Sections View Full Chapter Figures Tables Videos Full Chapter Figures Tables Videos Supplementary Content ++ DEFINITION ++ Waldenström macroglobulinemia (WM) is a lymphoid neoplasm resulting from the accumulation, predominantly in the marrow, of a clonal population of lymphocytes, lymphoplasmacytic cells, and plasma cells, which secrete a monoclonal immunoglobulin (Ig) M. WM corresponds to lymphoplasmacytic lymphoma (LPL) as defined in the Revised European–American Lymphoma (REAL) and World Health Organization (WHO) classification systems. Most cases of LPL are WM. Less than 5% of cases are IgA-secreting, IgG-secreting, or nonsecreting LPL. ++ EPIDEMIOLOGY ++ The age-adjusted incidence rate of WM in the United States is 3.4 per 1 million among males and 1.7 per 1 million among females. The incidence rate is higher among Americans of European descent. Americans of African descent represent approximately 5% of all patients. Approximately 20% of patients are of Eastern European descent, specifically of Ashkenazi-Jewish ethnic background. Approximately 20% of 257 sequential patients with WM presenting to a tertiary referral center had a first-degree relative with either WM or another B-cell disorder. ++ PATHOGENESIS ++ Cytogenetic Findings ++ Loss of all or part of chromosomes 17, 18, 19, 20, 21, 22, X, and Y is commonly observed, and gains in chromosomes 3, 4, and 12 also occur. Chromosome 6q deletions encompassing 6q21–25 have been observed in up to half of WM patients. ++ Somatic Mutations ++ MYD88L265P and CXCR4WHIM mutations are highly prevalent and trigger transcriptional factors that support the growth and survival of lymphoplasmacytic cells. ++ CLINICAL FEATURES ++ Presenting symptoms most commonly are fatigue, weakness, weight loss, episodic bleeding, and manifestations of the hyperviscosity syndrome. Physical findings include: — Lymphadenopathy — Hepatosplenomegaly — Dependent purpura and mucosal bleeding — Dilated tortuous retinal veins — Multiple flesh-colored papules on extensor surfaces (deposits of IgM reacting to epidermal basement membrane antigens) — Peripheral sensory neuropathy — Raynaud phenomenon, especially on exposure to cold — Splenomegaly and lymphadenopathy (uncommon) ++ Morbidity Mediated by the Effects of IgM ++ Table 69–1 lists the physiochemical and immunologic properties of the monoclonal IgM protein. ++Table Graphic Jump LocationTABLE 69–1PHYSICOCHEMICAL AND IMMUNOLOGIC PROPERTIES OF THE MONOCLONAL IGM PROTEIN IN WALDENSTRöM MACROGLOBULINEMIAView Table|Favorite Table|Download (.pdf) TABLE 69–1 PHYSICOCHEMICAL AND IMMUNOLOGIC PROPERTIES OF THE MONOCLONAL IGM PROTEIN IN WALDENSTRöM MACROGLOBULINEMIA Properties of IgM Monoclonal Protein Diagnostic Condition Clinical Manifestations Pentameric structure Hyperviscosity Headaches, blurred vision, epistaxis, retinal hemorrhages, leg cramps, impaired mentation, intracranial hemorrhage Precipitation on cooling Cryoglobulinemia (type I) Raynaud phenomenon, acrocyanosis, ulcers, purpura, cold urticaria Autoantibody activity to myelin-associated glycoprotein, ganglioside M1, sulfatide moieties on peripheral nerve sheaths Peripheral neuropathies Sensorimotor neuropathies, painful neuropathies, ataxic gait, bilateral foot drop Autoantibody activity to IgG Cryoglobulinemia (type II) Purpura, arthralgia, renal failure, sensorimotor neuropathies Autoantibody activity to red blood cell antigens Cold agglutinins Hemolytic anemia, Raynaud phenomenon, acrocyanosis, livedo reticularis Tissue deposition as ... GET ACCESS TO THIS RESOURCE Sign In Username Error: Please enter User Name Password Error: Please enter Password Forgot Username? Forgot Password? Sign in via OpenAthens Sign in via Shibboleth Get Free Access Through Your Institution Contact your institution's library to ask if they subscribe to McGraw-Hill Medical Products. What is MyAccess? Create a FREE MyAccess profile to: Use this site remotely Bookmark your favorite content Track your self-assessment progress and more!