Sub-classes

• MGUS - Monoclonal Gammopathy of Undetermined Signficiance
• Smoldering MM

Presentation (SLiM CRAB)

• S - Sixty (60%+ bone marrow clonal plasma cell)

• L - Serum Free Light Chain : Involved / uninvolved FLC ratio ≥ 100, involved light chain should be >100mg/L

• M - MRI: 1 + focal bone lesion that is > 5 mm in size

• C - !Hypercalcemia - ↑Ca (> 2.5), PTH-independent ↑Ca

  • Ca Calcium (2.2-2.5)
  • Decreased Albumin (40), need to measure ionized Ca or adjust using the formula
  • excessive osteoclastic bone resorption due to local secretion of osteoclast-activating cytokines and factors by malignant plasma cells within the bone marrow microenvironment.

• R - !AKI - Acute Kidney Injury /CKD

  • Primary Amyloidosis → Nephritic syndrome
  • Myeloma Kidney (Cast Nephropathy) → ATN - Acute tubular necrosis

• A - Anemia (↓Hb)

• B - Secondary OP - Osteoporosis

  • Especially with Vertebral Fracture
  • Present with Bone pain or Back Pain

Investigation

• SPEP
• CBC
• XR (Radiography) to ID lytic lesion
• Bone Marrow Biopsy
• Serum Free Light Chain (involved vs. uninvolved ratio)