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Incompatible living donor kidney transplant recipients (ILDKTr) have pre-existing donor-specific antibody (DSA) that, despite desensitization, may persist or reappear with resulting consequences, including delayed graft function (DGF) and acute rejection (AR). To quantify the risk of DGF and AR in ILDKT and downstream effects, we compared 1406 ILDKTr to 17 542 compatible LDKT recipients (CLDKTr) using a 25-center cohort with novel SRTR linkage. We characterized DSA strength as positive Luminex, negative flow crossmatch (PLNF); positive flow, negative cytotoxic crossmatch (PFNC); or positive cytotoxic crossmatch (PCC). DGF occurred in 3.1% of CLDKT, 3.5% of PLNF, 5.7% of PFNC, and 7.6% of PCC recipients, which translated to higher DGF for PCC recipients (aOR = 1.03 1.682.72 ). However, the impact of DGF on mortality and DCGF risk was no higher for ILDKT than CLDKT (p interaction > .1). AR developed in 8.4% of CLDKT, 18.2% of PLNF, 21.3% of PFNC, and 21.7% of PCC recipients, which translated to higher AR (aOR PLNF = 1.45 2.093.02 ; PFNC = 1.67 2.403.46 ; PCC = 1.48 2.243.37 ). Although the impact of AR on mortality was no higher for ILDKT than CLDKT (p interaction = .1), its impact on DCGF risk was less consequential for ILDKT (aHR = 1.34 1.621.95 ) than CLDKT (aHR = 1.96 2.292.67 ) (p interaction = .004). Providers should consider these risks during preoperative counseling, and strategies to mitigate them should be considered.

Patients with significant medical comorbidities such as chronic kidney disease (CKD) traditionally have been excluded from hematopoietic stem cell transplantation (HSCT) because of unacceptably high transplant-related morbidity and mortality, an exclusion that can have enormous consequences for patients with CKD from myeloma in particular. Much of the excess HSCT-related morbidity among CKD patients relates to the toxic effects of conditioning regimens, which have a narrow therapeutic index even in patients with normal renal function. Common posttransplant complications are more challenging to prevent and manage in patients with CKD. In selected centers, autologous HSCT is performed with some frequency in patients with advanced CKD and even dialysis-dependent end-stage renal disease (ESRD), with acceptable outcomes, but cure from malignancy rarely is obtained. Allogeneic transplants using reduced-intensity conditioning regimens are being used with increasing frequency in patients with CKD, for both nonmalignant and malignant conditions, relying in the latter case on a graft-versus-malignancy effect to eliminate residual malignancy. In patients with ESRD from myeloma who have suitable donors, simultaneous allogeneic HSCT and kidney transplantation from a human leukocyte antigen-identical sibling provides the opportunity to treat both the malignant condition and the ESRD, avoiding the risks of posttransplant care in a dialysis-dependent patient and freeing the patient of the subsequent burdens of both ongoing dialysis and immunosuppression.

Aim Beginning on March 25, 2015, our institution’s kidney transplant program has implemented a “readiness” protocol, whereby patients are listed after limited workup and comprehensive testing is deferred until the anticipated time to transplantation is approximately 6–12 months. Prior to implementation of this protocol, our histocompatibility laboratory would receive monthly sera for anti-HLA antibody screening immediately upon listing. However, as part of the readiness strategy, the lab now requests monthly samples only when a candidate is predicted to have 6–12 months of waitlist time remaining. The monthly samples are stored and screened in the lab per protocol (every 3 months for most patients). All candidates are also screened once prior to listing and again immediately after listing. Methods Data from our laboratory database and UNOS were analyzed to determine the number of samples received from waitlisted kidney transplant candidates and the number tested in the three-year period before and after implementation of the readiness protocol. Results Our kidney transplant waitlist has grown from 379 candidates on 7/1/2012 to 948 as of 4/5/2018. Despite this rapid growth, the number of samples received from kidney transplant candidates has decreased from 9171 during the three-year period prior to the implementation of readiness (∼3057/year) to 7924 during the subsequent three-year period (∼2641/year). Based on a sample submission rate of ∼7 samples/patient/year, an estimated 4961 samples per year would have been received without the readiness protocol, with an estimated 6669 samples expected for 2018. From 3/25/12–3/24/15, 4730 antibody screening tests on kidney waitlist candidates were performed by Luminex (∼1577 tests/year), compared to a slight increase to 5082 from 3/25/15–3/24/18 (∼1694 tests/year), despite a 2.5-fold increase in patients on the waitlist from 2012–2018. Conclusions Implementation of the readiness protocol has streamlined the pre-transplant testing process and reduced both the number of samples received and the number tested. This has allowed us to manage a greatly increased waitlist with the same level of resources and has resulted in reduced cost per patient.