What are the benefits of preemptive versus non-preemptive kidney transplantation? A systematic review and meta-analysis.

Opting for a preemptive kidney transplant (PKT) can help avoid costs and morbidity associated with dialysis. However, while multiple studies have shown clinical benefits of PKT, other studies have not demonstrated this, leading to controversy in the literature regarding the exact benefits of PKT. Therefore, this study aimed to determine the clinical outcomes of PKT versus non-preemptive kidney transplantation (nPKT) in adult patients. Multiple databases were searched up to May 4, 2022. Independent reviewers selected studies for inclusion and extracted relevant data. Risk of bias was assessed using the Downs and Black checklist. Eighty-seven studies including 859,715 adult kidney transplant patients were included the review. The risk of patient death (relative risk [95% confidence interval] 0.74 [0.60-0.91]) was significantly lower in PKT versus nPKT patients for living donor (LD) transplants, whereas the risk of overall graft loss was significantly lower in PKT compared to nPKT patients for both LD (0.72 [0.62-0.83]) as well as deceased donor (DD) transplants (0.80 [0.69-0.92]). The evidence suggests that LD PKT patients have a lower risk of patient death and graft loss compared to nPKT patients, and DD PKT patients have a lower risk of graft loss than nPKT patients.

Living Donor Kidney Transplantation in Older Individuals: An Ethical Legal and Psychological Aspects of Transplantation (ELPAT) View.

Living donor transplantation is the optimal treatment for suitable patients with end-stage kidney disease. There are particular advantages for older individuals in terms of elective surgery, timely transplantation, and early graft function. Yet, despite the superiority of living donor transplantation especially for this cohort, older patients are significantly less likely to access this treatment modality than younger age groups. However, given the changing population demographic in recent decades, there are increasing numbers of older but otherwise healthy individuals with kidney disease who could benefit from living donor transplantation. The complex reasons for this inequity of access are explored, including conscious and unconscious age-related bias by healthcare professionals, concerns relating to older living donors, ethical anxieties related to younger adults donating to aging patients, unwillingness of potential older recipients to consider living donation, and the relevant legislation. There is a legal and moral duty to consider the inequity of access to living donor transplantation, recognising both the potential disparity between chronological and physiological age in older patients, and benefits of this treatment for individuals as well as society.

Rapamycin Does Not Act as a Dietary Restriction Mimetic in the Protection against Ischemia Reperfusion Injury.

INTRODUCTION: Short-term fasting protects against renal ischemia reperfusion injury (IRI). mTOR signaling is downregulated and may be involved in its protective effect. Rapamycin is considered a possible mimetic as it inhibits the mTOR pathway. This study examines the effect of rapamycin on renal IRI. MATERIAL AND METHODS: Mice were divided into four groups: ad libitum (AL), fasted (F), AL treated with rapamycin (AL+R), and F treated with rapamycin (F+R). Rapamycin was administered intraperitoneally 24 h before bilateral renal IRI was induced. Survival was monitored for 7 days. Renal cell death, regeneration, and mTOR activity were determined 48 h after reperfusion. Oxidative stress resistance of human renal proximal tubular and human primary tubular epithelial cells after rapamycin treatment was determined. RESULTS: All F and F+R mice survived the experiment. Although rapamycin substantially downregulated mTOR activity, survival in the AL+R group was similar to AL (10%). Renal regeneration was significantly reduced in AL+R but not in F+R. After IRI (48 h), pS6K/S6K ratio was lower in F, F+R, and AL+R groups compared to AL fed animals (p = 0.02). In vitro, rapamycin also significantly downregulated mTOR activity (p < 0.001) but did not protect against oxidative stress. CONCLUSION: Rapamycin pretreatment does not protect against renal IRI. Thus, protection against renal IRI by fasting is not exclusively mediated through inhibition of mTOR activity but may involve preservation of regenerative mechanisms despite mTOR downregulation. Therefore, rapamycin cannot be used as a dietary mimetic to protect against renal IRI.

Antithrombotic Management in Adult Kidney Transplantation: A European Survey Study.

In kidney transplantation (KTx), renal graft thrombosis (RGT) is one of the main reasons for early graft loss. Although evidence-based guidance on prevention of RGT is lacking, thromboprophylaxis is widely used. The aim of this survey was to obtain a European view of the different thromboprophylactic strategies applied in KTx. An online 22-question survey, addressed to KTx professionals, was distributed by email and via platforms of the European Society for Organ Transplantation. Seventy-five responses (21 countries, 51 centers) were received: 75% had over 10 years' clinical experience, 64% were surgeons, 29% nephrologists, and 4% urologists. A written antithrombotic management protocol was available in 75% of centers. In 8 (16%) centers, respondents contradicted each other regarding the availability of a written protocol. Thromboprophylaxis is preferred by 78% of respondents, independent of existing antithrombotic management protocols. Ninety-two percent of respondents indicated that an anticipated bleeding risk is the main reason to discontinue chronic antithrombotic therapy preoperatively. Intraoperatively, 32% of respondents administer unfractionated heparin (400-10,000 international units with a median of 5,000) in selected cases. Despite an overall preference for perioperative thromboprophylaxis in KTx, there is a high variation within Europe regarding type, timing, and dosage, most likely due to the paucity of high-quality studies. Further research is warranted in order to develop better guidelines.

Ethical Issues in Kidney Transplant and Donation During COVID-19 Pandemic.

The coronavirus disease-19 pandemic caused by the severe acute respiratory syndrome coronavirus has faced the transplant community with unprecedented clinical challenges in a highly vulnerable patient category. These were associated with many uncertainties for patients and health care professionals and prompted many ethical debates regarding the safe delivery of kidney transplantation. In this article, we highlight some of the most important ethical questions that were raised during the pandemic and attempt to analyze ethical arguments in light of core principles of medical ethics to either suspend or continue kidney transplantation, and to mandate vaccination in transplant patients, transplant candidates, and, finally, health care providers. We have come up with frameworks to deal responsibly with these ethical challenges, and formulated recommendations to cope with the issues imposed on patients and transplant professionals.

Peritoneal catheter insertion: combating barriers through policy change.

Barriers to accessing home dialysis became a matter of life and death for many patients with kidney failure during the coronavirus disease 2019 (COVID-19) pandemic. Peritoneal dialysis (PD) is the more commonly used home therapy option. This article provides a comprehensive analysis of PD catheter insertion procedures as performed around the world today, barriers impacting timely access to the procedure, the impact of COVID-19 and a roadmap of potential policy solutions. To substantiate the analysis, the article includes a survey of institutions across the world, with questions designed to get a sense of the regulatory frameworks, barriers to conducting the procedure and impacts of the pandemic on capability and outcomes. Based on our research, we found that improving patient selection processes, determining and implementing correct insertion techniques, creating multidisciplinary teams, providing appropriate training and sharing decision making among stakeholders will improve access to PD catheter insertion and facilitate greater uptake of home dialysis. Additionally, on a policy level, we recommend efforts to improve the awareness and feasibility of PD among patients and the healthcare workforce, enhance and promulgate training for clinicians-both surgical and medical-to insert PD catheters and fund personnel, pathways and physical facilities for PD catheter insertion.

Prevalence of frailty and cognitive impairment in older transplant candidates - a preview to the Kidney Transplantation in Older People (KTOP): impact of frailty on outcomes study.

BACKGROUND: Kidney transplantation in older people has increased, however older transplant recipients experience mixed outcomes that invariably impacts on their quality of life. The increased vulnerability of older end stage kidney disease patients to frailty and cognitive impairment, may partially explain the differences in outcomes observed. The Kidney Transplantation in Older People (KTOP): impact of frailty on clinical outcomes study is an active clinical study aiming to explore the experience of older people waiting for and undergoing transplantation. In this manuscript we present the study protocol, the study cohort, and the prevalence of frailty and cognitive impairment identified at recruitment. METHODS: The KTOP study is a single centre, prospective, mixed methods, observational study. Recruitment began in October 2019. All patients aged 60 or above either active on the deceased donor waitlist or undergoing live donor transplantation were eligible for recruitment. Recruited participants completed a series of questionnaires assessing frailty, cognition, and quality of life, which are repeated at defined time points whilst on the waitlist and post-transplant. Clinical data was concurrently collected. Any participants identified as frail or vulnerable were also eligible for enrolment into the qualitative sub-study. RESULTS: Two hundred eight participants have been recruited (age 60-78). Baseline Montreal Cognitive Assessments were available for 173 participants, with 63 (36.4%) participants identified as having scores below normal (score < 26). Edmonton Frail Scale assessments were available for 184 participants, with 29 participants (15.8%) identified as frail (score ≥ 8), and a further 37 participants (20.1%) identified as being vulnerable (score 6-7). CONCLUSION: In the KTOP study cohort we have identified a prevalence of 36.4% of participants with MoCA scores suggestive of cognitive impairment, and a prevalence of frailty of 15.8% at recruitment. A further 20.1% were vulnerable. As formal testing for cognition and frailty is not routinely incorporated into the work up of older people across many units, the presence and significance of these conditions is likely not known. Ultimately the KTOP study will report on how these parameters evolve over time and following a transplant, and describe their impact on quality of life and clinical outcomes.

Pancreas Transplantation in Black, Asian and Minority Ethnic Patients-Single Centre Experience in the UK.

Ethnic disparities in the outcomes after simultaneous pancreas kidney (SPK) transplantation still exist. The influence of ethnicity on the outcomes of pancreas transplantation in the UK has not been reported and hence we aimed to investigate our cohort. A retrospective analysis of all pancreas transplant recipients (n = 171; Caucasians = 118/Black Asian Ethnic Minorities, BAME = 53) from 2006 to 2020 was done. The median follow-up was 80 months. Patient & pancreas graft survival, rejection rate, steroid free maintenance rate, HbA1c, weight gain, and the incidence of secondary diabetic complications post-transplant were compared between the groups. p < 0.003 was considered significant (corrected for multiple hypothesis testing). Immunosuppression consisted of alemtuzumab induction and steroid free maintenance with tacrolimus and mycophenolate mofetil. Pancreas graft & patient survival were equivalent in both the groups. BAME recipients had a higher prevalence of type-2 diabetes mellitus pre-transplant (BAME = 30.19% vs. Caucasians = 0.85%, p < 0.0001), and waited for a similar time to transplantation once waitlisted, although pre-emptive SPK transplantation rate was higher for Caucasian recipients (Caucasians = 78.5% vs. BAME = 0.85%, p < 0.0001). Despite equivalent rejections & steroid usage, BAME recipients gained more weight (BAME = 7.7% vs. Caucasians = 1.8%, p = 0.001), but had similar HbA1c (functioning grafts) at 3-,12-, 36-, and 60-months post-transplant.

Renal transplantation in gigantism: A case report.

BACKGROUND: Gigantism, characterized by excessive growth and height is due to increased secretion of growth hormone, most commonly from a pituitary adenoma. In addition to the surgical and anesthetic complexity, the extreme stature of these patients presents a unique challenge for kidney transplantation in deciding whether to proceed with a single or dual kidney transplantation. The lack of relevant literature further adds to the dilemma. CASE SUMMARY: A 45-year-old patient with untreated gigantism and end stage renal failure on renal replacement therapy was waitlisted for a deceased donor dual kidney transplantation due to the extreme physical stature (Height-247 cm and weight-200 kg). He was offered 2 kidneys from a 1-0-1 HLA mismatched 24-year-old DCD donor (Height-179 cm and weight-75 kg), and was planned for a bilateral retroperitoneal implantation into the recipient external iliac vessels. The immunosuppression consisted of alemtuzumab induction (50 mg) and steroid-free maintenance with tacrolimus. The donor's right kidney was uneventfully implanted extra-peritoneally into the right external iliac vessels. On contralateral exposure, the left common and external iliac arteries were ectatic and frail. A complex vascular reconstruction was not preferred in order to preserve the arterial supply to the left lower limb, to minimise the cold ischemia time and prevent additional warm ischemic insult to the second kidney. Hence, it was decided not to proceed with dual transplantation. Amidst concerns of nephron mass insufficiency, the graft function was remarkable with a serum creatinine of 120 µmol/L within a month from transplantation and 94 µmol/L at 1-year post transplantation, and without proteinuria. CONCLUSION: To our knowledge, this is the first case report on kidney transplantation in gigantism. Although it is believed that dual kidney transplantation is ideal, a single kidney transplantation from an appropriately selected donor can provide sufficient functioning nephron mass in patients with gigantism.

Is Preemptive Kidney Transplantation Associated With Improved Outcomes when Compared to Non-preemptive Kidney Transplantation in Children? A Systematic Review and Meta-Analysis.

Main Problem: Preemptive kidney transplantation (PKT) is performed prior to dialysis initiation to avoid dialysis-related morbidity and mortality in children and adolescents. We undertook a systematic review to compare clinical outcomes in PKT versus kidney transplantation after dialysis initiation in paediatric patients. Methods: The bibliographic search identified studies that compared paediatric recipients of a first or subsequent, living or deceased donor PKT versus non-preemptive kidney transplant. Methodological quality was assessed for all studies. Data were pooled using the random-effects model. Results: Twenty-two studies (n = 22,622) were included. PKT reduced the risk of overall graft loss (relative risk (RR) .57, 95% CI: .49-.66) and acute rejection (RR: .81, 95% CI: .75-.88) compared to transplantation after dialysis. Although no significant difference was observed in overall patient mortality, the risk of patient death was found to be significantly lower in PKT patients with living donor transplants (RR: .53, 95% CI: .34-.83). No significant difference was observed in the incidence of delayed graft function. Conclusion: Evidence from observational studies suggests that PKT is associated with a reduction in the risk of acute rejection and graft loss. Efforts should be made to promote and improve rates of PKT in this group of patients (PROSPERO). Systematic Review Registration: https://clinicaltrials.gov/, CRD42014010565.

Donor Autonomy and Self-Sacrifice in Living Organ Donation: An Ethical Legal and Psychological Aspects of Transplantation (ELPAT) View.

Clinical teams understandably wish to minimise risks to living kidney donors undergoing surgery, but are often faced with uncertainty about the extent of risk, or donors who wish to proceed despite those risks. Here we explore how these difficult decisions may be approached and consider the conflicts between autonomy and paternalism, the place of self-sacrifice and consideration of risks and benefits. Donor autonomy should be considered as in the context of the depth and strength of feeling, understanding risk and competing influences. Discussion of risks could be improved by using absolute risk, supra-regional MDMs and including the risks to the clinical team as well as the donor. The psychological effects on the donor of poor outcomes for the untransplanted recipient should also be taken into account. There is a lack of detailed data on the risks to the donor who has significant co-morbidities.

The Impact of Cold Ischaemia Time on Outcomes of Living Donor Kidney Transplantation: A Systematic Review and Meta-Analysis.

Studies have been carried out to investigate the effect of a prolonged cold ischaemia time (CIT) on the outcomes of living donor kidney transplantation (LDKT). There is no clear consensus in the literature about the effects of CIT on LDKT outcomes, and therefore, we performed a systematic review and meta-analysis to provide evidence on this subject. Searches were performed in five databases up to 12 July 2021. Articles comparing different CIT in LDKT describing delayed graft function (DGF), graft and patient survival, and acute rejection were considered for inclusion. This study is registered with PROSPERO, CRD42019131438. In total, 1452 articles were found, of which eight were finally eligible, including a total of 164,179 patients. Meta-analyses showed significantly lower incidence of DGF (odds ratio (OR) = 0.61, p < 0.01), and significantly higher 1-year graft survival (OR = 0.72, p < 0.001) and 5-year graft survival (OR = 0.88, p = 0.04), for CIT of less than 4 h. Our results underline the need to keep CIT as short as possible in LDKT (ideally < 4 h), as a shorter CIT in LDKT is associated with a statistically significant lower incidence of DGF and higher graft survival compared to a prolonged CIT. However, clinical impact seems limited, and therefore, in LDKT programmes in which the CIT might be prolonged, such as kidney exchange programmes, the benefits outweigh the risks. To minimize these risks, it is worth considering including CIT in kidney allocation algorithms and in general take precautions to protect high risk donor/recipient combinations.

Living Kidney Donor Knowledge of Provided Information and Informed Consent: The PRINCE Study.

BACKGROUND: Informed consent for living kidney donation is paramount, as donors are healthy individuals undergoing surgery for the benefit of others. The informed consent process for living kidney donors is heterogenous, and the question concerns how well they are actually informed. Knowledge assessments, before and after donor education, can form the basis for a standardized informed consent procedure for live kidney donation. METHODS: In this prospective, a multicenter national cohort study conducted in all eight kidney transplant centers in The Netherlands, we assessed the current status of the informed consent practice for live donor nephrectomy. All of the potential living kidney donors in the participating centers were invited to participate. They completed a pop quiz during their first outpatient appointment (Cohort A). Living kidney donors completed the same pop quiz upon admission for donor nephrectomy (Cohort B). RESULTS: In total, 656 pop quizzes were completed (417 in Cohort A, and 239 in Cohort B). The average donor knowledge score was 7.0/25.0 (±3.9, range 0-18) in Cohort A, and 10.5/25.0 (±2.8, range 0-17.5) in Cohort B. Cohort B scored significantly higher on overall knowledge, preparedness, and the individual item scores (p < 0.0001), except for the long-term complications (p = 0.91). CONCLUSIONS: Donor knowledge generally improves during the live donor workup, but it is still quite disappointing. Long-term complications, especially, deserve more attention during living kidney donor education.

HoloMentor: A Novel Mixed Reality Surgical Anatomy Curriculum for Robot-Assisted Radical Prostatectomy.

OBJECTIVES: The disruption to surgical training and medical education caused by the global COVID-19 pandemic highlighted the need for realistic, reliable, and engaging educational opportunities available outside of the operating theatre and accessible for trainees of all levels. This article presents the design and development of a virtual reality curriculum which simulates the surgical mentorship experience outside of the operating theatre, with a focus on surgical anatomy and surgical decision-making. METHOD: This was a multi-institutional study between London's King's College and Imperial College. The index procedure selected for the module was robotic radical prostatectomy. For each stage of the surgical procedure, subject-matter experts (N = 3) at King's College London, identified (1) the critical surgical-decision making points, (2) critical anatomical landmarks, and (3) tips and techniques for overcoming intraoperative challenges. Content validity was determined by an independent panel of subject-matter experts (N = 8) at Imperial College, London, using Fleiss' kappa statistic. The experts' teaching points were combined with operative footage and illustrative animations, and projected onto a virtual reality headset. The module was piloted to surgical science students (N = 15). Quantitative analysis compared participants' confidence regarding their anatomical knowledge before and after taking the module. Qualitative data were gathered from students regarding their views on using the virtual reality model. RESULTS: Multi-rater agreement between experts was above the 70.0% threshold for all steps of the procedure. Seventy-three percentage of pilot study participants "agreed" or "strongly agreed" that they achieved a better understanding of surgical anatomy and the rationale behind each procedural step. This was reflected in an increase in the median knowledge score after trialing the curriculum (p < 0.001). 100% of subject-matter experts and 93.3% of participants "agreed" or "strongly agreed" that virtual mentorship would be useful for future surgical training. CONCLUSIONS: This study demonstrated that virtual surgical mentorship could be a feasible and cost-effective alternative to traditional training methods with the potential to improve technical skills, such as operative proficiency and nontechnical skills such as decision-making and situational judgement.

Screening, Management, and Acceptance of Patients with Aorto-Iliac Vascular Disease for Kidney Transplantation: A Survey among 161 Transplant Surgeons.

INTRODUCTION: Aorto-iliac vascular disease (AVD) is frequently found during the workup for kidney transplantation. However, recommendations on screening and management are lacking. We aimed to assess differences in screening, management, and acceptance of these patients for transplantation by performing a survey among transplant surgeons. Second, we aimed to identify center- and surgeon-related factors associated with decline or acceptance of kidney transplant candidates with AVD. METHODS: A survey was sent to transplant surgeons and urologists. The survey contained general questions (part I) and 2 patient-based cases (part II) with Trans-Atlantic Inter-Society Consensus (TASC) D and B AVD supported with videos of their CT scans. RESULTS: One hundred ninety-one (20.3%) participants responded; 171 were currently involved in kidney transplantation: 161 (94.2%) completed part I and 145 (84.8%) part II. Screening for AVD was often (38.5%) restricted to high-risk patients. The majority of respondents (67.7%) rated "technical problems" as the most important concern in case of AVD, followed by "increased mortality risk because of cardiovascular comorbidity" (29.8%). Pretransplant vascular interventions to facilitate transplantation were infrequently performed (71.4% mentioned <10 per year). Ninety (64.3%) respondents answered that an open vascular procedure should preferably be performed prior to kidney transplantation while 42 (30.0%) respondents preferred a simultaneous open vascular procedure. The decline rate was higher in the TASC D case compared to the TASC B case (26.9% and 9.7%, respectively). Respondents from centers with expertise in pretransplant vascular interventions were more likely to accept both patients with TASC D and B for transplantation. CONCLUSION: There is no uniformity in the screening, management, and acceptance of patients with AVD for transplantation. If a center declines a patient with AVD because of technical concerns, the patient should be referred for a second opinion to a tertiary center with expertise in pretransplant vascular interventions. Multidisciplinary meetings including a vascular surgeon and a cardiologist could help optimize these patients for transplantation.

The Impact of COVID-19 on Kidney Transplant Recipients in Pre-Vaccination and Delta Strain Era: A Systematic Review and Meta-Analysis.

Herein, we performed a meta-analysis of published clinical outcomes of corona virus disease 2019 (COVID-19) in hospitalized kidney transplant recipients. A systematic database search was conducted between December 1, 2019 and April 20, 2020. We analyzed 48 studies comprising 3137 kidney transplant recipients with COVID-19. Fever (77%), cough (65%), dyspnea (48%), and gastrointestinal symptoms (28%) were predominant on hospital admission. The most common comorbidities were hypertension (83%), diabetes mellitus (34%), and cardiac disease (23%). The pooled prevalence of acute respiratory distress syndrome and acute kidney injury were 58% and 48%, respectively. Invasive ventilation and dialysis were required in 24% and 22% patients, respectively. In-hospital mortality rate was as high as 21%, and increased to over 50% for patients in intensive care unit (ICU) or requiring invasive ventilation. Risk of mortality in patients with acute respiratory distress syndrome (ARDS), on mechanical ventilation, and ICU admission was increased: OR = 19.59, OR = 3.80, and OR = 13.39, respectively. Mortality risk in the elderly was OR = 3.90; however, no such association was observed in terms of time since transplantation and gender. Fever, cough, dyspnea, and gastrointestinal symptoms were common on admission for COVID-19 in kidney transplant patients. Mortality was as high as 20% and increased to over 50% in patients in ICU and required invasive ventilation.

The Impact of Cold Ischaemia Time on Outcomes of Living Donor Kidney Transplantation in the UK Living Kidney Sharing Scheme.

OBJECTIVE: To assess the impact of CIT on living donor kidney transplantation (LDKT) outcomes in the UKLKSS versus outside the scheme. BACKGROUND: LDKT provides the best treatment option for end-stage kidney disease patients. end-stage kidney disease patients with an incompatible living donor still have an opportunity to be transplanted through Kidney Exchange Programmes (KEP). In KEPs where kidneys travel rather than donors, cold ischaemia time (CIT) can be prolonged. METHODS: Data from all UK adult LDKT between 2007 and 2018 were analysed. RESULTS: 9969 LDKT were performed during this period, of which 1396 (14%) were transplanted through the UKLKSS, which we refer to as KEP. Median CIT was significantly different for KEP versus non-KEP (339 versus 182 minutes, P < 0.001). KEP LDKT had a higher incidence of delayed graft function (DGF) (2.91% versus 5.73%, P < 0.0001), lower 1-year (estimated Glomerular Filtration Rate (eGFR) 57.90 versus 55.25 ml/min, P = 0.04) and 5-year graft function (eGFR 55.62 versus 53.09 ml/min, P = 0.01) compared to the non-KEP group, but 1- and 5-year graft survival were similar. Within KEP, a prolonged CIT was associated with more DGF (3.47% versus 1.95%, P = 0.03), and lower graft function at 1 and 5-years (eGFR = 55 vs 50 ml/min, P = 0.02), but had no impact on graft survival. CONCLUSION: Whilst CIT was longer in KEP, associated with more DGF and lower graft function, excellent 5-year graft survival similar to non-KEP was found.