Plasma cell acid phosphatase as an adjunct in the differential diagnosis of monoclonal immunoglobulinemias.

Plasma cell acid phosphatase has been studied in 51 patients, 30 of whom were affected with multiple myeloma (MM) and 21 with nonmyelomatous monoclonal immunoglobulinemias (NMMI). Scoring of results displayed a highly significant difference between the median of the MM and NMMI group (343 vs. 204). The use of plasma cell acid phosphatase as a further criterion in the differential diagnosis of monoclonal immunoglobulinemiasis emphasized.