A note on Urine Albumin-to-Creatinine Ratio (UACR) 

The addition of albuminuria staging to GFR staging is relatively a new endeavor, added for further micromanaging and to identify patients with renal disease relatively earlier. Another advantage of this staging is use of a spot urine albumin-to-creatinine ratio (UACR). 24 hour collection is not necessary.

 Urine albumin (mg/dL) / Urine creatinine (g/dL) = UACR in mg/g

Grading is done as per following

1. A1 = UACR less than 30 mg/g 
2.  A2 = UACR 30 to 299 mg/g 
3.  A3 = ACR more than/equal to300 mg/g

 Studies have shown that UACR along with eGFR provide a better predictor of patients at risk for ESRD.



 Reference: 

Hallan SI, Ritz E, Lydersen S, et al. Combining GFR and albuminuria to classify CKD improves prediction of ESRD. J Am Soc Nephrol 2009; 20:1069.