Certain blood markers may indicate early signs of kidney disease

Chronic kidney disease (CKD) is a major public health challenge, affecting approximately 10% of adults and contributing to kidney failure, heart disease, and premature death. While it is important to identify individuals with CKD early on in order to prevent complications, measures of kidney function are usually based on the blood concentrations of the metabolite creatinine, which only start to become elevated after 50% of the kidneys' function has already been lost. In addition, creatinine concentrations are influenced by other factors such as muscle mass.

To look for better markers of kidney function, Anna Köttgen, MD, MPH, Peggy Sekula, PhD (University of Freiburg, Germany), Gabi Kastenmüller PhD (Helmholtz Center Munich, Germany), and their colleagues measured the concentrations of almost 500 metabolites in the blood of several thousand individuals from the general population. (Metabolites are generated through ongoing metabolic processes and many are cleared from the body by the kidneys. When the function of the kidneys is impaired, the concentrations of these metabolites in the blood may increase.)

Six of the metabolites showed particularly strong correlations with kidney function. In addition, 2 of the metabolites -- pseudouridine and C-mannosyltryptophan -- were equally good measures of kidney function and disease progression in patients with CKD compared with creatinine.

"These markers therefore represent promising candidates to further improve the estimation of kidney function by combining them with information on creatinine concentrations. This will facilitate an improved diagnosis of CKD, enabling treatment and prevention of complications," said Dr. Köttgen.