Repeat A2 Into B Kidney Transplantation After Failed Prior A2 Into B Transplant: A Case Report
Kidneys from donors with blood type A2 can be successfully transplanted into blood type B and O recipients without the need for desensitization if the recipient's starting anti-A hemagglutinin titer is within an acceptable range. National kidney allocation policy now offers priority for eligible B recipients to receive A2 or A2B deceased donor kidneys, and therefore, the frequency with which A2 or A2B to B transplants will occur is expected to increase. The precise mechanisms by which antibody-mediated rejection is averted in these cases despite the presence of both circulating anti-A antibody and expression of the A2 antigen on the graft endothelium are not known. Whether this process mirrors proposed mechanisms of accommodation, which can occur in recipients of ABO incompatible transplants, is also not known. Repeated exposure to mismatched antigens after retransplantation could elicit memory responses resulting in antibody rebound and accelerated antibody-mediated rejection. Whether this would occur in the setting of repeated A2 donor exposure was uncertain. Here we report the case of a patient with history of a prior A2 to B transplant which failed owing to nonimmunologic reasons; the patient successfully underwent a repeat A2 to B transplant. Neither rebound in anti-A2 antibody nor clinical evidence of antibody-mediated rejection were observed after the transplant. Current kidney allocation will likely enable more such transplants in the future, and this may provide a unique patient population in whom the molecular mechanisms of incompatible graft accommodation may be investigated.
Nuclear Factor of Activated T Cell-regulated Cytokine Gene Expression for Adjustment of Tacrolimus in Kidney Transplant Recipients: A Randomized Controlled Pilot Trial
Background/UNASSIGNED:The aim of this pilot study was to assess the feasibility of a pharmacodynamics assay that measures Nuclear Factor of Activated T Cell-dependent cytokines expressed as % mean residual expression (MRE) to adjust tacrolimus (tac) dose (intervention [INT] arm) in comparison with the standard of care of tac trough levels (control [CTL] arm). Methods/UNASSIGNED:We conducted a single-center randomized controlled trial involving 40 stable kidney transplant recipients over 1 year. In the INT arm, the dose of tac was reduced by 15% if the MRE was less than 20% and was increased by 15% if the MRE was greater than 60%. Controls were adjusted based on tac trough levels. Results/UNASSIGNED:= 0.80). There was no correlation between MRE and rejection. Conclusions/UNASSIGNED:Our study suggests that adjusting tac based on this pharmacodynamics assay is feasible. Quantitative analysis of nuclear factor of activated T-regulated gene expression may serve as a reliable assay to lower tac dosing. Further studies with larger populations are needed.
Fosfomycin vs Other Antibiotics for UTI after Kidney Transplant. [Meeting Abstract]
Early Graft Function Correlates with Survival Benefit in Kidney Transplant Recipients with Peripheral Vascular Disease. [Meeting Abstract]
IgG Degrading Enzyme of Streptococcus Pyogenes: An Exciting New Development in Desensitization Therapy
Early Conversion from Tacrolimus to Belatacept in a Highly Sensitized Renal Allograft Recipient with Calcineurin Inhibitor-Induced de novo Post-Transplant Hemolytic Uremic Syndrome
Background/UNASSIGNED:Kidney transplantation is the first-line therapy for patients with end-stage renal disease since it offers greater long-term survival and improved quality of life when compared to dialysis. The advent of calcineurin inhibitor (CNI)-based maintenance immunosuppression has led to a clinically significant decline in the rate of acute rejection and better short-term graft survival rates. However, these gains have not translated into improvement in long-term graft survival. CNI-related nephrotoxicity and metabolic side effects are thought to be partly responsible for this. Case Presentation/UNASSIGNED:Here, we report the conversion of a highly sensitized renal transplant recipient with pretransplant donor-specific antibodies from tacrolimus to belatacept within 1 week of transplantation. This substitution was necessitated by the diagnosis of CNI-induced de novo post-transplant hemolytic uremic syndrome. Conclusion/UNASSIGNED:Belatacept is a novel costimulation blocker that is devoid of the nephrotoxic properties of CNIs and has been shown to positively impact long-term graft survival and preserve renal allograft function in low-immunologic-risk kidney transplant recipients. Data regarding its use in patients who are broadly sensitized to human leukocyte antigens are scarce, and the increased risk of rejection associated with belatacept has been a deterrent to more widespread use of this immunosuppressive agent. This case serves as an example of a highly sensitized patient that has been successfully converted to a belatacept-based CNI-free regimen.
APOL1 genotyping in potential kidney donors of African descent [Meeting Abstract]
Background: Inheritance of two APOL1 risk variants accounts for the excess risk of non-diabetic ESRD in African Americans when compared to Caucasian, Hispanic and Asian Americans. African American living donors have a higher risk of ESRD than matched non-black donors. APOL1 genotyping in potential kidney donors of African descent may identify individuals at risk for progressive CKD following donation.
Method(s): We report the retrospective analysis of APOL1 genotyping in a cohort of African American potential kidney donors. In July 2016, we initiated targeted genotyping of all African American kidney donor candidates. African American candidates with two APOL1 risk variants were excluded from kidney donation.
Result(s): A total of 28 African American kidney donor candidates were evaluated between July 2016 and April 2018. 2 (7%) were found to have two APOL1 risk variants (high risk genotype). Low risk genotype was identified in 10 (36%) candidates who had one risk variant and 16 (57%) candidates who had none. To date, 15 candidates have completed their donor work-up. Of these, 7 (47%) have already undergone donor nephrectomy, and 4 (27%) were cleared for surgery and are awaiting operation. 4 (27%) of the candidates did not meet our center specific criteria for donation. 2 out these 4 candidates who were excluded from donation were ruled out expressly for having been found to have two APOL1 risk variants.
Conclusion(s): APOL1 genotyping led to the exclusion of two donors who might have previously been allowed to donate, possibly mitigating their risk of CKD/ESRD and suboptimal graft outcomes in recipients. (Table Presented)
NFAT-Regulated Cytokine Gene Expression for Immune Monitoring in Kidney Transplant Recipients-A Randomized Controlled Trial [Meeting Abstract]
Pharmacologic Complement Inhibition in Clinical Transplantation
Purpose of Review/UNASSIGNED:Over the past two decades, significant strides made in our understanding of the etiology of antibody-mediated rejection (AMR) in transplantation have put the complement system in the spotlight. Here, we review recent progress made in the field of pharmacologic complement inhibition in clinical transplantation and aim to understand the impact of this therapeutic approach on outcomes in transplant recipients. Recent Findings/UNASSIGNED:Encouraged by the success of agents targeting the complement cascade in disorders of unrestrained complement activation like paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic uremic syndrome (aHUS), investigators are testing the safety and efficacy of pharmacologic complement blockade in mitigating allograft injury in conditions ranging from AMR to recurrent post-transplant aHUS, C3 glomerulopathies and antiphospholipid anti-body syndrome (APS). A recent prospective study demonstrated the efficacy of terminal complement inhibition with eculizumab in the prevention of acute AMR in human leukocyte antigen (HLA)-incompatible living donor renal transplant recipients. C1 esterase inhibitor (C1-INH) was well tolerated in two recent studies in the treatment of AMR and was associated with improved renal allograft function. Summary/UNASSIGNED:Pharmacologic complement inhibition is emerging as valuable therapeutic tool, especially in the management of highly sensitized renal transplant recipients. Novel and promising agents that target various elements in the complement cascade are in development. Graphical Abstractá…Ÿ.
Factors Associated with Response to Plasmapheresis in Patients with Recurrent FSGS. [Meeting Abstract]