Health
Fact-checked

At TheHealthBoard, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

What Is Quantitative Immunoglobulin?

Dan Harkins
Dan Harkins

Doctors measure the amount of immunity-imparting proteins in the human body with a blood test called quantitative nephelometry. Specifically, the exam detects the levels for three distinct immunoglobulins, or antibodies, commonly referred to by the letters IgA, IgG and IgM. When deficiencies or surpluses are noted for any of the three quantitative immunoglobulin levels, it could indicate any number of conditions or diseases.

A functioning immune system will naturally produce the amount of antibodies needed to combat most of the antigens encountered by the body throughout life, from bacterial infections and cancers to toxic substances and other foreign matter. Many conditions or diseases can counter this system, though, like Autoimmune Immunodeficiency Syndrome (AIDS), lupus, multiple sclerosis, chronic thyroid disease and even arthritis. These are some of the conditions that a quantitative immunoglobulin test seek to identify.

A blood test can be used to measure the amount of immunity-imparting proteins in the body.
A blood test can be used to measure the amount of immunity-imparting proteins in the body.

When a quantitative immunoglobuliin test reveals normal results, it means that all three antibodies are present at prescribed levels. That means IgA is between 100 and 400 mg/dL, IgG is 560 to 1,800 mg/dL and IgM is 45 to 250 mg/dL. This indicates that the body is likely to be deploying the correct matrix of antibodies to defend itself in a healthy way. When patients have levels above or below any of the three ranges, a key step has been taken in helping a clinician determine whether they have a disorder in need of treatment.

Immunoglobulins are proteins formed by white blood cells that act as antibodies.
Immunoglobulins are proteins formed by white blood cells that act as antibodies.

When IgA levels are too high or too low, it could result in digestive problems. An infection, irritable bowel syndrome, myeloma or any other disease in the digestive tract are potential suspects. The other two antibody measures, by contrast, mean different things depending on whether the level is too high or too low.

With IgG, low levels on a quantitative immunoglobulin exam could mean leukemia, myeloma and preeclampsia. Increases in IgG, though, could mean the onset of other serious conditions like an infection, liver disease or chronic arthritis. High and low levels of IgM, similarly, point toward different conditions: lymphona, arthritis or monomucleosis if high; leukemia, myeloma and other rarer conditions if low.

Rheumatoid arthritis is an autoimmune disorder that causes painful, inflamed joints.
Rheumatoid arthritis is an autoimmune disorder that causes painful, inflamed joints.

Since some conditions show up with decreases or increases in more than one antibody that is measured with the quantitative immunoglobulin test, doctors and lab technicians examine each level individually and as a group to make more certain diagnoses. In many cases, patients are administered the quantitative immunoglobulin test when suffering from a chronic infection. This may lead a physician to suspect the patient is suffering from some condition that is compromising the immune system.

Discuss this Article

Post your comments
Login:
Forgot password?
Register:
    • A blood test can be used to measure the amount of immunity-imparting proteins in the body.
      By: Wojciech Sobiech
      A blood test can be used to measure the amount of immunity-imparting proteins in the body.
    • Immunoglobulins are proteins formed by white blood cells that act as antibodies.
      By: fotoliaxrender
      Immunoglobulins are proteins formed by white blood cells that act as antibodies.
    • Rheumatoid arthritis is an autoimmune disorder that causes painful, inflamed joints.
      By: Lisa F. Young
      Rheumatoid arthritis is an autoimmune disorder that causes painful, inflamed joints.
    • IgA is found in tears.
      By: olly
      IgA is found in tears.
    • Low levels on a quantitative immunoglobulin exam could indicate preeclampsia.
      By: Valua Vitaly
      Low levels on a quantitative immunoglobulin exam could indicate preeclampsia.
    • Irritable bowel syndrome may occur as a result of high or low IgA levels.
      By: stefanolunardi
      Irritable bowel syndrome may occur as a result of high or low IgA levels.
    • Antibodies help destroy infectious organisms that invade the blood.
      By: Tyler Olson
      Antibodies help destroy infectious organisms that invade the blood.
    • Quantitative nephelometry detects the levels of the antibodies IgG, IgA and IgM.
      By: designua
      Quantitative nephelometry detects the levels of the antibodies IgG, IgA and IgM.