Residual ß-cell function and insulin sensitivity following intestinal transplantation: a single center perspective.

Background: Blood chimerism is the coexistence of donor and recipient hematopoietic cells.This study examines chimerism levels and clinical manifestations in pediatric multivisceral transplant recipients, focusing on graft-versus-host disease (GVHD).Methods: Retrospective descriptive observational study of all patients who received a multivisceral transplant since 2020 in our center.Demographic data, transplant type, pre-transplant induction therapy, peripheral blood chimerism levels (CD3+, CD3/CD19-) during the first two years post-transplant, and the occurrence of graft-versus-host disease (GVHD) are described.Results: Fifteen patients (2/15 women) were registered over five years, with a median age of 42 months.Thirty-three percent (5/15) of the patients developed GVHD (cutaneous/gastrointestinal/pulmonary/hematologic) within the first two years posttransplant.At disease onset, 80% (4/5) of these patients exhibited an increase in peripheral blood chimerism levels above 20%, with a mean peak value of 34.1%.Among patients who did not develop GVHD, none reached chimerism levels above 20%, with a mean peak value of 8.8%.Patients who received alemtuzumab (4/15) as induction therapy had a mean peak chimerism level of 3.5%, and none of them developed GVHD.Conclusions: Peripheral blood chimerism levels may be associated with the immunological origin of complications following intestinal transplantation, such as graft-versus-host disease.Additionally, alemtuzumab may play a role in preventing GVHD in multivisceral transplantation.However, further studies with larger patient cohorts are needed to establish these relationships.