A tuberculosis skin test is carried out to know if your body has previously been exposed to tuberculosis (TB) virus. This test is done on your inner forearm skin. A person who experiences symptoms of TB has to undergo this test to confirm the presence of TB bacteria.
The Procedure
The procedure of the tuberculosis skin test is as follows:
- Your doctor or health care professional would ask you to sit down and extend your forearm.
- The skin on the inner forearm is then cleaned with an alcohol swab or an antiseptic and allowed to dry.
- Your doctor would then inject a small shot of purified protein derivative (PPD) into the upper layer of the skin.
- You might notice a slight swelling or a bump on your skin due to the injection of PPD which is normal.
- You can continue with your daily activities and the skin need not be covered with a bandage.
- Visit your doctor after two or three days to get the result of the test.
Does it pain?
Well, this is the most common question that people ask as they know about the procedure. The only
pain that you might experience is a pinch or a quick sting from the needle.
Are there any risks associated with this test?
- Most people who undergo this test do not experience any allergy or reaction.
- In rare cases, some people might develop a severe reaction after undergoing this test. People who have previously had TB are more at risk of an allergic reaction. This causes pain and swelling at the site.
- There is absolutely no chance of contracting TB by undergoing this test as live bacteria is not used.
What happens after the test?
- There will be some redness on the skin after the test but this does not necessarily mean that you have TB.
- Do not scratch the skin as it might lead to increased swelling and redness. This would make it tough to determine the result.
- If you experience itching, put a cold cloth on the skin and then let the skin dry. This would provide relief.
Consult your doctor if you notice:
- Swelling in your forearm
- Bumps in your armpit or presence of swollen lymph nodes
- Fever
Result
Redness on the forearm skin does not indicate the presence of TB bacteria. Redness along with a small bump means that you might have had TB at some point of time in your life. Your doctor would determine whether you have TB by measuring the size of the bump.
