Update on diagnostic and prognostic biomarkers for diabetic nephropathy

Diabetic kidney disease (DKD) is a common complication of diabetes mellitus that, if diagnosed too late or treated inadequately, leads to end-stage renal disease and requires dialysis. Classically, DKD is diagnosed by quantification of albuminuria. The lack of tubuloglomerular feedback in diabetic kidney disease is associated with glomerular hyperfiltration and increased glomerular pressure, resulting in structural changes that can be detected before the onset of albuminuria. These early impairments cannot be detected with conventional diagnostic tools and therefore may delay therapeutic intervention. In addition, there are non-albuminuric subtypes of diabetic kidney disease that result in worsening renal function without the presence of albuminuria. Therefore, there is a need for new diagnostic markers that can detect diabetic nephropathy before albuminuria occurs. Recently, several glomerular and tubular biomarkers have been investigated to indicate early diabetic kidney disease. In this context, liquid biopsies representing a pattern of multiple biomarkers are a promising tool.