Quantitative nephelometry is a lab test to quickly and accurately measure levels of certain proteins called immunoglobulins in the blood. Immunoglobulins are antibodies that help fight infection.
This test specifically measures the immunoglobulins IgM, IgG, and IgA.
A blood sample is needed.
You may be asked not to eat or drink anything for 4 hours before the test.
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or slight bruising. This soon goes away.
The test provides a rapid and accurate measurement of the amounts of the immunoglobulins IgM, IgG, and IgA.
Normal results for the three immunoglobulins are:
The examples above show the common measurements for these test results. Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results. Some labs use different measurements or test different samples.
An increased level of IgG may be due to:
Decreased levels of IgG may be due to:
Increased levels of IgM may be due to:
Decreased levels of IgM may be due to:
Increased levels of IgA may be due to:
Decreased levels of IgA may be due to:
Other tests are needed to confirm or diagnose any of the conditions above.
There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight, but may include:
Reviewed By: Richard LoCicero, MD, private practice specializing in hematology and medical oncology, Longstreet Cancer Center, Gainesville, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.