Cystatin C May Help Better Assess Kidney Impairment.

MedPage Today  (7/6, Gever) reports, "Using cystatin C levels along with serum creatinine to estimate the glomerular filtration rate (GFR) did a better job of assessing kidney impairment than the standard GFR formula," according to a study  (pdf) published in the New England Journal of Medicine. Investigators found that "substantially more patients were correctly classified as having GFR values above or below the critical threshold of 60 ml/min/1.73 m2 when it was estimated with the combined method versus the conventional GFR calculation that relies only on serum creatinine."