Canterbury DHB
The higher the paraprotein level, the less likely that the diagnosis will be MGUS. IgG levels above 21 g/L and IgA levels above 16 g/L correlate with bone marrow plasma cell burdens of greater than 10% and bone marrow biopsies are likely to be more useful above these levels. A Bone marrow biopsy is also indicated at lower levels of paraprotein if other findings suggest myeloma.
IgM paraprotein levels do not correlate with bone marrow disease burden and should not be used to guide the decision to perform a bone marrow biopsy.
Non-IgG MGUS paraproteins are deemed higher risk.
Other tests useful to exclude myeloma and to assess MGUS prognosis include
Topic Code: 39808