Plasma Cell Dyscrasias Flashcards
plasma cell dyscrasias - overview
*genetic mutation results in increased numbers of plasma cells with increased amounts of antibody production
*excess antibodies can cause end organ dysfunction
*results in a continuum of disorders, depending on amount of excess protein present
continuum of plasma cell dyscrasias
MGUS (monoclonal gammopathy of undetermined significance) < multiple myeloma < plasma cell leukemia
note - these are ranked in order of increasing numbers of plasma cells and protein production
plasma cell dyscrasias - diagnosis
*bone marrow biopsy & aspirate - to measure the number of plasma cells (determines MGUS [<10%] vs. multiple myeloma [>10%])
*to measure the amount of protein/antibody being produced:
-CMP (total protein elevated in excess of albumin)
-serum quantitative immunoglobulins
-serum protein electrophoresis
-serum immunofixation
-serum free light chains
serum quantitative immunoglobulins [a diagnostic test of plasma cell dyscrasias]
*tells us how much immunoglobulin a patient has
*example: provides IgG, IgA, and IgM, with reference ranges
SPEP (serum protein electrophoresis) test - normal curve
*measures the types of proteins in a blood sample’s serum:
1. albumin peak (should be the highest)
2. alpha-1 peak (alpha-1 antitrypsin, etc)
3. alpha-2 peak (haptoglobin, etc)
4. beta peak (transferrin, some immunoglobulins)
5. gamma peak (MOST IMMUNOGLOBULINS, not just IgG)
what peak do we look at in an SPEP to determine immunoglobulin levels
gamma peak (far right)
SPEP for a monoclonal gammopathy (plasma cell dyscrasias)
*clonal disorder
*one narrow gamma peak
*all the proteins are the SAME so they travel the same distance on the electrophoresis gel (result is a tall, narrow peak
*quantitates the M spike (M is for monoclonal)
IEP (immuno electrophoresis) for a monoclonal gammopathy (plasma cell dyscrasias)
*run patient’s serum on gel
*stain for different antibodies using specific reagents
*confirms clonality
*tells us which antibody is in excess (IgG, IgA, IgM, kappa or lambda)
serum free light chains test for plasma cell dyscrasias
*get quantification of light chains in the serum
-free kappa, serum (3.3-19.4)
-free lambda, serum (5.71-36.3)
-free kappa/lambda ratio (0.26-1.65)
end organ damage of the BONES from plasma cell dyscrasias
*increased osteoclast activation (breaks down bones)
*leads to lytic lesions in the bones:
-calvarium, spine, ribs, pelvis, long bones
end organ damage of the KIDNEYS from plasma cell dyscrasias
multiple reasons:
1. deposition of immunoglobulins
2. cast nephropathy or “myeloma kidney”
3. infiltration of kidney by plasma cells
end organ damage of the BONE MARROW from plasma cell dyscrasias
*increased numbers of plasma cells in the marrow, taking up space
*normochromic, normocytic anemia
*circulating plasma cells usually only seen with plasma cell leukemia
*classic changes (ROULEAUX - stacks of coins) seen on peripheral smear
end organ damage of the ELECTROLYTES from plasma cell dyscrasias
*hypercalcemia (due to osteoclast activation) contributes to renal dysfunction
*symptoms of plasma cell dyscrasias: “stones, bones, groans, and moans”:
-stones = kidney stones
-bones = increased bone resorption
-groans = constipation
-moans = psych issues
plasma cell dyscrasias - treatment
*depends on where the patient falls along the continuum
*observation - MGUS
*oral chemotherapy - multiple myeloma
*intensive IV chemotherapy - plasma cell leukemia
Waldenstrom’s Macroglobulinemia
*IgM plasma cell dyscrasia (along the entire continuum)
*up to 30% of patients will have HYPERVISCOSITY SYNDROME:
-headache, vision changes, dizziness, tinnitus, ataxia, etc
-this is a medical emergency!
-treatment = plasmapheresis prior to chemotherapy
note - hyperviscosity is due to too many large immunoglobulins (because IgM exists in pentamers, larger than the other Ig classes)
