AST to Platelet Ratio Index (APRI)
Non-invasive marker of hepatic fibrosis and cirrhosis, most validated in chronic hepatitis C. Also used in NAFLD, hepatitis B, and alcoholic liver disease.
Score interpretation
APRI ≤ 0.5: significant fibrosis (≥ F2) unlikely.
→ Low likelihood of significant fibrosis. Annual monitoring of LFTs and platelets. Treat underlying cause (HCV: DAA therapy; NAFLD: lifestyle).
APRI 0.5–1.0: indeterminate for significant fibrosis; cirrhosis unlikely (≤ 1.0 rules it out, WHO 2014).
→ Stage with transient elastography (FibroScan) or FIB-4; treat the underlying cause.
APRI 1.0–1.5: indeterminate for both significant fibrosis and cirrhosis.
→ Hepatology referral; transient elastography (FibroScan) to stage; treat the underlying cause.
APRI above 1.5: significant fibrosis (≥ F2) likely; cirrhosis indeterminate (1.0–2.0).
→ Hepatology review. Non-invasive staging (FibroScan). Liver biopsy if discordant results.
APRI above 2.0: cirrhosis likely (WHO 2014 rule-in cut-off).
→ Hepatology referral. FibroScan or biopsy to confirm. Cirrhosis monitoring: 6-monthly USS + AFP for HCC, endoscopy for varices, clinical staging.
Interpretation bands for the APRI. Apply clinical judgement and local guidance.
References
- Wai CT, 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.
- World Health Organization. Guidelines for the screening, care and treatment of persons with hepatitis C infection. Geneva: WHO; 2014.
Related
Curated clinical cross-links plus same-class fallbacks.
- Spironolactone (Ascites / Cirrhosis) · Aldosterone Antagonist / Potassium-Sparing Diuretic
- Furosemide (Ascites / Cirrhosis) · Loop Diuretic
- Entecavir · Antiviral — Hepatitis B (Nucleoside Analogue)
- Tenofovir (TDF/TAF) · Antiviral — Hepatitis B (Nucleotide Analogue)
- Glecaprevir / Pibrentasvir · Antiviral — Hepatitis C (Pan-Genotypic DAA)
- Sofosbuvir / Velpatasvir · Antiviral — Hepatitis C (Pan-Genotypic DAA)
- Upper GI Bleeding · BSG Guidelines 2019; NICE NG141
- Lower Gastrointestinal Bleed · NICE; BSG; ACPGBI — Commissioning Guide
- Acute Pancreatitis · NICE; IAP/APA; ACPGBI — CG104
- Sepsis Screening and Sepsis Six · UK Sepsis Trust; NICE NG51; Surviving Sepsis Campaign 2021
- Unintentional Weight Loss Workup · NICE NG12; BSG
- Chronic Fatigue Workup · NICE NG206; BMJ Best Practice
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.