How can BJP be quantified?
A value can be obtained by scanning densitometric analysis of the stained electrophoretic separation and relating this to the total urine protein. When BJP is present, without other overt proteinuria, the total protein is an estimate of the BJP. However, this method is generally unreliable. Paraprotein bands can also be quantitated directly from capillary zone electrophoretic (CZE) separations. There is no International Reference Preparation for urinary light chains, and there will be marked variations in reactivity of antisera with monoclonal light chains. For this reason immunochemical methods of quantitation of BJP are not recommended (Riches PG, Sheldon, J., Smith, AM, Hobbs, JR (1991) Annals of Clinical Biochemistry, 28, 253-259).
