Definition

• Damage to the hepatocytes
• Histological: (lymphocytic) inflammation of liver
• Biochemical: more significant elevation in: Transaminitis

DDx and Test Pattern

1. Mild ALT (< 40) ! elevation (< 300)

   • Mild DDx

   Top 3 Cause	Special Enzyme Pattern	Investigations
   Chronic ‣ (B,C,D)	Mild ALT ↑	Serology
   ‣	Mild ALT ↑ (100-400), AST ↑> ALT ↑ (2:1)	History, ‣
   ‣	Mild ALT ↑	History, ‣, (maybe‣ )

2. Moderate - Severe ALT (< 40) ! elevation (> 1000)

   • Severe DDx

   Top 3 Cause	Special Enzyme Pattern	Investigations
   Acute ‣ (A,B,C,D,E)	Severe ALT ↑	Serology, travel history
   ‣	Severe ALT ↑ (5 x ULN)	Auto-antibody (2x IgG, ANA, SMA, LKM)
   Drug-induced liver injury (‣)	Severe ALT ↑	Toxin screen

Mixed Pattern Liver Disease