Myeloma and Plasma Cell Dyscrasias Flashcards
What are immunoglobulins composed of?
2 heavy chains and 2 light chains
Which immunoglobulins ae monomers?
IgD
IgE
IgG
Which immunoglobulins are dimers?
IgA
Which immunoglobulins are pentamers?
IgM
Where are B cells produced?
bone marrow
What becomes the antigen binding site on the immunoglobulin?
Random selection of V D and J genes
Where do B cells travel to get antigens?
Follicle germinal centre of the lymph node
What is found in the pale perinuclear area of a plasma cell?
Golgi apparatus
Describe the nucleus of a plasma cell
Clock-face
Which scenarios would cause a polyclonal increase in immunoglobulins?
Infection
Autoimmunity
Malignancy
Liver disease
Give examples of causes of paraproteinaemia?
MGUS Amyloidosis Myeloma Lymphoma CLL
How are immunoglobulins detected in the blood?
Electrophoresis
Immunofixation
What is a Bence-Jones protein?
Kappa free immunoglobulin light chain
Where are Bence-Jones proteins found in myeloma?
Urine
Outline the pathogenesis in multiple myeloma
Uncontrolled overproduction of one immunoglobulin which pushes out other healthy cells from the bone marrow
What is a paraprotein?
Abnormal immunoglobulin light chain produced by abnormal immunoglobulin
Why are lytic lesions found in myeloma?
Abnormal immunoglobulins activate osteoclasts through IL-6
What is the most common myeloma?
IgG
What is the second most common myeloma?
IgA
How does myeloma present?
HyperCalcaemia Renal failure Anaemia Bone pain (CRAB)
How does the myeloma-induced renal failure present?
N%V
Pruritus and muscle cramps
Dyspnoea and oedema
What causes nausea and vomiting in renal failure?
Uraemia
What causes pruritus and muscle cramps in renal failure?
Increased phosphate
What causes dyspnoea and oedema in renal failure?
Fluid retention
Describe the anaemia in myeloma?
Normocytic normochromic
Describe the bone pain in myeloma
Worse on activity
Common in spine and ribs
What causes confusion, weakness and fatigue in myeloma?
Hypercalcaemia
What causes headache and visual disturbance in myeloma?
Hyper viscosity
What causes peripheral neuropathy in myeloma?
Amyloid deposition
What do U&Es show in myeloma?
Raised CK
Hypercalcaemia
What does blood film show in myeloma?
Rouleaux
How is myeloma status assessed?
Bone marrow biopsy
Immunohistochemistry
Cytogenetics
Skeletal survey (MRI)
What is the criteria for symptomatic myeloma?
Clonal plasma cells >10% of biopsy
Paraprotein in serum or urine
End-organ damage
What is the criteria for asymptomatic myeloma?
Clonal plasma cells >10% biopsy
Serum paraprotein >30g/L
No myeloma related end organ damage
How is asymptomatic myeloma treated?
Watchful waiting
What is the MGUS criteria?
Serum paraprotein <30g/l
Clonal plasma cells <10% on bone marrow biopsy
No myeloma end organ damage
How is myeloma treated?
<65 - combination chemo and autologous stem cell transplant
>65 - combination chemo
What is “maintenance treatment” for myeloma?
Low dose chemo on a regular basis
What symptomatic relief is given in myeloma?
Analgesia - not NSAID
Local radio - for cord comp
Bisphosphonates - bone pain
Vertebroplasty - stabilise vertebra
What drugs are used with chemo in myeloma treatment?
Corticosteroids, dexmet, prednisolone
Alkylating agents
Thalidomide
Lenalidomide
Give examples on an alkylating agent
Cylcophosphamide
Melphalan
What is AL amyloidosis?
Mutation in the light chain of antibodies so they can’t be broken down
Accumulate in tissue as insoluble beta pleated sheet
How is AL amyloidosis treated?
Chemo to switch off light chain supply
What does biopsy and stain show in AL amyloidosis?
Congo red stain
Apple-green birefringence under polarised light
Which investigations can be used to show amyloid deposition in other organs?
Serum amyloid scintigraphy scan
Echo
Nephrotic range proteinuria
Which immunoglobulin is involved in Waldenstrom’s macroglobulinaemia?
IgM
What is Waldenstrom’s Macroglobulinaemia?
Clonal disorder of cells resulting in a lymphoplasmacytoid neoplasm
Why does Waldenstrom’s Macroglobulinaemia cause a greater degree of hyperviscosity than myeloma?
IgM has more binding sites
How does hyperviscosity syndrome present?
Fatigue Visual problems Confusion/coma Bleeding Cardaic failure
How is Waldenstrom’s Macroglobulinaemia treated?
Plasmapheresis to physically remove IgM
Chemo