Chapter 100: Liver Transplantation Pathology

Normal portal tract. The normal portal tracts consist of the portal triad (vein, artery, and bile duct) contained by fibrous tissue, with mild inflammation, apparent on H&E. There is a sharp demarcation between the portal tract and the surrounding hepatic parenchyma. In adults, the normal liver cell plates are one cell thick.

Normal portal tract. Trichrome stain highlights the demarcation between the portal tract and the hepatic parenchyma (the interface). Trichrome stain is useful in demonstrating the important finding of fibrosis, as may be seen in the setting of chronic injury.

Normal portal tract. Cytokeratin 7 (CK7) stain highlights biliary epithelium. Normal portal tracts contain a single bile duct, although it may be seen in multiple cross-sections. Rare portal tracts may lack an apparent bile duct in a normal liver. CK7 is useful in demonstrating bile duct injury and loss, as may be seen in cellular rejection, as well as proliferation of new ductules in various pathologic conditions.

Normal lobule. There is a small amount of collagen surrounding the central vein. H&E highlights regularly spaced liver cells without significant inflammation.

Normal lobule. Liver cells radiating outward from a central vein in an orderly fashion are highlighted on reticulin stain. Besides demonstrating increased fibrosis, reticulin stain may be helpful for demonstrating abnormal thinning or thickening of liver cell plates.

Freezing artefact: steatosis. Frozen-section analysis of liver. Freezing may produce an artefact that mimics hepatocellular steatohepatitis.

Permanent section of the tissue seen in Fig. 100-6; the apparent steatosis is no longer seen. Examination of multiple levels, correlation with touch preparation, and discussion with the surgical team are helpful to avoiding this pitfall.

Freezing artefact: necrosis. Assessment of liver for necrosis may be requested in both donor livers, particularly those in which there is suspicion for ischemic or hypotensive injury, and in recently transplanted allografts. Necrosis may be subtle on frozen section. Eosinophilic regions may be identified in comparison to viable liver (necrosis is seen centrally in this image). Correlation with transaminases, if available, may be helpful.

Saline immersion artefact. These are most commonly seen in intraoperative biopsies, which may be performed during reoperation for any reason. If specimens are immersed in saline, artifactual dissolution ...