In the earlier stages of the disease, the biopsy typically shows steatosis (deposition of fatty material), increased glycogen in the nucleus, and areas of necrosis (cell death). In more advanced disease, the changes observed are quite similar to those seen in autoimmune hepatitis, such as infiltration by inflammatory cells, piecemeal necrosis, and fibrosis (scar tissue). In advanced disease, finally, cirrhosis is the main finding. In acute liver failure, degeneration of the liver cells and collapse of the liver tissue architecture is seen, typically on a background of cirrhotic changes. Histochemical methods for detecting copper are inconsistent and unreliable, and taken alone are regarded as insufficient to establish a diagnosis.
