IgA myeloma complicated by fractures of the bones and hyperviscosity syndrome--report of an autopsied case.

: A case of IgA (kappa type) myeloma complicated by fractures of the bones and hyperviscosity syndrome is presented. A 56-year-old woman who had been followed as an outpatient with diabetes mellitus for about 16 years, developed multiple myeloma. She also showed symptoms and signs of hyperviscosity syndrome; hemorrhagic diathesis, blurred vision and episodes of transient ischemic attacks of the brain, and fractures of the bones by small powers of trauma. At autopsy, almost all bones showed infiltration of multiple myeloma of IgA-kappa type and severe osteoporosis accompanied with proliferation of osteoclasts. The association of IgA myeloma with hyperviscosity syndrome and/or bone destruction was discussed. The "serum hyperviscosity syndrome" has been described clinically as the triad of bleeding, visual signs and symptoms, and neurologic manifestations. And this syndrome has been associated frequently with macroglobulinemia of Waldenstrom, occasionally with immunoglobulin (Ig) G myeloma, rarely with IgA myeloma, and with other dysproteinemia. Myeloma is also characterized by extensive bone destruction and is accompanied by susceptibility to fracture, although Waldenstrom's macroglobulinemia, acute leukemia or chronic leukemia are rarely associated with bone resorption. The present report describes a patient with IgA myeloma complicated by hyperviscosity syndrome and multiple bone fractures.