[Development of evaluation of kidney function and classification of chronic kidney disease (CKD)--including CKD...

Area of Science:

• Nephrology
• Clinical Practice Guidelines
• Biomarkers

Context:

• The 2012 Japanese Chronic Kidney Disease (CKD) Clinical Practice Guide (CKD guide 2012) was developed to update the 2009 version.
• CKD classification was revised to align with the KDIGO 2012 CKD Clinical Practice Guideline, incorporating cause, glomerular filtration rate (GFR) categories, and albuminuria categories.
• Proteinuria categories were added to the CKD Guide 2012 to complement albuminuria categories, addressing the less common evaluation of albuminuria in Japan.

Purpose:

• To update the clinical practice guidelines for managing Chronic Kidney Disease in Japan.
• To integrate the KDIGO 2012 classification system, including GFR and albuminuria categories.
• To introduce and recommend new methods for estimating GFR, particularly those less influenced by muscle mass.

Summary:

• The CKD guide 2012 adopted the KDIGO 2012 classification based on cause, GFR, and albuminuria.
• Proteinuria categories were included as a proxy for albuminuria assessment in the Japanese population.
• The guide recommends GFR equations based on serum creatinine (eGFRcreat) and serum cystatin C (eGFRcys), with a new equation for Japanese individuals using standardized cystatin C.
• eGFRcys is highlighted as being less affected by muscle mass variations compared to eGFRcreat.
• The average of eGFRcreat and eGFRcys (eGFRaverage) is proposed as the most accurate estimation of GFR.

Impact:

• Facilitates more accurate diagnosis and staging of CKD in Japan by adopting international standards.
• Improves GFR estimation accuracy, particularly in patient populations with varying muscle mass, leading to better clinical decision-making.
• Provides clinicians with updated tools and recommendations for managing CKD patients effectively.