A comparison of islet autotransplantation with allotransplantation and factors elevating acute portal pressure in clinical islet transplantation.

BACKGROUND: Acute portal pressure rise is occasionally observed during intraportal islet infusion, especially in islet autotransplantation (IAT) where tissue purification is rarely applied. In this paper we investigate factors associated with acute portal pressure rise, a known risk factor for portal vein thrombosis.
METHODS: Retrospective data was collected on 15 islet autotransplant and 122 allogeneic islet transplant subjects. Non-purified pancreatic cells were transplanted in islet autotransplants, and purified islet cells were transplanted in allogeneic transplants. Portal pressure was documented throughout the islet infusion.
RESULTS: The total numbers of transplanted islets were significantly smaller in autotransplants than allografts, although the packed cell volume in autotransplants was larger. Autoislet infusion, with a larger packed cell volume, caused higher transient portal venous pressures than allogeneic islet transplant. Univariate analysis and multivariate linear regression revealed that packed cell volume and the number of transplanted cells were significant risk factors for acute portal pressure rise in both autotransplants and allogeneic transplants.
CONCLUSIONS: Non-purified IAT has a higher risk for acute portal pressure rise than allogeneic islet transplantation, and the rise is associated with the packed cell volume and the number of transplanted cells. Minimization of packed cell volume and cautious monitoring of portal pressure are important to avoid potential complications of portal hypertension.