1. MLAB 1315- Hematology Keri Brophy-Martinez
Unit 24: MULTIPLE MYELOMA AND RELATED PLASMA CELL DISORDERS

2. Multiple myeloma
This is a disorder in which there is overproduction of abnormal plasma cells which are the final stage in the development of B lymphocytes.

3. Multiple myeloma Etiology 5 cases per 100,000 persons per year
50% greater risk for men than women
Risk increases with age; rare under 40
Suspected cause is chronic stimulation of the immune system from environmental sources.

4. Multiple myeloma Characteristics
Expanding plasma cell mass in bone marrow causes pancytopenia and destruction of the bone cortex. This is painful because nerves get stretched.
Increased production of immunoglobulin heavy and light chains (monoclonal gammopathy)
Heavy chains: IgG, IgA, IgD, IgE, IgM
Light chains: kappa, lambda
Most common type of multiple myeloma is increased production of IgG.
Hyperviscosity syndrome
Excess immunoglobulin causes viscous blood which sludges and causes fluid congestion.
Bence-Jones protein
Light chains spill into the urine and can be detected by lab test.
Causes kidney damage

5. Multiple myeloma Laboratory tests
Protein electrophoresis - separates the proteins in the serum
Immunoelectrophoresis - identifies the heavy and light chains
Quantitative immunoglobulins - quantitative measurement of the immunoglobulin chains
CBC and peripheral smear
Red cells form characteristic rouleaux formation (resemble stacked coins)
Plasma cells may be seen in advanced cases
The presence of significant numbers of plasma cells on peripheral blood smear constitutes plasma cell leukemia

6. Multiple myeloma: Lab tests con’t
ESR
Increased - serum protein causes red cells to stick together and fall faster
Bone marrow
Increased number of plasma cells which form “sheets”
Chemistry studies
Increased BUN and creatinine (kidney tests)
Increased calcium
Increased LDH

7. Multiple myeloma Treatment Chemotherapy Radiation for localized areas
Bone marrow transplant for younger patients

8. Waldenström’s macroglobulinemia
Overproduction of monoclonal IgM

9. Waldenström’s macroglobulinemia
Clinical features
Usually presents when patients are in their 70's.
Hyperviscosity syndrome is common.
Blurred vision
IgM interferes with platelet function and bleeding problems occur. Characteristic bruising is called cryoglobulinemic purpura
Cryoglobulins precipitate on exposure to cold

10. Waldenström’s macroglobulinemia
Therapy
Chemotherapy
Plasmapheresis