Researchers in Germany have identified six metabolites that show strong correlations with kidney function. The study, “A Metabolome-wide Association Study of Kidney Function and Disease in the General Population,” appears online in Journal of the American Society of Nephrology.

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.

Anna Köttgen, MD, MPH, Peggy Sekula, PhD from the University of Freiburg in Germany, Gabi Kastenmüller PhD, from the Helmholtz Center Munich and their colleagues measured the concentrations of almost 500 metabolites in the blood of several thousand individuals from the general population.

Six metabolites showed strong correlations with kidney function, and two 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.