Advanced CKD after AKI Risk Index

This risk calculator was derived using over 9,000 patients with baseline eGFR ≥45 mL/min/1.73m² who were hospitalized in Alberta, Canada with acute kidney injury (AKI), and was used to predict advanced CKD (sustained eGFR < 30 mL/min/1.73m²) in the subsequent year after discharge from hospital. The models were internally validated in a cohort from Alberta, Canada, and externally validated in a cohort from Ontario, Canada.

Discharge serum creatinine (Scr) is categorized into 5 levels

• <1.0 mg/dL or <88 μmol/L
• 1.0 - <1.3 mg/dL or 88 - <114 μmol/L
• 1.3 - <1.6 mg/dL or 114 - <141 μmol/L
• 1.6 - <1.9 mg/dL or 141 - <167 μmol/L
• ≥1.9 mg/dL or ≥167 μmol/L

Acute kidney injury (AKI) severity is determined by comparing peak serum creatinine during hospitalization with baseline creatinine according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria.

AKI stage 1 if Scr increased by ≥0.3 mg/dL (≥26 μmol/L) or peak Scr was 1.5-1.9 times baseline Scr

AKI stage 2 if peak Scr is 2.0-2.9 times baseline Scr

AKI stage=3 if peak Scr ≥3.0 times baseline or peak Scr increased to ≥4.0 mg/dL (≥354 μmol/L), or a patient is treated with dialysis during hospitalization.

Albuminuria is categorized as

• normal (ACR <30 mg/g [<3.4 mg/mmol] or urine dipstick negative),
• mild (ACR 30-300 mg/g [3.4-34 mg/mmol] or urine dipstick trace or 1+), or
• heavy (ACR > 300 mg/g [≥34 mg/mmol] or urine dipstick ≥ 2+).