Kidney Disease Classification to Include Albuminuria

Yael Waknine

The National Kidney Foundation has updated its chronic kidney disease (CKD) classification system to include cause, glomerular filtration rate (GFR), and albuminuria levels.

The Foundation’s new Kidney Disease Outcomes Quality Initiative guideline, published in the January 2013 issue of Kidney International Supplements, is intended to increase prognostic accuracy by using blood and urine tests together rather than either test alone.

“When you put together a patient’s level of kidney function as assessed by the blood test to estimate [GFR] and the extent of kidney damage based on urine albumin level, you improve prediction of risk for future chronic kidney failure and subsequent cardiovascular events. The updated guideline also guides doctors on the appropriate frequency of monitoring based on GFR and albuminuria categories,” explained Joseph Vassalotti, MD, chief medical officer of the National Kidney Foundation, in a news release.

According to the news release, the foundation is planning to promote the new guidelines via an educational initiative that will include a speaker’s guide and a related digital application intended to help clinicians estimate the relative risk for kidney failure and other adverse events.

“Recent studies on current practice indicate that primary care physicians could more routinely use inexpensive readily available testing for albumin in the urine, for people at risk for kidney disease. The new guideline points out what a powerful predictor of risk and outcomes albuminuria is and so our goal is to encourage primary care physicians to screen those with diabetes, high blood pressure and a family history of kidney disease,” Dr. Vassalotti pointed out in the release.

Additional recommendations outlined in the new guidelines include:

clinicians should use creatinine to estimate GFR but can also use cystatin C to calculate estimated GFR (equations and explanations are provided);
the inclusion of both estimated GFR and albuminuria when evaluating risks for overall mortality, cardiovascular disease, end-stage kidney failure, acute kidney injury, and CKD progression;
the timely referral to a kidney specialist for patients with very low GFR (<15 mL/minute) or very high albuminuria (>300 mg/24 hours); and
the implementation of a multidisciplinary team approach that includes nurses, dieticians, and social workers for managing patients with progressive CKD.

Kidney Int. 2013;Suppl 3:1-150. Table of contents