Medicine & USMLE

Waldenstrom Macroglobulinemia

Plasma Cell Dyscrasias
  1. Waldenstrom Macroglobulinemia
  2. Multiple Myeloma


Coming soon...

Key Points

  • Waldenstrom Macroglobulinemia
    • Cause
      • Plasma cell cancer that overproduces IgM
        • Named “macroglobulinemia” because IgM is the largest Ig (pentameric)
    • Presentation
      • No bone lesions or hypercalcemia
        • Excludes multiple myeloma
      • Peripheral neuropathy
      • Hyperviscosity syndrome
        • Headache
        • Blurry vision
        • Raynaud phenomenon
        • Retinal hemorrhages
      • Can lead to thrombosis (e.g. stroke)
      • Anemia
        • Excess plasma cell growth in bone marrow can crowd out normal hematopoiesis
        • Less common than in multiple myeloma
    • Diagnosis
      • M-spike in serum
        • Detected via serum protein electrophoresis (SPEP)
        • Represents overproduction of monoclonal Ig fragment
      • Bence-Jones protein in urine
        • Ig light chain accumulation is known as Bence-Jones protein
        • Detected via 24-hour urine collection and protein electrophoresis
        • Note: rapid urine dipstick is negative (only detects albumin)
      • >10% plasma cells on bone marrow biopsy
        • with IgM-containing vacuoles (lymphoplasmacytic lymphoma)
    • Treatment
      • Still area of active research
      • Rituximab
      • Bortezomib (protease inhibitor) may have utility
      • Plasmapheresis if hyperviscosity syndrome is present