Assessment of Intracellular Copper Levels

Diagnostic Tests

The American Association for the Study of Liver Diseases (AASLD) recommends liver biopsy with quantitative copper measurement as the definitive test for intracellular copper assessment, directly measuring copper stored within hepatocytes 1, 3, 4
The European Association for the Study of the Liver (EASL) suggests that hepatic parenchymal copper concentration via liver biopsy, with levels >250 μg/g dry weight, provides the best biochemical evidence for copper overload disorders like Wilson's disease 1, 2
Normal hepatic copper levels are <40-50 μg/g dry weight, essentially excluding Wilson's disease in untreated patients 1, 3, 4
Intermediate hepatic copper levels are 70-250 μg/g dry weight, requiring further diagnostic testing, especially with active liver disease 1, 3
Diagnostic hepatic copper levels are >250 μg/g dry weight, providing critical diagnostic evidence for Wilson's disease 1, 2, 4

Use a disposable suction or cutting needle (Jamshidi or Tru-Cut) and place the specimen dry in a copper-free container 1, 2
Submit at least 1-2 cm of biopsy core length to minimize sampling error 1, 3
Dry the specimen overnight in a vacuum oven or freeze immediately and keep frozen during shipment to the laboratory 1, 2
Paraffin-embedded specimens can also be analyzed for copper content 1, 2

24-hour urinary copper excretion >100 μg/24 hours (1.6 μmol/24 hours) indicates Wilson's disease in symptomatic patients 1, 3, 4, 5
Serum ceruloplasmin levels <50 mg/L strongly suggest Wilson's disease 5
Calculated non-ceruloplasmin-bound (free) copper levels >250 μg/L support Wilson's disease 5
Kayser-Fleischer rings strongly support Wilson's disease when present, though absent in up to 50% of patients with hepatic Wilson's disease 5, 9

Start with serum ceruloplasmin, calculated free copper, and 24-hour urinary copper 5
If diagnosis remains unclear, particularly in younger patients, proceed to hepatic copper quantification via liver biopsy 1, 5
Avoid liver biopsy in cirrhotic patients due to inhomogeneous copper distribution and sampling error 1, 5