Diagnostic histochemistry in hepatic pathology.

Histochemistry has an important, continuing role in the current assessment of hepatic biopsies and resection specimens. The evaluation of connective tissue elements in the liver can be accomplished with such methods as the Masson trichrome, Snook reticulin, Vierhoff van Gieson, orcein, and Victoria blue stains. The results contribute to the diagnosis of acute and chronic hepatitis, submassive necrosis, venous outflow obstruction, steatohepatitis, and cirrhosis. Fat stains done on frozen sections of liver tissue are routinely performed in the evaluation of donor liver allograft biopsies. Iron stains such as Perls' method and the Prussian blue technique contribute to the recognition of hemochromatosis and hemosiderosis. The rhodanine, orcein, and Timm stains for copper are used in the characterization of chronic cholestatic liver disease and Wilson's disease. Labeling of carbohydrate-based moieties in various disorders is accomplished with the digested and undigested periodic acid-Schiff method, and Congo red or crystal violet stains can be employed to detect amyloid deposition. Lastly, evaluations of the thickness of the cell plates and continuity of the reticulin framework, as seen with the Snook reticulin stain, can contribute to the diagnostic separation of benign from malignant hepatocellular neoplasms.