KDIGO Clinical Practice Guideline on the Evaluation and Care of Living Kidney Donors

Breaking Barriers and Bridging Gaps: Advancing Diversity, Equity, and Inclusion in Kidney Transplant Care for Black and Hispanic Patients in the United States

Kidney transplantation offers better mortality and quality of life outcomes to patients with end-stage renal failure compared to dialysis. Specifically, living donor kidney transplantation is the best treatment for end-stage renal disease, since it offers the greatest survival benefit compared to deceased donor kidney transplant or dialysis. However, not all patients from all racial/ethnic backgrounds enjoy these benefits. While black and Hispanic patients bear the predominant disease burden within the United States, they represent less than half of all kidney transplants in the country. Other factors such as cultural barriers that proliferate myths about transplant, financial costs that impede altruistic donation, and even biological predispositions create a complex maze and can also perpetuate care inaccessibility. Therefore, blanket efforts to increase the overall donation pool may not extend access to vulnerable populations, who may require more targeted attention and interventions. This review uses US kidney transplantation data to substantiate accessibility differences amongst racial minorities as well as provides examples of successful institutional and national systemic level changes that have improved transplantation outcomes for all.

An evaluation of the contribution of routine ultrasound when performed with multiphase CT in renal donor imaging assessment

OBJECTIVES

We sought to examine the contribution of routine ultrasound when performed with computed tomography in identifying exclusion criteria in potential living kidney donors.

METHODS

We performed a 10-year retrospective cohort study including all cases of potential renal donors at our center. For each case, the donor workup ultrasound (US) and multiphase computed tomography (MPCT) original reports and imaging were reviewed by a fellowship-trained abdominal radiologist in consultation with a transplant urologist and placed into one of 3 groups: (1) no significant US contribution, (2) US was useful to characterize an incidental finding (either US exclusive or US aided in CT interpretation) but did not impact donor eligibility, and (3) an US exclusive finding contributed to donor exclusion.

RESULTS

A total of 432 potential live renal donors were evaluated (mean age 41, 263 women). In total, 340 (78.7%, group 1) cases had no significant US contribution. In 90 cases (20.8%, group 2), US helped to characterize one or more incidental findings but did not contribute to donor exclusion. In 1 (0.2%, group 3) case, an US exclusive finding (suspected medullary nephrocalcinosis) contributed towards donor exclusion.

CONCLUSION

US provided limited contribution to renal donor eligibility decisions when performed routinely with MPCT.

CLINICAL RELEVANCE

Routine ultrasound could potentially be omitted in the live renal donor workup, with alternative strategies including a selective approach to incorporating ultrasound and an expanded role of dual-energy CT.

KEY POINTS

• Ultrasound is performed routinely with CT for renal donor assessment in some jurisdictions; however, this practice has come into question particularly with advances in dual-energy CT. • Our study found that routine use of ultrasound provided limited contribution, primarily assisting CT in characterization of benign findings with only 1/432 (0.2%) potential donors in a 10-year period excluded based in part on an ultrasound exclusive finding. • The role of ultrasound can be narrowed to a targeted approach for certain at-risk patients, and can be further reduced if dual-energy CT is utilized.

Kidney paired donation in developing countries: A global perspective

Purpose of review

We review the key principles of kidney paired donation (KPD) and discuss the status and unique considerations for KPD in developing countries.

Recent findings

Despite the advantages of KPD programs, they remain rare among developing nations, and the programs that exist have many differences with those of in developed countries. There is a paucity of literature and lack of published data on KPD from most of the developing nations. Expanding KPD programs may require the adoption of features and innovations of successful KPD programs. Cooperation with national and international societies should be encouraged to ensure endorsement and sharing of best practices.

Summary

KPD is in the initial stages or has not yet started in the majority of the emerging nations. But the logistics and strategies required to implement KPD in developing nations differ from other parts of the world. By learning from the KPD experience in developing countries and adapting to their unique needs, it should be possible to expand access to KPD to allow more transplants to happen for patients in need world-wide.

Pegloticase efficacy and safety in kidney transplant recipients; results of the phase IV, open-label PROTECT clinical trial

INTRODUCTION

Kidney transplant (KT) recipients have a high prevalence and severity of gout. Pegloticase (pegylated recombinant uricase) rapidly metabolizes serum uric acid (sUA), and its efficacy is not impacted by kidney function.

METHODS

This open-label, Phase 4 trial (PROTECT NCT04087720) examined safety and efficacy of pegloticase in 20 participants with KT > 1 year prior to enrollment and with uncontrolled gout (sUA ≥7 mg/dL, intolerance/inefficacy to urate lowering therapy, and ≥1 of the following: tophi, chronic gouty arthritis, ≥2 flares in past year) and functioning KT (estimated glomerular filtration rate [eGFR] ≥15 mL/min/1.73 m2 ) on stable immunosuppression therapy.

RESULTS

The primary endpoint was sUA response during month 6 (sUA < 6 mg/dL for ≥80% of time). The study enrolled 20 participants (mean ± SD); age: 53.9 ± 10.9 years, time since KT: 14.7 ± 6.9 years, sUA: 9.4 ± 1.5 mg/dL, gout duration: 8.4 ± 11.6 years; all on ≥2 stable doses of immunosuppression agents. Pegloticase (8 mg intravenous every 2 weeks) in KT recipients with uncontrolled gout showed a high response rate of 89% (16/18 responders). Two participants discontinued treatment solely due to COVID-19 concerns prior to month 6 were not included in the primary analysis. Pegloticase exposures were higher than those historically observed with pegloticase monotherapy, and no anaphylaxis or infusion reaction events occurred during the study.

CONCLUSIONS

This improved response rate to pegloticase in the KT population reflects observations from other trials and reports on immunomodulation with pegloticase. As the KT population has a high prevalence of gout and limitations with oral urate lowering medication options, these findings suggest a potential option for uncontrolled gout therapy in KT participants.

A case of varicella zoster infection in kidney transplant recipient using immunosuppressant

Kidney transplant recipients must take lifelong immunosuppression to prevent acute or chronic allograft injury. However, they are also at risk for opportunistic infections due to compromised immune cell functionality. Disseminated HZ in kidney transplant recipients can result in a very high overall mortality rate of up to 30%. Here we described a 23-year-old male patient who presented to the emergency room with a complaint of high-grade fever, chills, and non-dermatomal lesion of varicella zoster skin infection that affected the face and trunk. After investigation the patient was diagnosed with chickenpox clinically and was managed with complete recovery and early hospital discharge.

Perceptions of Psychosocial and Ethical Issues and the Psychological Characteristics of Donors in the Clinical Setting of Living Kidney Donors: A Qualitative Study

BACKGROUND

There are several psychosocial and ethical issues surrounding the decision to be a living kidney donor. The present study aimed to determine the perceptions of psychosocial and ethical issues that living kidney donors may have, and analyze their psychological characteristics.

METHODS

Face-to-face semi-structured interviews were conducted with 15 donors. Thematic analysis was then performed to categorize the thematic elements of the transcripts. All procedures were approved by the relevant review board.

RESULTS

Four main categories were identified: Awareness of family dynamics, barriers to a proper understanding, contrasting psychological effects of recipient presence in clinical practice, insufficient information explained in informed consent.

CONCLUSION

Donors felt that they took on the "role as a care giver" for the recipient and were less aware of themselves as patients. This is a new concept that has not been shown in previous studies. Donors exist within the recipient and family, and the range of their autonomy may go beyond the traditional concept of autonomy and be rooted in relational autonomy. This study suggested that medical treatment in the presence of the recipient promotes the relational autonomy of the donor.

The ties that transplant: The social capital determinants of the living kidney donor relationship distribution

The network perspective on social capital decomposes it into ego's network size, alters' relevant resources, and social factors moderating access to alters' resources, but rarely examines how it is distributed across relationship types. Using this approach, I investigate the situationally-relevant social capital relationship distribution and its association with health-related social support, with an application to the living kidney donor relationship distribution. Analyzing an original survey of transplant candidates (N = 72) and their reports on their family and friends (N = 1548), I compare the tie count, donation-relevant biomedical resource, and tie strength relationship distributions to administrative data on the national distribution of living kidney donor relationships. I find that the tie strength relationship distribution matches the completed living kidney donor relationship distribution far better than the tie count and donation-relevant biomedical resource relationship distributions. These conclusions are upheld in race- and gender-stratified analyses and are robust across alternative approaches.

Progress in Pathological Diagnosis after Kidney Transplantation: Current Trend and Future Perspective

Advances in immunosuppressive therapy; posttransplant management of allograft rejection; and measures against infectious diseases, cardiovascular diseases, and malignancy dramatically improved graft and patient survival after kidney transplantation (KT). Among them, kidney allograft biopsy is an important tool and the gold standard for the diagnosis of various kidney allograft injuries, including allograft rejection, virus-induced nephropathy, calcineurin inhibitor toxicity, and posttransplant glomerular diseases. The Banff Conference on Allograft Pathology has contributed to establishing the diagnostic criteria for kidney allograft rejection and polyomavirus-associated nephropathy that are used as a common standard worldwide. In addition to the for-cause biopsy, many transplant centers perform protocol biopsies in the early and late posttransplant periods to detect and treat allograft injury earlier. Preimplantation biopsy in deceased-donor KT has also been performed, especially in the marginal donor, and attempts have been made to predict the prognosis in combination with clinical information and the renal resistance of hypothermic machine perfusion. Regarding the preimplantation biopsy from a living kidney donor, it can provide useful information on aging and/or early changes in lifestyle diseases, such as glomerulosclerosis, tubulointerstitial changes, and arterial and arteriolar sclerosis, and be used as a reference for the subsequent management of living donors. In this review, morphologic features of important kidney allograft pathology, such as allograft rejection and polyomavirus-associated nephropathy, according to the latest Banff classification and additional information derived from protocol biopsy, and future perspectives with recently developed technologies are discussed.

Long-Term Kidney and Maternal Outcomes After Pregnancy in Living Kidney Donors

For counseling it is important to know if pregnancy after Living Kidney Donation (LKD) affects long-term outcomes of the mono-kidney and the mother. Therefore, we performed a retrospective multicenter study in women ≤45 years who donated their kidney between 1981 and 2017. Data was collected via questionnaires and medical records. eGFR of women with post-LKD pregnancies were compared to women with pre-LKD pregnancies or nulliparous. eGFR before and after pregnancy were compared in women with post-LKD pregnancies. Pregnancy outcomes post-LKD were compared with pre-LKD pregnancy outcomes. 234 women (499 pregnancies) were included, of which 20 with pre- and post-LKD pregnancies (68) and 26 with only post-LKD pregnancies (59). Multilevel analysis demonstrated that eGFR was not different between women with and without post-LKD pregnancies (p = 0.23). Furthermore, eGFR was not different before and after post-LKD pregnancy (p = 0.13). More hypertensive disorders of pregnancy (HDP) occurred in post-LKD pregnancies (p = 0.002). Adverse fetal outcomes did not differ. We conclude that, despite a higher incidence of HDP, eGFR was not affected by post-LKD pregnancy. In line with previous studies, we found an increased risk for HDP after LKD without affecting fetal outcome. Therefore, a pregnancy wish alone should not be a reason to exclude women for LKD.

A Conceptual Framework for Evaluating National Organ Donation and Transplantation Programs

Conceptual frameworks are valuable resources that can be used to guide the planning, evaluation, and development of healthcare services. However, there are currently no comprehensive frameworks focused on organ donation and transplantation that identify the critical factors underlying a successful national program. To address this knowledge gap, we developed a conceptual framework that takes into account all major domains of influence, including political and societal aspects as well as clinical implementation. The framework was initially constructed based on a targeted review of the relevant medical literature. Feedback provided by a panel of international experts was incorporated into the framework via an iterative process. The final framework features 16 essential domains that are critical for initiating and maintaining a successful program and improving the health of patients with organ failure. Of particular note, these domains are subject to three overarching health system principles: responsiveness, efficiency, and equity. This framework represents a first attempt to develop a whole-system view of the various factors that contribute to the success of a national program. These findings provide a useful tool that can be adapted to any jurisdiction and used to plan, evaluate, and improve organ donation and transplantation programs.

Implementation of a culturally competent APOL1 genetic testing programme into living donor evaluation: A two-site, non-randomised, pre-post trial design

INTRODUCTION

While living donor (LD) kidney transplantation is the optimal treatment for patients with kidney failure, LDs assume a higher risk of future kidney failure themselves. LDs of African ancestry have an even greater risk of kidney failure post-donation than White LDs. Because evidence suggests that Apolipoprotein L1 (APOL1) risk variants contribute to this greater risk, transplant nephrologists are increasingly using APOL1 genetic testing to evaluate LD candidates of African ancestry. However, nephrologists do not consistently perform genetic counselling with LD candidates about APOL1 due to a lack of knowledge and skill in counselling. Without proper counselling, APOL1 testing will magnify LD candidates' decisional conflict about donating, jeopardising their informed consent. Given cultural concerns about genetic testing among people of African ancestry, protecting LD candidates' safety is essential to improve informed decisions about donating. Clinical 'chatbots', mobile apps that provide genetic information to patients, can improve informed treatment decisions. No chatbot on APOL1 is available and no nephrologist training programmes are available to provide culturally competent counselling to LDs about APOL1. Given the shortage of genetic counsellors, increasing nephrologists' genetic literacy is critical to integrating genetic testing into practice.

METHODS AND ANALYSIS

Using a non-randomised, pre-post trial design in two transplant centres (Chicago, IL, and Washington, DC), we will evaluate the effectiveness of culturally competent APOL1 testing, chatbot and counselling on LD candidates' decisional conflict about donating, preparedness for decision-making, willingness to donate and satisfaction with informed consent and longitudinally evaluate the implementation of this intervention into clinical practice using the Reach, Effectiveness, Adoption, Implementation and Maintenance framework.

ETHICS AND DISSEMINATION

This study will create a model for APOL1 testing of LDs of African ancestry, which can be implemented nationally via implementation science approaches. APOL1 will serve as a model for integrating culturally competent genetic testing into transplant and other practices to improve informed consent. This study involves human participants and was approved by Northwestern University IRB (STU00214038). Participants gave informed consent to participate in the study before taking part.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04910867. Registered 8 May 2021, https://register.

CLINICALTRIALS

gov/prs/app/action/SelectProtocol?sid=S000AWZ6&selectaction=Edit&uid=U0001PPF&ts=7&cx=-8jv7m2 ClinicalTrials.gov Identifier: NCT04999436. Registered 5 November 2021, https://register.

CLINICALTRIALS

gov/prs/app/action/SelectProtocol?sid=S000AYWW&selectaction=Edit&uid=U0001PPF&ts=11&cx=9tny7v.

The Minnesota attributable risk of kidney donation (MARKD) study: a retrospective cohort study of long-term (> 50 year) outcomes after kidney donation compared to well-matched healthy controls

BACKGROUND

There is uncertainty about the long-term risks of living kidney donation. Well-designed studies with controls well-matched on risk factors for kidney disease are needed to understand the attributable risks of kidney donation.

METHODS

The goal of the Minnesota Attributable Risk of Kidney Donation (MARKD) study is to compare the long-term (> 50 years) outcomes of living donors (LDs) to contemporary and geographically similar controls that are well-matched on health status. University of Minnesota (n = 4022; 1st transplant: 1963) and Mayo Clinic LDs (n = 3035; 1st transplant: 1963) will be matched to Rochester Epidemiology Project (REP) controls (approximately 4 controls to 1 donor) on the basis of age, sex, and race/ethnicity. The REP controls are a well-defined population, with detailed medical record data linked between all providers in Olmsted and surrounding counties, that come from the same geographic region and era (early 1960s to present) as the donors. Controls will be carefully selected to have health status acceptable for donation on the index date (date their matched donor donated). Further refinement of the control group will include confirmed kidney health (e.g., normal serum creatinine and/or no proteinuria) and matching (on index date) of body mass index, smoking history, family history of chronic kidney disease, and blood pressure. Outcomes will be ascertained from national registries (National Death Index and United States Renal Data System) and a new survey administered to both donors and controls; the data will be supplemented by prior surveys and medical record review of donors and REP controls. The outcomes to be compared are all-cause mortality, end-stage kidney disease, cardiovascular disease and mortality, estimated glomerular filtration rate (eGFR) trajectory and chronic kidney disease, pregnancy risks, and development of diseases that frequently lead to chronic kidney disease (e.g. hypertension, diabetes, and obesity). We will additionally evaluate whether the risk of donation differs based on baseline characteristics.

DISCUSSION

Our study will provide a comprehensive assessment of long-term living donor risk to inform candidate living donors, and to inform the follow-up and care of current living donors.

Τhe Impact of Pre-Transplant Kidney Biopsy on the Evaluation of Prospective Living Kidney Donors

Living kidney donation contributes to increasing the donor pool. Since safety and excellent outcomes of living kidney donors (LKD) are essential, renal biopsy must be part of the pre-transplant evaluation in donors with isolated urine abnormalities or other risk factors. We retrospectively collected data on potential living donors evaluated in the pre-transplant outpatient clinic of Laiko General Hospital of Athens between 2007 and 2022, who underwent a pre-transplant biopsy. Biopsy indications included microscopic hematuria, borderline proteinuria and comorbidities suggestive of chronicity. Those with glomerular diseases or chronic lesions were excluded from donation. We identified 59 potential living donors who underwent renal biopsy. Of these, 10 (16.9%) were male. Median age was 58 (IQR 51-63) years, while 23 (39%) were older than 60 years. 49 out of 59 (83%) had glomerular hematuria, 10 (16.7%) had proteinuria (150-300 mg/d). Out of the 59 donors, 21 (35.6%) were hypertensive, three (5.1%) had impaired glucose tolerance and seven (11.9%) had a BMI > 30 kg/m². A total of 32 (54.2%) potential donors were accepted for donation. Eight (13.6%) had IgA nephropathy, 10 (16.9%) TBMD and nine (15.3%) had increased chronicity including secondary FSGS. When compared with a control group of donors who did not need a pre-transplant biopsy, those 32 who donated were more frequently hypertensive (p = 0.003), but had similar eGFR [61.3 (±10.4) vs. 61.9 (±13.8), p = 0.866] after a follow-up of 79 (36-114) months. Renal biopsy is a useful tool in the evaluation of prospective LKD. Thorough assessment of donors with isolated urine abnormalities and marginal donors is critical to ensure good post-donation outcomes.

The Impact of Antiviral Treatment of Hepatitis B Virus after Kidney Transplant and the Latest Insights

BACKGROUND

The current frequency of hepatitis B virus infection in patients with advanced chronic kidney disease (CKD) (including patients on maintenance dialysis and kidney transplant recipients) is low but not negligible worldwide. HBV has a deleterious effect on survival after a kidney transplant; antiviral treatments improved the short-term outcomes of kidney transplant recipients, but their long-term impact remains uncertain.

AIM

The aim of this review is to assess the role of antiviral therapy for HBV in improving survival after a kidney transplant. The recent publication of large surveys has prompted us to update the available evidence on the impact of HBV on patient and graft survival after a kidney transplant.

METHODS

We have conducted an extensive review of the medical literature, and various research engines have been used.

RESULTS

We retrieved several studies (n = 11; n = 121,436 unique patients) and found an association between positive serologic HBsAg status and diminished patient and graft survival after a kidney transplant; the adjusted relative risk (aRR) of all-cause mortality and graft loss was 2.85 (95% CI, 2.36; 3.33, p < 0.0001) and 1.26 (95% CI, 1.02; 1.51, p < 0.0001), respectively. To our knowledge, at least six studies reported improved patient and graft survival after the adoption of antiviral therapies for HBV (this result was reported with both survival curves and multivariable regression). According to novel clinical guidelines, entecavir has been suggested as a 'first line' antiviral agent for the treatment of HBV after a kidney transplant.

CONCLUSIONS

The recent availability of safe and effective antiviral drugs for the treatment of HBV has meant that the survival curves of HBsAg-positive patients on antiviral therapy and HBsAg-negative patients after a kidney transplant can be comparable. Antiviral therapy should be systematically proposed to HBV-positive kidney transplant recipients and candidates to avoid the deleterious hepatic and extra-hepatic effects of chronic HBV replication.

Estimation of differential renal function on routine abdominal imaging employing compressed-sensed contrast-enhanced MR: a feasibility study referenced against dynamic renal scintigraphy in patients with deteriorating renal retention parameters

PURPOSE

To assess whether high temporal/spatial resolution GRASP MRI acquired during routine clinical imaging can identify several degrees of renal function impairment referenced against renal dynamic scintigraphy.

METHODS

This retrospective study consists of method development and method verification parts. During method development, patients subject to renal imaging using gadoterate meglumine and GRASP post-contrast MRI technique (TR/TE 3.3/1.6 ms; FoV320 × 320 mm; FA12°; Voxel1.1 × 1.1x2.5 mm) were matched into four equally-sized renal function groups (no-mild-moderate-severe impairment) according to their laboratory-determined estimated glomerular filtration rates (eGFR); 60|120 patients|kidneys were included. Regions-of-interest (ROIs) were placed on cortices, medullary pyramids and collecting systems of bilateral kidneys. Cortical perfusion, tubular concentration and collecting system excretion were determined as Time_{Cortex=Pyramid}(sec), Slope_Tubuli (sec^-1), and Time_{Collecting System} (sec), respectively, and were measured by a combination of extraction of time intensity curves and respective quantitative parameters. For method verification, patients subject to GRASP MRI and renal dynamic scintigraphy (99mTc-MAG3, 100 MBq/patient) were matched into three renal function groups (no-mild/moderate-severe impairment). Split renal function parameters post 1.5-2.5 min as well as MAG3 TER were correlated with time intensity parameters retrieved using GRASP technique; 15|30 patients|kidneys were included.

RESULTS

Method development showed differing values for Time_{Cortex=Pyramid}(71|75|93|122 s), Slope_Tubuli(2.6|2.1|1.3|0.5 s^-1) and Time_{Collecting System}(90|111|129|139 s) for the four renal function groups with partial significant tendencies (several p-values <  0.001). In method verification, 29/30 kidneys (96.7%) were assigned to the correct renal function group.

CONCLUSION

High temporal and spatial resolution GRASP MR imaging allows to identify several degrees of renal function impairment using routine clinical imaging with a high degree of accuracy.

Newly Diagnosed Monostotic Paget's Disease of Bone during Living Kidney Donor Candidate Evaluation

The popularity of living-donor organ donation has increased recently as an alternative to deceased-organ donation due to the growing need for organs and a shortage of deceased-donor organs. This procedure requires an in-depth health assessment of candidates, who must be in excellent physical and mental health. We present a potential living-kidney donor withdrawn from donation due to a newly diagnosed Paget's disease of bone (PDB). The patient underwent computed tomography (CT), magnetic resonance imaging (MRI), bone scintigraphy, and bone densitometry with trabecular bone score (TBS) assessment. The sole lumbar vertebra affected by PDB was investigated comprehensively, non-invasively, quantitatively, and qualitatively.

Long-Term Outcomes for Living Kidney Donors With Early Guideline-Concordant Follow-up Care: A Retrospective Cohort Study

Background

Current guidelines recommend that living kidney donors receive lifelong annual follow-up care to monitor kidney health. In the United States, the reporting of complete clinical and laboratory data for kidney donors has been mandated for the first 2 years post-donation; however, the long-term impact of early guideline-concordant care remains unclear.

Objective

The primary objective of this study was to compare long-term post-donation follow-up care and clinical outcomes of living kidney donors with and without early guideline-concordant follow-up care.

Design

Retrospective, population-based cohort study.

Setting

Linked health care databases were used to identify kidney donors in Alberta, Canada.

Patients

Four hundred sixty living kidney donors who underwent nephrectomy between 2002 and 2013.

Measurements

The primary outcome was continued annual follow-up at 5 and 10 years (adjusted odds ratio with 95% confidence interval, _LCLaOR_UCL). Secondary outcomes included mean change in estimated glomerular filtration rate (eGFR) over time and rates of all-cause hospitalization.

Methods

We compared long-term follow-up and clinical outcomes for donors with and without early guideline-concordant care, defined as annual physician visit and serum creatinine and albuminuria measurement for the first 2 years post-donation.

Results

Of the 460 donors included in this study, 187 (41%) had clinical and laboratory evidence of guideline-concordant follow-up care throughout the first 2 years post-donation. The odds of receiving annual follow-up for donors without early guideline-concordant care were 76% lower at 5 years (aOR _0.180.24_0.32) and 68% lower at 10 years (aOR _0.230.32_0.46) compared with donors with early care. The odds of continuing follow-up remained stable over time for both groups. Early guideline-concordant follow-up care did not appear to substantially influence eGFR or hospitalization rates over the longer term.

Limitations

We were unable to confirm whether the lack of physician visits or laboratory data in certain donors was due to physician or patient decisions.

Conclusions

Although policies directed toward improving early donor follow-up may encourage continued follow-up, additional strategies may be necessary to mitigate long-term donor risks.

Pregnancy outcomes after living kidney donation from a nationwide population-based cohort study from Korea

While most living kidney donors experience good outcomes and high rates of satisfaction, kidney donation can increase the risk of gestational hypertension or preeclampsia. However, pregnancy outcomes in non-white donors are limited. We conducted a nationwide cohort study of 112 living kidney donors and 672 matched healthy non-donors using the Korean National Health Insurance Claims Database. Donors and healthy non-donors were matched according to age, year of cohort entry, residency, income, number of pregnancies, and the time to the first pregnancy after cohort entry. We assessed pregnancy outcomes of live kidney donors compared with matched healthy non-donors using the nationwide database. Gestational hypertension or preeclampsia was more common in kidney donors than in non-donors (8.9% vs. 1.8%; adjusted odds ratio, 2.68; 95% confidence interval, 1.11-6.50). However, the incidence of severe gestational hypertension or preeclampsia that required antihypertensive medication was comparable (2.7% vs. 0.9%; P = 0.121). The time from donation to delivery within 5 years and primiparity were risk factors for preeclampsia in donors. Low birth weight, stillbirth, and ectopic pregnancy were not significantly different between the two groups. Maternal death occurred in two non-donor cases, but none occurred in donors compared to non-donors. Our findings indicate that kidney donors are associated with an increased risk of gestational hypertension or preeclampsia than matched healthy non-donors. However, the probabilities of serious maternal and fetal outcomes remained low and are not increased significantly after kidney donation.

Kidney function, cardiovascular outcomes and survival of living kidney donors with hypertension: a systematic review protocol

INTRODUCTION

Hypertension has been considered a contraindication for living kidney donation in the past. Since transplantation from living kidney donors remains the best modality for kidney failure, there is now an increased acceptance of living kidney donors with hypertension. However, the safety of this practice for the cardiovascular and kidney health of the donor is unclear. We will conduct a systematic review to summarise and synthesise the existing literature on this topic.

METHODS AND ANALYSIS

A systematic review of prospective randomised and non-randomised and retrospective studies will be conducted. MEDLINE, EMBASE, Cochrane CENTRAL and EBM reviews published from January 1946 to December 2021 will be reviewed. Primary outcome will be the difference in the survival, major adverse cardiovascular events, estimated glomerular filtration rate of 45 mL/min or less and development of end-stage kidney failure, between living kidney donors with and without hypertension. Study screening, selection, and data extraction will be performed by two independent reviewers. Studies must fulfil all eligibility criteria for inclusion into the systematic review and meta-analysis. The Risk of Bias in Non-Randomised studies tool will be used to assess bias.

ETHICS AND DISSEMINATION

No ethical approval is required for this systematic review. The results of this review will be disseminated in a peer-reviewed, open-access journal to ensure access to all stakeholders in kidney transplantation and to inform clinical guidelines on the evaluation and follow-up care of living kidney donor candidates.

PROSPERO REGISTRATION NUMBER

CRD42022300119.

Precision medicine implementation challenges for APOL1 testing in chronic kidney disease in admixed populations

Chronic Kidney Disease (CKD) is a public health problem that presents genetic and environmental risk factors. Two alleles in the Apolipoprotein L1 (APOL1) gene were associated with chronic kidney disease; these alleles are common in individuals of African ancestry but rare in European descendants. Genomic studies on Afro-Americans have indicated a higher prevalence and severity of chronic kidney disease in people of African ancestry when compared to other ethnic groups. However, estimates in low- and middle-income countries are still limited. Precision medicine approaches could improve clinical outcomes in carriers of risk alleles in the Apolipoprotein L1 gene through early diagnosis and specific therapies. Nevertheless, to enhance the definition of studies on these variants, it would be necessary to include individuals with different ancestry profiles in the sample, such as Latinos, African Americans, and Indigenous peoples. There is evidence that measuring genetic ancestry improves clinical care for admixed people. For chronic kidney disease, this knowledge could help establish public health strategies for monitoring patients and understanding the impact of the Apolipoprotein L1 genetic variants in admixed populations. Therefore, researchers need to develop resources, methodologies, and incentives for vulnerable and disadvantaged communities, to develop and implement precision medicine strategies and contribute to consolidating diversity in science and precision medicine in clinical practice.

Volumetric microsampling for simultaneous remote immunosuppressant and kidney function monitoring in outpatient kidney transplant recipients

AIMS

Immunosuppressant and kidney function monitoring are crucial for kidney transplant recipient follow-up. Microsamples enable remote sampling and minimise patient burden as compared to conventional venous sampling at the clinic. We developed a liquid chromatography-tandem mass spectrometry assay to quantify tacrolimus, mycophenolic acid (MPA), creatinine and iohexol in dried blood spot (DBS), and volumetric absorptive microsample (VAMS) samples.

METHODS

The assay was successfully validated analytically for all analytes. Clinical validation was conducted by direct comparison of paired DBS, VAMS and venous reference samples from 25 kidney transplant recipients. Patients received iohexol 5-15 minutes before immunosuppressant intake and were sampled 0, 1, 2 and 3 hours thereafter, enabling tacrolimus and MPA area under the concentration-time curve (AUC) and creatinine-based and iohexol-based glomerular filtration rate (GFR) estimation. Method agreement was evaluated using Passing-Bablok regression, Bland-Altman analysis and the percentages of values within 15-30% of the reference (P15 -P30 ) with a P20 acceptance threshold of 80%.

RESULTS

For DBS samples, method agreement was excellent for tacrolimus trough concentrations (n = 25, P15  = 92.0%) and AUCs (n = 25; P20  = 95.8%) and adequate for creatinine-based GFR trend monitoring (n = 25; P20  = 80%). DBS-based MPA AUC assessment showed suboptimal agreement (n = 16; P20  = 68.8%), but was considered acceptable given its P30 of 100%. The assay performed inadequately for DBS-based iohexol GFR determination (n = 24; P20  = 75%). The VAMS technique generally showed inferior performance, but can be considered for certain situations.

CONCLUSION

The assay was successfully validated for tacrolimus, MPA and creatinine quantification in DBS samples, enabling simultaneous remote kidney function trend monitoring and immunosuppressant therapeutic drug monitoring in kidney transplant recipients.

Microscopic Hematuria at Kidney Donor Screening and Post-Donation Kidney Outcomes

Although guidelines recommend a kidney biopsy in prospective living kidney donors with unexplained microscopic hematuria, individuals with mild hematuria are commonly allowed to donate without a biopsy. However, the prognostic implications of pre-donation hematuria are unclear. We investigated whether pre-donation microscopic hematuria is associated with changes in post-donation eGFR, proteinuria, or blood pressure. We included 701 living kidney donors with two pre-donation urinalyses and post-donation annual evaluations of the estimated glomerular filtration rate (eGFR), protein/creatinine ratio (PCR), and systolic blood pressure (SBP). The association between pre-donation microscopic hematuria and outcomes was assessed using generalized linear mixed models. The median [interquartile range] follow-up was 5 (2-8) years. Eighty-eight donors had pre-donation microscopic hematuria. There were no significant associations between microscopic hematuria at screening and the course of eGFR (0.44 mL/min/1.73 m2 increase/year for hematuria donors vs. 0.34 mL/min/1.73 m2 increase/year for non-hematuria donors (p = 0.65)), PCR (0.02 vs. 0.04 mg/mmol increase/year, p = 0.38), or SBP (1.42 vs. 0.92 mmHg increase/year, p = 0.17) post-donation, even after adjusting for potential confounders. Additional analyses in high-risk subgroups yielded similar results. In this study, pre-donation microscopic hematuria was not associated with post-donation eGFR decline, proteinuria, or hypertension. Microscopic hematuria may reflect primary kidney disease in only a limited subset of donors. Future studies should identify high-risk donor profiles that require further investigation.

Insufficient early renal recovery and progression to subsequent chronic kidney disease in living kidney donors

BACKGROUND/AIMS

Renal recovery of a kidney donor after undergoing nephrectomy though challenging is essential. We aimed to examine the effect of estimated glomerular filtration rate (eGFR) percent change at 1-month post-donation on insufficient kidney function after kidney donation.

METHODS

A total of 3,952 living kidney donors who underwent donor nephrectomy from 1982 to 2019 from eight different tertiary hospitals in Korea were initially screened. Percent changes in the eGFR from baseline to 1-month post-donation were calculated. The degree of percent changes was categorized by quartile, and the 1st quartile was regarded as the group with the lowest decreased eGFR at 1-month after donation. The remaining eGFR less than 60 mL/min/1.73 m2 was the end-point. The Cox proportional hazard model was used for evaluating the impact of initial eGFR and eGFR percent change at 1-month post-donation on the condition with remaining eGFR &lt; 60 mL/ min/1.73 m2. In the multivariate analysis, we used variables with a p &lt; 0.1 in the univariate analysis.

RESULTS

A total of 1,585 donors were included in the analysis. During 62.2 ± 49.3 months, 13.7% of donors showed renal insufficiency. The 4th (adjusted hazard ratio [aHR], 10.41; 95% confidence interval [CI], 5.15 to 21.04) and the 3rd (aHR, 4.29; 95% CI, 2.15 to 8.56) quartiles of percent change in eGFR and the pre-donation eGFR (aHR, 0.90; 95% CI, 0.88 to 0.92) were associated with the development of renal insufficiency.

CONCLUSION

The impact of worse initial renal recovery on renal insufficiency was pronounced in donors with lower pre-donation eGFRs. Additionally, worse initial renal recovery of remaining kidney affected the long-term development of renal insufficiency in kidney donors.

Approach to genetic testing to optimize the safety of living donor transplantation in Alport syndrome spectrum

Alport syndrome spectrum can be considered as a group of genetic diseases affecting the major basement membrane collagen type IV network in various organs including the ear, eye, and kidney. The living donor candidate evaluation is an ever-changing landscape. Recently, next-generation sequence (NGS) panels have become readily available and provide opportunities to genetically screen recipient and donor candidates for collagen network gene variants. In this review, our aim is to provide a comprehensive update on the role of genetic testing for the evaluation of potential living kidney donors to kidney candidates with Alport syndrome spectrum. We examine the utility of genetic testing in the evaluation of potential donors for recipients with Alport syndrome spectrum, and discuss risks and unresolved challenges. Suggested algorithms in the context of related and unrelated donation are offered. In contemporary practice, an approach to the evaluation of living donor candidates for transplant candidates with Alport syndrome spectrum can incorporate genetic testing in algorithms tailored for donor-recipient relationship status. Ongoing research is needed to inform optimal practice.

Psychosocial and Ethical Behaviors and Attitudes of Health Care Professionals in the Clinical Setting of Living Kidney Donors: A Qualitative Study

BACKGROUND

There are several psychosocial and ethical issues surrounding the decision making of living kidney transplant donors. This study aimed to determine what health care professionals (HPs) consider in their clinical practice and their attitudes toward donors' decision-making processes.

METHODS

Face-to-face semistructured interviews were conducted with 15 HPs. A thematic analysis was performed to categorize the thematic elements of the transcripts. All procedures were approved by the relevant review board and conducted in accordance with the Declaration of Helsinki.

RESULTS

Six main categories-maintaining family relationships, improving donor understanding, supporting voluntary decision making, setting the environment for the examination, having different attitudes toward the donor's intentions, and resisting confirmation of intent-were identified. The HPs provided diverse considerations to respect the donors' autonomy.

CONCLUSION

In clinical practice, there is a lack of practical methods to confirm living donors' levels of understanding and spontaneity, suggesting that these methods need to be established. Factors related to family functioning may reflect the unique culture of Japan, and this may be indicative of the need to consider treatment based on cultural values.

Cancer risk in living kidney donors

Living kidney donors are screened for transmissible diseases including cancer. Outcomes following donation are excellent, but concern exists regarding development of chronic kidney disease, and cancer risk is unknown. We used linked transplant and cancer registry data to identify incident cancers among 84,357 kidney donors in the United States (1995-2017). We compared risk with the general population using standardized incidence ratios (SIRs). For selected cancers, we used Poisson regression to compare donors with 47,451 Adventist Health Study 2 (AHS-2) participants, who typically have healthy lifestyles. During follow-up, 2843 cancers were diagnosed in donors, representing an overall deficit (SIR 0.79, 95%CI 0.76-0.82). None of 46 specified cancer sites occurred in excess relative to the general population, and 15 showed significant deficits (SIR < 1.00). Compared with AHS-2 participants, donors had similar incidence of liver cancer, melanoma, breast cancer, and non-Hodgkin lymphoma but, starting 7 years after donation, elevated incidence of colorectal cancer (adjusted incidence rate ratio 2.07, 95%CI 1.54-2.79) and kidney cancer (2.97, 1.58-5.58, accounting for the presence of a single kidney in donors). Elevated kidney cancer incidence may reflect adverse processes in donors' remaining kidney. Nonetheless, cancer risk is lower than in the general population, suggesting that enhanced screening is unnecessary.

Living Kidney Donation: Glomerular Filtration Rate-Based Donor Selection Criteria

Despite different guidelines and recommendations for evaluating the renal function of living kidney donors, there is still no consensus about the best approach. It is uncertain whether to have measured glomerular filtration rate, estimated it, or both. The absolute value, body surface area-dependent, and age-specified estimated glomerular filtration rates have not been consistent across different populations and practices. The increasing demand for donors has mandated clear selection criteria for glomerular filtration rate. Thus, the next big question is how low should the glomerular filtration be? Indeed, a low level would preclude the misclassification of donors and mitigate future donor risks of chronic kidney disease. The recent consensus on removing factors on race and ethnicity in the estimated glomerular filtration rate equations added a new perspective to the concept of donor assessment of glomerular filtration rate. Furthermore, the increasing use of point of care devices to assess creatinine and estimated glomerular filtration rate will be a paradigm shift in the practice of nephrology. These challenges and updates make glomerular filtration rate-based donor selection criteria an always timely topic in living kidney donation.

A parallel evaluation of short- and mid-term changes of ambulatory blood pressure in kidney transplant recipients and kidney donors

Introduction

Kidney transplantation (KTx) is associated with improved blood pressure (BP) levels for kidney transplant recipients (KTRs) without evoking significant changes in donors. However, there is a paucity of studies offering simultaneous detailed evaluation of BP profiles over time in transplant donor-recipient pairs. The aim of the present study was the parallel evaluation of ambulatory BP levels and trajectories in KTRs and their respective living kidney donors in the short and mid-term following KTx.

Methods

The study enrolled 40 prospective adult KTRs and their 40 respective donors. All participants were evaluated with 24-h ambulatory BP monitoring (Mobil-O-Graph NG device) at three time points: baseline (1 month before KTx), 3 months and 12 months after KTx.

Results

In KTRs, 3-month 24-h systolic BP (SBP) was marginally reduced and 12-month 24-h SBP significantly reduced compared with baseline [131.9 ± 13.3 versus 126.4 ± 11.9 mmHg (P = .075) and 123.9 ± 10.3 mmHg (P = .009),  respectively]. At both the 3- and 12-month time points, 24-h diastolic BP (DBP) was significantly reduced [86.7 ± 11.5 versus 82.2 ± 8.1 mmHg (P = .043) and 80.3 ± 8.5 mmHg (P = .009)]. Similar observations were made for day- and night time SBP and DBP. Repeated-measures analysis of variance (ANOVA) showed a significant gradual decrease over time in mean 24-h SBP [F(1.463, 39.505) = 3.616; P = .049, partial η ² = 0.118] and DBP [F(1.374, 37.089) = 11.34; P = .055, partial η ² = 0.116]. In contrast, in kidney donors, 24-h SBP [118.5 ± 11.6 versus 118.2 ± 12.8 mmHg (P = .626) and 119.2 ± 11.4 mmHg (P = .748)] and DBP did not change at 3 or 12 months compared with baseline; repeated measures ANOVA showed no differences in the mean 24-h SBP and DBP levels over time. The number of antihypertensive agents decreas in KTRs and remained stable in donors.

Conclusions

KTx reduces ambulatory BP levels and trajectories in KTRs at 3 months and further so at 12 months post-surgery. Kidney donation does not affect the ambulatory BP levels and trajectories of donors at the same intervals.

Necesidades asistenciales en el estudio de personas candidatas a donantes de riñón

Objetivos: Describir las necesidades asistenciales del candidato a donante de riñón; sus características sociodemográficas y clínicas; y analizar los resultados desde una perspectiva de género.Material y Método: Estudio observacional descriptivo transversal. Se recogieron datos clínicos; sociodemográficos; y el número y tipo de visitas y pruebas realizadas durante el año 2020.Resultados: Se incluyeron 60 candidatos a donantes de riñón (n=37 mujeres; 61,67%) con una media de 51,98±14,50 años y una mediana de 2,5 [RIQ (0,69-5,29)] meses de estudio. 16 (26,67%) fueron aptos para la donación, correspondiendo al 14,16% de la actividad en Trasplante Renal (TR) del centro de referencia. Se requirieron 757 visitas (20,60% de la actividad) de las que 341 (45,05%) fueron visitas con la enfermera. Se requirieron 423 pruebas (19,60% de la actividad) durante el estudio. Se identificó una media de 1,87±1,35 factores de riesgo cardiovascular en la muestra analizada, siendo de 1,56±0,81 en los que finalmente fueron donantes. Más mujeres (n=12; 75%) que hombres (n=4; 25%) fueron finalmente donantes renales.Conclusiones: El estudio del candidato a donante de riñón es complejo e implica el doble de actividad que en el de los candidatos a receptores de trasplante renal. El proceso finaliza en donación en el 27% de los candidatos estudiados. La enfermera concentra el 45% de las visitas que se requieren. Es necesario explorar estrategias para optimizar el proceso de estudio. Hay diferencias de género en cuanto a la predisposición para estudiarse voluntariamente como candidata a donante renal.

Renal hypouricemia in a recipient of living-donor kidney transplantation: a case report and literature review

Hypouricemia in kidney transplant (KT) recipients is rare since they usually have subnormal kidney function which raises serum uric acid level. Recently, interests in pathogenesis of hypouricemia have been increasing due to the understanding of the role of uric acid transporter in renal hypouricemia (RHUC). We herein report the case of RHUC consequently developed in a KT recipient from a living donor with RHUC diagnosed by the detailed urinary and genetic test. A 73-year-old Japanese man underwent KT, and the donor was his wife who had hypouricemia [serum uric acid (S-UA) 0.6 mg/dL]. Nine months after KT, the recipient's S-UA was low (1.5 mg/dL) with serum creatinine (S-Cr) of 1.56 mg/dL, and fractional excretion of UA (FEUA) was high (59.7%; normal < 10%), indicating RHUC. Regarding the donor's information, S-Cr, S-UA, and FEUA were 0.95 mg/dL, 1.0 mg/dL, and 54.5%, respectively. To investigate further on the pathogenesis of RHUC in both the recipient and the donor, we performed genetic tests. The donor had a homozygous mutation of W258X in the SLC22A12 gene and the recipient had a wild type of W258X. Finally, we reviewed the previous literature on RHUC among KT recipients and discussed the strategy of follow-up for these patients.

Comparison of CT volumetry versus nuclear renography for predicting remaining kidney function after uninephrectomy in living kidney donors

Computed tomography (CT) and nuclear renography are used to determine kidney procurement in living kidney donors (LKDs). The present study investigated which modality better predicts kidney function after donation. This study included 835 LKDs and they were divided into two subgroups based on whether the left–right dominance of kidney volume was concordant with kidney function (concordant group) or not (discordant group). The predictive value for post-donation kidney function between the two imaging modalities was compared at 1 month, 6 months, and > 1 year in total cohort, concordant, and discordant groups. Split kidney function (SKF) measured by both modalities showed significant correlation with each other at baseline. SKFs of remaining kidney measured using both modalities before donation showed significant correlation with eGFR (estimated glomerular filtration rate) after donation in the total cohort group and two subgroups, respectively. CT volumetry was superior to nuclear renography for predicting post-donation kidney function in the total cohort group and both subgroups. In the discordant subgroup, a higher tendency of kidney function recovery was observed when kidney procurement was determined based on CT volumetry. In conclusion, CT volumetry is preferred when determining procurement strategy especially when discordance is found between the two imaging modalities.

Evaluation of Genetic Kidney Diseases in Living Donor Kidney Transplantation: Towards Precision Genomic Medicine in Donor Risk Assessment

Purpose of Review

To provide a comprehensive update on the role of genetic testing for the evaluation of kidney transplant recipient and living donor candidates.

Recent Findings

The evaluation of candidates for living donor transplantation and their potential donors occurs within an ever-changing landscape impacted by new evidence and risk assessment techniques. Criteria that were once considered contraindications to living kidney donation are now viewed as standard of care, while new tools identify novel risk markers that were unrecognized in past decades. Recent work suggests that nearly 10% of a cohort of patients with chronic/end-stage kidney disease had an identifiable genetic etiology, many whose original cause of renal disease was either unknown or misdiagnosed. Some also had an incidentally found genetic variant, unrelated to their nephropathy, but medically actionable. These patterns illustrate the substantial potential for genetic testing to better guide the selection of living donors and recipients, but guidance on the proper application and interpretation of novel technologies is in its infancy. In this review, we examine the utility of genetic testing in various kidney conditions, and discuss risks and unresolved challenges. Suggested algorithms in the context of related and unrelated donation are offered.

Summary

Genetic testing is a rapidly evolving strategy for the evaluation of candidates for living donor transplantation and their potential donors that has potential to improve risk assessment and optimize the safety of donation.

Is a Patient with Paget's Disease of Bone Suitable for Living Kidney Donation?-Decision-Making in Lack of Clinical Evidence

Living donor kidney transplantation is a widely performed medical procedure. Living kidney donation requires an in-depth health assessment of candidates. The potential living kidney donor must remain healthy after kidney removal. A consequence of donation can be a decrease in glomerular filtration rate (GFR), and donors can become at risk of developing chronic kidney disease (CKD). We present a rationale for potential living kidney donor withdrawal due to Paget's disease of bone (PDB) based on a literature review. The treatment for PDB includes the use of, for example, non-steroidal anti-inflammatory drugs (NSAIDs), which can lead to acute kidney injury (AKI) as well as CKD, or bisphosphonates, which are not recommended for patients with decreased GFR.

Robotic versus hand-assisted laparoscopic living donor nephrectomy: comparison of two minimally invasive techniques in kidney transplantation

Robot-assisted donor nephrectomy (RDN) is increasingly used due to its advantages such as its precision and reduced learning curve when compared to laparoscopic techniques. Concerns remain among surgeons regarding possible longer warm ischemia time. This study aimed to compare patients undergoing robotic living donor nephrectomy to the more frequently used hand-assisted laparoscopic nephrectomy (HLDN) technique, focusing on warm ischemia time, total operative time, learning curve, hospital length of stay, donor renal function and post-operative complications. Retrospective study comparing RDN to HLDN in a collaborative transplant network. 176 patients were included, 72 in RDN and 104 in HLDN. Left-sided nephrectomy was favored in RDN (82% vs 52%, p < 0.01). Operative time was longer in RDN (287 vs 160 min; p < 0.01), while warm ischemia time was similar (221 vs 213 secs, p = 0.446). The hospital stay was shorter in RDN (3.9 vs 5.7 days, p < 0.01).Concerning renal function, a slightpersistent increase of 7% of the creatinine ratio was observed in the RDN compared to the HLDN group (1.56 vs 1.44 at 1-month checkup, p < 0.01). The results show that RDN appears safe and efficient in comparison to the gold-standard HLDN technique. Warm ischemia time was similar for both techniques, whereas RDN operative time was longer. Patients undergoing RDN had a shorter hospital stay, this being possibly mitigated by differences in center release criteria. Donor renal function needs to be assessed on a longer-term basis for both techniques.

Assessing Renal Function for Kidney Donation. How Low Is Too Low?

Kidney transplantation (KT) is the treatment of choice for patients with end-stage kidney disease (ESKD) with decreased morbi-mortality, improved life quality, and reduced cost. However, the shortage of organs from deceased donors led to an increase in KT from living donors. Some stipulate that living donors have a higher risk of ESKD after donation compared with healthy non-donors. The reason for this is not clear. It is possible that ESKD is due to the nephrectomy-related reduction in glomerular filtration rate (GFR), followed by an age-related decline that may be more rapid in related donors. It is essential to assess donors properly to avoid rejecting suitable ones and not accepting those with a higher risk of ESKD. GFR is a central aspect of the evaluation of potential donors since there is an association between low GFR and ESKD. The methods for assessing GFR are in continuous debate, and the kidney function thresholds for accepting a donor may vary according to the guidelines. While direct measurements of GFR (mGFR) provide the most accurate evaluation of kidney function, guidelines do not systematically use this measurement as a reference. Also, some studies have shown that the GFR decreases with age and may vary with gender and race, therefore, the lower limit of GFR in patients eligible to donate may vary based on these demographic factors. Finally, it is known that CrCl overestimates mGFR while eGFR underestimates it, therefore, another way to have a reliable GFR could be the combination of two measurement methods.

Health inequities and the inappropriate use of race in nephrology

Chronic kidney disease is an important clinical condition beset with racial and ethnic disparities that are associated with social inequities. Many medical schools and health centres across the USA have raised concerns about the use of race - a socio-political construct that mediates the effect of structural racism - as a fixed, measurable biological variable in the assessment of kidney disease. We discuss the role of race and racism in medicine and outline many of the concerns that have been raised by the medical and social justice communities regarding the use of race in estimated glomerular filtration rate equations, including its relationship with structural racism and racial inequities. Although race can be used to identify populations who experience racism and subsequent differential treatment, ignoring the biological and social heterogeneity within any racial group and inferring innate individual-level attributes is methodologically flawed. Therefore, although more accurate measures for estimating kidney function are under investigation, we support the use of biomarkers for determining estimated glomerular filtration rate without adjustments for race. Clinicians have a duty to recognize and elucidate the nuances of racism and its effects on health and disease. Otherwise, we risk perpetuating historical racist concepts in medicine that exacerbate health inequities and impact marginalized patient populations.

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.

Safety and Intraoperative Results in Live Kidney Donors with Vascular Multiplicity After Hand-Assisted Laparoscopy Living Donor Nephrectomy

Background and Purpose

Vascular multiplicity is the most frequent anatomic variation in kidney donors. Despite concerns about risks, these allografts are increasingly used to overcome the shortage of kidney donors. The safety and clinical outcomes in living kidney donors were evaluated with vascular multiplicity after hand-assisted laparoscopic living donor nephrectomy (HALDN).

Patients and Methods

Data from all living kidney donors who underwent HALDN from 2008 to 2021 was retrospectively reviewed. Patients were divided into two groups as single (SRV) and multiple renal vessels (MRV), and a comparative analysis was done. The primary outcomes include operating room time (ORT), days of hospital stay, estimated blood loss, complications, conversion, and re-operations.

Results

MRV were present in 166 out of 612 donors (27.1%). Among those, 10 (1.6%) donors had simultaneous multiple arteries and veins. Additionally, the prevalence of artery and vein multiplicity was 21.8% (n = 134) and 3.5% (n = 22), respectively. Warm ischemia time was significantly different among the two groups but not clinically important. The number of conversions to open technique, the mean ORT, the median blood loss, and days of hospital stay were similar between the SRV and MRV groups, without significant differences. According to the modified Clavien-classification system, no differences were found in the complication rates between the two groups (p = 0.29). Complication rates were 3.3% and 3.6% for the SRV and MRV groups, respectively.

Conclusion

HALDN is a procedure with safe intraoperative results, even with vascular multiplicity. The presence of multiple renal arteries or veins has no negative impact on the outcome of the donor after living donor nephrectomy.

First experiences with dynamic renal [68Ga]Ga-DOTA PET/CT: a comparison to renal scintigraphy and compartmental modelling to non-invasively estimate the glomerular filtration rate

PURPOSE

The determination of the glomerular filtration rate (GFR) is decisive for a variety of clinical issues, for example, to monitor the renal function in radionuclide therapy patients. Renal scintigraphy using glomerularly filtered tracers allows combined acquisition of renograms and GFR estimation but requires repeated blood sampling for several hours. In contrast, dynamic PET imaging using the glomerularly filtered tracer [⁶⁸Ga]Ga-DOTA bears the potential to non-invasively estimate the GFR by compartmental kinetic modelling. Here, we report the, to our knowledge, first comparison of human renal dynamic [⁶⁸Ga]Ga-DOTA PET imaging in comparison to renal scintigraphy and compare PET-derived to serum creatinine-derived GFR measurements.

METHODS

Dynamic [⁶⁸Ga]Ga-DOTA PET data were acquired for 30 min immediately after tracer injection in 12 patients. PET and renal scintigraphy images were visually interpreted in a consensus read by three nuclear medicine physicians. The functional renal cortex was segmented to obtain time-activity curves. The arterial input function was estimated from the PET signal in the abdominal aorta. Single-compartmental tracer kinetic modelling was performed to calculate the GFR using complete 30-min (GFR_PET-30) and reduced 15-min PET data sets (GFR_PET-15) to evaluate whether a shorter acquisition time is sufficient for an accurate GFR estimation. A modified approach excluding minutes 2 to 10 was applied to reduce urinary spill-over effects. Serum creatinine-derived GFR_CKD (CKD-EPI-formula) was used as reference standard.

RESULTS

PET image interpretation revealed the same findings as conventional scintigraphy (2/12 patients with both- and 1/12 patients with right-sided urinary obstruction). Model fit functions were substantially improved for the modified approach to exclude spill-over. Depending on the modelling approach, GFR_CKD and both GFR_PET-30 and GFR_PET-15 were well correlated with interclass correlation coefficients (ICCs) from 0.74 to 0.80 and Pearson's correlation coefficients (PCCs) from 0.74 to 0.81. For a subgroup of patients with undisturbed urinary efflux (n = 9), correlations were good to excellent (ICCs from 0.82 to 0.95 and PCCs from 0.83 to 0.95). Overall, GFR_PET-30 and GFR_PET-15 were excellently correlated (ICCs from 0.96 to 0.99 and PCCs from 0.96 to 0.99).

CONCLUSION

Renal [⁶⁸Ga]Ga-DOTA PET can be a suitable alternative to conventional scintigraphy. Visual assessment of PET images and conventional renograms revealed comparable results. GFR values derived by non-invasive single-compartmental-modelling of PET data show a good correlation to serum creatinine-derived GFR values. In patients with undisturbed urinary efflux, the correlation was excellent. Dynamic PET data acquisition for 15 min is sufficient for visual evaluation and GFR derivation.

Practice Patterns for the Acceptance of Medically Complex Living Kidney Donors with Hematuria, Sickle Cell Trait, Smoking, Illegal Drug Use, or Urological Issues: A Multinational Survey

Background  To review the practice patterns for the acceptance of medically complex living kidney donors (MCLKD) among the transplant providers of the international transplant community. Methods  We distributed a survey globally, through major international transplantation societies, among nephrologists and transplant surgeons (TS). The survey contained questions regarding potential donors with microscopic hematuria, sickle cell trait, renal cysts, kidney stones, smoking, or illegal drug use. Results  There were 239 respondents from 29 countries, including nephrologists (42%) and TS (58%). Although most respondents would investigate microscopic hematuria, one-third of them indicated they would decline these potential donors without investigation. Interestingly, most respondents accepted heavy smokers, intermittent illegal drug users (with advice to quit), and those with incidentally identified kidney stones, remote history of renal colic or simple renal cysts. We found multiple areas of consensus in practice with some interesting differences between nephrologists and TS. Conclusions  This survey highlights the practice patterns of the acceptance of MCLKDs among the international community. In the absence of clear guidelines, this survey provides additional information to counsel kidney donors with microscopic hematuria, sickle cell trait, renal cysts, kidney stones, heavy smoking, or illegal drug use.

Is It Time to Utilize Genetic Testing for Living Kidney Donor Evaluation?

Living donor kidney transplantation is an effective strategy to mitigate the challenges of solid organ shortage. However, being a living kidney donor is not without risk, as donors may encounter short- and long-term complications including the risk of developing chronic kidney disease, end-stage kidney disease, hypertension, and possible pregnancy-related complications. Although the evaluation of potential living donors is a thorough and meticulous process with the intention of decreasing the chance of complications, particularly in donors who have lifetime risk projection, risk factors for kidney disease including genetic predispositions may be missed because they are not routinely investigated. This type of testing may not be offered to patients due to variability and decreased penetrance of symptoms and lack of availability of appropriate genetic testing and genetic specialists. We report a case of a middle-aged woman with a history of gestational diabetes and preeclampsia who underwent an uneventful living kidney donation. She developed postdonation nonnephrotic range proteinuria and microscopic hematuria. Given the risk of biopsy with a solitary kidney, genetic testing was performed and revealed autosomal dominant Alport syndrome. Our case underscores the utility of genetic testing. Hopefully, future research will examine the incorporation of predonation genetic testing into living kidney donor evaluation.