Monoclonal gammopathy of undetermined significance

Last reviewed: 24 Feb 2023
Last updated: 28 Mar 2019



History and exam

Key diagnostic factors

  • at-risk demographic (male, age >50 years, African ancestry)
  • clinically asymptomatic
  • positive family history
  • history of radiation exposure
  • history of pesticide exposure
More key diagnostic factors

Other diagnostic factors

  • history of immunosuppression or infections
  • presence of peripheral neuropathy
Other diagnostic factors

Risk factors

  • male sex
  • age >50 years
  • African ancestry
  • family history of MGUS or multiple myeloma
  • immune-mediated conditions
  • radiation exposure
  • pesticide exposure
More risk factors

Diagnostic investigations

1st investigations to order

  • electrophoresis with immunofixation and measurement of serum immunoglobulins
  • FBC with differential
  • serum calcium
  • serum creatinine
  • urinalysis and 24-hour urine collection with electrophoresis and immunofixation
  • serum free light chains assay
  • metastatic bone survey (conventional x-ray or whole body low-dose CT scan)
More 1st investigations to order

Investigations to consider

  • bone marrow aspiration and/or biopsy
  • bone mineral density scan
  • MRI scan
  • PET scan
More investigations to consider

Treatment algorithm


confirmed MGUS



Shaji Kumar, MD

Professor of Medicine

Division of Hematology

Mayo Clinic




SK has served as a consultant for Janssen, Abbvie, Amgen, Merck, Celgene, Takeda, and Skyline.


Professor Shaji Kumar would like to gratefully acknowledge Dr Ola Landgren, a previous contributor to this topic. OL is an author of several references cited in this topic.

Peer reviewers

Daniel Catovsky, MD

Consultant Haemato-Oncologist

Section of Haemato-Oncology

Brookes Lawley Institute of Cancer




DC declares that he has no competing interests.

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