Hyperviscosity in Non-IgM Lymphoplasmacytic Lymphoma

Abstract

HEMATOLOGY & ONCOLOGY dL) and 140 mg/dL (40-230 mg/dL) respectively. Serum protein electrophoresis showed a monoclonal protein band in the gamma region at 5.9 g/dL (0.5-1.6 g/dL), which was further classified as IgG kappa. Kappa/ lambda ratio was calculated at 3.7. His blood repeatedly clotted in the tube despite multiple attempts. Some tests were unable to be performed due to increased serum viscosity. He had inconsistent sodium levels ranging between 113-150 mEq/L without intervention. Hepatic function tests were normal, hepatitis B and C were negative, and cryoglobulin testing was negative. Peripheral flow cytometry showed no abnormal population of B or T cells. CT of the chest, abdomen, and pelvis showed bilateral axillary, subpectoral, mediastinal, upper abdominal, and retroperitoneal lymphadenopathy with no hepatomegaly or ascites. Skin biopsy of the right thigh showed granular deposition of IgM and C3 in the superficial vessels of the skin consistent with leukocytoclastic vasculitis. Excisional biopsy of the left axillary lymph node showed a small B-cell lymphoma with plasmacytic differentiation. Flow cytometry demonstrated a CD20 +, CD5-, CD10-, monoclonal population. CD138 staining showed a separate abundant plasma cell population and kappa light chain restriction. Ki 67 was 10 percent. Bone marrow biopsy showed no evidence of disease. These findings are consistent with lymphoplasmacytic lymphoma (LPL).