[Plasma cell acid phosphatase in the differential diagnosis of monoclonal gammopathies]

Acid phosphatase activity was studied cytochemically in bone marrow plasma cells of 32 multiple myelomas, 45 non-myelomatous monoclonal gammopathies and 20 normal subjects. We have found significant differences among these three groups (P less than 0.001). The usefulness of this cytochemical reaction for the study of monoclonal gammopathies is discussed.