Acute phase reactant proteins in differential diagnosis of monoclonal gammopathy.

The serum levels of five individual serum proteins, i.e. ceruloplasmin, alpha 1-antitrypsin, orosomucoid, haptoglobin and transferrin, were studied in 55 multiple myeloma (MM) patients, in 34 essential monoclonal gammopathy (EMG) patients, in 14 EMG patients excluded for active inflammatory process and in 14 healthy control subjects. Transferrin--negative acute phase reactant (APR)--was significantly decreased and the remaining proteins under study--positive APR--slightly increased in the EMG group compared with healthy controls. Transferrin and ceruloplasmin levels were significantly different when the MM was compared to the EMG group so that these parameters might be useful in differential diagnosis between both groups. In the MM clinical stage III, the differences are even more significant. In the IgG3 MM the APR levels seem to be more significantly changed than in the IgG1 and IgG2 MM. In EMG patients with active inflammatory process who were excluded ceruloplasmin, alpha 1-antitrypsin, orosomucoid and haptoglobin were significantly increased when compared with the EMG group.