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Monoclonal Gammopathy of Undetermined Significance (MGUS)

What is monoclonal gammopathy of undetermined significance?

Monoclonal gammopathy of undetermined significance (MGUS) is a typically innocuous condition determined by the presence of an unusual protein in the blood. The protein, referred to as monoclonal or M protein, is produced by plasma cells in bone marrow. MGUS rarely causes complications but has been observed in some cases to progress to some forms of blood cancer.

What are the symptoms of monoclonal gammopathy of undetermined significance?

Most people with MGUS do not experience symptoms. In some cases, rash or irritation may be present. In others, there has been observed issue relating to the nerves such as tingling or numbness.

What causes monoclonal gammopathy of undetermined significance?

MGUS occurs when plasma cells produce the abnormal M protein. The exact causes or abnormalities leading to the production of the M protein are unknown. Genetic changes, and environmental factors are both currently suspected. The average age at which an MGUS diagnosis is determined is age 70. Africans and African-Americans seem to be at greater risk, as do men. A family history of MGUS also seems to increase risk of developing MGUS.

How is monoclonal gammopathy of undetermined significance diagnosed?

MGUS is most typically diagnosed during blood tests for other disorders or conditions. The blood tests may show abnormal proteins or unusual amounts of normal proteins. Under these circumstances, your doctor may order further tests. Further blood tests, urine tests, MRI or PET scan, and/or bone marrow tests may be ordered to rule out other causes.

What are the treatments for monoclonal gammopathy of undetermined significance?

MGUS does not require treatment. Regular checkups should be performed to monitor general health starting at roughly six months after an MGUS diagnosis. This helps aid early detection should MGUS progress to other disease states. 

Where can I find out more about monoclonal gammopathy of undetermined significance?

Monoclonal Gammopathy of Undetermined Significance (MGUS) Articles