON-TB Gold test (QFT-G) is a whole-blood test for use as an aid in diagnosing Mycobacterium tuberculosis infection, latent tuberculosis infection (LTBI) and tuberculosis (TB) disease.

What are the common signs/symptoms when the Quantiferon TB Gold test is done?
These symptoms may be diagnosed by and screened for:

  • Unexplained weight loss
  • Fatigue
  • Fever
  • Night sweats
  • Chills
  • Loss of appetite
  • Prolonged and Persistent cough
  • Blood in sputum
  • Painful breathing
  • Painful coughing

When TB severely spreads in the lungs it shows the following symptoms include:

  • Chest pain
  • Coughing up blood
  • Prolonged cough for more than three weeks

What should I do before the Quantiferon TB Gold test?

Specimen type

Specimen collection procedure

Preparatory instructions before the test *

Serum (Blood Sample)

Venipuncture - Collection of blood from a vein, usually from the arm.

No Fasting Required.

No other special preparations required.

*Subjects suffering from any illness or on oral or injectable medications are advised to consult their physician prior to requesting any tests or procedures.

How do I interpret my Quantiferon TB Gold test results?

Reference Range*


Above  0.35 IU /ml


‘*A Reference range is a set of values which helps the healthcare professional to interpret a medical test. It may vary with age, gender, and other factors. Reference ranges may also vary between labs, in value & units depending on instruments used and method of establishment of reference ranges’

Diseases/conditions related to the Quantiferon TB Gold test

  • Tuberculosis

Other tests related to the Quantiferon TB Gold test

  • Acid Fast Baciili Culture Test
  • Anti Tb
  • TB-PCR
  • Mantoux Test
  • Chest radiograph
  • Molecular testing, diagnostic
  • Mycobacteria culture
  • Atypical mycobacterial infection
  • TB skin test

Synonyms : Gamma Interferon