Neonatal organ donation: Retrospective audit into potential donation in a single neonatal unit

BACKGROUND

Research has shown that many babies who die in neonatal units could have been potential tissue and/or organ donors. Despite the existence of guidelines supporting its implementation, the incidence of neonatal donation remains rare in the United Kingdom.

AIM

The aim of this audit was to retrospectively determine potential eligibility for neonatal tissue and/or organ donation referral in infants who died in a single UK tertiary-level neonatal unit between 2012 and 2021. Cause of death and documentation of any discussions held regarding referral for donation were also explored.

STUDY DESIGN

An audit was undertaken to identify all neonatal deaths at a single tertiary-level NICU in London from 2012-2021. Infants who retrospectively could have been referred as potential tissue and/or organ donors were identified using current NHS Blood and Transplant inclusion and exclusion criteria.

RESULTS AND CONCLUSION

A significant missed potential for neonatal tissue and/or organ donation referrals was identified, which is likely not just limited to the unit audited. Causes of death were as expected for a tertiary level neonatal unit and centre for therapeutic cooling of babies born with hypoxic perinatal brain injuries. Only one documented conversation was found regarding neonatal donation.

RELEVANCE TO CLINICAL PRACTICE

To enable conversations regarding neonatal donation to become a routine part of end-of-life care discussions with families as appropriate, good links between neonatal healthcare professionals and Specialist Nurses in Organ Donation need to be established. This will facilitate the referral of all suitable neonates as potential donors and ensure that neonatal staff feel supported to care for babies identified as potential donors.

Rescue Allocation Modes in Eurotransplant Kidney Transplantation: Recipient Oriented Extended Allocation Versus Competitive Rescue Allocation-A Retrospective Multicenter Outcome Analysis

BACKGROUND

Whenever the kidney standard allocation (SA) algorithms according to the Eurotransplant (ET) Kidney Allocation System or the Eurotransplant Senior Program fail, rescue allocation (RA) is initiated. There are 2 procedurally different modes of RA: recipient oriented extended allocation (REAL) and competitive rescue allocation (CRA). The objective of this study was to evaluate the association of patient survival and graft failure with RA mode and whether or not it varied across the different ET countries.

METHODS

The ET database was retrospectively analyzed for donor and recipient clinical and demographic characteristics in association with graft outcomes of deceased donor renal transplantation (DDRT) across all ET countries and centers from 2014 to 2021 using Cox proportional hazards methods.

RESULTS

Seventeen thousand six hundred seventy-nine renal transplantations were included (SA 15 658 [89%], REAL 860 [4.9%], and CRA 1161 [6.6%]). In CRA, donors were older, cold ischemia times were longer, and HLA matches were worse in comparison with REAL and especially SA. Multivariable analyses showed comparable graft and recipient survival between SA and REAL; however, CRA was associated with shorter graft survival. Germany performed 76% of all DDRTs after REAL and CRA and the latter mode reduced waiting times by up to 2.9 y.

CONCLUSIONS

REAL and CRA are used differently in the ET countries according to national donor rates. Both RA schemes optimize graft utilization, lead to acceptable outcomes, and help to stabilize national DDRT programs, especially in Germany.

Public Opinions on Removing Disincentives and Introducing Incentives for Organ Donation: Proposing a European Research Agenda

The shortage of organs for transplantations is increasing in Europe as well as globally. Many initiatives to the organ shortage, such as opt-out systems for deceased donation and expanding living donation, have been insufficient to meet the rising demand for organs. In recurrent discussions on how to reduce organ shortage, financial incentives and removal of disincentives, have been proposed to stimulate living organ donation and increase the pool of available donor organs. It is important to understand not only the ethical acceptability of (dis)incentives for organ donation, but also its societal acceptance. In this review, we propose a research agenda to help guide future empirical studies on public preferences in Europe towards the removal of disincentives and introduction of incentives for organ donation. We first present a systematic literature review on public opinions concerning (financial) (dis)incentives for organ donation in European countries. Next, we describe the results of a randomized survey experiment conducted in the United States. This experiment is crucial because it suggests that societal support for incentivizing organ donation depends on the specific features and institutional design of the proposed incentive scheme. We conclude by proposing this experiment's framework as a blueprint for European research on this topic.

Examining Corneal Tissue Exportation Fee and Its Impact on Equitable Allocation

METHODS

We conducted grounded theory semistructured interviews, purposively inviting participants until themed saturation was met. Sentiment analysis was used to determine opinion.

RESULTS

We interviewed n = 92 global eye tissue and eye bank professionals. We determined that corneal tissue, which is exported, costs between US $100 and US $6000 or is provided as gratis. Collectively, interviewees indicated that, globally, there were no fixed fee structures in place, and the fee was influenced by multiple factors on both export and import sides. They indicated that ultimately corneas were allocated based on the importers' ability to pay the price determined by the exporting eye bank.

DISCUSSION

Allocation of corneal tissue, which is exported, is influenced by the fees charged by the exporters to meet their bottom line and the funds available to importers. Therefore, export allocation is not equitable, with those who can pay a higher fee, prioritized. Steps to guide and support exporters with the development of fee structures that promote equitable allocation are essential. This will assist both export and import eye bank development, corneal tissue access development, and those awaiting a corneal transplant.

Encouraging Outcomes of Alternate Donor Hematopoietic Stem Cell Transplant in Pediatric High-risk/Relapsed Leukemias: A Single Center Experience

Outcomes of high-risk and relapsed pediatric acute leukemias continue to be suboptimal. Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative modality. However, <30% of patients have matched sibling donors available. Hence, alternate donors (matched unrelated and haploidentical) are being used to improve outcomes. We retrospectively analyzed our data of all children with high-risk/relapsed acute leukemias who underwent alternate donor HSCT at our center from April 2015 to July 2020. A total of 15 patients were included-3 underwent matched unrelated and 12 underwent haploidentical HSCT. Before HSCT, all patients were in complete remission (CR): CR1-1, CR2-11, and CR3-3. All patients engrafted except one. Median time to neutrophil and platelet engraftment was 15 and 16 days, respectively. There were 3 transplant related mortalities. One patient was lost to follow-up. Remaining 11 patients remain in remission and are alive. The cumulative incidence of acute graft versus host disease was 57.1% and of chronic graft versus host disease was 21.4%. Overall survival was 80% and the event-free survival was 73.3%. The median follow-up of alive patients was 775 days (range: 333 to 2077 d). Our experience shows encouraging outcomes using alternate donor HSCT for these patients from developing world.

The new world: hematopoietic stem cell transplant during a pandemic

PURPOSE OF REVIEW

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) impacted every facet of hematopoietic cell transplantation. This article reviews the adjustments to recipient and donor care that occurred in response to this unprecedented event.

RECENT FINDINGS

Transplant centers modified algorithms, patient flow, education, and how we provided care. Our donor center partners reworked how donors were evaluated and products delivered to the transplant center. Our professional societies provided guidelines for patient and donor care and rapidly modified these based upon the never-ending stream of new data learned about SARS-CoV-2. Our research organizations provided rapid analyses to ensure the care modifications necessitated did not have a profound negative impact on our patients or donors.

SUMMARY

The efforts of transplant providers and donor centers worldwide allowed patients to receive the transplant needed with assurances that they were receiving the best care available despite the worldwide challenge.

Supply and Demand of Domestic Corneal Tissue and Its Implications on Export Potential-Using Australia as an Example

PURPOSE

Corneal tissue importation is only possible if another country is able to export corneas without impacting its own domestic demand. Currently, there is little evidence to indicate whether export nations have such surplus capacity and in a position to export. To explore this concept, we examined our nation, Australia, which is reported to routinely decline donations because of its ability to meet domestic corneal transplant demand. Our research offers insights and opportunities for Australia and other nations to evaluate their domestic and international supply and allocation of corneal tissue in this space.

METHOD

We collated 12 months of data on collected and noncollected donations, through participating Australian Eye Banks. The explanation of why some known donors were declined or not pursued indicated if demand was met and potential surplus-for-export levels.

RESULTS

There were 7.5% (n = 11,889) of deaths in Australia that were notified to Australian Eye Banks during our reporting period. Of those, 9.3% (n = 1106/11,889) were recovered and allocated, 15.7% (n = 1863/11,889) were known but declined, and 75% (n = 8920/11,889) were not pursued. Of those that were declined, 64.3% (n = 1197/1863) were declined because of limitations with service/manpower at the eye bank, whereas 35.7% (n = 666/1863) were declined because demand was met.

CONCLUSIONS

Australia did not meet demand all the time, during our data period. There were adequate quantities of potential donors to support increasing recovery for domestic allocation and provide for exportation without hindrance to Australian demand. Further examination of domestic supply and demand cycles and the export process is required before routine exportation.

Pathways to Clinical Cardiac Xenotransplantation

Heart transplantation is the only long-lasting lifesaving option for patients with terminal cardiac failure. The number of available human organs is however far below the actual need, resulting in substantial mortality of patients while waiting for a human heart. Mechanical assist devices are used to support cardiac function but are associated with a high risk of severe complications and poor quality of life for the patients. Consistent success in orthotopic transplantation of genetically modified pig hearts into baboons indicates that cardiac xenotransplantation may become a clinically applicable option for heart failure patients who cannot get a human heart transplant. In this overview, we project potential paths to clinical cardiac xenotransplantation, including the choice of genetically modified source pigs; associated requirements of microbiological, including virological, safety; optimized matching of source pig and recipient; and specific treatments of the donor heart after explantation and of the recipients. Moreover, selection of patients and the regulatory framework will be discussed.

Recommendations for Donor and Recipient Selection and Risk Prediction: Working Group Report From the ILTS Consensus Conference in DCD Liver Transplantation

Although the utilization of donation after circulatory death donors (DCDs) for liver transplantation (LT) has increased steadily, much controversy remains, and no common acceptance criteria exist with regard to donor and recipient risk factors and prediction models. A consensus conference was organized by International Liver Transplantation Society on January 31, 2020, in Venice, Italy, to review the current clinical practice worldwide regarding DCD-LT and to develop internationally accepted guidelines. The format of the conference was based on the grade system. International experts in this field were allocated to 6 working groups and prepared evidence-based recommendations to answer-specific questions considering the currently available literature. Working group members and conference attendees served as jury to edit and confirm the final recommendations presented at the end of the conference by each working group separately. This report presents the final statements and recommendations provided by working group 2, covering the entire spectrum of donor and recipient risk factors and prediction models in DCD-LT.

Predicting Kidney Discard Using Machine Learning

BACKGROUND

Despite the kidney supply shortage, 18%-20% of deceased donor kidneys are discarded annually in the United States. In 2018, 3569 kidneys were discarded.

METHODS

We compared machine learning (ML) techniques to identify kidneys at risk of discard at the time of match run and after biopsy and machine perfusion results become available. The cohort consisted of adult deceased donor kidneys donated between December 4, 2014, and July 1, 2019. The studied ML models included Random Forests (RF), Adaptive Boosting (AdaBoost), Neural Networks (NNet), Support Vector Machines (SVM), and K-nearest Neighbors (KNN). In addition, a Logistic Regression (LR) model was fitted and used for comparison with the ML models' performance.

RESULTS

RF outperformed other ML models. Of 8036 discarded kidneys in the test dataset, LR correctly classified 3422 kidneys, whereas RF correctly classified 4762 kidneys (area under the receiver operative curve [AUC]: 0.85 versus 0.888, and balanced accuracy: 0.681 versus 0.759). For the kidneys with kidney donor profile index of >85% (6079 total), RF significantly outperformed LR in classifying discard and transplant prediction (AUC: 0.814 versus 0.717, and balanced accuracy: 0.732 versus 0.657). More than 388 kidneys were correctly classified using RF. Including biopsy and machine perfusion variables improved the performance of LR and RF (LR's AUC: 0.888 and balanced accuracy: 0.74 versus RF's AUC: 0.904 and balanced accuracy: 0.775).

CONCLUSIONS

Kidneys that are at risk of discard can be more accurately identified using ML techniques such as RF.

Suggested Patient Selection Criteria for Initial Clinical Trials of Pig Kidney Xenotransplantation in the United States

There is a critical shortage of kidneys for transplantation into patients with kidney failure. Genetically-engineered pigs could provide an additional source. Increasing success is being reported of the transplantation of pig kidneys in nonhuman primates. Consideration is now being given to the selection of patients for the first clinical trial of pig kidney transplantation. In some US states, patients aged 55–65, particularly if of blood group O, may wait >5 years for a donor organ, by which time >50% are likely to have died or removed from the wait-list because they are no longer acceptable for transplantation. We suggest these patients, if otherwise healthy, might accept the opportunity of early pig kidney transplantation.

Impact of the COVID-19 Pandemic on Keratoplasty and Corneal Eye Banking

PURPOSE

The purpose of this study was to assess the impact of COVID-19 guidelines for corneal donor tissue screening and the utility of routine postmortem COVID-19 testing of donors intended for surgical use at a single eye bank.

METHODS

A retrospective analysis of referrals to and eligible donors from an eye bank between March 1, 2020, and June 30, 2020, was performed, with the same time period in 2019 as a control. Referrals who were not procured because of Eye Bank Association of America COVID-19 guidelines and eye bank-specific restrictions were noted. The results of 1 month of routine postmortem testing performed by the eye bank were examined. Analysis of variance tests were performed to assess the change between donors from 2019 to 2020.

RESULTS

There was a significant reduction in both the number of total referrals to the eye bank (P = 0.044) and donors eligible for surgical transplantation (P = 0.031). Eye Bank Association of America COVID-19 guidelines reduced the number of referrals over this period by 4% to 14%. Of the 266 surgically eligible donors who received postmortem COVID-19 testing in June by the eye bank, 13 resulted positive (4.9%).

CONCLUSIONS

Despite a reduction in referrals and eligible corneal transplant donors at a single eye bank, there was a surplus of surgically suitable corneal tissue during the first wave of the COVID-19 pandemic. Eye banks should consider routine postmortem COVID-19 testing to identify asymptomatic infected donors although the risk of transmission of COVID-19 from infected donors is unknown.

Role of Reverse Transcriptase Polymerase Chain Reaction in Cornea Donors During the COVID-19 Pandemic

PURPOSE

The purpose of this study was to report the analysis of reverse transcriptase polymerase chain reaction (RT-PCR) of nasopharyngeal (NP) samples of cornea donors dying because of causes unrelated to severe acute respiratory coronavirus (SARS-CoV-2).

METHODS

A retrospective analysis of all cornea donors dying from causes other than SARS-CoV-2 between August 2020 and December 2020 was performed. Informed consent was obtained from the next of kin of the deceased for RT-PCR testing from NP swabs. Rapid antigen testing from all the deceased was performed before in situ cornea excision. In addition, NP samples in viral transport media for RT-PCR were also collected for SARS-CoV-2 analysis. Corneas were released from the eye bank only after a negative RT-PCR report.

RESULT

One hundred eighteen corneas from 59 donors were obtained by the eye bank. Eleven donors (18.64%) were positive for SARS-CoV-2 on RT-PCR testing. Six of these 11 donors had a Ct value of E gene less than 25.

CONCLUSIONS

NP samples of cornea donors dying due to causes other than coronavirus disease-19 were positive for SARS-CoV-2 on RT-PCR. This implicates that donors could be having asymptomatic/undetected coronavirus disease infection. We recommend adding the routine testing of NP samples of all cornea donors in the eye banking protocol in this ongoing SARS-CoV-2 pandemic.

Trends in Bone Marrow Donor Registration in Japan Following a Celebrity's Disclosure of Leukemia

This cohort study examines the association of a celebrity’s public disclosure of an acute lymphocytic leukemia diagnosis and trends in bone marrow donor registration in Japan.

Heart Donation From Donors After Controlled Circulatory Death

The gold-standard therapy for advanced-stage heart failure is cardiac transplantation. Since the first heart transplant in 1967, the majority of hearts transplanted came from brain death donors. Nevertheless, in recent years, the option of donation after circulatory death (DCD) is gaining importance to increase donor pool. Currently, heart-transplant programs using controlled donation after circulatory death (cDCD) have been implemented in the United Kingdom, Belgium, Australia, United States of America, and, recently, in Spain. In this article, we performed a concise review of the literature in heart cDCD; we summarize the pathophysiology involved in ischemia and reperfusion injury during this process, the different techniques of heart retrieval in cDCD donors, and the strategies that can be used to minimize the damage during retrieval and until transplantation. Heart transplant using DCD hearts is in continuous improvement and must be implemented in experienced cardiac transplant centers.

Updated safety precautions and guidance on eye banking procedures during the coronavirus disease 2019 pandemic

PURPOSE OF REVIEW

severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly infectious coronavirus causing the COVID-19 pandemic. Although airborne spread through infectious respiratory droplets is the primary source of transmission, recent literature has suggested the ocular surface may be able to harbor viral particles. Here, we aim to discuss how SARS-CoV-2 affects the ocular surface and updated guidance on how SARS-CoV-2 transmission should be considered in the setting of eye banking and corneal transplantation procedures.

RECENT FINDINGS

SARS-CoV-2 RNA can be found on the ocular surface, which may suggest the eye as a site of viral replication. However, there is poor correlation between PCR positivity on the ocular surface and ocular symptoms. To date, although viral particles can be found on the ocular surface, use of standard antiseptic procedures during corneal tissue procurement appears to sufficiently reduce viral load. In addition, preprocedure testing may further decrease the chances of transplanting an infected cornea without significantly impacting the overall accessibility to corneal tissue by decreasing the donor pool.

SUMMARY

Corneal transplantation remains a well tolerated and highly successful procedure with no evidence of viral transmission with transplantation. Although the ocular surface has the required receptors to allow for viral replication, there is no clear evidence that the eye is a site for primary viral infection.

The evolving landscape of donor egg treatment: success, women's choice, and anonymity

PURPOSE

To analyze donor oocyte (DE) data across 6 years for oocyte usage efficiency, trends, and whether changes impacted outcomes.

METHODS

From 2014 to 2019, 323 DE embryo transfers were completed in 200 recipients using oocytes derived of 163 donors. We assessed data for oocytes being freshly retrieved (FRESH-EGG) vs. purchased frozen (FROZEN-EGG); embryos transferred fresh (FRESH-ET) vs. frozen (FROZEN-ET); cycles SHARED (two recipients) vs. SOLE (one recipient); single (SET) vs. double (DET) embryo transfers and usage of PGT-A. Primary outcome was ongoing pregnancy plus live birth (OP/LB) rate.

RESULTS

A total of 229 FRESH-EGG (70%) and 94 FROZEN-EGG (30%) cycles were completed. Overall, the use of FRESH-EGG yielded a higher OP/LB compared to FROZEN-EGG (49% vs. 30%, p = 0.001); within the FRESH-EGG group, OP/LB was similar when comparing FRESH-ET vs. FROZEN-ET (58% vs. 45%, p = 0.07). Within the FRESH-ET group, those using FRESH-EGG had a higher OP/LB than those using FROZEN-EGG (58% vs. 27%, p < 0.001). SHARED vs. SOLE cycles (p = 0.6), donor age (21-32 years; p = 0.4), and age of intended parents (maternal p = 0.3, paternal p = 0.2) did not significantly impact OP/LB. Notably, the use of PGT-A did not improve odds for an OP/LB (p = 0.7).

CONCLUSION

The use of FRESH-EGG with FRESH-ET without PGT-A remains superior to newer DE treatment combinations. Specifically, the use of FROZEN-EGG and PGT-A did not improve outcomes. Although changing DE practices may enhance experience and affordability, patients and providers must appreciate that choices do not always favorably impact success. Additionally, newly available genetic-ancestry testing may pose longer-term ramifications mandating change in treatment and/or counseling.

Validation of High-Sensitivity Severe Acute Respiratory Syndrome Coronavirus 2 Testing for Stool-Toward the New Normal for Fecal Microbiota Transplantation

INTRODUCTION

Mounting evidence demonstrates potential for fecal-oral transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The US Food and Drug Administration now requires SARS-CoV-2 testing of potential feces donors before the use of stool manufactured for fecal microbiota transplantation. We sought to develop and validate a high-sensitivity SARS-CoV-2 reverse transcriptase polymerase chain reaction (RT-PCR) procedure for testing stool specimens.

METHODS

A modified extraction method was used with an RT-PCR assay adapted from the Centers for Disease Control and Prevention PCR protocol for respiratory specimens. Contrived specimens were created using pre-COVID-19 banked stool specimens and spiking in known concentrations of SARS-CoV-2-specific nucleic acid. The highest transcript concentration at which 2/2 or 1/2 SARS-CoV-2 targets were detected in 9/10 replicates was defined as the dual-target limit and single-target limit of detection, respectively. The clinical performance of the assay was evaluated with stool samples collected from 17 nasopharyngeal swab RT-PCR-positive patients and 14 nasopharyngeal RT-PCR-negative patients.

RESULTS

The dual-target and single-target limit of detection were 56 copies/μL and 3 copies/μL, respectively. SARS-CoV-2 was detected at concentrations as low as 0.6 copies/μL. Clinical stool samples from known COVID-19-positive patients demonstrated the detection of SARS-CoV-2 in stool up to 29 days from symptom onset with a high agreement with nasopharyngeal swab tests (kappa statistic of 0.95, P value < 0.001).

DISCUSSION

The described RT-PCR test is a sensitive and flexible approach for the detection of SARS-CoV-2 in stool specimens. We propose an integrated screening approach that incorporates this stool test to support continuation of fecal microbiota transplantation programs.

The Introduction of cPRA and Its Impact on Access to Deceased Donor Kidney Transplantation for Highly Sensitized Patients in Australia

BACKGROUND

In March 2016, Australia's deceased donor kidney allocation program introduced calculated panel reactive antibody (cPRA) based on antibody exclusions using multiplex assays to define sensitization for waitlisted candidates. We aimed to assess the impact of this change and review access to transplantation for highly sensitized patients under the current allocation rules.

METHODS

Registry data were used to reconstruct changes in panel reactive antibody (PRA)/cPRA for all patients active on the waiting list between 2013 and 2018. A multilevel, mixed-effects negative binomial regression model was used to determine the association between sensitization and transplantation rate in the cPRA era.

RESULTS

Following the introduction of cPRA, there was an increase in the percentage of the waiting list classified as highly sensitized (PRA/cPRA ≥80%) from 7.2% to 27.8% and very highly sensitized (PRA/cPRA ≥99%) from 2.7% to 15.3%. Any degree of sensitization was associated with a decreased rate of transplantation with a marked reduction for those with cPRA 95%-98% (adjusted incidence rate ratio, 0.36 [95% confidence interval, 0.28-0.47], P < 0.001) and cPRA ≥99% (adjusted incidence rate ratio, 0.09 [95% confidence interval, 0.07-0.12], P < 0.001).

CONCLUSIONS

The proportion of the waiting list classified as highly sensitized increased substantially following the introduction of cPRA, and despite current prioritization, very highly sensitized patients have markedly reduced access to deceased donor transplantation.

Liver Transplantation of HCV-viremic Donors Into HCV-negative Recipients in the United States: Increasing Frequency With Profound Geographic Variation

BACKGROUND

Direct-acting antiviral therapy made possible the novel practice of utilizing hepatitis C virus (HCV)-viremic (HCV RNA-positive) donors into HCV-negative recipients in the United States. Although initial reports of outcomes have been satisfactory, higher-quality longer-term outcomes remain to be elucidated.

METHODS

National data were examined from the Organ Procurement and Transplantation Network on adult patients in the United States who underwent a primary, single organ, deceased donor liver transplant from January 1, 2016 to March 31, 2020. Outcomes of HCV-negative recipients (R-) who received an allograft from donors who were HCV RNA-positive (D HCV+) donors were compared with HCV RNA-negative (D HCV-) donors.

RESULTS

There has been a 35-fold increase in D HCV+/R- liver transplants over the past 4 y in the United States, from 8 in 2016 to 280 in 2019. There was an almost 6-fold difference in this practice among UNOS geographic regions. Graft survival following D HCV+/R- liver transplantation was excellent, with 1-y rates being 91% and 90% and 2-y rates being 88.5% and 87% for D HCV+/R- and D HCV-/R-, respectively (P = 0.672). In multivariate analysis, adjusting for other donor and recipient attributes, D HCV+/R- was not associated with patient or graft survival.

CONCLUSIONS

The practice of D HCV+/R- continues to increase without discernible impact on medium-term outcomes. Notable geographic variation exists, suggesting inconsistent perceptions about the impact of D HCV+/R- transplantation on outcomes. These results strengthen the perceived safety in utilizing HCV-viremic donor organs as a donor pool expansion strategy, not only in the United States, but also worldwide.

Ex Vivo Lung Perfusion: Current Achievements and Future Directions

There is a severe shortage in the availability of donor organs for lung transplantation. Novel strategies are needed to optimize usage of available organs to address the growing global needs. Ex vivo lung perfusion has emerged as a powerful tool for the assessment, rehabilitation, and optimization of donor lungs before transplantation. In this review, we discuss the history of ex vivo lung perfusion, current evidence on its use for standard and extended criteria donors, and consider the exciting future opportunities that this technology provides for lung transplantation.

Donor Factors Associated with Familial Consent for Organ Donation among Trauma Casualties: a 10-Year Retrospective Study

BACKGROUND

Consent rates for organ donation remain one of the most important factors determining the number of organs available for transplantation. Trauma casualties constitute a substantial part of the deceased organ donor pool and have unique characteristics that distinguish them from the general donor population. However, this group has not been extensively studied.

OBJECTIVES

To identify donor factors associated with positive familial consent for solid organ donation among trauma casualties.

METHODS

This retrospective study included all trauma casualties who were admitted to the Rabin Medical Center, Beilinson hospital, during the period from January 2008 to December 2017, who were potential organ donors. Data collected included demographic features, the nature of the injury, surgical interventions, and which organs were donated. Data was collected from the Rabin Medical Center Trauma Registry.

RESULTS

During the study period 24,504 trauma patients were admitted and 556 died over their hospital course. Of these 76 were potential donors, of whom 32 became actual donors and donated their organs. Two factors showed a statistically significant correlation to donation, namely female gender (P = 0.018) and Jewish religion of the deceased (P = 0.032).

CONCLUSIONS

Only a small group of in hospital trauma deaths were potential solid organ donors (13.7%) and less than half of these became actual donors. Consent rates were higher when the deceased was female or Jewish.

Recipient pre-existing chronic hypotension is associated with delayed graft function and inferior graft survival in kidney transplantation from elderly donors

Background

Pre-existing chronic hypotension affects a percentage of kidney transplanted patients (KTs). Although a relationship with delayed graft function (DGF) has been hypothesized, available data are still scarce and inconclusive.

Methods

A monocentric retrospective observational study was performed on 1127 consecutive KTs from brain death donors over 11 years (2003–2013), classified according to their pre-transplant Mean Blood Pressure (MBP) as hypotensive (MBP < 80 mmHg) or normal-hypertensive (MBP ≥ 80 mmHg, with or without effective antihypertensive therapy).

Results

Univariate analysis showed that a pre-existing hypotension is associated to DGF occurrence (p<0.01; OR for KTs with MBP < 80 mmHg, 4.5; 95% confidence interval [CI], 2.7 to 7.5). Chronic hypotension remained a major predictive factor for DGF development in the logistic regression model adjusted for all DGF determinants. Adjunctive evaluations on paired grafts performed in two different recipients (one hypotensive and the other one normal-hypertensive) confirmed this assumption. Although graft survival was only associated with DGF but not with chronic hypotension in the overall population, stratification according to donor age revealed that death-censored graft survival was significantly lower in hypotensive patients who received a KT from >50 years old donor.

Conclusions

Our findings suggest that pre-existing recipient hypotension, and the subsequent hypotension-related DGF, could be considered a significant detrimental factor, especially when elderly donors are involved in the transplant procedure.

Geographic Differences in Lung Transplant Volume and Donor Availability During the COVID-19 Pandemic

BACKGROUND

Regional variation in lung transplantation practices due to local coronavirus disease 2019 (COVID-19) prevalence may cause geographic disparities in access to lung transplantation.

METHODS

Using the United Network for Organ Sharing registry, we conducted a descriptive analysis of lung transplant volume, donor lung volume, new waitlist activations, and waiting list deaths at high-volume lung transplant centers during the first 3 months of the pandemic (March 1. 2020, to May 30, 2020) and we compared it to the same period in the preceding 5 years.

RESULTS

Lung transplant volume decreased by 10% nationally and by a median of 50% in high COVID-19 prevalence centers (range -87% to 80%) compared with a median increase of 10% (range -87% to 80%) in low prevalence centers (P-for-trend 0.006). Donation services areas with high COVID-19 prevalence experienced a greater decrease in organ availability (-28% range, -72% to -11%) compared with low prevalence areas (+7%, range -20% to + 55%, P-for-trend 0.001). Waiting list activations decreased at 18 of 22 centers. Waiting list deaths were similar to the preceding 5 years and independent of local COVID-19 prevalence (P-for-trend 0.36).

CONCLUSIONS

Regional variation in transplantation and donor availability in the early months of the pandemic varied by local COVID-19 activity.

DCD Renal Transplantation From Donors With Acute Kidney Injury

BACKGROUND

Deceased donor kidneys with acute kidney injury (AKI) and donation after circulatory death (DCD) kidneys are viable sources of organs. The outcomes of renal transplantation from DCD donors with AKI are not known.

METHODS

A retrospective review of deceased donor renal transplants performed from 2006 to 2016 was conducted using the United Network for Organ Sharing dataset. Donors were stratified by DCD or brain dead status and by AKI stage. Recipients were followed until graft failure or the end of study. Cox regression was used to adjust for donor, recipient, and transplant covariates known to affect the incidence of delayed graft function and graft survival.

RESULTS

A total of 135 644 patients were included in the study. The odds of delayed graft function among DCD recipients were significantly higher across all donor AKI stages. The unadjusted risk of overall and death-censored graft failure were similar between the 2 groups. After adjusting for covariates, there was a significant increase in the risk of overall graft failure in recipients of DCD allografts from donors with stage 2 AKI. There was also a higher risk of death-censored graft failure among stage 1 and 2 AKI DCD recipients.

CONCLUSIONS

DCD renal allografts from donors experiencing stage 1 and 2 AKI have a higher adjusted risk of death-censored graft failure than AKI stage-matched donation after brain death renal allografts. Their use, however, is still associated with improved outcomes compared with waitlist mortality.

Changing Trends in Liver Transplantation: Challenges and Solutions

Despite improvements in postliver transplant outcomes through refinements in perioperative management and surgical techniques, several changing trends in liver transplantation have presented challenges. Mortality on the waitlist remains high. In the United States, Europe, and the United Kingdom, there is an increasing need for liver transplantation, primarily as a result of increased incidence of nonalcoholic steatohepatitis-related cirrhosis and cancer indications. Meanwhile, donor suitability has decreased, as donors are often older and have more comorbidities. Despite a mismatch between organ need and availability, many organs are discarded. Notwithstanding this, many solutions have been developed to overcome these challenges. Innovative techniques in allograft preservation, viability assessment, and reconditioning have allowed the use of suboptimal organs with adequate results. Refinements in surgical procedures, including live donor liver transplantations, have increased the organ pool and are decreasing the time and mortality on the waitlist. Despite many challenges, a similar number of solutions and prospects are on the horizon. This review seeks to explore the changing trends and challenges in liver transplantation and highlight possible solutions and future directions.

Covid-19: Emerging Considerations for Body Sourcing and Handling. A Perspective View from Nigeria

The current Coronavirus disease (Covid-19) pandemic has spread to about 220 countries of the world and has resulted in a significant number of deaths globally. Infections are still on the rise, and the impact on the global death rate could be devastating. There are fears over the likely impact of a large number of deaths on body sourcing and handling of cadavers for teaching and research. Historically, epidemics come with several challenges and have often led to some level of negligence of ethical practices and health and safety regulations associated with body sourcing and handling. The authors highlighted some emerging problems in this article, focusing on Africa and Nigeria in particular. These problems include a higher risk of coronavirus exposure for body handlers, shortage of cadavers for teaching and learning, a lack of standard regulations leading to unethical body sourcing and handling, and a lack of monitoring and collaboration needed for a well-coordinated Covid-19 pandemic response strategy. If these issues are ignored, the previous gains made in anatomical ethical practices may be destroyed. Some useful recommendations for policymaking geared toward prevention or curtailing these emerging issues have been instilled in this article.

Factors Affecting Access to the Kidney Transplant Waiting List in Eastern Hungary

Kidney transplantation is the best available treatment choice for patients suffering from end-stage renal disease; however, not all patients with end-stage renal disease have equal access to it. The aim of the study was to measure the factors that may influence access to the kidney transplant waiting list in eastern Hungary. A total of 254 patients with renal failure between 18 and 75 years old from 8 dialysis centers participated in the study. The factors associated with access to the waiting list were identified by univariate descriptive analysis and multivariate logistic regression analysis where the outcome variable was placement on the kidney transplant waiting list. Our findings demonstrates that patients registered on the waiting list were younger (odds ratio [OR] = 0.96; 95% confidence interval [CI], 0.94-0.98), were male (OR = 0.54; 95% CI, 0.30-0.98), were economically active (OR = 0.53; 95% CI, 0.29-0.98), and had greater knowledge in the field (OR = 1.17; 95% CI, 1.03-1.33). Disparity in access to the kidney transplant waiting list in Hungary does exist.

Multimedia resources to support the recruitment of committed hematopoietic stem cell donors: Perspectives of the most-needed donors

BACKGROUND

Recruitment of committed unrelated hematopoietic stem cell donors from the most-needed demographics remains a challenge for donor recruitment organizations worldwide. Multimedia resources are gaining attention as a modality to support recruitment efforts; however, there is a lack of guidance for the development of such tools. This qualitative study explores the perspectives of eligible stem cell donors on an educational whiteboard video about stem cell donation, generating insights into how whiteboard videos and related multimedia may be optimized for donor recruitment.

STUDY DESIGN AND METHODS

Eight semistructured focus groups were conducted with 38 potential donors from the most-needed demographics (young, male, and non-Caucasian) after they had watched a 3.5-minute whiteboard video explaining key concepts in stem cell donation (https://youtu.be/V4fVBtxnWfM). Constructivist grounded theory was used to identify themes and to develop a framework for understanding participants' preferred features of recruitment multimedia.

RESULTS

Participants identified a range of features contributing to the effectiveness of recruitment multimedia, adding that the whiteboard video is an effective, integrated, and readily accessible format for supporting donor recruitment. Topics that participants felt are important to address include knowledge gaps regarding donation procedures, concerns about donor safety, and the particular need for specific donor demographics. Suggested avenues for improvement include the addition of donor/recipient/patient personal experiences, attention-grabbing hooks, and a call to action including opportunities for further learning.

CONCLUSIONS

Several considerations were generated to inform the development of future multimedia for donor education/recruitment and are relevant to donor recruitment organizations worldwide.

Antibody-mediated rejection with and without donor-specific anti-human leucocyte antigen antibodies: performance of the peripheral blood 8-gene expression assay

BACKGROUND

Recently a peripheral blood 8-gene expression assay was developed for non-invasive detection of antibody-mediated rejection (ABMR) after kidney transplantation. Its value has not yet been evaluated in detail in clinical scenarios with different baseline disease probability [human leucocyte antigen donor-specific antibodies (HLA-DSA)-positive versus HLA-DSA-negative cases at the time of stable graft function versus graft dysfunction].

METHODS

Here we investigated the diagnostic accuracy of the 8-gene expression assay for histology of ABMR (ABMRh) with or without HLA-DSA in a cross-sectional cohort study of 387 blood samples with a concomitant graft biopsy.

RESULTS

In patients with HLA-DSA (n = 64), the 8-gene expression assay discriminated DSA-positive ABMRh (DSAposABMRh) cases (n = 16) with good diagnostic performance {area under the receiver operating characteristic curve [AUROC] 83.1% [95% confidence interval (CI) 70.8-95.3]}. Also, in HLA-DSA-negative samples (n = 323), a clinically relevant diagnostic performance for DSAnegABMRh cases was found (n = 30) with an AUROC of 75.8% (95% CI 67.4-84.4). The 8-gene assay did not discriminate DSAposABMRh cases from DSAnegABMRh cases. There was a net benefit for clinical decision-making when adding the 8-gene expression assay to a clinical model consisting of estimated glomerular filtration rate, proteinuria, HLA-DSA and age.

CONCLUSION

The 8-gene expression assay shows great potential for implementation in the clinical follow-up of high-risk HLA-DSA-positive patients and clinical relevance in HLA-DSA-negative cases.

Donor Characteristics and Regional Differences in the Utilization of HCV-Positive Donors in Liver Transplantation

IMPORTANCE

Increased utilization of hepatitis C virus (HCV)-positive liver allografts for liver transplant (LT) has been endorsed as one of several ways to combat national organ shortages. However, HCV-positive donors remain poorly characterized, and Organ Procurement and Transplantation Network regional differences in the utilization of HCV-positive liver allografts are unclear.

OBJECTIVE

To characterize HCV-positive donors and the allografts that come from them.

DESIGN, SETTING, AND PARTICIPANTS

In this cross-sectional study, the Scientific Registry of Transplant Recipients database was queried for all donors who underwent HCV testing from June 2015 to December 2018. Clinical and allograft characteristics were evaluated, and utilization across the United States was studied. Patients with positive or negative results for HCV antibody (Ab) and HCV nucleic acid amplification testing (NAT) were included in this study. Donors utilized for living donor transplant and pediatric (age <18 years) recipients were excluded.

MAIN OUTCOMES AND MEASURES

The primary comparison was between donors who were HCV Ab positive and those who were HCV Ab negative. Regional variations in the utilization of HCV-positive and HCV-negative donors were analyzed.

RESULTS

Of 24 500 donors utilized for LT, 1887 (7.7%) were HCV Ab positive; 64.4% of HCV Ab-positive donors were HCV NAT positive. HCV Ab-positive donors were younger (median [interquartile range] age, 35 [29-46] years vs 40 [27-54] years) and had fewer comorbidities, such as diabetes (8.3% vs 12.0%) and hypertension (25.9% vs 35.2%), compared with HCV Ab-negative donors. These findings were even more pronounced in HCV Ab-positive /NAT-positive compared with HCV Ab-positive/NAT-negative donors. Organ Procurement and Transplantation Network regions 2, 3, 10, and 11 had the highest absolute utilization of HCV Ab-positive donors, accounting for 64.4% of all HCV Ab-positive donors used in the United States. Region 1 had the highest relative utilization of HCV Ab-positive donors (18.7%). The use of HCV Ab-positive donors in some regions was associated with the rate of drug overdose, but this was not always the case. Similar utilization results were found with HCV NAT-positive donors.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, HCV-positive donors were younger and healthier than utilized HCV-negative donors. Significant differences exist in the utilization of HCV-positive donors across the 11 Organ Procurement and Transplantation Network regions, which is not entirely explained by organ demand or by higher availability of HCV-positive livers as per the distribution of the opioid epidemic. Initiatives to increase the use of HCV-positive donors, particularly in regions of high organ demand, should be implemented.

Knowledge and Attitudes Regarding Organ Transplantation Among Cyprus Residents

BACKGROUND

Organ transplantation was one of the greatest achievements of medical science during the 20th century. Knowledge, education, and culture all play prominent roles in transplantation because of the complexity of the process from donation to transplantation.

PURPOSE

The aim of this research was to determine and analyze the knowledge and attitudes about organ donation and transplantation among the general population in Limassol, Cyprus.

METHODS

A quantitative research approach was followed, and a questionnaire consisting of closed-ended questions was completed by adults from the general population in Limassol.

RESULTS

One thousand two hundred adults out of the 1,346 adults who were contacted responded to the survey (response rate: 89%) and were included as participants. Of the participants, 93.4% (p < .05) considered organ donation to be lifesaving, 57% expressed interest (and 39.8% expressed disinterest) in becoming organ donors, 80.6% (p < .05) expressed awareness of there being a waiting list for people in need of organ transplantation, 50.4% agreed that brain death must be confirmed before organ removal for transplantation, and 47% recalled having been informed about organ donation through the media, with 31.5% stating that they had never been informed about organ donation.

CONCLUSIONS

The participants demonstrated limited awareness regarding the organ donation system in Cyprus. Furthermore, a significant percentage stated that they lacked a source for obtaining related information. The Cypriot society should be informed and encouraged to participate in organ donation to increase the rate of organ transplantation.

Anesthetic Considerations During Heart Transplantation Using Donation After Circulatory Death

Worldwide, the majority of heart transplant organs are from donation after brain death. However, the shortage of suitable donors places severe limitations on this route. One option to increase the donor pool is to use organs from donation after circulatory death (DCD). Transplant centers for solid organs have been using DCD organs for years. At this time, 40% of solid organ transplantation in the United Kingdom uses organs from DCD. Use of DCD for solid organ transplants in Canada is also rising. Recently, there has been interest in using DCD organs for heart transplantation. The authors will discuss their experience of 4 heart transplants with organs from DCD donors after normothermic regional perfusion (NRP). The authors' first heart transplant using a DCD organ was in January 2020, and the fourth was in March 2020, just before the coronavirus disease 2019 (COVID-19) pandemic. The authors' protocol using NRP allows adequate evaluation of the donor heart to confidently determine organ acceptance. The co-location of the donor and the recipient in neighboring operating rooms limits ischemic times. Avoidance of an expensive ex vivo organ perfusion machine is an additional benefit for programs that may not have the resources required to purchase and maintain the machine. Some hospitals may not have the resources and space to be able to co-locate both the donor and recipient. Use of cold storage may be an option to transport the procured organ, similar to donation after brain death organs. The authors hope that this technique of NRP in DCD donors can help further increase the donor pool for heart transplantation in the United States.

Deceased Donor Liver Transplantation in India in the COVID-19 Era: Current Scenario and Future Perspectives

Coronavirus disease 2019 (COVID-19) has been recently declared a global pandemic. As of June 5, 2020, over 75,000 cases have been reported with nearly 2500 deaths in India alone. COVID-19 has severely impacted deceased donor liver transplant (DDLT) programs throughout the world. Acceptance of deceased liver donors has decreased worldwide because of the unknown risks associated with COVID-19 transmission or postoperative infection in the immediate post-transplant period, along with the risks to the health care workers in a multidisciplinary setting. In India, DDLT has come to a standstill in the setting of a national lockdown. Many national guidelines have emerged on how to safely perform transplant as well on immunosuppressive regimens and care of patients posttransplant. Here, we take a look at the current situation and summarize the different guidelines and future perspectives of DDLT in India in the COVID-19 era.

Identifying scenarios of benefit or harm from kidney transplantation during the COVID-19 pandemic: A stochastic simulation and machine learning study

Clinical decision-making in kidney transplant (KT) during the coronavirus disease 2019 (COVID-19) pandemic is understandably a conundrum: both candidates and recipients may face increased acquisition risks and case fatality rates (CFRs). Given our poor understanding of these risks, many centers have paused or reduced KT activity, yet data to inform such decisions are lacking. To quantify the benefit/harm of KT in this context, we conducted a simulation study of immediate-KT vs delay-until-after-pandemic for different patient phenotypes under a variety of potential COVID-19 scenarios. A calculator was implemented (http://www.transplantmodels.com/covid_sim), and machine learning approaches were used to evaluate the important aspects of our modeling. Characteristics of the pandemic (acquisition risk, CFR) and length of delay (length of pandemic, waitlist priority when modeling deceased donor KT) had greatest influence on benefit/harm. In most scenarios of COVID-19 dynamics and patient characteristics, immediate KT provided survival benefit; KT only began showing evidence of harm in scenarios where CFRs were substantially higher for KT recipients (eg, ≥50% fatality) than for waitlist registrants. Our simulations suggest that KT could be beneficial in many centers if local resources allow, and our calculator can help identify patients who would benefit most. Furthermore, as the pandemic evolves, our calculator can update these predictions.

Does the heart transplant have a future?

Heart failure has remained the leading cause of death globally for the last 15 years—and its prevalence will continue to rise. Fifty years ago, heart failure management was enriched by the possibility of a heart transplant. Despite impressive improvements in medical treatment for heart failure, a heart transplant remains the most effective long-lasting treatment for advanced heart failure in terms of mortality and quality of life. However, donor and recipient characteristics have changed dramatically in recent years, leading to more complex decision-making regarding organ acceptance and to more demanding operations and postoperative management. With improving pathophysiological understanding in the last decades, today’s scientific interest still focuses on basic knowledge. How to retrieve and conserve organs to minimize ischaemic injury; how best to allocate them, considering the likelihood of success (developing a heart-allocation scoring system similar to that for lung allocation); how to match donor/recipient characteristics (ABO blood-group antigen compatibility versus incompatibility); and how to avoid graft failure, rejection and secondary morbidities such as malignomas and cardiac allograft vasculopathy after the heart transplant—all these factors remain fundamental challenges in today’s transplant medicine. The use of ex vivo perfusion (e.g. via the Organ Care System^®, TransMedics, Andover, MA, USA) may play an important role in this change. Remarkably, there are huge regional divergences in current transplant practices: Whereas the number of transplants continues to rise in most Eurotransplant countries and other major transplant networks, there are some countries in which transplant numbers are static or even dropping (as in Germany). This difference results in wide variations across different countries as to how advanced heart failure is treated using mechanical circulatory-assist devices.

Addressing the Impact of the Coronavirus Disease 2019 (COVID-19) Pandemic on Hematopoietic Cell Transplantation: Learning Networks as a Means for Sharing Best Practices

The full impact of the coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), on the field of hematopoietic cell transplantation (HCT) is unknown. This perspective paper reviews the following: current COVID-19 epidemiology, diagnosis, and potential therapies; care considerations unique to HCT recipients; and the concept of a learning network to assimilate emerging guidelines and best practices and to optimize patient outcomes through facilitating shared learning and experience across transplantation centers.

Deceased Organ Donation in Syria: Challenges and Solutions

The first living-donor kidney transplant in Syria was performed 41 years ago; by 2019, 5407 renal transplants had been performed there. Three heart transplants from deceased donors were performed in the late 1980s; cardiac transplant activities have since discontinued. In 2003, a new, national Syrian legislation was enacted authorizing the use of organs from living unrelated donors and from deceased donors. This important law was preceded by another big stride in this regard: the acceptance by the higher Islamic religious authorities in Syria in 2001 of the principle of procurement of organs from deceased donors, provided that consent is given by a first- or second-degree relative. After the enactment of this law, kidney transplant rates increased from 7 per million population in 2002 to 17 per million population in 2007. Kidney transplants performed abroad for Syrian patients declined from 25% in 2002 to < 2% in 2007. Kidney transplants continued at comparable rates until 2010, before the beginning of the political crisis in 2011. Four decades after the first successful kidney transplant in Syria, however, patients needing an organ transplant must rely on living donors only. Moreover, 17 years after the law authorizing use of organs from deceased donors, a program is still not in place in Syria, and additional improvement of the legal framework is needed. The war, limited resources, and lack of public awareness about the importance of organ donation and transplant appear to be major factors inhibiting initiation of a deceased-donor program in Syria. A concerted and ongoing education campaign is needed to increase awareness of organ donation, change negative public attitudes, and gain societal acceptance. Every effort must be made to initiate a deceased-donor program to lessen the burden on living donors and to enable national self-sufficiency in organs for transplant.

Donation after circulatory death liver transplantation: What are the limits for an acceptable DCD graft?

The utilization of donation after circulatory death (DCD) livers has been growing over the last decade. In large-volume centers, survival outcomes have improved and are comparable to outcomes with brain death donor (DBD) liver transplantation (LT). The relatively concentrated success with DCD LT demonstrated by high-volume transplant centers has rekindled international enthusiasm. The combination of increasing expertise in DCD LT and ongoing shortage in transplantable organs has promoted expansion of the DCD donor pool with regards to donor age, body mass index and donor warm ischemia time. In this review, we focused on the practice patterns in DCD liver graft utilization in the last decade, along with the possibilities for further expansion of DCD liver graft utilization and new technologies, such as machine perfusion.