Table of Contents
📘 Standard Pediatric Definition (Nelson Textbook of Pediatrics)
👉 Acute Liver Failure (ALF) is defined as:
Evidence of acute liver injury in a child with no pre-existing chronic liver disease, accompanied by hepatic-based coagulopathy (INR ≥1.5 with encephalopathy OR INR ≥2.0 without encephalopathy), not corrected by vitamin K.
🔑 Key Components to Remember
1. Acute liver injury
- Elevated transaminases (AST/ALT)
- Recent onset (days to weeks)
2. No prior chronic liver disease
- Important to differentiate from acute-on-chronic liver failure
3. Coagulopathy (core criterion)
- INR ≥1.5 + encephalopathy
OR - INR ≥2.0 without encephalopathy
- Must be unresponsive to vitamin K
4. Encephalopathy (may be absent in children)
- Unlike adults, pediatric ALF does NOT require encephalopathy for diagnosis
🧠 Exam Pearls (Very Important)
- Coagulopathy is mandatory
- Encephalopathy is NOT mandatory in pediatrics
- Always mention vitamin K non-correction
🧾 One-line Answer for Exams
👉 “Acute liver failure is acute hepatic injury without prior liver disease, with INR ≥1.5 with encephalopathy or ≥2 without encephalopathy, not corrected by vitamin K.”
