APRI (AST to Platelet Ratio Index)
AST-to-platelet ratio index (Wai 2003) = (AST/AST-ULN)*100/platelets.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- AST
- 60 U/L
- AST upper limit of normal
- 40 U/L
- Platelets
- 150 x10^9/L
Result: APRI 1.00 - predicts significant fibrosis per Wai 2003 (WHO 2014 HCV guideline endorsement).
The tool opens with these values already filled in. Replace them with your own.
What the result means
- <=0.7
- Below the Wai 2003 significant-fibrosis cutoff.
- >0.7
- Predicts significant fibrosis per Wai 2003 (WHO 2014 HCV guideline endorsement).
- >1.0
- Predicts cirrhosis per Wai 2003 (WHO 2014 HCV guideline endorsement).
What you enter
- AST
- AST upper limit of normal
- Platelets
How this is calculated
Wai CT, Greenson JK, Fontana RJ, et al. A simple noninvasive index can predict both significant fibrosis and cirrhosis in patients with chronic hepatitis C. Hepatology. 2003;38(2):518-526. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.