Plasmacytoid lymphocytic lymphoma presenting with IgG hyperviscosity syndrome and peritoneal lymphomatosis

We reported a 74-year-old woman with plasmacytoid lymphocytic lymphoma who initially presented with exertional dyspnea, conscious disturbance, ascites, and lytic skull lesions. Protein electrophoresis and immunoelectrophoresis showed monoclonal IgG-lambda gammopathy with IgG level of 13300 mg/dl and marked suppression of the residual normal immunoglobulins. Abdominal computed tomography (CT) revealed a pattern mimicked cancerous peritonitis. She responded to plasmapheresis with much clinical improvement of the hyperviscosity syndrome but died of H. influenza sepsis 3 weeks after diagnosis. The unusual and interesting features of this case included: (1) IgG hyperviscosity syndrome and diffuse peritoneal involvement as the initial manifestations in plasmacytoid lymphocytic lymphoma, and (2) presence of lytic bone lesions in conjunction with high level of M--component and marked suppression of normal residual immunoglobulins in a patient with lymphoma rather than multiple myeloma.