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🫀 APRI (AST to Platelet Ratio Index)

UseTriage for fibrosis/cirrhosis where elastography is unavailable.

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SourceWai CT, et al. Hepatology 2003

Runs locally in your browser (no PHI uploaded). For licensed clinicians — not a substitute for clinical judgement.
Stored on this device for revisit reminders

This-shift next steps

After scoring: open the scene pack, peer scores, and the matching pathway. Local reference — no HIS write.

Score + version; reference only — not a substitute for care · no HIS write

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Methodology · worked example, guidelines & full notes
Clinical takeaway

WHO uses APRI > 2 as a cirrhosis cut-off in resource-limited settings.

When to use

Triage for fibrosis/cirrhosis where elastography is unavailable.

How it works

APRI = (AST/ULN × 100) / platelets (×10⁹/L). > 1.0 suggests significant fibrosis; > 2.0 suggests cirrhosis.

Key points

  • WHO uses APRI > 2 as a cirrhosis cut-off in resource-limited settings.
  • Developed in hepatitis C — performance varies by aetiology.
  • Confirm with imaging/elastography where possible.

References

Worked calculation

The values below come from this tool's own example placeholders and are computed server-side with the formula shown on this page, so the arithmetic can be checked quickly. It demonstrates how to substitute values only — it is not clinical advice and not a real case.

AST80 U/L
AST upper limit of normal40 U/L
Platelets150 ×10⁹/L

→APRI1.33

  • Interpretation:> 1.0 — suggests significant fibrosis
  • Formula:(AST/ULN × 100) / platelets (×10⁹/L)
Verification & sources · governance
FAQ

Frequently asked questions

What are the limits and cautions when using APRI (AST to Platelet Ratio Index)?
For licensed clinicians and clinical researchers. Interpret results with history, investigations and local protocols; not a diagnosis or prescription, and not a substitute for multidisciplinary decision-making or local guidelines.
Does APRI (AST to Platelet Ratio Index) upload patient data? Where is it calculated?
Calculation runs locally in the browser; inputs and results are not uploaded. For licensed clinicians only; interpret with history, investigations and local protocols — not a diagnosis or prescription.
How is APRI (AST to Platelet Ratio Index) calculated in practice? Can you show a worked example?
Inputs: AST 80 U/L, AST upper limit of normal 40 U/L, Platelets 150 ×10⁹/L → Result: APRI 1.33(Interpretation: > 1.0 — suggests significant fibrosis, Formula: (AST/ULN × 100) / platelets (×10⁹/L))
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