Which test is commonly used to diagnose tuberculosis besides sputum tests?

The Tuberculin skin test, also known as the Mantoux test, is commonly used for screening and diagnosing tuberculosis (TB). It works by injecting a small amount of purified protein derivative (PPD) into the skin, and after 48 to 72 hours, the reaction is assessed. A positive reaction indicates that the person has been exposed to the TB bacteria, although it does not confirm that an active infection is present.

This test is particularly valuable in its ability to identify individuals who have been infected with the Mycobacterium tuberculosis bacteria. It is especially useful in high-risk populations, such as those with weakened immune systems or those who have been in close contact with TB patients. While not definitive for diagnosing active TB (as it may also react in cases of past infections or other mycobacterial diseases), it is a crucial tool in the initial screening process.

Other tests such as blood cultures, chest X-rays, and CT scans can provide additional information or help in confirming an active infection but are not typically used as first-line diagnostic tests in a manner comparable to the Tuberculin skin test. The chest X-ray may identify lung abnormalities but cannot confirm TB by itself, and blood cultures are more often used in disseminated infections or extrap