Outcomes of Severity-Stratified Antithrombotic Management of Imaging-Detected Thrombosis After Simultaneous Pancreas-Kidney Transplantation

BackgroundPancreas allograft thrombosis is an important cause of early graft dysfunction and loss after simultaneous pancreas-kidney (SPK) transplantation, and postoperative antithrombotic practices vary among centers.We describe outcomes of an institutional severity-stratified antithrombotic approach in which treatment intensity was linked to imaging-defined thrombus burden. Materials and methodsWe performed a single-center, single-arm, descriptive, retrospective cohort study of 79 adult SPK recipients who were transplanted between January 1, 2018, and September 17, 2025.Postoperative Doppler ultrasound and, when indicated, computed tomography angiography were used to identify vascular abnormalities.Management generally consisted of aspirin for normal vascular findings, clopidogrel for limited venous thrombus involving <50% of the vessel, and systemic anticoagulation for more extensive, progressive, or arterial thrombosis.Outcomes included thrombosis, study-defined major bleeding, thrombosis-attributed pancreas graft loss, and one-year patient and graft survival.Rotational thromboelastometry EXTEM was evaluated exploratorily when available. ResultsVenous thrombosis occurred in 18 of 79 recipients (22.8%), including 10 with <50% involvement and eight with ≥50% involvement.Arterial thrombosis occurred in one patient (1.3%).Clinically significant thrombosis, which included persistent or progressive venous thrombus on repeat imaging, occurred in 14 patients (17.7%), while thrombosis-attributed pancreas graft loss occurred in three (3.8%).Study-defined major bleeding occurred in seven patients (8.9%).Among 76 recipients with at least one year of potential follow-up, one-year patient, kidney graft, and pancreas graft survival rates were 92.1%, 89.5%, and 81.6%, respectively (death was counted as graft loss).A classifiable EXTEM profile was available in 57 patients (72.2%), with no consistent association between coagulation profile and thrombosis or study-defined major bleeding. ConclusionsSeverity-stratified antithrombotic management based on imaging-defined thrombus burden was implemented in this cohort, and thrombosis-attributed pancreas graft loss occurred in three of 79 patients (3.8%).However, the retrospective design, small numbers of events, absence of a contemporaneous comparator, and possible variation in institutional practice preclude a conclusion regarding comparative effectiveness or safety.Prospective studies using standardized imaging and treatment criteria are warranted.