Carbamylated serum albumin is a risk factor for mortality in patients with end-stage renal disease (ESRD), which may be modifiable with amino acid therapy, according to new research. Urea is known to promote the carbamylation of proteins, including human albumin. Berg et al. found that the proportion of carbamylated serum albumin was twice as high in patients with ESRD than in non-uraemic individuals, and was higher in ESRD patients who died within 1 year than in those who lived longer. In vitro, certain amino acids inhibited the carbamylation of albumin by cyanate.