The Evaluation of Kidney Function in Living Kidney Donor Candidates

Comprehensive Surgical Audit of Live-Related Donor Nephrectomy: Procedural Parameters, Demographics, Health Assessments, Complications, and Postoperative Outcomes

BACKGROUND AND OBJECTIVES

End-stage renal disease (ESRD) rates are on the rise globally, including in India. However, the affordability of dialysis treatment remains a significant challenge for many, with costs varying across different regions. Although cost-effective, kidney transplantation faces challenges like a surgeon shortage, lack of infrastructure, and lack of logistic support. The study examines Indian laparoscopic nephrectomy outcomes and their benefits for donor recovery. It covers kidney donor procedural details, demographics, preoperative health evaluations, complications, and one-month follow-up.

METHODS

Ethical approval was obtained, and the study involved 102 cases at the Indira Gandhi Institute of Medical Science, Patna, Bihar, India, from 2019 to 2023. Detailed preoperative assessments, postoperative complications, and one-month follow-up analyses were conducted. Statistical analysis employed SPSS version 17 (IBM Corp., Armonk, NY).

RESULTS

The results revealed an average surgery time of 152.3 min, blood loss of 205 ± 42 ml, and a hospital stay of 4.6 ± 2.2 days. The study found a female predominance (80.39%), with a mean donor age of 35.9 ± 5.2 years. Preoperative assessments showed robust patient health, with glomerular filtration rate (GFR) exceeding the expected threshold and normal urea levels, creatinine, electrolytes, liver enzymes, bilirubin, albumin, and total protein. Post-nephrectomy complications were reported, with females experiencing more difficulties than males.

CONCLUSION

This study underscores the efficiency and safety of laparoscopic nephrectomy in the Indian context, providing valuable insights into donor demographics, preoperative health assessments, complications, and postoperative outcomes. The findings contribute to understanding laparoscopic nephrectomy outcomes and associated risk factors despite certain limitations.

Improving value delivery in living donor kidney transplant through process improvement

INTRODUCTION

Living donor kidney evaluation has substantial time variations with significant intercenter variation. One-day donor evaluation has shown to be clinically efficient and improve transplant rates. However, patients' perception of 1-day evaluation is unknown. We hypothesized that 1 day LKD evaluation will improve patient satisfaction and improve living donation rates.

METHODS

All interested LD candidates from April 2018 to May 2020 were enrolled in the study. Non-directed donors, donors greater than 60 years old, and recipients with more than three donors underwent multi-day evaluation (control group) while the rest underwent 1-day evaluation (intervention group). An anonymous survey was filled by both groups to assess their perceptions on different areas including time, communication, experience, information provided, and their preferences on living donor evaluation.

RESULTS

Donor candidates in the 1-day evaluation group selected that the time from the questionnaire to clinic evaluation took "under 1 month" or "less than 3 months" (62.5% vs. 15.8%, p = .002), with "excellent" for both scheduling process (65% vs. 31.6%, p = .03) and communication (82.5% vs. 57.9%, p = .09) when compared to candidates in the multiple-days evaluation group. One-day candidates felt "very satisfied" with the overall experience (95% vs. 68.4%, p = .02) and felt "extremely well" with the information provided regarding the living donor process (87.5% vs. 47.4%, p = .003) when compared to multiple-day evaluation group. Regardless of the group, 53 (89.8%) patients preferred 1-day evaluation.

CONCLUSION

We demonstrate 1-day living donor evaluation is efficient, patient preferred, and adds value through improved communication, and better overall patient satisfaction.

A Single-Center Study on the Clinical Profiles and Ultrasonographic Assessments of Living Kidney Donors in the Marathwada Region of Maharashtra

Living donor kidney transplantation plays a vital role in renal replacement therapy, particularly in India, where a substantial increase in kidney transplants has been observed. Thorough assessments of living kidney donors are crucial, focusing on parameters such as kidney size and glomerular filtration rate (GFR). Despite the importance of GFR in donor assessments, there is a noticeable lack of data on normal GFR ranges in the Indian population. This study aims to address the gap in knowledge by establishing a reference range for GFR in healthy kidney donors from the Marathwada region of Maharashtra. The research also explores the clinical profiles and ultrasonographic features of living kidney donors. A retrospective analysis was conducted at the Mahatma Gandhi Mission (MGM) Medical College and Hospital in Aurangabad, involving 134 living kidney donors. Inclusion criteria encompassed healthy donors with a BMI of less than 30 kg/m², while donors with uncontrolled hypertension, diabetes, microalbuminuria, or a measured GFR below 70 mL/min/1.73 m² were excluded. Comprehensive medical histories, demographic parameters, and ultrasonographic assessments were conducted, with GFR measured using 99M technetium diethylenetriamine pentaacetate scans. The study reveals that the majority of donors were females (80.6%), and the highest number fell within the 41-50 age group. Parents constituted the primary donor category (68.7%), reflecting a familial inclination toward organ donation. Ultrasonographic assessments indicated larger kidney sizes compared to other studies, suggesting regional or population-specific differences. The mean GFR for the right and left kidneys, as well as the total GFR, was within the expected range. The negative correlation between age and GFR emphasizes the need to consider age in donor assessments. The findings emphasize the unique features of this population, including a higher average age, female preponderance, and larger kidney sizes. The study contributes to the understanding of living kidney donors' profiles in the region and highlights the importance of individualized assessments in the donor selection process.

Performance of estimated glomerular filtration rate equations in Black living kidney donor candidates

INTRODUCTION

New estimated glomerular filtration rate (eGFR) equations using serum creatinine and/or cystatin C have been derived to eliminate adjustment by perceived Black ancestry. We sought to analyze the performance of newer eGFR equations among Black living kidney donor candidates.

METHODS

Black candidates (n = 64) who had measured iothalamate GFR between January 2015 and October 2021 were included, and eGFR was calculated using race adjusted (eGFRcr2009 and eGFRcr-cys2012) and race unadjusted (eGFRcys2012, eGFRcr2021, and eGFRcr-cys2021) CKD-EPI equations. Bias and accuracy were calculated.

RESULTS

The eGFRcr2021 equation had a negative bias of 9 mL/min/1.73 m2 , while other equations showed a modest positive bias. Accuracy within 10% and 30% was greatest using the eGFRcr-cys2021 equation. With the eGFRcr2021 equation, 9.4% of donors with an mGFR > 80 mL/min/1.73 m2 were misclassified as having an eGFR < 80 mL/min/1.73 m2 . eGFR was also compared among 18 kidney donors at 6-24 months post-donation. Post-donation, the percentage of donors with an eGFR < 60 mL/min/1.73 m2 was 44% using the eGFRcr2021 equation compared to 11% using the eGFRcr-cys2021 equation.

CONCLUSION

The CKD-EPICr2021 equation appears to underestimate true GFR in Black living donor candidates. Alternatively, compared to CKD-EPICr2021, the CKD-EPICr-CysC2021 equation appears to perform with less bias and improved accuracy.

Donor Evaluation of Living Kidney Transplantation in the Aging Society

BACKGROUND

Because of the lack of organ donation, living kidney transplantation (LKT) is increasing worldwide. Recently, the number of elderly donors has been increasing, and the patients with end-stage kidney diseases are older than those in the previous decades. Due to the advanced ages, their glomerular filtration rates (GFR) decrease, and the comorbidities such as hypertension, diabetic condition, and obesity are common. The clinicians now have to give their unwilling consent to the LKT from the donors with expanded criteria.

SUMMARY

For the secure selection of donors, proper GFR measuring is essential. Although directly measured GFR (mGFR) was recommended in the guidelines, estimated GFR (eGFR) is used at the initial evaluation of donor renal function clinically. Many equations calculating eGFR have been published so far. In the selection of eGFR equations, the smaller difference between mGFR and eGFR and the closer relationship to the prevalence rates of comorbidities are requisite points. Therefore, we compared the specificity of the various eGFR equations. The eGFR calculated from the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation showed approximate reliability with minimal difference between mGFR and eGFR and the closer relationships to the prevalence rates of comorbidities.

KEY MESSAGE

The CKD-EPI-eGFR presented optimal performance in the donor renal function evaluation. Therefore, eGFR from the CKD-EPI equation is highly recommended in evaluating renal function in LKT donors.

Extracellular Vesicles: The Future of Diagnosis in Solid Organ Transplantation?

Solid organ transplantation (SOT) is a life-saving treatment for end-stage organ failure, but it comes with several challenges, the most important of which is the existing gap between the need for transplants and organ availability. One of the main concerns in this regard is the lack of accurate non-invasive biomarkers to monitor the status of a transplanted organ. Extracellular vesicles (EVs) have recently emerged as a promising source of biomarkers for various diseases. In the context of SOT, EVs have been shown to be involved in the communication between donor and recipient cells and may carry valuable information about the function of an allograft. This has led to an increasing interest in exploring the use of EVs for the preoperative assessment of organs, early postoperative monitoring of graft function, or the diagnosis of rejection, infection, ischemia-reperfusion injury, or drug toxicity. In this review, we summarize recent evidence on the use of EVs as biomarkers for these conditions and discuss their applicability in the clinical setting.

Establishment of a formula for the estimation of kidney depth in adults and its effect on glomerular filtration rate assessment

Background

Gates' analysis method for kidney depth (KD) calculation is the only way to determine the glomerular filtration rate (GFR) of the kidney in clinical practice, which posits that the influence of KD on the GFR is more important than other factors. Computed tomography (CT) measurement of the donor KD can improve the accuracy of GFR measurement by Gates' method but will also increase the radiation exposure of kidney transplantation donors. Thus, it is particularly important to establish an accurate empirical formula for KD measurement that is more consistent with the real KD.

Methods

In total, 326 potential renal transplantation donors were enrolled in this study. Among these, 167 donors were assigned to the training set to estimate the regression formula of KD measured by CT. The remaining 159 donors were included in the validation set to verify the regression formula. The KD measured by CT and its corresponding GFR was taken as the reference standard. The performances of formulas were then compared.

Results

There was no significant statistical difference between the CT-measured KD and the current fitting, Li Q, and Xue JJ formulas (P>0.05). However, significant differences were observed between the KDs calculated using the Taylor, Ma G, and Uchiyama formulas and the CT-measured reference standard KD (P<0.05). Furthermore, there was no notable difference in the GFR_L and GFR_R corresponding to the CT-measured KD with that of the fitting, Ma G, and Xue JJ formulas (P>0.05). There were also marked differences in the GFR_R corresponding to the Li Q's formula (P<0.05), and in the GFR between other estimation methods and the CT measurement (P<0.05).

Conclusions

The fitting formula established in this study can play a more important role if an accurate measurement method of the body thickness at the level of the hilum on the body surface can be found.

Rethinking Chronic Kidney Disease in the Aging Population

The process of aging population will inevitably increase age-related comorbidities including chronic kidney disease (CKD). In light of this demographic transition, the lack of an age-adjusted CKD classification may enormously increase the number of new diagnoses of CKD in old subjects with an indolent decline in kidney function. Overdiagnosis of CKD will inevitably lead to important clinical consequences and pronounced negative effects on the health-related quality of life of these patients. Based on these data, an appropriate workup for the diagnosis of CKD is critical in reducing the burden of CKD worldwide. Optimal management of CKD should be based on prevention and reduction of risk factors associated with kidney injury. Once the diagnosis of CKD has been made, an appropriate staging of kidney disease and timely prescriptions of promising nephroprotective drugs (e.g., RAAS, SGLT-2 inhibitors, finerenone) appear crucial to slow down the progression toward end-stage kidney disease (ESKD). The management of elderly, comorbid and frail patients also opens new questions on the appropriate renal replacement therapy for this subset of the population. The non-dialytic management of CKD in old subjects with short life expectancy features as a valid option in patient-centered care programs. Considering the multiple implications of CKD for global public health, this review examines the prevalence, diagnosis and principles of treatment of kidney disease in the aging population.

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.