A positive tuberculosis (TB) blood test, also known as an Interferon Gamma Release Assay (IGRA), indicates that you likely have TB germs in your body. However, it doesn't differentiate between latent TB infection and active TB disease. Further tests are needed to determine whether you have active TB disease.
Here's what to know:
- TB blood test: This test measures your immune response to TB bacteria. A positive result suggests that you have been exposed to TB and have developed an immune response.
- Latent TB infection: In this case, the TB bacteria are inactive and don't cause symptoms. However, you can still transmit the bacteria to others.
- Active TB disease: In this case, the TB bacteria are active and causing symptoms like coughing, fever, weight loss, and night sweats.
If you have a positive TB blood test, your healthcare provider will likely order additional tests to determine if you have active TB disease. These tests might include:
- Chest x-ray: This can help detect signs of active TB in your lungs.
- Sputum culture: This involves collecting a sample of your phlegm to test for the presence of TB bacteria.
A positive TB blood test is not a definitive diagnosis of active TB disease, but it is an important indicator that further investigation is necessary.
