[Non-secretory primary plasma cell leukemia with hyperammonemia].

A 78-year-old man was admitted because of lumbago and chest pain. A diagnosis of non-secretory primary plasma cell leukemia was made based on the laboratory findings and his history. However, the plaque-forming cells assay of bone marrow cells revealed secretion of monoclonal immunoglobulin from the myeloma cells. Hyperammonemia was detected in the serum. Although the patient was treated with 4 courses of combination chemotherapy (vincristine, adriamycin, cyclophosphamide, methylprednisolone), he died of respiratory failure five months after diagnosis. Autopsy showed widespread multiple myeloma and prominent infiltration of myeloma cell in the sinusoid of the liver. Recently, there have been a few reports which increased the plasma ammonia concentration with multiple myeloma. This report strongly suggested that liver infiltration of myeloma cell caused hyperammonemia.