Quick Answer: Quantiferon Tb Gold Results Interpretation

Is QuantiFERON gold better than PPD?

The QuantiFERON (QFT) blood assay tests for tuberculosis.

Patients must get their blood drawn for a QuantiFERON exam.

However, QFT candidates receive exam results in 48-72 hours.

Compared to PPD wait times, QuantiFERON provides a sizeable advantage..

What do you do if QuantiFERON gold is indeterminate?

The options are to repeat QFT-G with a newly obtained blood specimen, administer a TST, or do neither. For persons with an increased likelihood of M. tuberculosis infection who have an indeterminate QFT-G result, administration of a second test, either QFT-G or TST, might be prudent.

What is borderline TB?

A borderline test result (T-Spot only) also indicates an uncertain likelihood of M. tuberculosis infection. A diagnosis of LTBI requires that TB disease be excluded by medical evaluation.

Is latent TB contagious?

Persons with latent TB infection are not infectious and cannot spread TB infection to others. Overall, without treatment, about 5 to 10% of infected persons will develop TB disease at some time in their lives. About half of those people who develop TB will do so within the first two years of infection.

Does QuantiFERON detect latent TB?

How do you detect a latent TB infection? There are two types of tests that can detect tuberculosis infection: the tuberculin skin test (TST), also known as the Purified Protein Derivative (PPD) test, and a blood test such as QuantiFERON-TB Gold Plus (QFT-Plus).

What is the normal range of TB?

In a healthy person whose immune system is normal, induration greater than or equal to 15 mm is considered a positive skin test. If blisters are present (vesiculation), the test is also considered positive. In some groups of people, the test is considered positive if induration less than 15 mm is present.

What does QuantiFERON-TB Gold test mean?

QuantiFERON-TB Gold (QFT) is a simple blood test that aids in the detection of Mycobacterium tuberculosis, the bacteria which causes tuberculosis (TB). QFT is an interferon-gamma (IFN-γ) release assay, commonly known as an IGRA, and is a modern alternative to the tuberculin skin test (TST, PPD or Mantoux).

What can causes a false positive Quantiferon gold?

(1) False-positive results may occur in patients with prior infection with M marinum, M szulgai, or M kansasii. Negative: No IFN-gamma response to M tuberculosis antigens was detected. Infection with M tuberculosis is unlikely.

Will QuantiFERON gold always be positive after treatment?

Since most patients remained QFT-TB positive after therapy, the test should not be used to monitor the effect of preventive therapy. Prospective studies are needed in order to determine the usefulness of IGRA tests during therapy.

Can latent TB become active after treatment?

The bacteria become inactive, but they remain alive in the body and can become active later. This is called latent TB infection. People with latent TB infection cannot spread TB bacteria to others. People who have latent TB infection can be treated to prevent developing TB disease.

How is latent TB treated?

A course of antibiotic medicine will treat latent TB. You may be given Rifampicin and Isoniazid for three months (which may be together in a tablet called Rifinah) or Isoniazid by itself for six months. Your doctor or TB specialist nurse will talk you through the treatment and answer any questions you may have.

How do you read QuantiFERON-TB Gold Plus results?

How are QFT-Plus results interpreted?Positive – suggests that TB infection is likely.Negative – suggests that TB infection is unlikely.Indeterminate – suggests the need for further investigations or repeat testing.

Can a person with TB go to work?

You need to stay home from work or school so that you don’t spread TB bacteria to other people. After taking your medicine for a few weeks, you will feel better and you may no longer be infectious to others. Your doctor or nurse will tell you when you can return to work or school or visit with friends.

Will I always test positive for TB after treatment?

Even after you finish taking all of your TB medicine, your TB skin test or TB blood test will still be positive.

What is the difference between T spot and QuantiFERON?

The T-SPOT. TB method uses separate mixtures of ESAT-6 and CFP-10 synthetic peptides as Mycobacterium tuberculosis-specific antigens, whereas QFT-GIT uses a single mixture of synthetic ESAT-6, CFP-10, and TB7.

What are the signs and symptoms of latent TB?

The Difference between Latent TB Infection (LTBI) and TB Diseasea bad cough that lasts 3 weeks or longer.pain in the chest.coughing up blood or sputum.weakness or fatigue.weight loss.no appetite.chills.fever.More items…

What if QuantiFERON-TB Gold is positive?

You have a positive Tuberculin Skin Test (TST) or QuantiFERON blood test: what does this mean? If your TST (Mantoux) or Quantiferon blood test was found to be positive, this means you have a latent TB infection, but usually not the active disease.

How long is Quantiferon TB Gold good for?

Although QFT is not recommended for confirmation of TST results, QFT can be used for surveillance <12 months after a negative tst, if the initial qft is negative.

How accurate is QuantiFERON gold test?

The specificity of QuantiFERON-TB Gold has consistently shown to be >99% in low risk individuals (12). Specificity is the probability that the test indicates a person does not have the disease (or infection) when that person is disease free.

What happens if you test positive for tuberculosis?

A positive TB test result means only that TB bacteria has been detected. It does not indicate whether the person has active TB or a latent infection. This requires additional testing. TB disease can be diagnosed by medical history, physical examination, chest X-ray, and other lab tests.