myeloma and paraproteins Flashcards
what makes immunoglobulins (antibodies)
B cells - mostly plasma cells
1ry role of immunoglobulin
recognise and bind antigens
can directly impede biologic process or direct other components of immune system by tagging antigen
gross structure of immunoglobulin
2 heavy chains
2 light chains
Y shapes
immunoglobulin variable domains
fragment antigen binding (FAB)
immunoglobulin constant domains
Fc portion - defined by heavy chains defines role/subclass of antibody
immunoglobulin: types of heavy chains
IgG - gamma alpha - IgA, mucosal membrane immunity, found GIT Mu - IgM delta - IgD epsilon - IgE
immunoglobulin: light chain
kappa or lambda
random selection from each B cell what type it will make
each B cell only makes one type of light chain with one specificity
roughly half and half
paraprotein
monoclonal immunoglobulin present in blood or urine
if present it tells us there is monoclonal proliferation of a B lymphocyte/plasma cell somewhere in the body
serum protein electrophoresis
separates proteins based on size and charge
Ig run on gamma region of banding
can quantify bands on computer to see if there is abnormality in Ig composition
serum protein electrophoresis: what constitutes paraproteins
M spike
summary of tests: total Ig levels
measures Ig subclass by heavy chain/Fc
summary of tests: electrophoresis
assess antibody diversity
identify paraprotein
summary of tests: light chains
assess imbalance/excess of light chains in serum/urine
summary of tests: immunofuxation
identify what class of paraprotein is present
IgM paraproteins
lymphoma
maturing B-lymphocytes make IgM at start of immune response
IgG, IgA paraproteins
myeloma
mature plasma cells generate these types of Ig after isotype switching
myeloma
neoplastic disorder of plasma cells resulting in excessive production of single type Ig - paraprotein
clinical manifestation may occur from effects of plasma cells or paraprotein
myeloma features
bone disease
- lytic bone lesion
- pathological #
- spinal cord compression
- hypercalcaemia
bone marrow failure - anaemia
infections
myeloma: CRAB
hypercalcaemia
renal failure
anaemia
bone disease
myeloma: effects of paraprotein
renal failure
hyperviscosity
hypogammaglobinemia
amyloidosis
effects of paraprotein: renal failure
cast nephropathy
deposition Ig and blockage of tubules
effects of paraprotein: hyperviscosity
inc viscosity blood, impaired microcirculation and hypoperfusion
bleeding: retinal, oral, cutaneous
cardiac failure
pulmonary congestion
effects of paraprotein: hypogammaglobulinemia
impaired production of normal immunoglobulin
tendency to infection
effects of paraprotein: amyloidosis
AL amyloid
deposition of fibrillary protein
nephrotic syndrome
cardiac failure
autonomic neuropathy
cutaneous infiltration