Background: Stability of graft function after allotransplantation is difficult to maintain. There are many factors that can worsen recipient's condition and may lead to acute graft rejection. The aim of this study was to evaluate the influence of various factors on the incidence of acute graft rejection episodes in patients after liver and kidney allotransplantation.
Material/Methods: 171 recipients after kidney and liver transplantation were
analyzed. Factors of interest included: immunosuppression patterns, existence of diabetes, received induction therapy, warm and cold ischemia time and acute rejection time. Next, the data of donors for the 171 patients was collected. All data was statistically analyzed.
Results: The number of kidney and liver recipients without acute graft rejection was the lowest for CsA and CellCept model compared to the highest for CsA and Aza model (p=0.0008). Tacrolimus causes the highest risk of induced diabetes after transplantation (p<0.001). The number of kidney and liver recipients with acute graft rejection was higher in patients who received graft from females comparing with the group who received grafts from males (p=0.0282). Every minute of warm ischemia time increases the risk of acute
graft rejection by 12.7%. The percentage of patients without AGR after 7 months with 2 common alleles, 1 common allele and 0 common alleles in HLA-DR was 100%, 55% and 30% respectively (p=0.0128).
Conclusions: The acute rejection time depends on many factors and how they affect graft stability was elucidated in this study.

Keywords: Immunosuppression, Kidney Transplantation, Liver Transplantation