Human plasma is a complex solution containing many proteins, probably hundreds, some of which are present only in trace quantities. The distribution of these proteins in the normal adult shows an amazing degree of uniformity. However, in disease states considerable variation in the quantity of the individual plasma protein components takes place, which is referred to as dysproteinemia. Less frequently, certain qualitatively abnormal proteins may develop as a response to disease, and these proteins are referred to as paraproteins.
These variations in plasma proteins in disease have intrigued clinicians since the early salt fractionation of human serum at the turn of the century. In 1921, Howe,1 utilizing 21.5% sodium sulfate as a simple method of fractionation, precipitated a protein from serum which was defined as "albumin." This quantity of "albumin" subtracted from the total serum proteins (corrected for nonprotein nitrogen) represented "globulin." These two fractions related to the total