DR Medhat MRCP

Paraproteinemia
= monoclonal gammopathies
= plasma cell dyscrasias
- It`s the presence of excessive amounts of a single monoclonal gammaglobulin (in this
case denominated "paraprotein") in the blood.
- It is usually due to an underlying immunoproliferative disorder[i.e neoplasms of 1ry
immune cells (B-cells,plasma cells,T-cells & NKC with excess production of Igs].
• Types :
- Paraproteinemias may be categorized according to the type of monoclonal protein
found in blood:
Light chains only (or Bence Jones protein). This may be associated with multiple
myeloma or AL amyloidosis.
Heavy chains only (also known as "heavy chain disease")
Whole immunoglobulins. In this case, the paraprotein goes under the name of
"M-protein" ("M" for monoclonal).
- Most heavy chains & whole Ig remain in the blood vessels while light chains
frequently escape & are excreted in urine (Bence Jones proteins)
- Paraproteins may aggregate together in the blood to form macroglobulinemia which
may lead to further complications e.g :
Certain macroglobulins tend to precipitate within blood vessel with cold, a
phenomenon known as cryoglobulinemia.
Others may make blood too viscous to flow smoothly (usually with IgM
macroglobulins), a phenomenon known as Waldenström macroglobulinemia.
• Causes (differential diagnosis) of a serum paraprotein :
Malignant :
1. MM
2. Lymphomas (usually B-cell NH- lymphoma with plasma cell component)
3. Leukaemias : CLL , plasma cell leukemia.
4. 1ry amyloidosis.
Benign /stable :
1. Monoclonal gammopathy of uncertain significance.
2. Cold haemagglutinin disease.
3. HIV .
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