No difference in follow-up estimated glomerular filtration rate between hypertensive and matched nonhypertensive kidney donors

BACKGROUND

According to current guidelines, kidney donor candidates with controlled hypertension using 1 or 2 antihypertensive drugs may be considered as donor. However, this recommendation is based on the study that antihypertensive drug was initiated in mainly "after donor registration" and this may be white-coat hypertension because of donation-related anxiety. We compared the follow-up eGFR between kidney donors with preexisting hypertension and matched nonhypertensive donors.

METHODS

This single-center retrospective study classified 97 living hypertensive donors previously receiving antihypertensive drugs into two groups: 1 drug group (61 donors) and 2 drugs group (36 donors). We compared the follow-up eGFR between each donor previously receiving antihypertensive drugs and three matched nonhypertensive donors in terms of age, sex, and follow-up duration.

RESULTS

At a mean (range) of 51 months (12-214) in the 1 drug group, and 54 months (12-175) in the 2 drugs group after donation, there was no significant difference in follow-up eGFR between hypertensive donors previously receiving antihypertensive drugs and matched controls in each group and in total donors. There was no difference in the incidence of the patients with follow-up eGFR<45mL/min/m2 in each group and their matched controls. Multiple linear regression analysis showed that baseline eGFR was the only independent predictor for the final follow-up eGFR in the total donors.

CONCLUSION

Our results support the current guidelines that donor candidates with controlled hypertension using 1 or 2 antihypertensive drugs may be considered as donors, and may increase the strength of this recommendation.

Seguridad y calidad de vida de los donadores renales. Comparación entre dos técnicas

BACKGROUND

Currently there are no studies that determine the safety and quality of life of kidney donors in Mexico.

OBJECTIVE

To determine the safety of being a kidney donor and the quality of life, comparing the open approach with hand-assisted laparoscopic technique.

METHOD

Observational, cross-sectional, analytical study of the kidney donors in our hospital from January 2015 to December 2018, in two groups: open technique and hand-assisted laparoscopic. To determine safety, the Clavien-Dindo scale and transoperative bleeding were used, and the SF-36 health-related quality of life questionnaire was applied.

RESULTS

There are no reports of peri-operative complications in any type of approach. All the patients obtained a grade I in the Clavien-Dindo scale. When the difference in the score of the SF-36 health-related quality of life questionnaire in kidney donor patients with hand-assisted laparoscopic surgical approach versus open approach was compared, a difference between both means of 14.05 was obtained, with p < 0.0001 in favor of the hand-assisted approach.

CONCLUSIONS

Being a kidney donor is safe and the approach that we recommend is hand-assisted laparoscopic nephrectomy.

Low-level exposure to lead, cadmium and mercury, and histopathological findings in kidney biopsies

BACKGROUND

Lead (Pb), cadmium (Cd) and mercury (Hg) are all nephrotoxic metals, and a large part of the body burden of Cd and Hg is found in the kidneys. There are, however, few studies on associations between exposure to these toxic metals and renal biopsy findings, and none at low-level exposure.

AIM

To examine the hypothesis that low-level concentration of Pb, Cd or Hg in the kidneys is associated with histopathological changes in the kidneys.

METHODS

We determined concentrations of Pb, Cd and Hg in kidney, blood and urine in 109 healthy kidney donors, aged 24-70 years. The renal biopsies were scored according to the Banff classification regarding tubular atrophy, interstitial fibrosis, glomerulosclerosis, arteriosclerosis, and arteriolohyalinosis. Kidney function was assessed based on glomerular filtration rate (GFR) as well as urinary excretion of albumin, low molecular weight proteins, kidney injury molecule 1 and N-acetylglucose aminidase. Associations between metal concentrations and histopathological changes, were assessed in models also including age, sex and smoking.

RESULTS

The median kidney concentrations of Pb, Cd and Hg were 0.08, 13 and 0.21 μg/g, respectively. There were signs of tubular atrophy in 63%, interstitial fibrosis in 21%, glomerulosclerosis in 71%, arteriosclerosis in 47%, and arteriolohyalinosis in 36% of the donors, but, as could be expected, the histopathological findings were limited, mostly Banff grade 1. In models adjusted for age, sex and smoking, kidney Cd was positively associated with tubular atrophy (p = 0.03) and possibly with arteriolohyalinosis (p = 0.06). Kidney Hg was associated with arteriosclerosis (p = 0.004).

DISCUSSION AND CONCLUSIONS

The results suggest that even low levels of Cd in the kidney can induce a mild degree of tubular atrophy. This is in line with previous findings at high-level Cd exposure. The association between kidney Hg and renal arteriosclerosis was unexpected, and may be a chance finding.

[Renal harvest. State of the art.]

Kidney transplantation (KT) is the best treatment for end-stage renal disease. Despite Spain isone of the leading countries in donation, the need for transplantable organs exceeds the available supply. Graft survival depends on the quality of the organ, the damage it suffers during the donation and transplantation process, as well as the risk of rejection. Among the factors that must be controlled and minimized are the ischemia-reperfusion injuries that occurs in the moments surrounding the death of the donor, the procurement and the preservation of the organ until kidney transplantation. Static cold storage is the traditional method of preservation of the organ until the moment of implantation, since it is a technique with wide availability and low cost. The use of perfusion machines in DCD and expanded criteria has shown better short-term results (primary failur delayed on set of function) without affecting recipient orgraft survival. The objective of our article is to review the current situationand the resources available to increase the pool of transplantable organs and their quality. We conducted a systematic review on kidney extraction, donor management, preservation methods and techniques to optimize cadaveric donor kidney donation.

Short- and Mid-Term Impact of Tobacco Smoking on Donor Renal Function Following Living Kidney Donation at a Tertiary Referral Hospital

BACKGROUND

The negative impact of tobacco smoking on renal function has been widely studied. However, there is limited knowledge about the effect of smoking on pre-operative and post-operative renal function in living kidney donors.

OBJECTIVE

The objective of the study was to evaluate the short- and mid-term impact of smoking on donor renal function.

METHODS

This is a retrospective study of 308 patients who underwent living donor nephrectomy (LDN) at a tertiary referral hospital. We compared baseline characteristics as well as functional outcomes following LDN according to history of tobacco smoking. Estimated glomerular filtration rate (eGFR) was calculated with the modification of diet in renal disease equation in 6 time periods: pre-operative, 1 week, 1 month, 6 months, 12 months, and 24 months after surgery. We performed a Kaplan-Meier analysis for chronic kidney disease (CKD) outcome and binary logistic regression analysis to identify risk factors associated with CKD at 24 months of follow-up.

RESULTS

Among donors, 106 (34.4%) reported a smoking history before nephrectomy. Smoking donors had worse pre-operative eGFR than non-smokers (90 ± 26.3 mL/min/1.73m2 vs. 96 ± 27 mL/min/1.73 m2, respectively; p = 0.02) and lower eGFR at 1 week (p = 0.01), 1 month (p ≤ 0.01), 6 months (p = 0.01), and 12 months (p = 0.01) after LDN. Tobacco smoking (OR 3.35, p ≤ 0.01) and age ≥ 40 years at donation (OR 6.59, p ≤ 0.01) were associated with post-operative development of CKD at 24 months after LDN.

CONCLUSIONS

Living kidney donors with a tobacco smoking history had an increased risk of developing chronic kidney disease following nephrectomy. Smoking-cessation strategies should be implemented.

An intersectional gender analysis in kidney transplantation: women who donate a kidney

BACKGROUND

Living-donor transplantation is the best treatment option in patients with chronic kidney failure. Global data show that women are less likely to be kidney recipients than men but are more likely to become living kidney donors. We explored the experience of women who donate a kidney to relatives with biological and socio-cultural ties and to understand the similarities and differences in their experience.

METHODS

A qualitative hermeneutic phenomenological study with an intersectional analysis of gender. Ten women donors accepted in the transplant evaluation period participated, all of whom donated a kidney to a pre-dialysis relative. Two categories were included: women with biological kinship ties (mothers, sisters) and women who have a socio-cultural relationship (wives) with kidney recipient. The data were collected through semi-structured in-depth interviews and analysed using thematic analysis.

RESULTS

Women donate their kidneys in a convinced manner, without worrying about their health, with an optimistic and positive attitude, and without believing that they are acting heroically. Women with biological kinship ties see it as a 'naturalization thing'. In contrast, wives donate conditioned by gender roles, but also as a form of empowerment and as a personal benefit: they donate in order to avoid taking on carer role for their husband and as a way of protecting their children.

CONCLUSION

The study's findings expand the conception of kidney donation as solely altruistic and may help professionals to pay attention to the complexity and intersectionality of features present in women who are living kidney donors.

Donor-related diabetic nephropathy: a comprehensive clinicopathological study

Knowledge on renal involvement in kidney donors with diabetes, that is, diabetic nephropathy (DN), is limited. During the 7 years (2010-2017), 921 postperfusion biopsies were performed for living donors (14%) or deceased donors (86%). The Renal Pathology Society classification schema for DN (class 0-IV) was used. Biopsies with light microscopic changes of DN (at least class IIa) were selected for study. Eleven biopsies (1.2%) showed DN, all from deceased donors (class IIa in 8, class IIb in 2, and class III in 1 biopsy). The glomerular basement membrane thickness ranged from 439 ± 52 to 725 ± 82 nm. These biopsies also displayed arterionephrosclerosis. They were from 9 deceased donors (fulfilling clinical criteria for acceptance in all, diabetes ;[>6 years] in 8, hypertension in 6, and proteinuria [1+] in all). Follow-up biopsies (5-342 weeks after transplant) showed DN of the same class (7 biopsies), probably progression (1), or progression (3). At follow-up (15-416 weeks), all recipients were alive. One graft was lost at 76 weeks because of progressive DN. The other 10 grafts were functioning, but the serum creatinine reached 2.0 to 2.7 mg/dL in 5 of them. Although diabetes is frequent in kidney donors, donor-related DN is unusual. It is observed only in deceased donors, but the risk factors for its development are not known. Donor-related DN may be stable or progress. Whether it resolves, especially for DN in early phase, remains unknown. It may adversely impact the graft outcome with a magnitude proportional to the severity of the tissue injury in the postperfusion biopsies.

Molecular profile of urine extracellular vesicles from normo-functional kidneys reveal minimal differences between living and deceased donors

BACKGROUND

Kidney transplantation (KTx) is the best therapeutic approach for chronic kidney diseases leading to irreversible kidney failure. Considering the origin of the graft, several studies have reported differences between living (LD) and deceased donors (DD) in graft and patient survival. These differences seem to be related to multiple factors including, donor age and time of cold ischemia among others. Many of transplanted organs come from old-aged DDs, in which pre-transplant biopsy is recommended. However, kidney biopsy has several limitations, and there is a need to develop alternatives to assess the status of a kidney before transplantation. As the analysis of urinary extracellular vesicles (uEVs) rendered promising results as non-invasive biomarkers of kidney-related pathologies, this pilot study aimed to investigate whether profiling uEVs of LDs and DDs may be of help to assess the quality of the kidney before nephrectomy.

METHODS

uEVs from 5 living donors and 7 deceased donors were isolated by size-exclusion chromatography, and their protein and miRNA content were analysed by liquid chromatography followed by mass spectrometry and next generation sequencing, respectively. Then, hierarchical clustering and venn diagrams were done with Perseus software and InteractiVenn tool. Specific EVs data bases were also used for Gene Ontology analysis.

RESULTS

Next generation sequencing revealed that uEVs from DDs contained less miRNAs than LDs, but most of the DD-expressed miRNAs were shared with LDs (96%). Only miR-326 (targeting the apoptotic-related Bcl2) was found significantly over-represented in LD. Focusing on the protein content, we detected a low intra-group correlation in both types of donors. Despite these differences, hierarchical clustering of either miRNA or protein data could not identify a differential profile between LDs and DDs. Of note, 90% of transplanted patients had a functional graft after a year from KTx.

CONCLUSIONS

In this pilot study we found that, in normo-functional grafts, minor differences in uEVs profile could not discriminate between LDs and DDs.

Smoking in Renal Transplantation; Facts Beyond Myth

Smoking is one of the preventable leading causes of death worldwide. Most of the studies focused on the association between smoking and cardiovascular disease, pulmonary diseases, malignancy and death. However, the direct effect of smoking on the renal system was undermind. There are emerging evidence correlating tobacco use with pathological changes in the normal kidneys. The effect is more obvious on the renal allograft most probably due to the chronic immune suppression status and the metabolic effect of the drugs. Several studies have documented a deleterious effect of smoking on the renal transplant recipients. Smoking was associated with lowering patient and graft survival. Smoking cessation proved to improve graft survival and to a lesser extent recipient survival. Even receiving a renal transplant from a smoker donor increases the risk of death for the recipient and carries a poorer graft survival compared to non-smoking donors. Most of the studies investigating the effect of smoking were based on self-reporting questioners, which may be misleading due to poor recall or the desire to give socially acceptable answers. This made the need of a reliable biomarker of ultimate importance. Cotinine was proposed as a promising biomarker that may help to provide objective evidence regarding the status of smoking and the dose of nicotine exposure, yet there are still some limitations of its use. The aim of this work is to review the current evidence to improve our understanding of this critical topic. Indeed, this will help to guide better-designed studies in the future.

Glomerular Function and Structure in Living Donors: Lessons from Single Nephron Studies

One third of the kidney transplants performed in the USA come from living kidney donors. The long-term outcome of healthy individuals who donate kidneys is mostly excellent, although recent studies have suggested that living donation is associated with a small absolute increase in the risk of end stage renal failure. Much of our understanding about the progression of kidney disease comes from experimental models of nephron loss. For this reason, living kidney donation has long been of great interest to renal physiologists. This review will summarize the determinants of glomerular filtration and the physiology that underlies post-donation hyperfiltration. We describe the 'remnant kidney' model of kidney disease and the reasons why such progressive kidney disease very rarely ensues in healthy humans following uninephrectomy. We also review some of the methods used to determine glomerular number and size and outline their associations.

Stress predicts the trajectory of wound healing in living kidney donors as measured by high-resolution ultrasound

BACKGROUND

Psychological stress has been shown to be an influential factor on the rate of wound healing; however these findings have been demonstrated predominantly on artificially created wounds. Due to the absence of major co-morbidities, living kidney donors are a unique group in which to study this relationship. This study investigated the effect of preoperative stress and personality on surgical wound healing through the use of high-resolution ultrasound.

METHODS

Living kidney donors due to undergo a hand-assisted laparoscopic donor nephrectomy were asked to complete the Perceived Stress Scale, the Life Orientation Test-Revised and the Ten Item Personality Inventory prior to surgery. High-resolution ultrasound scans of surgical wounds were performed on the first three post-operative days and once following discharge (mean=15.3 days; s.d. 2.8). Two measurements from each image were obtained: wound width (size of wound) and median intensity (a marker of tissue fluid). Latent Growth Curve Models (LGCMs) were used to evaluate wound healing.

RESULTS

52 living kidney donors participated. Higher pre-operative life stress, lower optimism and lower conscientiousness were associated with delayed wound healing in living kidney donors for both outcomes. Increased emotional stability was associated with faster wound healing as demonstrated by a change in median intensity. Possible confounding factors, such as age, BMI, smoking status, local anaesthetic use and wound drain placement were not influential.

CONCLUSIONS

This study, which measured wound healing in a novel patient sample using a novel technique, has demonstrated a negative association between stress and wound healing and the positive influence of optimism, conscientiousness and emotional stability.

Acute Appendicitis following Laparoscopic Live Donor Nephrectomy

Acute abdominal pain following laparoscopic live donor nephrectomy (LLDN) might be a diagnostic dilemma, and prompt diagnosis and management is of paramount importance. Herein, we describe a case of acute appendicitis in a 62-year-old kidney donor who presented with acute abdominal pain 16 days following LLDN with features inconsistent with a diagnosis of acute appendicitis. An ultrasound scan suggested strangulated Spigelian hernia unrelated to the operative wound. Exploration of the wound and mini-laparotomy showed no evidence of wound dehiscence or a hernia, but revealed an inflamed appendix wrapped up with omentum. Appendectomy led to complete recovery of the patient. It is imperative to maintain a high index of suspicion for acute appendicitis in this situation to avoid septic complications that might adversely affect the residual renal function and cause negative impact on kidney donation. To the best of our knowledge, this is the first reported case of acute appendicitis following LLDN.

Living kidney donation: the outcomes for donors

During the past decade, the number of transplantation from living kidney donors has substantially increased worldwide. The rate of increase varies from one country to another. The risk of unilateral nephrectomy to the donor includes perioperative mortality and morbidity plus the long-term risk of living with a single kidney. The rate of perioperative mortality and morbidity is about 0.03% and 10%, respectively. More attention is required to prevent serious complications of laparoscopic donor nephrectomy. A grading system in recording perioperative complications is necessary for making it available to each potential donor. The number of studies on long-term outcome of living donors is very limited. The overall evidence suggests that the risk of end-stage kidney disease is not increased in donors, however, mild renal failure, hypertension and proteinuria are not uncommon in living donors. There is also concern that the incidence of cardiovascular disease may be higher in kidney donors. Establishing living donor registry and follow-up is extremely important. Only through these registries the long-term risk of kidney donation will become more apparent. Because of severe shortage of transplantable kidneys, some transplant centers are now using donors with comorbidities and few centers are involved in transplant tourism with inadequate donor screening and follow-up. Prevention of these unacceptable practices in living kidney donors was emphasized in Amsterdam Forum in 2004 and Istanbul Summit in 2008.