A Tine test is a type of tuberculin skin test (TST) used to help diagnose tuberculosis (TB). It involves multiple punctures of the skin with a tine containing tuberculin, a purified protein derivative from the bacteria that causes TB. This method differs from the more commonly used Mantoux test, which uses a single injection of tuberculin. While similar to the Heaf test, the Mantoux test is generally preferred today. A positive Tine test indicates the possible presence of TB bacteria in the body. The results are interpreted by measuring the size of the resulting reaction at the puncture site.
How the Tine Test Works
- A special device with multiple tines, coated in tuberculin, is used to prick the skin.
- The test looks for a reaction to the tuberculin, indicating prior exposure to TB.
- The size of the reaction (induration) is measured 48-72 hours later to determine if the test is positive or negative.
Comparison to Other TB Tests
The Tine test, while less commonly used than the Mantoux test, offers a multiple-puncture approach for TB diagnosis. Studies have shown varying levels of agreement between the Tine and Mantoux tests, with some suggesting the Tine test may show a higher rate of positive results, particularly in individuals who have received the BCG vaccine. This is evidenced by the comparison studies performed, showing a higher positive test rate for the Tine test than the Mantoux. Other methods for TB testing include blood tests like Interferon Gamma Release Assays (IGRAs).
Importance and Context
TB testing, whether using the Tine, Mantoux, or blood tests, is crucial for identifying individuals who may have latent TB infection (LTBI) or active TB disease. Early diagnosis is essential for effective treatment and preventing the spread of the disease. The CDC emphasizes the importance of TB testing and treatment to prevent active TB disease, which can be fatal if left untreated. Testing is often recommended for individuals with symptoms suggestive of TB or those at higher risk due to exposure or other factors. Various healthcare systems might refer to TB testing under different names, including PPD, Mantoux, TST, or Tine tests.
