Pathology Findings in a Model of Auxiliary Liver Transplantation With Portal Vein Arterialization in Pigs

Abstract

Objective To determine the histological findings and temporal evolution that occur in auxiliary liver grafts as a consequence of arterialization of the portal vein (PVA). Materials and methods We evaluated 10 auxiliary heterotopic liver transplants with arterialization of the PVA. The histological study was performed using an optical microscope to process liver samples with staining using hematoxylin and eosin. A biopsy of native liver tissue was used as a control. Results Two animals were excluded from the study, one due to ischemic necrosis of the graft and one that died 4 hours after transplant. All of the remaining eight animals underwent a histological study at 1 day, 7 days, and 14 days. The most significant histological findings were: (1) dilation of portal areas and sinusoids, which were detected at 24 hours and persisted; (2) thickening of the interlobular septum, which was observed after day 7 and progressively increased to day 14; (3) bile duct hyperplasia detected at the seventh day. Conclusions The consistent, early findings in a pig liver with PVA included vascular dilation of the portal area and the sinusoids, with bile duct hyperplasia extending progressively and the thickening of interlobular connective tissue septa with a generalized perilobular connective tissue reaction, which did not seem to alter the internal structure of the lobule, which showed histologically normal hepatocytes. The fibrous reaction may be the first stage in chronic hepatopathy. Further long-term studies are required in this model.