PPD 2 step

The PPD 2 Step test provides a thorough tuberculosis (TB) screening by administering two separate PPD tests. This method is particularly useful for detecting latent TB infections, which may not be evident with a single test.

Here’s how it works:

First Step: A PPD injection is administered, which involves injecting a small amount of purified protein derivative (PPD) just under the skin.
Reading: After 48 to 72 hours, the test site is examined for a reaction.
Second Step: If the first test is negative or shows minimal reaction, a second PPD injection is administered, typically within one to three weeks of the first test.
Final Reading: The second test site is read after 48 to 72 hours to confirm or rule out TB exposure.
The PPD 2 Step test is often required for individuals in certain high-risk environments or those who may have had previous negative results from a single-step test. It helps ensure a more accurate assessment of TB exposure, aiding in early detection and effective management of TB risk.