72例多发性骨髓瘤单克隆蛋白分析

用速率散射比浊法测定 72例多发性骨髓瘤 (MM)血清与尿中单克隆蛋白 (M蛋白 )。结果显示 ,与IgG型 ,IgA型对应的免疫球蛋白 (Ig)均显著增高 ,不对应的Ig均明显降低。无论κ或λIgG ,IgA型 ,其对应的血清轻链显著增高 ,不对应的血清轻链显著降低。无论LC κ或是LC λ型 ,对应的血轻链在正常范围 ,不对应的血轻链低于正常 ,而尿中对应的轻链显著增高。在IgG ,IgA ,LC三型中 ,血清与尿中轻链κ/λ均显著异常。提示 ,血清中κ轻链 >2 0g·L 1或 <5g·L 1,λ轻链 >10g·L 1或 <2g·L 1,血、尿中κ/λ >5或 <0 .75时 ,任一项指标对MM的诊断均具有重要价值。

Analysis of monoclonal protein in 72 cases of multiple myeloma

Serum and urinary monoclonal proteins (M protein) were measured in 72 cases of multiple myeloma (MM) using rate nephelometry. In IgG and IgA types of MM, the level of immunoglobulin (Ig) corresponding to the malignant isotype was significantly higher and that of Ig uncorresponding to the malignant isotype lower than the normal level. The light chain corresponding to the malignant isotype in serum was increased and the light chain uncorresponding to that in serum was decreased either kappa-IgG, IgA types or lambda-IgG, IgA types. Either kappa-LC or lambda-LC type of MM, the serum light chain corresponding to the malignant isotype was in the normal range and uncorresponding to that was decreased,and the corresponding light chain in urine was significantly elevated. Kappa/lambda ratio in serum and urine was all significantly abnormal in IgG, IgA, and LC types of MM.Our data suggest that any quota among kappa light chain>20 g.L-1　or<5 g.L-1,lambda light chain>10 g.L-1 or<2 g.L-1　in serum and kappa/lambda ratio>5 or<0.75 in serum and urine has an important value for diagnosing MM.