Departments of Surgery, Erasmus University Medical Center, Rotterdam, the Netherlands.
Liver Transpl. 2013 Oct;19(10):1088-98. doi: 10.1002/lt.23701. Epub 2013 Aug 13.
Ischemic-type biliary lesions (ITBLs) are a major cause of morbidity after liver transplantation (LT). Their assumed underlying pathophysiological mechanism is ischemia/reperfusion injury of the biliary tree, in which the portal circulation has been proposed recently to have a role. The aim of this study was to investigate whether early histological changes, particularly in the portal vein, predispose patients to ITBLs. A case-control study of 22 LT recipients was performed through a retrospective assessment of more than 30 histological parameters in 44 intraoperative liver biopsy samples taken after cold ischemia (time 0) and portal reperfusion (time 1). Eleven grafts developed ITBLs requiring retransplantation (the ITBL group), and 11 matched controls had normally functioning grafts 11 years after LT on average (the non-ITBL group). Additionally, 11 liver biopsy samples from hemihepatectomies performed for metastases of colorectal cancer (CRC) were assessed similarly. Analyses showed no significant histological differences at time 0 between the ITBL and non-ITBL groups. However, the time 1 biopsy samples from the ITBL group showed smaller portal vein branches (PVBs) significantly more often than the samples from the non-ITBL group, which also showed persisting paraportal collateral vessels. Larger PVBs and paraportal collateral vessels were also found in the CRC group. A morphometric analysis confirmed these findings and showed that PVB measurements were significantly lower for the ITBL group at time 1 versus the ITBL group at time 0 and the non-ITBL and CRC groups (they were largest in the CRC group). Thus, the PVB dimensions decreased in the ITBL group in comparison with the time 0 biopsy samples, and they were significantly smaller at time 1 in comparison with the dimensions for the non-ITBL and CRC groups. In conclusion, a smaller PVB lumen size in postreperfusion biopsy samples from liver grafts, suggesting a relatively decreased portal blood flow, is associated with a higher incidence of ITBLs. These findings support recent clinical studies suggesting a possible pathophysiological role of portal blood flow in the oxygenation of the biliary tree after LT.
缺血型胆道病变（ITBLs）是肝移植（LT）后发病率的主要原因。其假设的潜在病理生理机制是胆道的缺血/再灌注损伤，最近提出门脉循环在此过程中起作用。本研究旨在探讨门静脉的早期组织学变化是否会使患者易发生 ITBLs。通过对 44 份冷缺血（时间 0）和门静脉再灌注（时间 1）后术中肝活检样本的 30 多个组织学参数进行回顾性评估，对 22 例 LT 受者进行了病例对照研究。11 例移植物发生需要再次移植的 ITBL（ITBL 组），11 例匹配的对照组在 LT 后 11 年平均功能正常的移植物（非 ITBL 组）。此外，还对 11 例因结直肠癌（CRC）转移而行半肝切除术的肝活检样本进行了类似评估。分析显示，ITBL 组和非 ITBL 组在时间 0 时的组织学差异无统计学意义。然而，与非 ITBL 组相比，ITBL 组的时间 1 活检样本中较小的门静脉分支（PVB）更常见，而非 ITBL 组中也存在持续的门旁侧支血管。CRC 组中也发现了较大的 PVB 和门旁侧支血管。形态计量学分析证实了这些发现，并表明与 ITBL 组的时间 0 活检样本相比，ITBL 组在时间 1 的 PVB 测量值显著降低，与非 ITBL 组和 CRC 组相比也显著降低（在 CRC 组中最大）。因此，与时间 0 活检样本相比，ITBL 组的 PVB 尺寸在再灌注后活检样本中减小，并且与非 ITBL 组和 CRC 组的尺寸相比，在时间 1 时明显更小。总之，在肝移植后再灌注活检样本中，PVB 管腔尺寸较小，提示门静脉血流相对减少，与 ITBL 的发生率较高相关。这些发现支持最近的临床研究，表明门静脉血流在 LT 后胆道氧合中的可能具有病理生理作用。
