SODIUM DODECYL SULFATE-AGAROSE GEL-ELECTROPHORESIS OF URINARY PROTEINS - APPLICATION TO MULTIPLE-MYELOMA

We evaluated a new sodium dodecyl sulfate-agarose gel electrophoresis (SDS-AGE) for urinary protein analysis in patients with multiple myelo ma (MM; n = 47; ages, 62 +/- 2 years, mean +/- SE). Abnormal proteinur ia (mean = 1872 +/- 360 mg/24 h) was present in 95% of the samples; 75 % of the patients had some sign of renal dysfunction (glomerular and/o r tubular) according to their SDS-AGE pattern. A band suggesting Bence Jones proteinuria (BJP) was detected in 40 vs 33 specimens by routine AGE. Immunofixation identified BJP in 38 patients; the calculated sen sitivity of SDS-AGE for BJP was 97%. Excellent correlation (P < 0.0001 ) was obtained with routine AGE (r = 0.994) and immunonephelometry (r = 0.963) for light chain quantification. SDS-AGE allows easy evaluatio n of renal dysfunction and shows high sensitivity for BJP detection. I n a specialized laboratory, it is useful for following the progress of MM patients through the semiquantification of BJP.