Tissue Type Test
How It Is Done
The health professional drawing blood
- Wrap an elastic band around your upper arm to
stop the flow of blood. This makes the veins below the band larger so it is
easier to put a needle into the vein.
- Clean the needle site with
- Put the needle into the vein. More than one needle stick
may be needed.
- Attach a tube to the needle to fill it with
- Remove the band from your arm when enough blood is
- Put a gauze pad or cotton ball over the needle site as
the needle is removed.
- Put pressure on the site and then put on a
How It Feels
The blood sample is taken from a vein in
your arm. An elastic band is wrapped around your upper arm. It may feel tight.
You may feel nothing at all from the needle, or you may feel a quick sting or
There is very little chance of a problem from
having a blood sample taken from a vein.
- You may get a small bruise at the site. You
can lower the chance of bruising by keeping pressure on the site for several
- In rare cases, the vein may become swollen after the
blood sample is taken. This problem is called phlebitis. A warm compress can be
used several times a day to treat this.
- Ongoing bleeding can be a
problem for people with bleeding disorders. Aspirin, warfarin (such as Coumadin), and
other blood-thinning medicines can make bleeding more likely. If you have
bleeding or clotting problems, or if you take blood-thinning medicine, tell
your doctor before your blood sample is taken.
A tissue type test is a blood test that
identifies substances called
antigens on the surface of body cells and tissues.
Checking the antigens can tell if donor tissue is safe (compatible) for
transplant to another person.
- For organ or tissue transplants, the results of
tissue type show whether the donated tissue matches. The antigen pattern match
is different for each type of transplant. For example, the match for a bone
marrow transplant needs to be closer than the match needed for a kidney
- To check family relationships, the more alike the
antigen patterns are, the more likely it is that the two people are
- If an antigen related to a disease is found, that disease is likely to be present.
What Affects the Test
Reasons you may not be able to
have the test or why the results may not be helpful include having had a blood
transfusion in the past 3 days.