Understanding Lab Tests for Latent tuberculosis infection

Latent tuberculosis infection (LTBI) occurs when a person is infected with Mycobacterium tuberculosis bacteria but does not have active disease. People with LTBI have no symptoms, are not infectious, but carry dormant bacteria that could potentially develop into active tuberculosis in the future. Specialized blood tests are essential for detecting this hidden infection.

Recommended Test

Why Testing for Latent TB is Important

Since latent TB infection produces no symptoms and cannot be detected through physical examination alone, laboratory testing is the primary method for diagnosis. Early detection allows for preventive treatment that can significantly reduce the risk of developing active tuberculosis disease, which is contagious and potentially life-threatening.

Understanding Your Results

A positive QuantiFERON test indicates exposure to TB bacteria and the presence of latent infection. However, it cannot distinguish between latent and active TB, so additional evaluation by a healthcare provider is necessary to rule out active disease. A negative result generally indicates no TB infection, though recent exposure or certain medical conditions may affect test accuracy.

Important Considerations

The information here is for educational purposes only and is not a substitute for professional medical advice. Always consult with a healthcare provider for diagnosis and treatment. If you test positive for latent TB, your doctor will evaluate whether preventive treatment is recommended based on your individual risk factors.

References

• https://www.cdc.gov/tb/topic/testing/latentinfection.htm
• https://www.mayoclinic.org/diseases-conditions/tuberculosis/diagnosis-treatment/drc-20351256
• https://medlineplus.gov/tuberculosis.html