Myeloma and paraproteins Flashcards
Which region of an immunoglobulin defines its target binding?
Fab region
Which region of an immunoglobulin defines its subclass?
Fc region
What is a paraprotein?
Monoclonal immunoglobulin present in blood or urine
If present, it tells us that there is monoclonal proliferation of a B lymphocyte / plasma cell somewhere in the body
What does serum protein electrophoresis do?
Separates protein based on size and charge
Forms a characteristic pattern of bands of different widths and intensities based on proteins present
Assesses antibody diversity and identifies paraprotein
What is immunofixation used for?
Identifies what class of paraprotein is present
What do light chain tests do?
Assesses imbalance/excess of light chains in urine/serum
What kind of paraproteins cause lymphoma?
IgM
What kinds of paraproteins cause myeloma?
IgG
IgA
What is myeloma?
Neoplastic disorder of plasma cells resulting in excessive production of a single type of immunoglobulin (paraprotein)
How does myeloma affect the bones?
Lytic bone lesions Pathological fractures Cord compression Hypercalcaemia Bone marrow failure
What are some consequences of myeloma?
Hypercalcaemia
Renal failure
Anaemia
Bone disease
How do paraproteins cause renal failure?
Immunoglobulin deposition and blockage of renal tubules
Cast nephropathy
How do paraproteins affect the blood?
Anaemia
Hyperviscosity
Hypogammaglobulinaemia
Cardiac failure
How is myeloma diagnosed?
Finding excess plasma cells in bone marrow
What is the most common paraprotein cause of myeloma?
IgG
