Incidence of WM is 3.4 per million in men and 1.7 per million in women. WM sometimes has familial clustering with multiple myeloma or other B-cell disorders. Median age of onset for WM is approximately 60.
Lymph nodes and the spleen are sometimes enlarged, and anemia is common. Plasma cells are increased in the bone marrow. The abnormal plasma cells usually have a clonal mutation: MYD88 L265P.
About one-quarter of patients have pain and peripheral sensorimotor neuropathy, with associated foot drop and ataxia, that is related to clonal antibodies to myelin-associated glycoproteins or other nerve sheath molecules.
High levels of monoclonal proteins increase plasma viscosity, leading to headaches, blurred vision (with sausaging of retinal vessels and retinal petechiae and hemorrhage), nose bleeds, leg cramps, impaired mentation, and intracranial hemorrhages.
Light-chain components can cause proteinuria and renal failure. Autoantibodies to red cells (often cold agglutinins) can cause anemia, and hyperviscosity can be associated with Raynaud phenomenon, acrocyanosis, and livedo reticularis.
Skin lesions include the following:
- Vasculitis and cryoglobulinemia with purpura
- Acrocyanosis and livedo reticularis
- Acquired cutis laxa
- Blistering of the skin – Due to an immune response elicited by IgM antibodies against different molecules binding in the basement membrane zone. IgM antibodies can be detected by direct and indirect immunofluorescence testing.
- Schnitzler syndrome has chronic urticarial eruptions, frequent fevers, arthralgias, and, frequently, increased neutrophils and sedimentation rates. Biopsy of the urticarial lesions shows a neutrophilic infiltrate that is different from most of the common forms of urticarial disease.
C88.0 – Waldenström macroglobulinemia
35562000 – Waldenstrom's macroglobulinemia
Vasculitis and cryoglobulinemia – Lesions often on extremities with purpura and often necrosis; may be angular with geographic or linear borders, suggesting factitial disease. Consider other forms of vasculitis, including drug reactions (eg, drug-induced leukocytoclastic vasculitis) and hepatitis B and C.
Autoantibody-induced blistering of the skin:
- Acquired epidermolysis bullosa
- Bullous lupus erythematosus
- Bullous pemphigoid
- Paraneoplastic pemphigus
- Papular mucinosis (see also lichen myxedematosus)
- Metastatic carcinoma
- Lymphoma leukemia infiltration