Dx-Wilson disease
↑ 24-h urine Cu, ↓ serum ceruloplasmin (Se 90%), liver bx w/ hepatic Cu content, genetic testing for ATP7B gene helpful if unclear dx. In acute liver failure, Aϕ/bili <4 + AST/ALT >2.2 better Se & Sp than urine Cu or ceruloplasmin (Hepatology 2008;4:1167).