Determination of urinary protein fractions. A comparison with different electrophoretic methods and quantitatively...

The second morning urine of 207 patients with various renal diseases was examined. After testing the urine with the Combur-9-RL((R)) dip strip, the concentrations of total protein, creatinine, albumin, alpha-1-microglobulin, immunoglobulin G and transferrin were determined. The urinary protein fractions were measured in parallel with the electrophoresis kits: Hydragel-Proteinuria (sebia GmbH, Fulda); Protur-HiSi (Beckman Coulter GmbH, Krefeld); SPE-II (Beckman Coulter) and the protein concentrations were calculated. The method comparison was based on the agreement of the ascertained types of proteinuria, and on comparison of the electrophoretically obtained albumin protein concentrations with the automated concentration results. It could be shown that urine electrophoresis is a reliable analytic method for the diagnosis of proteinurias. A good agreement and significant correlations were found between single protein determination and urinary electrophoresis. A diagnostic strategy that combines electrophoresis, single protein determination and immunofixation is useful for the diagnosis and differentiation of proteinuria.