The Mantoux skin test is a diagnostic tool used to detect tuberculosis (TB) infection by measuring the immune response to a purified protein derivative (PPD) injected under the skin.
The Mantoux test, also called the tuberculin skin test (TST) or PPD test, is used to determine whether a person has been exposed to Mycobacterium tuberculosis, the bacteria that cause TB. It is primarily a screening tool for latent TB infection, where the bacteria are present but inactive, and can also help identify active TB disease. The test does not differentiate between latent and active TB; additional tests, such as chest X-rays or blood tests, are required for confirmation.
Interpretation of Results
- Positive test: Indicates TB infection, but not necessarily active disease. The threshold for positivity varies depending on risk factors, such as immunosuppression, recent exposure, or BCG vaccination history.
- Negative test: Suggests no TB infection, though very recent exposure or immunosuppression may yield false negatives.
Follow-up: Individuals with a positive test usually require a chest X-ray to rule out active TB before starting treatment for latent TB infection.
Mantoux test - Wikipedia