Conditions for albumin dimerisation in hephrotic urines. Dependence on an ultrafilterable factor

At--14 degrees C the albumin in the urine of some patients with a nephrotic syndrome polymerises into dimer and higher polymers. This occurs at low ionic strengths within 1-3 days and in the pH range 5-10. For polymerisation both an altered albumin molecule and a low molecular weight ultrafilterable fraction in the urine are necessary. The appearance of both is probably related to steroid therapy. The ultrafiltrate fraction has molecular mass < 700, and is not peptide, amino acid, fatty acid or highly charged ion.