Living kidney donor follow-up in a dedicated clinic

Bariatric Surgery in Severely Obese Kidney Donors Before Kidney Transplantation: A Retrospective Study

BACKGROUND

Bariatric surgery (BS) is the optimal approach for sustained weight loss and may alter donation candidacy in potential donors with obesity. We evaluated the long-term effects of nephrectomy after BS on metabolic profile, including body mass index, serum lipids and diabetes, and kidney function of donors.

METHODS

This was a single-center retrospective study. Live kidney donors who underwent BS before nephrectomy were matched for age, gender, and body mass index with patients who underwent BS alone and with donors who underwent nephrectomy alone. Estimated glomerular filtration rate (eGFR) was calculated according to Chronic Kidney Disease Epidemiology Collaboration and adjusted to individual body surface area to create absolute eGFR.

RESULTS

Twenty-three patients who underwent BS before kidney donation were matched to 46 controls who underwent BS alone. At the last follow-up, the study group showed significantly worse lipid profile with low-density lipoprotein of 115 ± 25 mg/dL versus the control group with low-density lipoprotein of 99 ± 29 mg/dL ( P  = 0.036) and mean total cholesterol of 191 ± 32 versus 174 ± 33 mg/dL ( P  = 0.046). The second control group of matched nonobese kidney donors (n = 72) had similar serum creatinine, eGFR, and absolute eGFR as the study group before nephrectomy and 1 y after the procedure. At the end of follow-up, the study group had significantly higher absolute eGFR compared with the control group (86 ± 21 versus 76 ± 18 mL/min; P  = 0.02) and similar serum creatinine and eGFR.

CONCLUSIONS

BS before live kidney donation is a safe procedure that could increase the donor pool and improve their health in the long run. Donors should be encouraged to maintain their weight and avoid adverse lipid profile and hyperfiltration.

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.

Novel insights in classic versus relative glomerular hyperfiltration and implications on pharmacotherapy

PURPOSE OF REVIEW

Glomerular filtration rate (GFR) assessment and its estimation (eGFR) is a long-lasting challenge in medicine and public health. Current eGFR formulae are indexed for standardized body surface area (BSA) of 1.73 m2, ignoring persons and populations wherein the ratio of BSA or metabolic rate to nephron number might be different, due to increased BSA, increased metabolic rate or reduced nephron number. These equations are based on creatinine, cystatin C or a combination of the two, which adds another confounder to eGFR assessment. Unusually high GFR values, also known as renal hyperfiltration, have not been well defined under these equations.

RECENT FINDINGS

Special conditions such as solitary kidney in kidney donors, high dietary protein intake, obesity and diabetes are often associated with renal hyperfiltration and amenable to errors in GFR estimation. In all hyperfiltration types, there is an increased intraglomerular pressure that can be physiologic, but its persistence over time is detrimental to glomerulus leading to progressive glomerular damage and renal fibrosis. Hyperfiltration might be underdiagnosed due to BSA standardization embedded in the formula. Hence, timely intervention is delayed. Reducing intraglomerular pressure in diabetes can be achieved by SGLT2 inhibitors or low protein diet to reverse the glomerulopathy process.

SUMMARY

Accurate identification of glomerular hyperfiltration as a pre-CKD condition needs accurate estimation of GFR in the above normal range should establish a threshold for timely intervention.

Long-term Medical Outcomes of Living Kidney Donors

Historically, to minimize risks, living kidney donors have been highly selected and healthy. Operative risks are well-defined, yet concern remains about long-term risks. In the general population, even a mild reduction in glomerular filtration rate (GFR) is associated with cardiovascular disease, chronic kidney disease, and end-stage kidney disease (ESKD). However, reduction in GFR in the general population is due to kidney or systemic disease. Retrospective studies comparing donors with matched general population controls have found no increased donor risk. Prospective studies comparing donors with controls (maximum follow-up, 9 years) have reported that donor GFR is stable or increases slightly, whereas GFR decreases in controls. However, these same studies identified metabolic and vascular donor abnormalities. There are a few retrospective studies comparing donors with controls. Each has limitations in selection of the control group, statistical analyses, and/or length of follow-up. One such study reported increased donor mortality; 2 reported a small increase in absolute risk of ESKD. Risk factors for donor ESKD are similar to those in the general population. Postdonation pregnancies are also associated with increased risk of hypertension and preeclampsia. There is a critical need for long-term follow-up studies comparing donors with controls from the same era, geographic area, and socioeconomic status who are healthy, with normal renal function on the date matching the date of donation, and are matched on demographic characteristics with the donors. These data are needed to optimize donor candidate counseling and informed consent.

Long-term compensation of renal function after donor nephrectomy

Background

Living donors are the major source of kidneys in countries with a shortage of deceased donors. Kidney donation after careful donor selection is generally accepted as a safe procedure, but the physiologic consequences after donor nephrectomy are not fully verified. In this study we retrospectively reviewed the renal function of the residual kidney in living donors.

Methods

Post-nephrectomy laboratory data of 1,175 living donors (60.7%) from 1,933 living donors who received uninephrectomy from January 1999 to December 2017 at Yonsei University, Severance Hospital, Korea were retrospectively collected. Post-nephrectomy renal function was monitored by the relative ratio of estimated glomerular filtration rate (e-GFR; pre-nephrectomy e-GFR ratio vs. post-nephrectomy e-GFR) that was calculated by the Modification of Diet in Renal Disease formula.

Results

During 36.3±37.6 months of mean follow-up, two cases (0.17%, 2/1,175) of renal failure developed. The mean e-GFR decreased to 64.3±14.2 mL/min/1.73 m² immediately after nephrectomy from 99.2±19.9 mL/min/1.73 m² of the pre-nephrectomy e-GFR. Early decrement of e-GFR was prominent in male and obese donors (body mass index >25 kg/m², P<0.05). The e-GFR ratio increased according to post-nephrectomy duration, and the mean increment degree of e-GFR ratio after nephrectomy calculated by linear regression analysis was 1.94% per year. Unlike the early decrement of e-GFR ratio after nephrectomy, donor factors such as degree of obesity and donor sex did not affect the late increment of e-GFR ratio after nephrectomy (P>0.05).

Conclusions

Our data showed that long-term compensation of the renal function after nephrectomy occurs independently of preoperative donor characteristics.

Short- and Intermediate-Term Outcomes in Living-Related Renal Transplant Donors

OBJECTIVES

The aim of the present study was to evaluate the short- and intermediate-term outcomes of living-related kidney donors in terms of renal function and postnephrectomy complications at a single center in Pakistan.

MATERIALS AND METHODS

Our study included healthy donors who underwent unilateral nephroureterectomy for living-related renal transplant procedures at the Sindh Institute of Urology and Transplantation (Karachi, Pakistan) between January 2005 and January 2006. All patients were evaluated for early postoperative complications and renal functions at last follow-up. The mean follow-up duration was 1.7 ± 1.3 years.

RESULTS

A total of 256 living-related donors underwent nephroureterectomy during the study period, which included 142 men (55.5%) and 114 women (44.5%). The mean age of donors was 33.7 ± 10.0 years. Most donors were between 21 and 40 years old. Of total donors, most were siblings (n = 143, 55.8%), followed by offspring, parents, and spouses. Left nephrectomy was performed in 206 donors (80.4%) and right in 50 donors (19.5%). There were no deaths during transplant. The mean postoperative hospital stay was 6.37 ± 0.95 days. A total of 38 donors (14.8%) had one or more surgical complication. Hypertension developed in 25 (9.7%) and diabetes mellitus in 9 donors (5%). Creatinine clearance was > 90 mL/min in 96 (41%), 60 to 90 mL/min in 120 (51%), and ≤ 60 mL/min in 18 donors (8%).

CONCLUSIONS

Living-related donor nephrectomy remains a valuable source of kidneys for transplant procedures and carries a small risk. With careful donor selection and good surgical management, operative complications can be minimized.

The National Landscape of Living Kidney Donor Follow-Up in the United States

In 2013, the Organ Procurement and Transplantation Network (OPTN)/ United Network for Organ Sharing (UNOS) mandated that transplant centers collect data on living kidney donors (LKDs) at 6 months, 1 year, and 2 years postdonation, with policy-defined thresholds for the proportion of complete living donor follow-up (LDF) data submitted in a timely manner (60 days before or after the expected visit date). While mandated, it was unclear how centers across the country would perform in meeting thresholds, given potential donor and center-level challenges of LDF. To better understand the impact of this policy, we studied Scientific Registry of Transplant Recipients data for 31,615 LKDs between January 2010 and June 2015, comparing proportions of complete and timely LDF form submissions before and after policy implementation. We also used multilevel logistic regression to assess donor- and center-level characteristics associated with complete and timely LDF submissions. Complete and timely 2-year LDF increased from 33% prepolicy (January 2010 through January 2013) to 54% postpolicy (February 2013 through June 2015) (p < 0.001). In an adjusted model, the odds of 2-year LDF increased by 22% per year prepolicy (p < 0.001) and 23% per year postpolicy (p < 0.001). Despite these annual increases in LDF, only 43% (87/202) of centers met the OPTN/UNOS-required 6-month, 1-year, and 2-year LDF thresholds for LKDs who donated in 2013. These findings motivate further evaluation of LDF barriers and the optimal approaches to capturing outcomes after living donation.

Quantifying Postdonation Risk of ESRD in Living Kidney Donors

Studies have estimated the average risk of postdonation ESRD for living kidney donors in the United States, but personalized estimation on the basis of donor characteristics remains unavailable. We studied 133,824 living kidney donors from 1987 to 2015, as reported to the Organ Procurement and Transplantation Network, with ESRD ascertainment via Centers for Medicare and Medicaid Services linkage, using Cox regression with late entries. Black race (hazard ratio [HR], 2.96; 95% confidence interval [95% CI], 2.25 to 3.89; P<0.001) and male sex (HR, 1.88; 95% CI, 1.50 to 2.35; P<0.001) was associated with higher risk of ESRD in donors. Among nonblack donors, older age was associated with greater risk (HR per 10 years, 1.40; 95% CI, 1.23 to 1.59; P<0.001). Among black donors, older age was not significantly associated with risk (HR, 0.88; 95% CI, 0.72 to 1.09; P=0.3). Greater body mass index was associated with higher risk (HR per 5 kg/m2, 1.61; 95% CI, 1.29 to 2.00; P<0.001). Donors who had a first-degree biological relationship to the recipient had increased risk (HR, 1.70; 95% CI, 1.24 to 2.34; P<0.01). C-statistic of the model was 0.71. Predicted 20-year risk of ESRD for the median donor was only 34 cases per 10,000 donors, but 1% of donors had predicted risk exceeding 256 cases per 10,000 donors. Risk estimation is critical for appropriate informed consent and varies substantially across living kidney donors. Greater permissiveness may be warranted in older black candidate donors; young black candidates should be evaluated carefully.

Increasing Use of the Expanded Criteria for Living Kidney Donation and Good Outcomes of Living Kidney Donors in Korea

BACKGROUND

Donor shortage for kidney transplantation may increase the number of expanded-criteria living donors (ECLDs). We investigated recent trends for ECLD use and the long-term outcomes of living kidney donors.

METHODS

We retrospectively analyzed medical records of 1,144 living kidney donors who donated at the Seoul National University Hospital from 1993 to 2015. The expanded criteria for living donation allow the following: age ≥60 years, body mass index >30 kg/m², history of hypertension, estimated glomerular filtration rate <80 mL/min, proteinuria or microscopic hematuria, and fasting glucose >100 mg/dL.

RESULTS

The mean age of donors was 40.7 ± 10.8 years, and there were 600 women (52.4%). A total of 466 donors (40.7%) met the ECLD criteria, and the proportion of ECLDs increased over time. Only 5 donors died after donation over a median follow-up of 7 years. No donor developed end-stage renal disease (ESRD). A urine protein-creatinine ratio ≥0.3 g/gCr was found in 14 patients and was more common in the ECLDs than in the standard-criteria living donors. The follow-up loss rate of donors was 59.3% at 5 years.

CONCLUSIONS

Both mortality and ESRD were very rare in carefully selected living kidney donors. However, living donors should be followed more carefully, because the follow-up loss rate was very high and ECLDs are increasingly used.

Nephron number, hypertension, and CKD: physiological and genetic insight from humans and animal models

The kidneys play a vital role in the excretion of waste products and the regulation of electrolytes, maintenance of acid-base balance, regulation of blood pressure, and production of several hormones. Any alteration in the structure of the nephron (basic functional unit of the kidney) can have a major impact on the kidney's ability to work efficiently. Progressive decline in kidney function can lead to serious illness and ultimately death if not treated by dialysis or transplantation. While there have been numerous studies that implicate lower nephron numbers as being an important factor in influencing susceptibility to developing hypertension and chronic kidney disease, a direct association has been difficult to establish because of three main limitations: 1) the large variation in nephron number observed in the human population; 2) no established reliable noninvasive methods to determine nephron complement; and 3) to date, nephron measurements have been done after death, which doesn't adequately account for potential loss of nephrons with age or disease. In this review, we will provide an overview of kidney structure/function, discuss the current literature for both humans and other species linking nephron deficiency and cardio-renal complications, as well as describe the major molecular signaling factors involved in nephrogenesis that modulate variation in nephron number. As more detailed knowledge about the molecular determinants of nephron development and the role of nephron endowment in the cardio-renal system is obtained, it will hopefully provide clinicians the ability to accurately identify people at risk to develop CKD/hypertension and lead to a shift in patient care from disease treatment to prevention.

Investigating kidney donation as a risk factor for hypertension and microalbuminuria: findings from the Swiss prospective follow-up of living kidney donors

OBJECTIVES

To assess the role of nephrectomy as a risk factor for the development of hypertension and microalbuminuria.

DESIGN

Prospective, long-term follow-up study.

SETTING

Swiss Organ Living-Donor Health Registry.

PARTICIPANTS

All living kidney donors in Switzerland between 1993 and 2009.

INTERVENTIONS

Data on health status and renal function before 1 year and biennially after donation were collected.

PRIMARY AND SECONDARY OUTCOME MEASURES

Comparison of 1-year and 5-year occurrences of hypertension among normotensive donors with 1-year and 5-year estimates from the Framingham hypertension risk score. Multivariate random intercept models were used to investigate changes of albumin excretion after donation, correcting for repeated measurements and cofactors such as age, male gender and body mass index.

RESULTS

A total of 1214 donors contributed 3918 data entries with a completed biennial follow-up rate of 74% during a 10-year period. Mean (SD) follow-up of donors was 31.6 months (34.4). Median age at donation was 50.5 years (IQR 42.2-58.8); 806 donors (66.4%) were women. Donation increased the risk of hypertension after 1 year by 3.64 (95% CI 3.52 to 3.76; p<0.001). Those participants remaining normotensive 1 year after donation return to a risk similar to that of the healthy Framingham population. Microalbuminuria before donation was dependent on donor age but not on the presence of hypertension. After nephrectomy, hypertension became the main driver for changes in albumin excretion (OR 1.19; 95% CI 0.13 to 2.25; p=0.03) and donor age had no effect.

CONCLUSIONS

Nephrectomy propagates hypertension and increases susceptibility for the development of hypertension-induced microalbuminuria.

Obesity and metabolic syndrome in kidney transplantation

The epidemic of obesity and metabolic syndrome (MS) contributes to the rapid growth of chronic kidney disease (CKD) and end-stage renal disease (ESRD). There is a reverse epidemiology, known as the "obesity paradox," in ESRD patients receiving maintenance dialysis. Obese patients are routinely referred for kidney transplant, and they have more surgical and medical complications than non-obese patients. However, compared to dialysis, kidney transplant provides a survival benefit for obese patients. After kidney transplant, obese patients tend to gain more body weight, and non-obese patients can develop new-onset obesity/MS. Obesity/MS is not only associated with serious morbidities, but also compromises the long-term graft and patient survival. The immunosuppressive drugs commonly used as maintenance therapy, including corticosteroids, calcineurin inhibitors and mammalian target-of-rapamycin inhibitors, contribute to obesity/MS. Development of novel immunosuppressive drugs free of metabolic adverse effects is needed, so that the full potential and benefits of kidney transplantation can be realized.

A kidney transplantation model in a low-resource country: an experience from Pakistan

Pakistan is a low-resource country with a population of 185 million where expenditure on health is 1.3% of the gross national product. The estimated incidence of end-stage renal disease (ESRD) is 100 per million of the population. The paucity and high costs of renal replacement therapy render more than 90% of the ESRD population disenfranchised from replacement therapy. Our center, which is a government sector organization, established as an integrated dialysis and living related renal transplant program in the 1980s, where all services were provided free of cost to all patients with life-long follow-up care including medications. The model was based on a concept of community/government partnership where the contributions to funds vary between 40% and 60% for each partner. The model has been self sustaining for 25 years, with an annual budget of $28 million in 2010. Presently, over 600 patients are dialyzed each day and each week, 7–10 patients have received live related transplants. The overall 1- and 5-year graft survival rate of 3150 transplants is 92% and 85%, respectively. Free dialysis and transplantation established our institute as a focus of transplantation in the country. This model therefore allowed the institute to have a vital role in the campaign against transplant tourism and in the promulgation of the transplant law. It shows that in low-resource countries, specialized centers in the government sector can, with community support, provide high-quality ESRD care to the disenfranchised population.

Systematic review and meta-analysis of the relation between body mass index and short-term donor outcome of laparoscopic donor nephrectomy

In this era of organ donor shortage, live kidney donation has been proven to increase the donor pool; however, it is extremely important to make careful decisions in the selection of possible live donors. A body mass index (BMI) above 35 is generally considered as a relative contraindication for donation. To determine whether this is justified, a systematic review and meta-analysis were carried out to compare perioperative outcome of live donor nephrectomy between donors with high and low BMI. A comprehensive literature search was performed in MEDLINE, Embase, and CENTRAL (the Cochrane Library). All aspects of the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement were followed. Of 14 studies reviewed, eight perioperative donor outcome measures were meta-analyzed, and, of these, five were not different between BMI categories. Three found significant differences in favor of low BMI (29.9 and less) donors with significant mean differences in operation duration (16.9 min (confidence interval (CI) 9.1-24.8)), mean difference in rise in serum creatinine (0.05 mg/dl (CI 0.01-0.09)), and risk ratio for conversion (1.69 (CI 1.12-2.56)). Thus, a high body mass index (BMI) alone is no contraindication for live kidney donation regarding short-term outcome.

Long-term risk of hypertension and chronic kidney disease in living kidney donors

OBJECTIVE

The aim of this study was to assess the long-term risks of chronic kidney disease and arterial hypertension in living kidney donors.

METHODS

Donors who were followed for more than 1 year after nephrectomy were included. We assessed each donor's blood pressure, urine protein, and estimated glomerular filtration rate (eGFR).

RESULTS

The follow-up rate was 11% (154 out of 1,356 donors), only 19% of whom were followed by nephrologists. Blood pressure had increased from 113/75 to 116/77 mm Hg (P < .01), urinary protein excretion after donation did not increase, and renal function was well preserved after donor nephrectomy. However, 33 patients (21.4%) showed a decreased eGFR of <60 mL/min/1.73 m(2), and 3 donors developed end-stage renal disease that required renal replacement therapy.

CONCLUSIONS

The follow-up rate of living donors after donation was low, and we observed an increased risk of developing chronic kidney disease after donation.

Paid donation: a global view

Paying for kidney or other organ donation has lead to heated debates about donor and recipient welfare. Many have argued that paying for donation leads to coercion and exploitation of the poor, and, in the end, produces more harm than good. Others have said that payment helps the poor, and we should all have sovereignty over our bodies and, thus, should be allowed to donate for remuneration. Although World Health Organizations and governments in many countries have now banned the process of paying for donation, there is still ongoing payment legally and illegally. Thus, this timely set of three articles from Iran, Pakistan, and the Philippines, where paid donation has been extensively performed, will allow the reader to decide for themselves whether the benefits and/or harms of this practice are now clear.

A renal transplantation model for developing countries

The estimated incidence of end-stage renal disease (ESRD) in Pakistan is 100 per million population. Paucity and high costs of renal replacement therapy allows only 10% to get dialysis and 4-5% transplants. Our center, a government organization, started a dialysis and transplant program in 1980s where all services were provided free of charge to all patients. It was based on the concept of community government partnership funded by both partners. The guiding principles were equity, transparency, accountability and development of all facilities under one roof. This partnership has sustained itself for 30 years with an annual budget of $25 million in 2009. Daily 600 patients are dialyzed and weekly 10-12 receive transplants. One- and 5-year graft survival of 3000 transplants is 92% and 85%, respectively. The institute became a focus of transplantation in Pakistan and played a vital role in the campaign against transplant tourism and in promulgation of transplant law of 2007, and also helped to increase altruistic transplants in the country. This model emphasizes that in developing countries specialized centers in government sector are necessary for transplantation to progress and community support can make it available to the common man.

Understanding the effects of chronic kidney disease on cardiovascular risk: are there lessons to be learnt from healthy kidney donors?

Chronic kidney disease (CKD) is now a recognized global public health problem. It is highly prevalent and strongly associated with hypertension and cardiovascular disease (CVD); far more patients with a glomerular filtration rate below 60 ml min(-1) per 1.73 m(2) will die from cardiovascular causes than progress to end-stage renal disease. A better understanding of the complex mechanisms underlying the development of CVD among CKD patients is required if we are to begin devising therapy to prevent or reverse this process. Observational studies of CVD in CKD are difficult to interpret because renal impairment is almost always accompanied by confounding factors. These include the underlying disease process itself (for example, diabetes mellitus and systemic vasculitis) and the complications of CKD, such as hypertension, anaemia and inflammation. Kidney donors provide an ideal opportunity to study healthy subjects without manifest vascular disease who experience an acute change from having normal to modestly impaired renal function at the time of uninephrectomy. Prospectively examining the cardiovascular consequences of uninephrectomy using donors as a model of CKD may provide useful insight into the pathophysiology of CVD in CKD and, therefore, into how the CVD risk associated with renal impairment might eventually be reduced.

Clinical analysis of living related renal transplantation with donors older than 50 years in China

OBJECTIVE

The objective of this study was to investigate whether kidney grafts from living related donors older than 50 years were safe for the donors and recipients in the long term.

METHODS

One hundred seven living related donor kidney transplantations were performed in our center from April 1994 to December 2007. No prisoners or organs from prisoners were used in the collection of these data. Donors were divided into 2 groups: >50 years of age (range, 51-78 years), designated as the study group, and ≤50 years of age (range, 21-50 years), designated as the control groups. The mean time of follow-up was 49 months (range, 12-180 months). Clinical data were compared, including donor serum creatinine (Scr) levels, glomerular filtration rates (GFR) before and after the procedures operative complications, and postoperative short-term and long-term recovery of renal function in recipients as well as their complications and recipient and kidney survivals.

RESULTS

All operations were successfully performed. Before the operation, the mean Scr and GFR were 82.16 ± 10.86 umol/L and 85.82 ± 6.26 mL/min, respectively, in the study group versus 78.66 ± 10.41 umol/L and 88.74 ± 9.44 mL/min, respectively, in the control group. There were no significant differences in mean Scr or GFR values between the groups at various preoperative or postoperative times (P > .05). No severe perioperative complications occurred, and no subsequent renal function failure was observed upon long-term follow-up of donors in the 2 groups. Comparisons of recipient age, gender ratio, duration on dialysis, HLA matches, cold/warm ischemia times, and immunosuppression therapy showed a correlations between the 2 groups. Mean Scr levels of recipients, which were compared from 1 week to 3 years following surgery, were slightly higher among the control than the study group, but the difference was not significant (P > .05). There were no significant differences between the study and control groups in 1-,3-,5-, and 8-year recipient/graft survival rates (P > .05).

CONCLUSIONS

Long-term follow-up showed that transplantations using grafts from donors older than 50 years of age yielded similar results to those with younger donors.

Short- and long-term outcomes of living donors in Tunisia: a retrospective study

Despite initiatives to increase cadaveric donation, there is still a shortfall in donor organs. Kidneys from living donors now makes a significant contribution to increasing the number of organs available for transplantation in Tunisia. We performed a retrospective study of 405 kidney transplantations, including 321 (79.3%) from living donors performed from June 1986 to December 2007. We obtained information on only 162 (50.4%), namely, 64 men (39.5%) and 98 women (60.5%), whose mean age at the time of donation was 42.3 ± 12.2 years. Twelve (8.22%) perioperative complications occurred: wound infections (n = 4), pneumothorax (n = 4), phlebitis (n = 1), hematomas (n = 2), and urinary infection (n = 1). The mean follow-up period was 117.4 ± 74.4 months. Hypertension occurred in 42 donors (25.9%) with mean values of 134 ± 20 for systolic and 79 ± 10 for diastolic blood pressure. Twelve donors (7.4%) developed proteinuria (mean proteinuria, 0.08 ± 1.25 g/d). Renal insufficiency was found in 28 donors (19.44%), 2 of whom developed chronic renal failure requiring dialysis at intervals of 36 and 84 months. In both cases, we diagnosed a familial form of focal segmental glomerulosclerosis. Two donors (1.2%) died within 10 years after kidney donation due to senility. The relatively favorable outcomes suggest that living-donor kidney transplantation is an acceptable approach, in view of the superior results it yields in recipients. However, efforts to increase the number of cadaveric donors in Tunisia should be made. It is also important to develop a registry of long-term kidney function after kidney donation.

Change in renal function after laparoscopic donor nephrectomy for kidney transplantation

BACKGROUND

Laparoscopic donor nephrectomy (LDN) has become the method of choice for living-donor kidney transplantation. However, LDN may result in decreased renal function in the donor, and risk of end-stage renal failure has been reported.

OBJECTIVE

To evaluate changes in renal function after LDN.

PATIENTS AND METHODS

The study included 51 living donors of renal transplants between March 2002 and December 2008. Before kidney donation, we computed the initial function of the kidney preserved in the donor using 24-hour creatinine clearance (Ccr) and functional ratio as revealed at technetium 99m dimercaptosuccinic acid renal scanning. After kidney donation, serum creatinine concentration (sCr) and Ccr were calculated on postoperative day 2 and every 3 months thereafter.

RESULTS

After LDN, mean sCr increased immediately, from 0.90 to 1.31, as did Ccr of the kidney preserved in the donor, from 58.2 to 79.6, a 36.9% increase. A greater percent increase in function was observed in younger donors and those with lower initial Ccr of the preserved kidney. Although 9.8% of donors demonstrated slightly decreased renal function of the preserved kidney at last follow-up, renal function was adequately preserved in most donors.

CONCLUSION

Younger donors and those with lower initial function of the preserved kidney before nephrectomy demonstrate a greater increase in function after nephrectomy. Age might be a risk factor for decreased renal function after LDN. Older potential living donors may need more careful evaluation before kidney donation.

Long-term outcomes of kidney donors

PURPOSE OF REVIEW

Partial renal ablation in laboratory animals leads initially to compensatory glomerular hyperfiltration and progressive, sclerotic kidney disease. In addition, modest declines in kidney function are associated with premature mortality in epidemiological studies. Hence, the long-term safety of living-kidney donation is an important issue. The purpose of this review was to examine existing research on outcomes among living-kidney transplant donors, with a focus on longer term outcomes.

RECENT FINDINGS

Although studies with sibling controls are unavailable, the current evidence base suggests that kidney donors have mortality and end-stage renal disease risks that are equivalent to similar individuals in the general population. Although findings for albuminuria and hypertension vary between studies, risks may be acceptable if donors receive optimal follow-up and care. Parenthetically, viewed as an experimental model of kidney-function loss, the neutrality of outcomes among donors may have major implications for the population at large: the robust associations between modest declines in kidney function and mortality seen in the general population suggest a confounded relationship and finding these confounders could have major implications for future research directions and for public health.

SUMMARY

Long-term outcomes suggest that kidney donation is not a major threat to longevity.

Medical follow-up of living kidney donors by 1 year after nephrectomy

BACKGROUND

Concerns have been raised that many kidney donors do not receive adequate medical care after nephrectomy. In 2003, our program developed a policy recommending that donors receive medical follow-up by 12 months postnephrectomy. We hypothesized that medically complex donors would have a higher rate of follow-up than other donors.

METHODS

A retrospective cohort study of 137 live kidney donors from a single center was performed. Donors were considered medically complex if they had hypertension, body mass index of 30 or greater, nephrolithiasis, age 65 years or older, creatinine clearance less than 80 mL/min/1.73 m(2), or had a first-degree relative with diabetes mellitus. Adequate follow-up was defined as one visit with a nephrologist at our center, or blood pressure, serum creatinine, and urinalysis checked elsewhere.

RESULTS

Eighty-three donors (61%) had adequate follow-up, 42 did not, and 12 could not be contacted. At multivariate logistic regression, donors with adequate follow-up were more likely to be medically complex (odds ratio, 2.48; 95% confidence interval 1.18-5.23; P = .02) and older than donors with inadequate follow-up (odds ratio, 1.46 per 10 years of age; 95% confidence interval, 1.01-2.10; P = .04).

CONCLUSION

A substantial minority of donors do not receive recommended care by 1 year after nephrectomy.

Long-term renal function and cardiovascular disease risk in obese kidney donors

BACKGROUND AND OBJECTIVES

Increasing demand for live-donor kidneys has encouraged the use of obese donors despite the absence of long-term outcome data and evidence that obesity can adversely affect renal function. We wished to determine whether obesity increased the risk for renal dysfunction and other medical comorbidities in donors several years after donation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Ninety-eight patients who donated a kidney 5 to 40 years previously were stratified according to body mass index (BMI) at donation and evaluated for renal dysfunction and risk factors for cardiovascular disease. Patients who were from the 2005 through 2006 National Health and Nutrition Examination Survey database; did not have renal disease; and were matched for age, gender, race, and BMI served as two-kidney control subjects.

RESULTS

Renal function in obese (BMI > or =30) and nonobese (BMI <30) donors was similar, and both donor groups had reduced renal function compared with BMI-matched two-kidney control subjects. Obesity was associated with more hypertension and dyslipidemias in both donors and two-kidney control subjects; however, there were no significant differences between the two groups within each BMI category.

CONCLUSIONS

These results indicate that obese donors are not at higher risk for long-term reduced renal function compared with nonobese donors and that the increased incidence of hypertension and other cardiovascular disease risk factors in obese donors is due to their obesity and is not further exacerbated by nephrectomy. These findings support the current practice of using otherwise healthy overweight and obese donors but emphasize the need for more intensive preoperative education and postoperative health care maintenance in this donor group.

Commercial transplants in local Pakistanis from vended kidneys: a socio-economic and outcome study

Donor shortage and absence of transplant law lead to unrelated commercial transplants in Pakistan. We report the socio-economic and outcome parameters of 126 local recipients of unrelated kidney vendor transplants presenting to our institute between 1997 and 2007. Their outcome was compared with 180 recipients of living-related donor transplants matched for age, gender and transplant duration as controls. Age of commercial recipients was 35.63 +/- 11.57 years with an M:F ratio of 2.4:1. Majority (92%) were transplanted in northern Pakistan paying US$7271 +/- 2198. All were educated with 50% being graduates or above and rich earning a monthly salary of US$517 +/- 518 with 44% earning >US$500. Comparison of commercial recipients with controls showed high comorbidities 35 (28%) vs. 14 (8%) (P = 0.0001) with diabetes, hepatitis-C and cardiovascular diseases. Donor age was 29.97 +/- 6.16 vs. 32.63 +/- 9.3 years (P = 0.035). Biologic agents induction in 101 (80%) vs. 14 (8%) (P = 0.0001), acute rejections in 42 (33%) vs. 31 (17%) (P = 0.005), 1-year creatinine 1.84 +/- 1.28 vs. 1.27 +/- 0.4 mg/dl (P = 0.0001), surgical complications 28 (22%) vs. 14 (8%) (P = 0.001), tuberculosis 14 (11%) vs. 6 (6%) (P = 0.007), acute hepatitis 20 (16%) vs. 3 (2%) (P = 0.0001), cytomegalovirus 33 (26%) vs. 21 (11%) (P = 0.001) and recurrent urinary tract infection 35 (28%) vs. 30 (16%) (P = 0.034). Overall 1- and 5-year graft survival was 86% and 45% vs. 94% and 80%, respectively (P = 0.00001). Total deaths were 34 (27%) vs. 12 (6.0%) (P = 0.001). In conclusion, recipients of the vended kidneys are poor candidates, educated, rich and often self-selecting. Their outcome is poor, which will leave them poorer still and back to dialysis if not death.

Laparoscopic donor nephrectomy

Since it first was performed in 1995, laparoscopic donor nephrectomy (LDN) has grown to be the standard of care in most transplant centers in the United States. This article reviews the current indications, selection criteria, surgical approaches, outcomes, and complications of LDN.

Substantial variation in the acceptance of medically complex live kidney donors across US renal transplant centers

Concern exists about accepting live kidney donation from 'medically complex donors'--those with risk factors for future kidney disease. This study's aim was to examine variation in complex kidney donor use across US transplant centers. We conducted a retrospective cohort study of live kidney donors using organ procurement and transplantation network data. Donors with hypertension, obesity or estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m(2) were considered medically complex. Among 9319 donors, 2254 (24.2%) were complex: 1194 (12.8%) were obese, 956 (10.3%) hypertensive and 392 (4.2%) had low eGFR. The mean proportion of medically complex donors at a center was 24% (range 0-65%). In multivariate analysis, donor characteristics associated with medical complexity included spousal relationship to the recipient (OR 1.29, CI 1.06-1.56, p < 0.01), low education (OR 1.19, CI 1.04-1.37, p = 0.01), older age (OR 1.01 per year, CI 1.01-1.02, p < 0.01) and non-US citizenship (OR 0.70, CI 0.51-0.97, p = 0.03). Renal transplant centers with the highest transplant volume (OR 1.26, CI 1.02-1.57, p = 0.03), and with a higher proportion of (living donation)/(all kidney transplants) (OR 1.97, CI 1.23-3.16, p < 0.01) were more likely to use medically complex donors. Though controversial, the use of medically complex donors is widespread and varies widely across centers.

Substantial variation in the acceptance of medically complex live kidney donors across US renal transplant centers

Concern exists about accepting live kidney donation from 'medically complex donors'--those with risk factors for future kidney disease. This study's aim was to examine variation in complex kidney donor use across US transplant centers. We conducted a retrospective cohort study of live kidney donors using organ procurement and transplantation network data. Donors with hypertension, obesity or estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m(2) were considered medically complex. Among 9319 donors, 2254 (24.2%) were complex: 1194 (12.8%) were obese, 956 (10.3%) hypertensive and 392 (4.2%) had low eGFR. The mean proportion of medically complex donors at a center was 24% (range 0-65%). In multivariate analysis, donor characteristics associated with medical complexity included spousal relationship to the recipient (OR 1.29, CI 1.06-1.56, p < 0.01), low education (OR 1.19, CI 1.04-1.37, p = 0.01), older age (OR 1.01 per year, CI 1.01-1.02, p < 0.01) and non-US citizenship (OR 0.70, CI 0.51-0.97, p = 0.03). Renal transplant centers with the highest transplant volume (OR 1.26, CI 1.02-1.57, p = 0.03), and with a higher proportion of (living donation)/(all kidney transplants) (OR 1.97, CI 1.23-3.16, p < 0.01) were more likely to use medically complex donors. Though controversial, the use of medically complex donors is widespread and varies widely across centers.

Health status and renal function evaluation of kidney vendors: a report from Pakistan

Unrelated kidney transplants have lead to commerce and kidney vending in Pakistan. This study on 104 vendors reports demographics, history, physical and systemic examination, ultrasound findings, renal and liver function and GFR by Cockcroft-Gault. Results were compared with 184 age, sex and nephrectomy duration matched living-related donors controls. Comparison of vendors versus controls showed mean age of 30.55 +/- 8.1 versus 30.65 +/- 7.85 (p = 0.91) years, M:F of 4.5:1 versus 4.2:1 and nephrectomy period of 33.89 +/- 30 versus 32.01 +/- 29.71 (p = 0.60) months respectively. Of the vendors 67% were bonded laborers earning <50 $/month as compared to controls where 68% were skilled laborers and self-employed earning >100 $/month. History of vendors revealed jaundice in 8%, stone disease in 2% and urinary tract symptoms in 4.8%. Postnephrectomy findings between vendors versus donors showed BMI of 21.02 +/- 2.8 versus 23.02 +/- 4.2 (p = 0.0001), hypertension in 17% versus 9.2% (p = 0.04), serum creatinine (mg/dL) of 1.17+/-0.21 versus 1.02 +/- 0.27 (p = 0.0001), GFR (mL/min) of 70.94 +/- 14.2 versus 95.4 +/- 20.44 (p = 0.0001), urine protein/creatinine of 0.150 +/- 0.109 versus 0.10 +/- 0.10 (p = 0.0001), hepatitis C positivity in 27% versus 1.0% (p = 0.0001) and hepatitis B positive 5.7% versus 0.5% (p = 0.04), respectively. In conclusion, vendors had compromised renal function suggesting inferior selection and high risk for developing chronic kidney disease in long term.

A socioeconomic survey of kidney vendors in Pakistan

In recent years, Pakistan has emerged as one of the largest centres for commerce and tourism in renal transplantation. Kidney vendors belong to Punjab in eastern Pakistan, the agricultural heartland, where 34% people live below poverty line. We report results of a socioeconomic and health survey of 239 kidney vendors. The mean age was 33.6 +/- 7.2 years (M:F 3.5:1). Mean nephrectomy period was 4.8 +/- 2.3 years. Ninety per cent of the vendors were illiterate. Sixty-nine per cent were bonded labourers who were virtual slaves to landlords, labourers 12%, housewives 8.5% and unemployed 11%. Monthly income was $US15.4 +/- 8.9 with 2-11 dependents per family. Majority (93%), vended for debt repayment with mean debt of $1311.4 +/- 819. The mean agreed sale price was $1737 +/- 262. However, they received $1377 +/- 196 after deduction for hospital and travel expenses. Postvending 88% had no economic improvement in their lives and 98% reported deterioration in general health status. Future vending was encouraged by 35% to pay off debts and freedom from bondage. This study gives a snapshot of kidney vendors from Pakistan. These impoverished people, many in bondage, are examples of modern day slavery. They will remain exploited until law against bondage is implemented and new laws are introduced to ban commerce and transplant tourism in Pakistan.

Routine Use of Ambulatory Blood Pressure Monitoring in Potential Living Kidney Donors

BACKGROUND AND OBJECTIVES

Most transplant centers exclude prospective living kidney donors with hypertension from donation. Centers routinely identify hypertension using BP measured in the clinic, but it is not clear that clinic BP accurately detects the presence or absence of hypertension in potential donors. We therefore conducted a prospective study to determine the impact of routine ambulatory BP monitoring on diagnosis of hypertension in potential donors and the value of other baseline characteristics in predicting ambulatory BP results.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We compared classification of hypertension status by clinic BP and by ambulatory BP monitoring in 178 potential living kidney donors.

RESULTS

Of 63 individuals with hypertension by clinic BP, 62% had white-coat hypertension by ambulatory BP and were therefore eligible to donate. Of 115 individuals who were normotensive by clinic BP, 17% had masked hypertension by ambulatory BP and were excluded from donation. Individuals with masked hypertension were older, were more likely to be male, and had a somewhat higher clinic BP than individuals with sustained normotension. Individuals with white-coat hypertension had a somewhat lower clinic diastolic BP than individuals with sustained hypertension.

CONCLUSIONS

Routine ambulatory BP monitoring may identify a large number of individuals with white-coat hypertension and a smaller but significant number of individuals with masked hypertension, ensuring adequate protection of potential donors and accurate assessment of donor risk. Differences in baseline characteristics are small and are not clinically useful in distinguishing individuals with masked hypertension from individuals with sustained normotension or individuals with white-coat hypertension from individuals with sustained hypertension, demonstrating the importance of ambulatory BP monitoring in this population.

Corporeal Weight Gain and Metabolic Syndrome in Living Kidney Donors After Nephrectomy

The number of healthy individuals undergoing unilateral nephrectomy for kidney donation is increasing world-wide. Obesity and nephron reduction could promote a decline in the glomerular filtration rate (GFR) and an increase in urinary protein excretion in these individuals. Metabolic Syndrome (MS) is also a risk factor for these patients. This study evaluated GFR, urinary protein excretion, and the possibility of one or more components of MS in this group.

METHODS

Twenty live kidney donors were evaluated at an average of 10 years after nephrectomy. We obtained measurements of systolic blood pressure, diastolic blood pressure, and waist circumference. We estimated renal function, urinary protein excretion, triglycerides, high-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and fasting plasma glucose levels. The GFR was calculated through the estimated creatinine clearance using the Cokcroft-Gault equation (eGFR).

RESULTS

Of the 20 participants, four developed MS. The patients with a greater number of MS components showed a greater eGFR. Only seven donors (35%) showed a normal blood pressure. Serum creatinine level changes were observed in three patients, and in five there was increased urinary protein excretion.

CONCLUSION

This study showed the possibility that corporeal weight gain and MS may be additional overburdens on the GFR of the remaining kidney.