Myeloma Flashcards
What are the 3 phases in the continuum to Myeloma?
- MGUS
- Smouldering myeloma (asymptomatic)
- Myeloma (symptomatic)
How are the 3 phases relating to Myeloma defined?
- MGUS
Presence of M protein 30g and/or plasma cells >10% but NO end-organ damage (CRAB) - Myeloma
M protein > 30g, plasma cells > 10% + end-stage organ damage (CRAB)
What are the features of MGUS?
Commonly found in the elderly, incidental findings
Precedes myeloma but those with MGUS have low risk of progression (1-2% annual risk)
No treatment required
Annual monitoring of M protein
What is CRAB?
C - calcium - hypercalcaemia
R - renal failure
A - anemia
B - bones - lytic bone lesions, bone pain and pathological fractures
What is the pathophysiology of how M protein causes symptoms/end-organ damage?
- Amyloidosis - infiltrates tissues - cardiac, GIT, nerves
- Syncope, sudden cardiac death, fatal arrhythmia
- Malabsorption
- Carpal tunnel, postural hypotension - Hyperviscosity - reduces blood flow
- headaches, MI/angina, stroke - Renal failure - deposition of complexes in renal tubules
How does myeloma result in hypercalcaemia and bone lesions?
Bone marrow infiltration by malignant plasma cells results in cytokine production, leading to:
- increased RANK/RANKL, increased osteoclast activity, increased bone resorption
- Increased Ca2+ and lytic bone lesions
What are the symptoms of hypercalcaemia
Bones, stones, groans and psychic overtones
- Bone pain
- Renal stones
- Abdominal pain, constipation, N+V, pancreatitis
- Confusion, depression, anxiety
+ Muscle weakness, hypertension, polyuria, polydipsia, weight loss, tiredness
How does myeloma result in anaemia?
What type?
Bone marrow infiltration decreases space and resources for production of RBCs
Normocytic anaemia*
Anaemia, neutropenia and/or thrombocytopenia
How does myeloma result in increased risk of infection?
Bone marrow infiltration/Increased clonal Ig, decreases production of normal Ig
+ Neutropenia from associated BM infiltration
