OPTN/SRTR 2019 Annual Data Report: Pancreas.

The overall number of pancreas transplants decreased slightly, from 1027 in 2018 to 1015, in 2019, up from a nadir of 947 in 2015. However, the number of simultaneous pancreas-kidney transplants (SPKs) increased in 2019, with a corresponding drop in pancreas-after-kidney transplants (PAKs) and pancreas transplants alone (PTAs). New waitlist registrations increased to 1772 in 2019, from 1606 in 2018. This was predominately driven by SPK listings, and those with type 2 diabetes. Waiting time for SPK decreased by 2 months, to a median of 12 months in 2019, but PTA recipient mean waiting time remained substantially higher, at 24 months, in 2018. Both short- and long-term outcomes, including patient survival, kidney graft survival, and acute rejection-free graft survival, have shown consistent improvement over the last decade. Pancreas graft survival data with the uniform definition of allograft failure is being collected by the Organ Procurement and Transplant Network (OPTN) and will be included in a future report.

Acute cellular and antibody-mediated rejection of the pancreas allograft: incidence, risk factors and outcomes.

Antibody-mediated rejection (AMR) after pancreas transplantation is a recently identified entity. We describe the incidence of, risk factors for, and outcomes after AMR, and the correlation of C4d immunostaining and donor-specific antibody (DSA) in the diagnosis of AMR. We retrospectively analyzed 162 pancreas transplants in 159 patients who underwent 94 pancreas allograft biopsies between 2006 and 2009. Univariate and multivariate analyses were performed to evaluate risk factors for pancreas graft AMR. One-year rejection rates and survival after rejection were calculated by Kaplan-Meier methods. AMR occurred in 10% of patients by 1-year posttransplant. Multivariate risk factors identified for AMR include nonprimary simultaneous pancreas-kidney (SPK) transplant, primary solitary pancreas (PAN) transplant and race mismatch. After pancreas rejection, patient survival was 100% but 20% (8 of 41) of pancreas grafts failed within 1 year. Graft survival after acute cellular rejection (ACR), AMR and mixed rejection was similar. Of biopsies that stained >5% C4d, 80% were associated with increased Class I DSA. In summary, AMR occurs at a measurable rate after pancreas transplantation, and the diagnosis should be actively sought using C4d staining and DSA levels in patients with graft dysfunction, especially after nonprimary SPK and primary PAN transplantation.