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Aims: Tacrolimus, metabolized by CYP3A4 and CYP3A5 enzymes, is susceptible to drug–drug interactions (DDI). Steroids induce CYP3A genes to increase tacrolimus clearance, but the effect is variable. We hypothesized that the extent of the steroid–tacrolimus DDI differs by CYP3A4/5 genotypes. Methods: Kidney transplant recipients (n = 2462) were classified by the number of loss of function alleles (LOF) (CYP3A5*3, *6 and *7 and CYP3A4*22) and steroid use at each tacrolimus trough in the first 6 months post‐transplant. A population pharmacokinetic analysis was performed by nonlinear mixed‐effect modelling (NONMEM) and stepwise covariate modelling to define significant covariates affecting tacrolimus clearance. A stochastic simulation was performed and translated into a Shiny application with the mrgsolve and Shiny packages in R. Results: Steroids were associated with modestly higher (3%–11.8%) tacrolimus clearance. Patients with 0‐LOF alleles receiving steroids showed the greatest increase (11.8%) in clearance compared to no steroids, whereas those with 2‐LOFs had a negligible increase (2.6%) in the presence of steroids. Steroid use increased tacrolimus clearance by 5% and 10.3% in patients with 1‐LOF and 3/4‐LOFs, respectively. Conclusions: Steroids increase the clearance of tacrolimus but vary slightly by CYP3A genotype. This is important in individuals of African ancestry who are more likely to carry no LOF alleles, may more commonly receive steroid treatment, and will need higher tacrolimus doses. [ABSTRACT FROM AUTHOR]

Living donor kidney transplantation (LDKT) offers better quality of life and clinical outcomes, including patient survival, compared with remaining on dialysis or receiving a deceased donor kidney transplant. Although LDKT education within transplant centers for both potential recipients and living donors is very important, outreach and education to kidney patients in settings other than transplant centers and to the general public is also critical to increase access to this highly beneficial treatment. In June 2014, the American Society of Transplantation's Live Donor Community of Practice, with the support of 10 additional sponsors, convened a consensus conference to determine best practices in LDKT, including a workgroup focused on developing a set of recommendations for optimizing outreach and LDKT education outside of transplant centers. Members of this workgroup performed a structured literature review, conducted teleconference meetings, and met in person at the 2-day conference. Their efforts resulted in consensus around the following recommendations. First, preemptive transplantation should be promoted through increased LDKT education by primary care physicians and community nephrologists. Second, dialysis providers should be trained to educate their own patients about LDKT and deceased donor kidney transplantation. Third, partnerships between community organizations, organ procurement organizations, religious organizations, and transplant centers should be fostered to support transplantation. Fourth, use of technology should be improved or expanded to better educate kidney patients and their support networks. Fifth, LDKT education and outreach should be improved for kidney patients in rural areas. Finally, a consensus-driven, evidence-based public message about LDKT should be developed. Discussion of the effect and potential for implementation around each recommendation is featured, particularly regarding reducing racial and socioeconomic disparities in access to LDKT. To accomplish these recommendations, the entire community of professionals and organizations serving kidney patients must work collaboratively toward ensuring accurate, comprehensive, and up-to-date LDKT education for all patients, thereby reducing barriers to LDKT access and increasing LDKT rates.

Background: Chronic immunosuppression following pancreas transplantation carries significant risk, including posttransplant lymphoproliferative disease (PTLD). We sought to define the incidence, risk factors, and long‐term outcomes of PTLD following pancreas transplantation at a single center. Methods: All adult pancreas transplants between February 1, 1983 and December 31, 2023 at the University of Minnesota were reviewed, including pancreas transplant alone (PTA), simultaneous pancreas–kidney transplants (SPK), and pancreas after kidney transplants (PAK). Results: Among 2353 transplants, 110 cases of PTLD were identified, with an overall incidence of 4.8%. 17.3% were diagnosed within 1 year of transplant, 32.7% were diagnosed within 5 years, and 74 (67.3%) were diagnosed after 5 years. The overall 30‐year incidence of PTLD did not differ by transplant type—7.4% for PTA, 14.2% for SPK, and 19.4% for PAK (p = 0.3). In multivariable analyses, older age and Epstein‐Barr virus seronegativity were risk factors for PTLD, and PTLD was a risk factor for patient death. PTLD‐specific mortality was 32.7%, although recipients with PTLD had similar median posttransplant survival compared to those without PTLD (14.9 year vs. 15.6 year, p = 0.9). Conclusions: PTLD following pancreas transplantation is associated with significant mortality. Although the incidence of PTLD has decreased over time, a high index of suspicion for PTLD following PTx should remain in EBV‐negative recipients. [ABSTRACT FROM AUTHOR]

Background: Acute rejection (AR) after kidney transplantation is an important allograft complication. To reduce the risk of post-transplant AR, determination of kidney transplant donor-recipient mismatching focuses on blood type and human leukocyte antigens (HLA), while it remains unclear whether non-HLA genetic mismatching is related to post-transplant complications. Methods: We carried out a genome-wide scan (HLA and non-HLA regions) on AR with a large kidney transplant cohort of 784 living donor-recipient pairs of European ancestry. An AR polygenic risk score (PRS) was constructed with the non-HLA single nucleotide polymorphisms (SNPs) filtered by independence (r2 < 0.2) and P-value (< 1×10−3) criteria. The PRS was validated in an independent cohort of 352 living donor-recipient pairs. Results: By the genome-wide scan, we identified one significant SNP rs6749137 with HR = 2.49 and P-value = 2.15×10−8. 1,307 non-HLA PRS SNPs passed the clumping plus thresholding and the PRS exhibited significant association with the AR in the validation cohort (HR = 1.54, 95% CI = (1.07, 2.22), p = 0.019). Further pathway analysis attributed the PRS genes into 13 categories, and the over-representation test identified 42 significant biological processes, the most significant of which is the cell morphogenesis (GO:0000902), with 4.08 fold of the percentage from homo species reference and FDR-adjusted P-value = 8.6×10−4. Conclusions: Our results show the importance of donor-recipient mismatching in non-HLA regions. Additional work will be needed to understand the role of SNPs included in the PRS and to further improve donor-recipient genetic matching algorithms. Trial registry: Deterioration of Kidney Allograft Function Genomics (NCT00270712) and Genomics of Kidney Transplantation (NCT01714440) are registered on ClinicalTrials.gov. [ABSTRACT FROM AUTHOR]

Virtually all clinicians agree that living donor renal transplantation is the optimal treatment for permanent loss of kidney function. Yet, living donor kidney transplantation has not grown in the United States for more than 2 decades. A virtual symposium gathered experts to examine this shortcoming and to stimulate and clarify issues salient to improving living donation. The ethical principles of rewarding kidney donors and the limits of altruism as the exclusive compelling stimulus for donation were emphasized. Concepts that donor incentives could save up to 40 000 lives annually and considerable taxpayer dollars were examined, and survey data confirmed voter support for donor compensation. Objections to rewarding donors were also presented. Living donor kidney exchanges and limited numbers of deceased donor kidneys were reviewed. Discussants found consensus that attempts to increase living donation should include removing artificial barriers in donor evaluation, expansion of living donor chains, affirming the safety of live kidney donation, and assurance that donors incur no expense. If the current legal and practice standards persist, living kidney donation will fail to achieve its true potential to save lives. [ABSTRACT FROM AUTHOR]