Monoclonal gammopathy of undetermined significance (MGUS) is a chronic disease that results in the appearance of abnormal proteins in the blood.1 These proteins are formed from white blood cells. These proteins are produced by plasma cells in the bone marrow. The presence of M proteins does not have a significant impact on health in its certain level. The disease does not show signs and symptoms. It is detected accidentally in the blood tests done for other diseases. It has slow progress to cancer in few cases.


How is MGUS or Monoclonal Gammopathy Of Undetermined Significance Diagnosed?

Monoclonal gammopathy of undetermined significance does not show signs or symptoms in most of the cases. it is diagnosed accidentally when blood tests are done for some other reasons. These blood tests reveal the presence of M proteins. It is necessary to check the levels of M proteins in the blood to keep a close observation on the progress of the disease. Doctors recommend a set of tests that can find M protein and its levels. These tests can reveal out the causes of the presence of M proteins and the extent of its effects on the body. Following are the tests are done for this purpose-

Other Blood Tests- complete blood tests are done to find out the count of other blood cells in the patient’s blood. This will help to know the kidney function through serum creatinine test and the levels of calcium in the blood through serum calcium test. This can reveal other conditions like multiple myeloma.


Urine Tests- the abnormal presence of M protein in the blood may lead to slow damage to the kidney.2 To determine the kidney damage, urine tests are performed to detect any trace of M proteins in the urine filtered by kidneys.

Imaging Tests- imaging tests like X-ray, MRI scan or CT-positron emission tomography helps to determine the condition of the bones abnormalities caused by Monoclonal gammopathy of undetermined significance. This will detect the bone fractures.


Bone Marrow Tests- these tests are done as the M proteins are formed in the bone marrow. A hollow needle is inserted into the bone marrow and a portion of the bone marrow is extracted. It is usually done from hip bones. It helps to analyze the number of plasma cells produced in the bone marrow. These tests are recommended when the patient is at high risk of developing serious complications of Monoclonal gammopathy of undetermined significance or the patient is having bone lesions, high calcium levels, kidney failure or unexplained anemia.

Monoclonal gammopathy of undetermined significance (MGUS) is a disease that is characterized by the appearance of abnormal proteins namely M proteins or monoclonal proteins in the blood. When the body is all set to fight against diseases, it initiates the production of antibodies in the body. In MGUS, M proteins are produced instead of antibodies. They are produced by plasma cells in bone marrow instead of antibodies. These proteins circulate in the blood. These proteins circulate in the blood. This disease is a slow developing disease that may take years to progress into serious complications like myeloma, lymphoma, etc.

The risk factors that can promote the development of MGUS are-

Its incidence increases with increasing age. It develops in old people whose age is 70 years or above. Its incidence is found to be highest in the age of 85 years or above.

  • Constant exposure to pesticides also possesses the risk of developing MGUS.
  • The disease is more common in Africans, and African -Americans than white people.
  • Males are more affected than females.
  • There are high chances of developing monoclonal gammopathy of undetermined significance if there is a family history of this disease.


Monoclonal gammopathy of undetermined significance is marked by the presence of an abnormal presence of monoclonal proteins in the blood. It is diagnosed by blood tests accidentally. Few tests such as complete blood test, urine tests, imaging tests, and bone marrow tests are recommended to know the extent of the disease.


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Pramod Kerkar

Written, Edited or Reviewed By:


Pain Assist Inc.

Last Modified On: August 20, 2019

This article does not provide medical advice. See disclaimer


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