Mount Carmel Health System

Because of You

Print    Email
Decrease (-) Restore Default Increase (+)

Health Information

 

Quantitative nephelometry

Definition

Quantitative nephelometry is a test to quickly and accurately measure the specific level of certain proteins called immunoglobulins in your blood. Immunoglobulins are antibodies that help your body fight infection.

This test specifically looks for the proteins IgM, IgG, and IgA.

Alternative Names

Quantitative immunoglobulins

How the test is performed

A blood sample is needed. For information on how this is done, see: Venipuncture

How to prepare for the test

You may be asked not to eat or drink anything for 4 hours before the test.

How the test will feel

When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.

Why the test is performed

The test provides a rapid and accurate measurement of the amounts of the immunoglobulins M, G, and A.

Normal Values

  • IgG: 560 to 1800 mg/dL
  • IgM: 45 to 250 mg/dL
  • IgA: 100 to 400 mg/dL

Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.

The examples above show the common measurements for results for these tests. Some laboratories use different measurements or may test different specimens.

What abnormal results mean

Increased levels 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:

  • Agammaglobulinemia (very rare)
  • Leukemia
  • Myeloma

Increased levels of IgA may be due to:

  • Chronic infections, especially involving the gastrointestinal tract
  • Inflammatory bowel disease
  • Myeloma

Decreased levels of IgA may be due to:

  • Agammaglobulinemia (very rare)
  • Hereditary IgA deficiency
  • Myeloma
  • Protein-losing gastroenteropathy

It is important to note that other testing is required to confirm or make a diagnosis of any of the conditions above. Often, slight abnormalities in the levels of immunoglobulins are clinically insignificant.

What the risks are

There is very little risk involved with having your blood taken. Veins and arteries vary in size from one patient 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:

  • Excessive bleeding
  • Fainting or feeling lightheaded
  • Hematoma (blood accumulating under the skin)
  • Infection (a slight risk any time the skin is broken)

Special considerations

Nephelometry determines the total amount of each immunoglobulin but cannot distinguish specific antibodies. Other tests such as immunoelectrophoresis or immunofixation can be used to make these distinctions.

References

Ashihara Y, Kasahara Y, Nakamura RM. Immunoassays and immunochemistry. In McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 22nd ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 44.

McPherson RA, Massey HD. Laboratory evaluation ofimmunoglobulin function and humoral immunity. In McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 22nd ed. Philadelphia,Pa: Saunders Elsevier; 2011:chap 46.

Perry MC. Plasma cell disorders. In Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap193.


Review Date: 6/5/2012
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
adam.com
 
©  2014  

Mount Carmel Health System  |  Columbus, Ohio

Facebook Twitter YouTube CB