Background: Graft endothelium constitutes a prime target during acute rejection. Infiltration of T cells, monocytes, and enhanced endothelial-leukocyte interactions result in microvascular impairment and altered perfusion.
Materials and methods: We measured mucosal blood flow using a laser Doppler flowmeter in three patients undergoing multivisceral transplantation. Thirty-seven measurements were performed through the ileostomy over the first 4 weeks posttransplantation. Most measurements were performed within a 24-hour interval from endoscopy and biopsy.
Results: Mucosal perfusion increased throughout the first postoperative week and eventually stabilized around levels specific for each patient. Mucosal perfusion remained stable during graft pancreatitis, but decreased 35% to 55% from baseline (the average value of the previous measurements) during acute rejection and sepsis. During the first week posttransplantation there was a gradual increase in mucosal perfusion, which might reflect regeneration after reperfusion injury. Increased mucosal perfusion did not seem to correlate with rejection or other adverse clinical events. A sudden decrease in mucosal perfusion of 30% or more compared to the previous measurements was associated with septic episodes and/or rejection.