APRI Score Calculator

APRI Score Calculator for Gastroenterology. For the displayed historical HCV significant-fibrosis interpretation, <0.5 and >1.5 are the lower and upper decision limits; exact limits stay intermediate. These are not universal cirrhosis or hepatitis B thresholds.

For shared guidance on choosing a tool and documenting results, read the clinical calculator workflow.

How this calculator works

APRI = 100 x (AST / laboratory AST upper limit) / platelets in 10^9/L. The displayed historical HCV significant-fibrosis limits are below 0.5 and above 1.5; exact limits stay in the intermediate range.

When to use this calculator

Use within a liver-disease-specific noninvasive assessment pathway. The original HCV study distinguishes significant fibrosis from cirrhosis; its cutoffs must not be transferred unchanged to every liver disease.

Inputs used

  • AST (U/L)
  • Laboratory AST upper limit (U/L)
  • Platelets (10^9/L)

Clinical interpretation

For the displayed historical HCV significant-fibrosis interpretation, <0.5 and >1.5 are the lower and upper decision limits; exact limits stay intermediate. These are not universal cirrhosis or hepatitis B thresholds.

Worked example

Fictional teaching case. AST (U/L): 90; Laboratory AST upper limit (U/L): 40; Platelets (10^9/L): 100. Result: 2.25. Above historical upper cutoff. Use an etiology- and population-appropriate sequential assessment. Acute illness and nonhepatic changes in platelets or enzymes can mislead; no score confirms or excludes fibrosis by itself.

Limitations and safety notes

These are not universal cirrhosis, hepatitis B or treatment thresholds. A supplied laboratory upper limit is required; no assumed value is inserted. Use an etiology- and population-appropriate sequential assessment. Acute illness and nonhepatic changes in platelets or enzymes can mislead; no score confirms or excludes fibrosis by itself.

Frequently asked questions

Does APRI above a cutoff automatically trigger cancer surveillance?

No. Surveillance decisions require an established disease-specific indication, not an isolated APRI value.

What can change the meaning of this result?

These are not universal cirrhosis, hepatitis B or treatment thresholds. A supplied laboratory upper limit is required; no assumed value is inserted. Use an etiology- and population-appropriate sequential assessment. Acute illness and nonhepatic changes in platelets or enzymes can mislead; no score confirms or excludes fibrosis by itself.

References

  • Original chronic hepatitis C APRI derivation. https://pubmed.ncbi.nlm.nih.gov/12883497/
  • University of Washington APRI calculation and interpretation context. https://www.hepatitisc.uw.edu/page/clinical-calculators/apri

Editorial review and citation methodology

Maintained by the Quick Medical Calculator Editorial Team. Content record date: September 9, 2026. A content date is not evidence of independent clinical review. Individual clinical sign-off is not recorded on this page.

  • Prefer original validation studies for scoring systems and prediction tools.
  • Use current specialty society guidance, transplant allocation policy, public health guidance, or regulator resources when they govern clinical use.
  • Include limitations and safety notes when a calculator is population-specific, context-dependent, or unsuitable as a standalone decision tool.

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