The test measures the amount of a protein called C3 that enhances the action ofantibodiesand other disease-fighting immune cells.
C3 is part of the complementary immune system.
The test can also assess whether a treatment for an autoimmune disorder is working.
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This article explains the purpose of a C3 complement test and why your healthcare provider may order one.
They may also rise if you are responding to autoimmune therapies.
What to Expect
The C3 complement test involves a simple blood draw.
No preparation is needed.
The test may be performed at a hospital, clinic, lab, or your healthcare provider’s office.
There is nothing that would prevent someone from having a C3 complement test.
Furthermore, there are very few risks associated with the procedure.
This test generally costs between $35 to $60.
Most health insurance plans will cover all or part of the cost when used for a medical purpose.
Keep in mind that if other blood tests are ordered, the out-of-pocket costs may be higher.
Wear either a short-sleeved top or a shirt with sleeves you could roll up.
Waiting times can vary depending on the facility.
The blood draw itself only takes a couple of minutes.
There are no food, drink, or medication restrictions involved with a C3 complement test.
The blood sample will be obtained by a nurse or a technician known as aphlebotomistspecially trained in blood draws.
Once seated, will be asked to choose the arm you want your blood drawn from.
If you do, let the nurse or phlebotomist know.
Otherwise, you are free to go and can drive yourself home.
There may be bruising and pain at the puncture site which usually resolve on their own without treatment.
Infections are extremely rare.
Interpreting the Results
The C3 complement test is measured in milligram per deciliter (mg/dL).
The results are based on areference range of values.
Anything above the reference range is considered high and anything below the reference range is considered low.
There are many different reasons why C3 protein values may be low or high.
If an abnormal result is returned, additional tests may be ordered.
If you receive an abnormally high or low value, don’t panic or jump to any conclusions.
Simply ask your healthcare provider what the results may mean and why other tests may be needed.
C3 is one of more than 30 different proteins that make up the complementary immune system.
