What tests are done for latent TB?
The main ways to diagnose LTBI are by placing a tuberculin skin test (TST) on the forearm or by getting a TB blood test, in addition to obtaining a chest radiograph (x-ray) if either one of these tests is positive. One-third of the world’s population has LTBI. The TB germs are dormant (asleep) in the body.
How is TB diagnosed?
TB disease can be diagnosed by medical history, physical examination, chest x-ray, and other laboratory tests. TB disease is treated by taking several drugs as recommended by a health care provider. If a person does not have TB disease, but has TB bacteria in the body, then latent TB infection is diagnosed.
What is the gold standard for TB diagnosis?
Nucleic Acid Amplification (NAA) Test Culture remains the gold standard for laboratory confirmation of TB disease, and growing bacteria are required to perform drug-susceptibility testing and genotyping.
What is the normal range of TB?
According to national guidelines, borderline-range data were categorized as negative (<0.20 IU/ml), borderline negative (0.20 to 0.34 IU/ml), borderline positive (0.35 to 0.99 IU/ml), and positive (≥1.0 IU/ml) based on the interferon gamma level (15).
What are the symptoms of latent TB?
The Difference between Latent TB Infection (LTBI) and TB Disease
- a bad cough that lasts 3 weeks or longer.
- pain in the chest.
- coughing up blood or sputum.
- weakness or fatigue.
- weight loss.
- no appetite.
Is latent TB Serious?
Your Have Latent Tuberculosis Infection (LTBI) TB disease is very serious. TB disease can kill you. Even if you feel okay now, you must take the medicine your health care provider has prescribed and follow your health care provider’s instructions.
What are the 3 stages of TB?
There are 3 stages of TB—exposure, latent, and active disease. A TB skin test or a TB blood test can diagnose the disease.
Is TB gold test accurate?
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 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.