APRI Calculator
AST to Platelet Ratio Index for liver fibrosis assessment
APRI Calculation
Normal range: 10-40 IU/L (may vary by laboratory)
Most commonly used value is 40 IU/L (default)
Normal range: 150-400 ×10⁹/L
APRI Score Results
Additional Notes:
- •Low APRI score suggests low probability of significant fibrosis
Medical Disclaimer
This APRI calculator is for educational purposes only and should not replace clinical judgment. The APRI score is not sufficiently sensitive to rule out significant disease, especially with mid-range values. Always consult with hepatologists and gastroenterologists for proper liver disease assessment and management. Liver biopsy may still be required for definitive diagnosis.
APRI Score Interpretation
Note: APRI was originally validated in hepatitis C patients but can be used for other liver diseases
Clinical Applications
Non-invasive liver fibrosis assessment
Alternative to liver biopsy screening
Hepatitis C fibrosis staging
Monitoring disease progression
Treatment decision support
Understanding the APRI Score
What is APRI?
The AST to Platelet Ratio Index (APRI) is a simple, non-invasive biochemical marker used to assess liver fibrosis and cirrhosis. It was developed as an alternative to liver biopsy, which is invasive and associated with patient discomfort and potential complications.
Clinical Significance
- •Originally validated in chronic hepatitis C patients
- •Can be used for other fibrotic liver diseases
- •Uses routine laboratory parameters
- •Cost-effective screening tool
APRI Formula
Performance Characteristics
Practical Example
Patient with:
- AST level: 110 IU/L
- AST upper limit: 40 IU/L
- Platelet count: 110 ×10⁹/L
Calculation:
APRI = [2.75 ÷ 110] × 100
APRI = 0.025 × 100
APRI = 2.5
Interpretation: This patient likely has severe fibrosis or cirrhosis.