ALB and chronic kidney disease: Because albuminuria and GFR are key in classifying CKD, the Kidney Disease: Improving Global Outcomes guidelines also assess its severity using the albumin-to-creatinine ratio (ACR).6 The combination of GFR and albuminuria based on the Kidney Disease: Improving Global Outcomes guidelines is used to determine the severity of CKD and guide clinical decision-making (Figure 1).