Analysis of acute and chronic rejection in multiple organ allografts from retransplantation and autopsy cases of multivisceral transplantation

Background. Small intestinal allografts in multivisceral transplantation are felt to be more susceptible to acute cellular rejection (ACR) and chronic rejection (CR) when compared with other allografts although there is little direct evidence for this impression. Methods. A total of 48 cases of multiple allograft specimens (3 7 autopsy and 11 explanted allograft cases) from 41 patients were evaluated in this study. Histopathologic assessments were performed with special concern to ACR and CR in allografts. The numbers of allografts available for evaluation were liver 37, small intestine 47, stomach 41, pancreas 45, and large intestine 25. Results. Among 48 cases, 15 cases showed ACR (ACR case) and 12 showed CR (CR case) in at least one organ. In ACR cases, there was a statistically significant difference of organ-specific susceptibility to ACR among multivisceral allografts with the small intestinal allograft being the most susceptible (P < 0.05). Severe ACR were observed only in small and large intestinal allografts. In CR cases, there was no statistically significant difference of organ-specific susceptibility to CR among multivisceral allografts with a tendency for the pancreas allograft to be the most susceptible (P = 0.35). Conclusions. Our study clearly indicated variation in organ susceptibility to ACR and CR. Small intestinal allografts were the most susceptible organ to ACR in frequency and severity. Pancreatic allografts maybe more susceptible to CR in comparison with ACR.