Liver rejection is one complication that can arise after a liver transplant. Pathology can be performed on liver transplant biopsies to determine the cause of abnormal or impaired functioning, assess the effectiveness of rejection therapy on patients with rejection, and also determine the need for retransplantation. A factor that aides the pathologist in determining transplant rejection is the time between the liver transplant and the manifestation of liver dysfunction. Rejection and technical complications will normally arise soon after transplantation, whereas infections or drug reactions may occur at any time interval after transplantation.
One histologic characteristic of liver transplant rejection is interlobular bile duct damage. When a liver is transplanted, many anastomoses (connections) must be made, including connection to the biliary system. Another histologic characteristic of liver transplant rejection is significant damage to the endothelium visualized as endothelial cell enlargement and detachment from underlying collagen. Variables that assist in diagnosis of liver transplant rejection in liver biopsy tissue is adequate biopsy size, presence of at least four portal tracts as to visualize bile duct damage, and presence of at least four central veins. These variables demonstrate the importance for the histotechnologist to provide three step sections of the biopsy. Adequate representation of the liver biopsy tissue is crucial to assisting the pathologist in determining the etiology of the liver dysfunction.