Kidney transplant outcomes associated with the use of increased risk donors in children

A modified Kidney Donor Risk Index for pediatric kidney transplant recipients

BACKGROUND

The Kidney Donor Risk Index (KDRI) by Rao et al. was developed to measure the quality of kidney allografts. While Rao's KDRI has been found to be a robust measure of kidney allograft survival for adult kidney transplant recipients, many studies have indicated the need to create a distinct pediatric KDRI.

METHODS

Our retrospective study utilized data from the United Network for Organ Sharing database. We examined 9295 deceased donor recipients' data for age < 18 years from 1990 to 2020. We performed a multivariate Cox regression to determine the significant recipient and transplant factors impacting pediatric kidney allograft survival.

RESULTS

Multivariate analysis found 5 donor factors to be independently associated with graft failure or recipient death: age, female sex, anoxia as the cause of death, history of cigarette use, and cold ischemia time. Using receiver operator characteristic (ROC) curve analysis and analyzing the predictive value of each KDRI at 1, 5, and 10 years, the proposed pediatric KDRI had a statistically significant and higher predictive value for pediatric recipients at 5 (0.60 versus 0.57) and 10 years (0.61 versus 0.57) than the Rao KDRI.

CONCLUSIONS

The proposed pediatric KDRI may provide a more accurate and simpler index to assess the quality of kidney allografts for pediatric recipients. However, due to the mild increase in predictive capabilities over the Rao index, the study serves as a proof of concept to develop a pediatric KDRI. Further studies should focus on increasing the index's predictive capabilities. A higher resolution version of the Graphical abstract is available as Supplementary information.

Inequities in organ and tissue donation and transplantation for sexual orientation and gender identity diverse people: A scoping review

Sexual orientation and gender identity (SOGI) diverse populations experience discrimination in organ and tissue donation and transplantation (OTDT) systems globally. We assembled a multidisciplinary group of clinical experts as well as SOGI-diverse patient and public partners and conducted a scoping review including citations on the experiences of SOGI-diverse persons in OTDT systems globally to identify and explore the inequities that exist with regards to living and deceased OTDT. Using scoping review methods, we conducted a systematic literature search of relevant electronic databases from 1970-2021 including a grey literature search. We identified and screened 2402 references and included 87 unique publications. Two researchers independently coded data in included publications in duplicate. We conducted a best-fit framework synthesis paired with an inductive thematic analysis to identify synthesized benefits, harms, inequities, justification of inequities, recommendations to mitigate inequities, laws and regulations, as well as knowledge and implementation gaps regarding SOGI-diverse identities in OTDT systems. We identified numerous harms and inequities for SOGI-diverse populations in OTDT systems. There were no published benefits of SOGI-diverse identities in OTDT systems. We summarized recommendations for the promotion of equity for SOGI-diverse populations and identified gaps that can serve as targets for action moving forward.

Use of organs from increased infectious risk deceased donors in pediatric kidney transplantation

Living donors are the main source of transplanted kidneys for children and young people in many countries, but there still remains a significant need for deceased donor kidney transplantation. Given the waiting times associated with deceased donor kidney transplantation and the morbidity or mortality that can occur in those on the waiting list, it is essential that the utilization of kidneys from deceased donors is optimized. The use of organs from deceased donors at increased risk of transmitting human immunodeficiency virus, hepatitis B virus, or hepatitis C virus is relatively common in adults, but far less so in children. The risks and benefits of the use of kidneys from increased infectious risk donors (IIRD) are discussed. The variation of definitions of IIRD between countries is explored as is the need for pediatric nephrologists and transplant surgeons to have an understanding of the prevalence of viral diseases within the country in which they work. The role of screening tests such as nucleic acid tests is examined, along with the concept of residual risk. Finally, considerations in acquiring informed consent in the use of kidneys from IIRDs in children and young people are discussed.

Prevention, diagnosis, and management of donor derived infections in pediatric kidney transplant recipients

Donor derived infections (DDIs) in pediatric kidney transplant recipients remain challenging to diagnose and can result in serious morbidity and mortality. This review summarizes the current guidelines and recommendations for prevention, diagnosis, and treatment of unexpected DDIs in pediatric kidney transplant recipients. We provide a contemporary overview of DDI terminology, surveillance, epidemiology, and recommended approaches for assessing these rare events with an emphasis on the pediatric recipient. To address prevention and risk mitigation, important aspects of donor and pediatric candidate evaluations are reviewed, including current Organ Procurement and Transplantation Network (OPTN) and American Society of Transplantation (AST) recommendations. Common unexpected DDI encountered by pediatric transplant teams including multi-drug resistant organisms, tuberculosis, syphilis, West Nile Virus, toxoplasmosis, Chagas disease, strongyloidiasis, candidiasis, histoplasmosis, coccidioidomycosis, and emerging infections such as COVID-19 are discussed in detail. Finally, we consider the general challenges with management of DDIs and share our experience with a novel application of next generation sequencing (NGS) of microbial cell-free DNA that will likely define a future direction in this field.

Characteristics and Donation Outcomes of Potential Organ Donors Perceived to Be at Increased Risk for Blood-borne Virus Transmission: An Australian Cohort Study 2010-2018

BACKGROUND

Safely increasing organ donation to meet need is a priority. Potential donors may be declined because of perceived blood-borne virus (BBV) transmission risk. With hepatitis C (HCV) curative therapy, more potential donors may now be suitable. We sought to describe potential deceased donors with increased BBV transmission risk.

METHODS

We conducted a cohort study of all potential organ donors referred in NSW, Australia, 2010-2018. We compared baseline risk potential donors to potential donors with increased BBV transmission risk, due to history of HIV, HCV or hepatitis B, and/or behavioral risk factors.

RESULTS

There were 624 of 5749 potential donors (10.9%) perceived to have increased BBV transmission risk. This included 298 of 5749 (5.2%) with HCV (including HBV coinfections) and 239 of 5749 (4.2%) with increased risk behaviors (no known BBV). Potential donors with HCV and those with increased risk behaviors were younger and had fewer comorbidities than baseline risk potential donors (P < 0.001). Many potential donors (82 with HCV, 38 with risk behaviors) were declined for donation purely because of perceived BBV transmission risk. Most were excluded before BBV testing. When potential donors with HCV did donate, they donated fewer organs than baseline risk donors (median 1 versus 3, P < 0.01), especially kidneys (odds ratio 0.08, P < 0.001) and lungs (odds ratio 0.11, P = 0.006).

CONCLUSIONS

Many potential donors were not accepted because of perceived increased BBV transmission risk, without viral testing, and despite otherwise favorable characteristics. Transplantation could be increased from potential donors with HCV and/or increased risk behaviors.

Public health service increased risk donor kidney grafts for transplant into children, a survey of pediatric nephrologists

BACKGROUND

Kidney transplant is the best treatment for end-stage renal disease (ESRD); however, access is limited by severe organ shortage. Public Health Service increased risk donors (PHS-IRD) represent a significant portion of available organs which are discarded at disproportional rates.

METHODS

Pediatric nephrologists were surveyed regarding PHS-IRD kidneys to understand attitudes and perceived barriers to the use of these grafts in children. We sought to elucidate what methods may help increase the likelihood of PHS-IRD acceptance.

RESULTS

Twenty-two responses were received from United States pediatric nephrologists representing 11 UNOS regions (response rate 5.9%). Of respondents, 50% had been practicing for 20+ years, 77% in academic hospitals, and 63% in cities with over 1 000 000 people. All respondents worked in an institution with a kidney transplant program. 41% reported that they would not accept PHS-IRD kidneys under any circumstance, 45% would accept depending on the candidate's medical status, and 14% routinely accepted PHS-IRD kidneys. Infectious transmission was the biggest disincentive reported (59%), with only 55% of respondents feeling comfortable counseling families on the associated risks. 82% of respondents did not perceive all PHS-IRD as the same, and 90% supported stratifying PHS-IRD into tiers based on risk, which would increase the likelihood of organ acceptance (82%) and assist in counseling families (91%).

CONCLUSIONS

With improved utilization, PHS-IRD kidneys offer a step toward decreasing the organ shortage. These findings suggest hesitance in use of PHS-IRD kidneys for pediatric recipients. Further stratification of risk could aid in provider organ acceptance and counseling patients.

Donor considerations in pediatric kidney transplantation

This article reviews kidney transplant donor options for children with end-stage kidney disease (ESKD). Global access to kidney transplantation is variable. Well-established national policies, organizations for organ procurement and allocation, and donor management policies may account for higher deceased donor (DD transplants) in some countries. Living donor kidney transplantation (LD) predominates in countries where organ donation has limited national priority. In addition, social, cultural, religious and medical factors play a major role in both LD and DD kidney transplant donation. Most children with ESKD receive adult-sized kidneys. The transplanted kidney has a finite survival and the expectation is that children who require renal replacement therapy from early childhood will probably have 2 or 3 kidney transplants in their lifetime. LD transplant provides better long-term graft survival and is a better option for children. When a living related donor is incompatible with the intended recipient, paired kidney exchange with a compatible unrelated donor may be considered. When the choice is a DD kidney, the decision-making process in accepting a donor offer requires careful consideration of donor history, kidney donor profile index, HLA matching, cold ischemia time, and recipient's time on the waiting list. Accepting or declining a DD offer in a timely manner can be challenging when there are undesirable facts in the donor's history which need to be balanced against prolonging dialysis in a child. An ongoing global challenge is the significant gap between organ supply and demand, which has increased the need to improve organ preservation techniques and awareness for organ donation.

Changes in offer and acceptance patterns for pediatric kidney transplant candidates under the new Kidney Allocation System

Stakeholders have expressed concerns regarding decreased deceased donor kidney transplant (DDKT) rates for pediatric candidates under the Kidney Allocation System (KAS). To better understand what might be driving this, we studied Scientific Registry of Transplant Recipients kidney offer data for 3642 pediatric (age <18 years) kidney-only transplant candidates between December 31, 2012 to December 3, 2014 (pre-KAS) and December 4, 2014 to January 6, 2017 (post-KAS). We used negative binomial regression and multilevel logistic regression to compare offer and acceptance rates pre- and post-KAS. We stratified by donor age (<18, 18-34, and 35+ years) and KDPI (<35% and ≥35%) to reflect differing allocation prioritization pre-KAS and post-KAS. As might be expected from prioritization changes, post-KAS candidates were less likely to receive offers for donors 18-34 years old with KDPI ≥ 35% (adjusted incidence rate ratio [aIRR]: 0.18 0.210.25 , P < .001), and more likely to receive offers for donors 18-34 years old and KDPI < 35% (aIRR: 1.12 1.201.29 , P < .001). However, offer acceptance practices also changed post-KAS: kidneys from donors 18-34 years old and KDPI < 35% were 23% less likely to be accepted post-KAS (adjusted odds ratio: 0.61 0.770.98 , P = .03). Using kidneys from donors 18-34 years old with KDPI < 35% post-KAS to the same extent they were used pre-KAS might be an effective strategy to mitigate any decrease in DDKT rates for pediatric candidates.

Assessing Solid Organ Donors and Monitoring Transplant Recipients for Human Immunodeficiency Virus, Hepatitis B Virus, and Hepatitis C Virus Infection - U.S. Public Health Service Guideline, 2020

The recommendations in this report supersede the U.S Public Health Service (PHS) guideline recommendations for reducing transmission of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) through organ transplantation (Seem DL, Lee I, Umscheid CA, Kuehnert MJ. PHS guideline for reducing human immunodeficiency virus, hepatitis B virus, and hepatitis C virus transmission through organ transplantation. Public Health Rep 2013;128:247-343), hereafter referred to as the 2013 PHS guideline. PHS evaluated and revised the 2013 PHS guideline because of several advances in solid organ transplantation, including universal implementation of nucleic acid testing of solid organ donors for HIV, HBV, and HCV; improved understanding of risk factors for undetected organ donor infection with these viruses; and the availability of highly effective treatments for infection with these viruses. PHS solicited feedback from its relevant agencies, subject-matter experts, additional stakeholders, and the public to develop revised guideline recommendations for identification of risk factors for these infections among solid organ donors, implementation of laboratory screening of solid organ donors, and monitoring of solid organ transplant recipients. Recommendations that have changed since the 2013 PHS guideline include updated criteria for identifying donors at risk for undetected donor HIV, HBV, or HCV infection; the removal of any specific term to characterize donors with HIV, HBV, or HCV infection risk factors; universal organ donor HIV, HBV, and HCV nucleic acid testing; and universal posttransplant monitoring of transplant recipients for HIV, HBV, and HCV infections. The recommendations are to be used by organ procurement organization and transplant programs and are intended to apply only to solid organ donors and recipients and not to donors or recipients of other medical products of human origin (e.g., blood products, tissues, corneas, and breast milk). The recommendations pertain to transplantation of solid organs procured from donors without laboratory evidence of HIV, HBV, or HCV infection. Additional considerations when transplanting solid organs procured from donors with laboratory evidence of HCV infection are included but are not required to be incorporated into Organ Procurement and Transplantation Network policy. Transplant centers that transplant organs from HCV-positive donors should develop protocols for obtaining informed consent, testing and treating recipients for HCV, ensuring reimbursement, and reporting new infections to public health authorities.

The impact of public health service increased risk donors in pediatric liver transplantation

Many transplant programs are reluctant to use organs from deceased donors designated as "PHS increased risk" due to misconceptions regarding the quality of those organs. This study evaluated the impact of PHS increased risk donors on patient and allograft survival in pediatric patients undergoing liver transplantation. Retrospective analysis of the UNOS database from January 2005 through September 2017 revealed 5615 pediatric patients who underwent isolated liver transplantation; of these, 5057 patients received primary isolated liver transplants and 558 patients received isolated liver retransplants. PHS increased risk organs were used in 6.7% and 5.4% of the children receiving primary isolated and retransplant livers, respectively. Cox proportional hazards models adjusted for donor and recipient characteristics determined the relative risk of PHS status on allograft and patient survival. Sicker children (those in ICU [P < .001] and on life support [P = .04]) were more likely to receive PHS increased risk donor organs. There were no differences in overall patient (P = .61) or allograft (P = .68) survival between pediatric patients receiving PHS positive vs PHS negative deceased donor organs; adjusted models also demonstrated no statistically significant differences in patient or allograft survival. Excellent patient and allograft survival can be accomplished with PHS increased risk organs.

Residual risk of infection with blood-borne viruses in potential organ donors at increased risk of infection: systematic review and meta-analysis

OBJECTIVE

To estimate the prevalence and incidence of human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus (HBV) among people at increased risk of infection in Australia; to estimate the residual risk of infection among potential solid organ donors in these groups when their antibody and nucleic acid test results are negative.

STUDY DESIGN

Systematic review and meta-analysis of reports of the incidence and prevalence of HIV, HCV, and HBV in groups at increased risk of infection in Australia.

DATA SOURCES

MEDLINE, government and agency reports, Australasian Society for HIV, Viral Hepatitis and Sexual Health Medicine conference abstracts, the Australian New Zealand Clinical Trial Registry, and National Health and Medical Research Council grants published 1 January 2000 - 14 February 2019; personal communications.

DATA SYNTHESIS

Residual risk of HIV infection was highest among men who have sex with men (4.8 [95% CI, 2.7-6.9] per 10 000 antibody-negative persons; 1.5 [95% CI, 0.9-2.2] per 10 000 persons who are both antibody- and nucleic acid-negative). Residual risk of HCV infection was highest among injecting drug users (289 [95% CI, 191-385] per 10 000 antibody-negative persons; 20.9 [95% CI, 13.8-28.0] per 10 000 antibody- and nucleic acid-negative persons). Residual risk for HBV infection was highest among injecting drug users (98.6 [95% CI, 36.4-213] per 10 000 antibody-negative people; 49.4 [95% CI, 18.2-107] per 10 000 persons who were also nucleic acid-negative).

CONCLUSIONS

Absolute risks of window period viral infections are low in people from Australian groups at increased risk but with negative viral test results. Accepting organ donations by people at increased risk of infection but with negative viral test results could be considered as a strategy for expanding the donor pool.

REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO), CRD42017069820.