Desensitisation strategies in high-risk children before kidney transplantation

Overcoming limits: First ABO incompatible living donor paired kidney transplant in an hypersensitized pediatric recipient in Spain

INTRODUCTION

HLA sensitization is a growing problem in children awaiting kidney transplantation. In some cases, finding an immunologically compatible donor entails contemplating the option of an ABO incompatible transplant or paired transplant.

METHODS

Patient with genetic nephrotic syndrome and progressive chronic kidney disease, with a previous thrombosis of a first kidney transplant, resulting hypersensitized and remaining for a long-time on hemodialysis. Despite a desensitization strategy, family members were incompatible and deceased donation options must be ruled out due to the presentation of donor-specific antibodies (DSA). After 4 years, the possibility arises to perform a kidney paired transplant with a 62-year-old woman with an incompatible blood group. Although the current cytotoxicity- and cell-based crossmatches were negative, history of DSA were recorded.

RESULTS

An intensive ABO and HLA desensitization protocol was performed in order to combat the isohemagglutinin antibodies and on the memory-HLA, based on rituximab, apheresis sessions, and immunoglobulins. Despite the donor being older in terms of pediatric transplantation, the donor-recipient weight difference, and immunological risk, the transplant was completed successfully. Maintenance of titration of up to 1/2 was confirmed after 3 weeks post-transplant (IgM and IgG). Kidney biopsy at 2 weeks and 6 months without signs of rejection. The patient is currently 12 months post-transplant and has not presented any signs of transplant rejection and has proper renal function.

CONCLUSIONS

Kidney paired transplantation is an excellent solution for hypersensitized children, and ABO incompatibility can be considered to increase their options to find a good donor, without thereby obtaining worse results.

Recommendations for living donor kidney transplantation

This Guide for Living Donor Kidney Transplantation (LDKT) has been prepared with the sponsorship of the Spanish Society of Nephrology (SEN), the Spanish Transplant Society (SET), and the Spanish National Transplant Organization (ONT). It updates evidence to offer the best chronic renal failure treatment when a potential living donor is available. The core aim of this Guide is to supply clinicians who evaluate living donors and transplant recipients with the best decision-making tools, to optimise their outcomes. Moreover, the role of living donors in the current KT context should recover the level of importance it had until recently. To this end the new forms of incompatible HLA and/or ABO donation, as well as the paired donation which is possible in several hospitals with experience in LDKT, offer additional ways to treat renal patients with an incompatible donor. Good results in terms of patient and graft survival have expanded the range of circumstances under which living renal donors are accepted. Older donors are now accepted, as are others with factors that affect the decision, such as a borderline clinical history or alterations, which when evaluated may lead to an additional number of transplantations. This Guide does not forget that LDKT may lead to risk for the donor. Pre-donation evaluation has to centre on the problems which may arise over the short or long-term, and these have to be described to the potential donor so that they are able take them into account. Experience over recent years has led to progress in risk analysis, to protect donors' health. This aspect always has to be taken into account by LDKT programmes when evaluating potential donors. Finally, this Guide has been designed to aid decision-making, with recommendations and suggestions when uncertainties arise in pre-donation studies. Its overarching aim is to ensure that informed consent is based on high quality studies and information supplied to donors and recipients, offering the strongest possible guarantees.

Antibody-mediated rejection after kidney transplantation in children; therapy challenges and future potential treatments

Antibody‐mediated rejection (AMR) remains one of the most critical problems in renal transplantation, with a significant impact on patient and graft survival. In the United States, no treatment has received FDA approval jet. Studies about treatments of AMR remain controversial, limited by the absence of a gold standard and the difficulty in creating large, multi‐center studies. These limitations emerge even more in pediatric transplantation because of the limited number of pediatric studies and the occasional use of some therapies with unknown and poorly documented side effects. The lack of recommendations and the unsharp definition of different forms of AMR contribute to the challenging management of the therapy by pediatric nephrologists. In an attempt to help clinicians involved in the care of renal transplanted children affected by an AMR, we rely on the latest recommendations of the Transplantation Society (TTS) for the classification and treatment of AMR to describe treatments available today and potential new treatments with a particular focus on the pediatric population.

Role of therapeutic apheresis in the treatment of pediatric kidney diseases

Therapeutic apheresis utilizes apheresis procedures in the treatment of a variety of conditions including kidney disease. Therapeutic plasma exchange (TPE) is the most common modality employed with the rationale of rapid reduction of a pathogenic substance distributed primarily in the intravascular compartment; however other techniques which adsorb such pathogenic substances or alter the immune profile have been utilized in diseases affecting native and transplanted kidneys. This article discusses the modalities and technical details of therapeutic apheresis and summarizes its role in individual diseases affecting the kidney. Complications related to pediatric apheresis procedures and specifically related to apheresis in kidney disease are also discussed. Though therapeutic apheresis modalities are employed frequently in children with kidney disease, most experiences are extrapolated from adult studies. International and national registries need to be established to elucidate the role of apheresis modalities in children with kidney disease.