Published online Dec 15, 2014. doi: 10.4239/wjd.v5.i6.763
Revised: October 3, 2014
Accepted: October 23, 2014
Published online: December 15, 2014
Diabetic nephropathy (DN) is the leading cause of end stage renal disease in the Western world. Microalbuminuria (MA) is the earliest and most commonly used clinical index of DN and is independently associated with cardiovascular risk in diabetic patients. Although MA remains an essential tool for risk stratification and monitoring disease progression in DN, a number of factors have called into question its predictive power. Originally thought to be predictive of future overt DN in 80% of patients, we now know that only around 30% of microalbuminuric patients progress to overt nephropathy after 10 years of follow up. In addition, advanced structural alterations in the glomerular basement membrane may already have occurred by the time MA is clinically detectable.Evidence in recent years suggests that a significant proportion of patients with MA can revert to normoalbuminuria and the concept of nonalbuminuric DN is well-documented, reflecting the fact that patients with diabetes can demonstrate a reduction in glomerular filtration rate without progressing from normo-to MA. There is an unmet clinical need to identify biomarkers with potential for earlier diagnosis and risk stratification in DN and recent developments in this field will be the focus of this review article.
Core tip: Microalbuminuria (MA) is the earliest and most commonly used clinical index of diabetic nephropathy (DN), however its sensitivity and specificity for early disease detection are limited. Not all patients with MA progress to overt DN, nonalbuminuric DN is common and risk associated with MA is elevated even at levels below currently accepted diagnostic thresholds. There is therefore a need for alternative biomarkers allowing early identification of “at risk” individuals. This review focusses on biomarkers of glomerular and tubular dysfunction, oxidative stress and inflammation that have attracted interest. In addition we review more novel strategies including proteomic, metabolomic and genomic approaches.