Plasma Cell Disorders Flashcards
Plasma Cells
Fully differentiated B cells that make Immunoglobulin.
Structure of Immunoglobulins.
2 heavy chains and 2 light chains.
Types of light chains.
Kappa and lambda.
Types of heavy chains.
G, A, M, E, D.
Rules of making an Ig.
An Ig can only be made of one type of heavy chain and one type of light chain.
Classification of Plasma Cell Disorders (WHO Classification).
(1) Monocloncal Gammopathy of Undetermined Significance (MGUS).
(2) Plasma Cell myeloma.
(3) Plasmacytoma.
Connects the two heavy chains to one another and the two light chains to one another.
Disulfide bonds.
IgM
Detected first in the body after a primary antigenic stimulus.
It’s a macroglobulin, so it’s too big to cross the placenta.
IgD
Very little in the serum.
IgA
Found in external secretions (bowel).
IgE
The one that you get when you have allergic reactions - has immediate hypersensitivity.
IgG
The main Ig in the blood. Detected after a second exposure to an antigen.
It crosses the placenta.
How to identify plasma cells in a histo section?
Clock-faced chromatin.
“M” Protein
A “monoclonal” serum protein made by neoplastic plasma cells or B lymphocytes.
Definition of clonal.
Derived from one cell of origin.
Monoclonal gammopathy
A neoplastic plasma cell produces plasma cells that are all neoplastic and have the exact same type of light and heavy chains.
What do monoclonal gammopathies produce and secrete into the blood?
M protein.
How do monoclonal plasma cells stain?
All the cells would stain one color. If there’s a mixture of colors, then it’s a polyclonal population.
SPEP
Serum Protein Electrophoresis
Test for a monoclonal serum protein.
Serum protein electrophoresis.
The 5 regions of a normal serum protein electrophoresis.
Albumin (highest), alpha1, alpha2, beta, and gamma.
What an abnormal SPEP looks like.
Goal Posts spike.
Major protein in the blood.
Albumin.
Done whenever you’re trying to figure out if there’s an abnormal protein in the blood.
SPEP.
Identifies monoclonal proteins in the serum or urine.
Immunofixation Electrophoresis.
Proteins are separated in the urine or serum and them incubated with specific antisera against Ig’s of interest.
Immunofixation Electrophoresis
Is Monoclonal Gammopathy of Undetermined Significance considered neoplastic?
No
Risk of progression of MGUS.
1.6%/year
Age population of MGUS
Elderly.
Plasmacytoma
A discrete, solitary mass of neoplastic monoclonal plasma cells in either bone or soft tissue.
Myeloma
An osteolytic cancerous tumor in the bone marrow.
Plasmacytomas have a normal….
bone marrow biopsy.
Symptoms of plasmocytomas.
Swelling/bone pain.
Myeloma presents as…
osteolytic bone lesions and abnormal marrow.
Plasma cell myeloma is AKA
Multiple myeloma.
Cells with eccentric nuclei are?
Plasma cells.
CRAB
Signs of organ or tissue impairment with multiple myeloma: Hypercalcemia, Renal failure, Anemia, Bone lesions.
Asymptomatic plasma cell myeloma.
Has no signs of CRAB.
What is kidney damage caused by in plasma cell myeloma?
Excessive Ig.
Where is plasma cell myeloma often found?
Vertebra, skull, scapula, ribs.
What does a gross specimen of multiple myeloma look like?
Punched out osteolytic lesions, and juicy, red color.
What don’t you see in normal plasma cells?
Nucleoli
Seen in normal plasma cells and myeloma cells.
Russell bodies, which are Ig inclusions.
Red blood cells and multiple myeloma.
The RBC’s in multiple myeloma are stacked, and this is called Rouleaux.
What is Rouleaux caused by?
Increased serum protein.
When a smear has Rouleaux, what disease could it be?
Plasma cell myeloma.
Bence Jones proteins
Monoclonal light chains in the urine.
Cause damage to the kidney as a result of multiple myeloma.
1) Monoclonal light chains form tubular casts.
2) Plasma cell infiltration.
3) Hypercalcemia makes calcium deposits.
4) Amyloid deposition.
Il-6
Promotes myeloma proliferation.
Role of bisphosphonates
Inhibit bone resorption/lysis by getting rid of osteoclasts.
