Multiple myeloma
From IDWiki
Definition
- Monoclonal proliferation of plasma cell line causing disease
Classification
Monoclonal gammopathy of unknown significance (MGUS)
- M-protein present but <30 g/L, and
- Plasma cells <10% of bone marrow
- Absence of multiple myeloma end-organ damage
- If IgM, must also have no symptoms of a proliferative disorder or hyperviscosity
- Must think about Waldenstrom macroglobulinemia
Smoldering myeloma
- IgG or IgA M-protein >30 g/L or urinary M-protein (Bence-Jones) >500 mg/24h or plasma cells 10-60%
- Absence of multiple myeloma end-organ damage
Multiple myeloma
- SLiM CRAB symptoms
- Sixty percent plasma cells in marrow
- Light chain ratio (κ:λ or λ:κ) >100
- MRI showing at least two focal lesions
- Hypercalcemia >2.75 mmol/L
- Renal failure with creatinine >177 µmol/L or CrCl <40 mL/min
- Anemia with hemoglobin <100 g/L
- Bony lytic lesions
Clinical Manifestations
Complications
- Acute kidney injury
- Light chain deposition
- Hypercalcemia
- Urate crystals
- Amyloid deposition
- Myeloma infiltration
Diagnosis
- Routine bloodwork
- CBC with peripheral blood film, for anemia
- Calcium and creatinine
- SPEP with immunofixation
- Quantitative immunoglobulins
- Urinalysis
- UPEP with immunofixation
- Bone marrow biopsy
- Imaging
- Bone survey including spine, pelvis, skull, humeri, and femurs
- Add low-dose whole-body CT or MRI for smoldering myeloma and solitary plasmacytoma
Management
Antimicrobial Prophylaxis
- Levofloxacin 500 mg p.o. daily for the first 12 weeks after starting chemotherapy may reduce mortality1
References
- ^ Mark T Drayson, Stella Bowcock, Tim Planche, Gulnaz Iqbal, Guy Pratt, Kwee Yong, Jill Wood, Kerry Raynes, Helen Higgins, Bryony Dawkins, David Meads, Claire T Hulme, Irene Monahan, Kamaraj Karunanithi, Helen Dignum, Edward Belsham, Jeff Neilson, Beth Harrison, Anand Lokare, Gavin Campbell, Michael Hamblin, Peter Hawkey, Anna C Whittaker, Eric Low, Janet A Dunn. Levofloxacin prophylaxis in patients with newly diagnosed myeloma (TEAMM): a multicentre, double-blind, placebo-controlled, randomised, phase 3 trial. The Lancet Oncology. 2019;20(12):1760-1772. doi:10.1016/s1470-2045(19)30506-6.
