Skin autofluorescence: an emerging biomarker in persons with kidney disease.
PURPOSE OF REVIEW: Skin autofluorescence (SAF) is a measure of the accumulation of advanced glycation end-products (AGEs) proposed to act as a marker of 'cumulative metabolic stress'. This article discusses mechanisms of AGE formation and reviews published literature on SAF as a biomarker and risk factor across the spectrum of kidney disease. RECENT FINDINGS: SAF is elevated in adults and children on dialysis. Higher SAF is an independent risk factor for cardiovascular and all-cause mortality in persons receiving haemodialysis and for all-cause mortality in persons performing peritoneal dialysis, though the increase in discrimination when SAF was added to traditional risk factors was modest. In less advanced chronic kidney disease, higher SAF predicts all-cause mortality and progression. SAF is elevated in renal transplant recipients, but to a lesser extent than in dialysis patients. In one study, higher SAF predicted graft loss and mortality. SAF has been reported to be increased in patients with acute kidney injury. SUMMARY: A growing body of evidence attests that SAF, a marker of AGE accumulation, is a risk factor for mortality and kidney function decline in multiple types of kidney disease. Further studies are warranted to evaluate interventions to reduce SAF and the impact on clinical outcomes.