Case 35

A 67-year-old man presented with acute low-back pain after moving heavy furniture. Radiography and CT scan demonstrated a collapsed vertebral body at T9 level. Serum electrophoresis demonstrated a monoclonal spike in the gamma region. Immunofixation identified a monoclonal IgG-kappa gammopathy. Quantitation of serum immunoglobulins showed IgG 3.0 g/dl, IgA 80 mg/dl, and IgM 40 mg/dl. Bence Jones protein was present in the urine. His serum calcium level was 12 mg/dl and beta-2 microglobulin level was 11 mg/l. The peripheral blood smear showed rouleaux formation, but no plasma cells were seen (Fig. 35.1). The morphologic features of bone marrow aspirate and biopsy are illustrated in Figs. 35.2 and 35.3, respectively.