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Proteinuria predicts accelerated decline in kidney function in kidney transplant recipients (KTRs). We hypothesized that aberrant filtration of complement factors causes intraluminal activation, apical membrane attack on tubular cells, and progressive injury. Biobanked samples from two previous studies in albuminuric KTRs were used. The complement-activation split products C3c, C3dg, and soluble C5b-9-associated C9 neoantigen were analyzed by ELISA in urine and plasma using neoepitope-specific antibodies. Urinary extracellular vesicles (uEVs) were enriched by lectin and immunoaffinity isolation and analyzed by immunoblot analysis. Urine complement excretion increased significantly in KTRs with an albumin-to-creatinine ratio of ≥300 mg/g compared with <30 mg/g. Urine C3dg and C9 neoantigen excretion correlated significantly to changes in albumin excretion from 3 to 12 mo after transplantation. Fractional excretion of C9 neoantigen was significantly higher than for albumin, indicating postfiltration generation. C9 neoantigen was detected in uEVs in six of the nine albuminuric KTRs but was absent in non-albuminuric controls ( n = 8). In C9 neoantigen-positive KTRs, lectin affinity enrichment of uEVs from the proximal tubules yielded signal for iC3b, C3dg, C9 neoantigen, and Na + -glucose transporter 2 but only weakly for aquaporin 2. Coisolation of podocyte markers and Tamm-Horsfall protein was minimal. Our findings show that albuminuria is associated with aberrant filtration and intratubular activation of complement with deposition of C3 activation split products and C5b-9-associated C9 neoantigen on uEVs from the proximal tubular apical membrane. Intratubular complement activation may contribute to progressive kidney injury in proteinuric kidney grafts. NEW & NOTEWORTHY The present study proposes a mechanistic coupling between proteinuria and aberrant filtration of complement precursors, intratubular complement activation, and apical membrane attack in kidney transplant recipients. C3dg and C5b-9-associated C9 neoantigen associate with proximal tubular apical membranes as demonstrated in urine extracellular vesicles. The discovery suggests intratubular complement as a mediator between proteinuria and progressive kidney damage. Inhibitors of soluble and/or luminal complement activation with access to the tubular lumen may be beneficial.

Background: To characterize level and predictors of influenza and pneumococcal vaccine uptake among Danish kidney transplant recipients (KTR) and kidney transplant waiting list patients (WLP)., Methods: A cross-sectional survey based on self-reported vaccine uptake including WLP and KTR ≤ 1½ years post transplantation. Descriptive statistics and logistic regression analyses identifying factors associated with influenza vaccine uptake in the latest season were performed., Results: A total of 220 participants were included in the study, 54% KTR and 46% WLP. Self-reported influenza vaccine uptake in the latest season was overall 41.8%. Uptake of influenza vaccine on any prior season apart from the latest season was 53.2% and significantly higher among WLP than KTR (P = .007). Pneumococcal vaccine uptake was only 4% overall. The only factor positively associated with influenza vaccine uptake in the latest season was any prior influenza vaccine uptake (OR 5.79, CI95 2.44-13.76) (P < .001). Recommendations given by other persons (non-physician) were negatively associated with receiving the influenza vaccination in the latest season (OR 0.34, CI95 0.13-0.92) (P = .03). Reasons for not being vaccinated were primarily lack of information, perception of own good health, and fear of adverse reactions., Conclusions: Influenza and pneumococcal vaccine uptakes were suboptimal among Danish WLP and KTR. Increased awareness about guidelines and physicians´ education are warranted., (© 2020 Wiley Periodicals LLC.)

Nephrogenic diabetes insipidus (NDI) is characterized by renal resistance to the antidiuretic hormone arginine vasopressin (AVP), which leads to polyuria, plasma hyperosmolarity, polydipsia, and impaired quality of living. Inherited forms are caused by X-linked loss-of-function mutations in the gene encoding the vasopressin 2 receptor (V2R) or autosomal recessive/dominant mutations in the gene encoding aquaporin 2 (AQP2). A common acquired form is lithium-induced NDI. AVP facilitates reabsorption of water through increased abundance and insertion of AQP2 in the apical membrane of principal cells in the collecting ducts. In X-linked NDI, V2R is dysfunctional, which leads to impaired water reabsorption. These patients have functional AQP2, and thus the challenge is to achieve AQP2 membrane insertion independently of V2R. The current treatment is symptomatic and is based on distally acting diuretics (thiazide or amiloride) and cyclooxygenase inhibitors (indomethacin). This mini-review covers published data from trials in preclinical in vivo models and a few human intervention studies to improve NDI by more causal approaches. Promising effects on NDI in preclinical studies have been demonstrated by the use of pharmacological approaches with secretin, Wnt5a, protein kinase A agonist, fluconazole, prostaglandin E 2 EP2 and EP4 agonists, statins, metformin, and soluble prorenin receptor agonists. In patients, only casuistic reports have evaluated the effect of statins, phosphodiesterase inhibitors (rolipram and sildenafil), and the guanylate cyclase stimulator riociguat without amelioration of symptoms. It is concluded that there is currently no established intervention that causally improves symptoms or quality of life in patients with NDI. There is a need to collaborate to improve study quality and conduct formal trials.

This review describes the ScandiaTransplant Kidney Exchange Programme and the background of renal exchange programmes gaining popularity worldwide, possibilities and limitations of the programmes, the ethical aspects and perspectives. The first kidney exchanges between Danish and Swedish countries were performed in 2019, and until now 23 exchanges and transplantations have been performed. All surgical procedures have been performed simultaneously and/or coordinated at different hospitals in Scandinavia, and the kidney grafts were transported between the participating units.

Background: Low-intensity shockwave therapy (LI-SWT) is suggested as a therapy for promoting tissue regeneration. In pigs, it was recently found that LI-SWT improved renal function after ischaemic injury. Our objectives were to study glomerular filtration rate (GFR) and albuminuria in diabetic nephropathy (DN) after treatment with LI-SWT. The present pilot study reports on the clinical safety of LI-SWT in DN., Methods: A total of 14 patients with diabetes mellitus and Stage 3 chronic kidney disease were recruited for this prospective, one-arm Phase 1 study. The patients were treated with six sessions of LI-SWT during a 3-week period. At each session, 3000 shockwaves were applied to each kidney with 0.265 mJ/mm2, extended focal size and 4 Hz. Follow-up visits were performed at 1, 3 and 6 months., Results: In general, the treatment was well tolerated. Transient macroscopic haematuria was observed in three patients immediately after LI-SWT. The majority of patients experienced lower back tenderness lasting up to 2 days after treatment. There was no need for analgesic treatment. LI-SWT showed no negative effect on GFR and albuminuria. At baseline, median (interquartile range) GFR was 33.5 mL/min/1.73 m2 (27.8-43.8) compared with 36.0 mL/min/1.73 m2 (27.5-52.0) at 6 months follow-up. In parallel, median albuminuria was 256 mg/24 h (79-619) at baseline and tended to decrease to 137 mg/24 h (41-404) 6 months after LI-SWT. There was no statistical difference between baseline and follow-up results., Conclusions: LI-SWT is a safe treatment for DN. Inclusion of more patients is needed to determine whether LI-SWT can improve renal functional outcomes., (© The Author(s) 2018. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

This article describes the Scandinavian expansion of the previously described kidney exchange program STEP, and the first two exchanges that were performed between two Scandinavian countries late in 2019. All surgical procedures were performed simultaneously and/or coordinated at different hospitals in Scandinavia and the kidney grafts were transported between the participating units. Four weeks after surgery, all recipients had a good and stable kidney function and all donors had recovered.

Kidney transplantation is the treatment of choice for patients with end-stage renal disease, and leads to everyday self-management of this chronic condition. This article aims to provide documentation for a participatory design study of a telehealth solution to improve the kidney transplantation process, and to identify the impact from the different participants in the participatory design study. Through a participatory design approach, a smartphone application (app) was developed for the entire kidney transplantation process together with a workflow for post-transplantation follow-up. A core element in participatory design is user involvement. By way of workshops and laboratory tests, the telehealth solution was developed in close cooperation with patients, their families, healthcare professionals, kidney association representatives, and Information Technology designers. The participatory design approach means that the telehealth solution was designed to be functional in a clinical setting, address patients' needs, and support their self-management.

Aim: To explore patients' and healthcare professionals' experiences of using a telehealth solution developed to improve follow-up after kidney transplantation., Background: Transplantation is the treatment of choice whenever feasible for patients with end-stage kidney disease. However, it implies lifelong adherence of self-monitoring, medicine and other restrictions to ensure successful outcomes. Based on user involvement, a telehealth solution was developed to support patients and healthcare professionals post-transplantation., Design: An explorative qualitative study with a phenomenological-hermeneutic approach., Methods: The developed app and workflow for follow-up were tested by patients and healthcare professionals and evaluated with interviews. In total, 16 patients and 20 healthcare professionals participated. Individual interviews were conducted with the patients, four nurses participated in two sets of interviews, and 16 doctors participated in a focus group. Data were analysed with inspiration from Ricoeur's theory of interpretation, on three levels: Naïve reading, structural analysis and critical interpretation and discussion. The COREQ checklist was applied in reporting the study., Results: Three themes emerged: Challenging conditions for training sessions, telehealth improves patient reflection and collaboration, and telehealth gives patients a voice in consultations. In a challenging time, post-transplantation patients found the app easy to use; it facilitated support and reflection on how to manage. It also supported both patients and healthcare professionals at follow-up consultations in terms of enhanced preparation, improved dialogue and enabling consultations by phone., Conclusion: The study showed that patients and healthcare professionals found the app and workflow valuable and easy to use. The Patient Data feature in the app has potential as a communication tool. However, adjustments and further investigations are needed to develop the solution., Relevance to Clinical Practice: The potential of telehealth brings new opportunities to provide treatment and care to newly transplanted patients. Telehealth can support both patients and health professionals by improving dialogue and collaboration., (© 2019 John Wiley & Sons Ltd.)

Renal transplantation is the preferred treatment of end stage renal disease, but allograft survival is limited by the development of interstitial fibrosis and tubular atrophy in response to various stimuli. Much effort has been put into identifying new protein markers of fibrosis to support the diagnosis. In the present work, we performed an in-depth quantitative proteomics analysis of allograft biopsies from 31 prevalent renal transplant patients and correlated the quantified proteins with the volume fraction of fibrosis as determined by a morphometric method. Linear regression analysis identified four proteins that were highly associated with the degree of interstitial fibrosis, namely Coagulation Factor XIII A chain (estimate 18.7, adjusted p < 0.03), Uridine Phosphorylase 1 (estimate 19.4, adjusted p < 0.001), Actin-related protein 2/3 subunit 2 (estimate 34.2, adjusted p < 0.05) and Cytochrome C Oxidase Assembly Factor 6 homolog (estimate -44.9, adjusted p < 0.002), even after multiple testing. Proteins that were negatively associated with fibrosis ( p < 0.005) were primarily related to normal metabolic processes and respiration, whereas proteins that were positively associated with fibrosis ( p < 0.005) were involved in catabolic processes, cytoskeleton organization and the immune response. The identified proteins may be candidates for further validation with regards to renal fibrosis. The results support the notion that cytoskeleton organization and immune responses are prevalent processes in renal allograft fibrosis.

The present study tested the hypotheses that nephrotic syndrome (NS) leads to renal K + loss because of augmented epithelial Na + channel (ENaC) activity followed by downregulation of renal K + secretory pathways by suppressed aldosterone. The hypotheses were addressed by determining K + balance and kidney abundance of K + and Na + transporter proteins in puromycin aminonucleoside (PAN)-induced rat nephrosis. The effects of amiloride and angiotensin II type 1 receptor and mineralocorticoid receptor (MR) antagonists were tested. Glucocorticoid-dependent MR activation was tested by suppression of endogenous glucocorticoid with dexamethasone. Urine and plasma samples were obtained from pediatric patients with NS in acute and remission phases. PAN-induced nephrotic rats had ENaC-dependent Na + retention and displayed lower renal K + excretion but elevated intestinal K + secretion that resulted in less cumulated K + in NS. Aldosterone was suppressed at day 8 . The NS-associated changes in intestinal, but not renal, K + handling responded to suppression of corticosterone, whereas angiotensin II type 1 receptor and MR blockers and amiloride had no effect on urine K + excretion during NS. In PAN-induced nephrosis, kidney protein abundance of the renal outer medullary K + channel and γ-ENaC were unchanged, whereas the Na + -Cl - cotransporter was suppressed and Na + -K + -ATPase increased. Pediatric patients with acute NS displayed suppressed urine Na + -to-K + ratios compared with remission and elevated plasma K + concentration, whereas fractional K + excretion did not differ. Acute NS is associated with less cumulated K + in a rat model, whereas patients with acute NS have elevated plasma K + and normal renal fractional K + excretion. In NS rats, K + balance is not coupled to ENaC activity but results from opposite changes in renal and fecal K + excretion with a contribution from corticosteroid MR-driven colonic secretion.

Aim: Activation of sodium reabsorption by urinary proteases has been implicated in sodium retention associated with nephrotic syndrome. The study was designed to test the hypothesis that nephrotic proteinuria in mice after conditional deletion of podocin leads to urokinase-dependent, amiloride-sensitive plasmin-mediated sodium and water retention., Methods: Ten days after podocin knockout, urine and faeces were collected for 10 days in metabolic cages and analysed for electrolytes, plasminogen, protease activity and ability to activate γENaC by patch clamp and western blot. Mice were treated with amiloride (2.5 mg kg -1 for 2 days and 10 mg kg -1 for 2 days) or an anti-urokinase-type plasminogen activator (uPA) targeting antibody (120 mg kg -1 /24 h) and compared to controls., Results: Twelve days after deletion, podocin-deficient mice developed significant protein and albuminuria associated with increased body wt, ascites, sodium accumulation and suppressed plasma renin. This was associated with increased urinary excretion of plasmin and plasminogen that correlated with albumin excretion, urine protease activity co-migrating with active plasmin, and the ability of urine to induce an amiloride-sensitive inward current in M1 cells in vitro. Amiloride treatment in podocin-deficient mice resulted in weight loss, increased sodium excretion, normalization of sodium balance and prevention of the activation of plasminogen to plasmin in urine in a reversible way. Administration of uPA targeting antibody abolished urine activation of plasminogen, attenuated sodium accumulation and prevented cleavage of γENaC., Conclusions: Nephrotic range glomerular proteinuria leads to urokinase-dependent intratubular plasminogen activation and γENaC cleavage which contribute to sodium accumulation., (© 2019 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.)

Kidney transplantation is associated with increased cardiovascular risk. Endothelial dysfunction and vascular inflammation contribute to negative outcome. In experimental models, mineralocorticoid receptor antagonists improved endothelial function and reduced inflammation. The present study tested the hypothesis that the mineralocorticoid receptor antagonist spironolactone improves endothelial function and reduces vascular inflammation in renal transplant patients. Eighty prevalent renal transplant patients from an ongoing, double-blind randomized placebo-controlled trial were included. Paired plasma samples before and after 1 yr of treatment ( n = 39 in the spironolactone-treated group and 41 in the placebo-treated group) were used to determine markers of endothelial dysfunction (nitrite, nitrate, cGMP, arginine, citrulline, ornithine, asymmetric dimethylarginine, symmetric dimethylarginine, N -monomethyl-l-arginine, von Willebrand factor, tissue-type plasminogen activator antigen, and plasminogen activator inhibitor 1 antigen) and markers of inflammation (intercellular adhesion molecule, vascular adhesion molecule, high-sensitivity C-reactive protein, and serum amyloid protein A). The median time since the transplantation was 4.6 (0.12-22.3) yr in the spironolactone-treated group and 2.1 (0.17-13.9) yr in the placebo-treated group ( G -monomethyl-l-arginine, von Willebrand factor, tissue-type plasminogen activator antigen, and plasminogen activator inhibitor 1 antigen) and markers of inflammation (intercellular adhesion molecule, vascular adhesion molecule, high-sensitivity C-reactive protein, and serum amyloid protein A). The median time since the transplantation was 4.6 (0.12-22.3) yr in the spironolactone-treated group and 2.1 (0.17-13.9) yr in the placebo-treated group ( P > 0.05). Spironolactone increased plasma aldosterone ( P < 0.001) and K + ( P < 0.001). Blood pressure did not change significantly. No significant differences were detected between groups in any of the measured markers of endothelial dysfunction or inflammation except in the subgroup analysis of patients with diabetes, where spironolactone decreased nitrite compared with placebo. In this study, mineralocorticoid receptor antagonism did not improve biomarkers of endothelial dysfunction or vascular inflammation in prevalent renal transplant patients. Further studies are needed to evaluate the potential beneficial effect of early or late mineralocorticoid receptor antagonism on vascular outcomes in renal transplant patients.

Aim: To explore patients' and healthcare professionals' experiences and perspectives on collaboration in the kidney transplantation process., Design: A qualitative study with a phenomenological-hermeneutic approach., Method: Participant observation and interviews were conducted with 18 patients, together with a focus group with eight healthcare professionals from April 2016-January 2017. The data analysis was inspired by Ricoeur's theory., Results: While patients acknowledged that the healthcare professionals were experts, they also requested an everyday life approach to treatment and care, because both professional knowledge and everyday life experiences were needed to manage everyday life. A contrast between patients' experiences and healthcare professionals' knowledge was identified, and the empowerment approach could be a way to combine the different perspectives., Competing Interests: No conflicts of interest have been declared by the authors., (© 2019 The Authors. Nursing Open published by John Wiley & Sons Ltd.)

Background: Atypical hemolytic uremic syndrome (aHUS) is a disorder of the microvasculature with hemolytic anemia, thrombocytopenia and acute kidney injury. Nowadays, aHUS is successfully treated with eculizumab, a humanized, chimeric IgG2/4 kappa antibody, which binds human complement C5 and blocks generation of C5a and membrane-attack-complex., Case Presentation: A 25-year-old woman with end stage renal disease due to relapsing atypical hemolytic uremic syndrome had a relapse of the disease during pregnancy. She was treated with eculizumab. We measured reduced formation of the membrane-attack complex in newborn's umbilical cord vein blood using the sensitive and specific Palarasah-Nielsen-ELISA., Conclusions: Eculizumab treatment of the mother with end stage renal disease may cause reduced innate immunity which could render newborns more susceptible to infections.

Background: Prior to an ABO incompatible kidney transplantation it is important to know the recipient's pre-transplantation anti-A and/or anti-B (isoagglutinin) titer. This study determined if pre-transplantation isoagglutinin titers remained stable, over a period of 1 year, among hemodialysis patients., Method: Blood was collected four times, every 3 months from 54 hemodialysis patients (hemodialysed trice per week ≥ 6 months), and 56 healthy volunteers. Measurement of anti-A and anti-B (IgM and IgG) titers were performed on an automated solid phase analyzer. The titers were converted to log 2 titer steps (e.g., titer 32 = titer step 5)., Results: Within blood group O, mean IgG anti-A and anti-B titers were significantly higher in the hemodialysis patients (n = 22, mean titer step: anti-A: 6.4 and anti-B:4.9), compared to the healthy volunteers [n = 19, mean titer step: anti-A: 4.9 and anti-B:3.5, p = 0.02 (anti-A) and p = 0.03 (anti-B)], despite blood group O hemodialysis patients having significantly lower total plasma IgG levels (median 8.1 g/L) than healthy volunteers (11.1 g/L, p = 0.001). Neither age, nor gender determined IgG anti-A or anti-B titers. In hemodialysis patients and healthy volunteers, the upper 95% confidence limit of anti-A and anti-B titer variation (IgM and IgG) during 1 year, did not exceed 1.0 titer step in any of the ABO groups., Conclusions: Anti-A and -B titers (IgM and IgG) remained stable in both the hemodialysis patients and healthy volunteers over a period of approximately 1 year. Blood group O hemodialysis patients had, despite lower total IgG levels, significantly elevated IgG anti-A and -B titers.

Aim: To explore patients' experiences before, during and four months after kidney transplantation as a coherent process., Design: A qualitative explorative study with a phenomenological-hermeneutic approach., Methods: Participant observations and semi-structured interviews were used complementary. In total, 18 kidney recipients were included. Data were analysed in accordance with Ricoeur's theory of interpretation, on three levels: naïve reading, structural analysis and critical interpretation and discussion., Results: Three themes emerged: waiting time and hope during everyday life, transformation during the kidney transplantation process and towards a new everyday life with positive prospects. Going through the kidney transplantation process was challenging for the patients. Everyday life was affected through the process, and the patients had to balance the associated challenges like hope, positive prospects and health-related issues., Competing Interests: No conflicts of interest have been declared by the authors.

Albuminuria predicts adverse renal outcome in kidney transplant recipients. The present study addressed the hypothesis that albuminuria is associated with increased urine serine proteases with the ability to activate the epithelial sodium channel (ENaC) and with greater extracellular volume and higher blood pressure. In a cross-sectional design, kidney transplant recipients with ( n = 18) and without ( n = 19) albuminuria were included for office blood pressure measurements, estimation of volume status by bioimpedance, and collection of spot urine and plasma samples. Urine was analyzed for serine proteases and for the ability to activate ENaC current in vitro. Urine exosome protein was immunoblotted for prostasin and γ-ENaC protein. In the present study, it was found that, compared with nonalbuminuria (8.8 mg/g creatinine), albuminuric (1,722 mg/g creatinine) kidney transplant recipients had a higher systolic and diastolic blood pressure, despite receiving significantly more antihypertensives, and a greater urinary total plasminogen, active plasmin, active urokinase-type plasminogen activator, and prostasin protein abundance, which correlated significantly with u-albumin. Fluid overload correlated with systolic blood pressure, urinary albumin/creatinine, and plasminogen/creatinine. Urine from albuminuric kidney transplant recipients evoked a greater amiloride- and aprotinin-sensitive inward current in single collecting duct cells (murine cell line M1). γENaC subunits at 50 and 75 kDa showed increased abundance in urine exosomes from albuminuric kidney transplant recipients when compared with controls. These findings show that albuminuria in kidney transplant recipients is associated with hypertension, ability of urine to proteolytically activate ENaC current, and increased abundance of γENaC. ENaC activity could contribute to hypertension and adverse outcome in posttransplant proteinuria.

Background: The shortage of organs from deceased donors has led to more living donation. Furthermore, immunological developments have made it possible to perform kidney transplantation despite preformed antibodies against the donor organ. This has led to a broader recruitment base of living donors., Objective: The objective was to investigate experiences and considerations on becoming, and during the process of being, a living kidney donor., Materials and Methods: Interviews and participant observation were conducted before, during and after the donation. Data were analysed in accordance with Ricoeur's theory of interpretation on three levels: naïve reading, structural analysis and critical interpretation and discussion. Eighteen potential donors over the age of 18 were included., Results: Potential donors' decision to donate was based on a desire to help the recipient. At all stages of the process, donors experienced joy, dilemmas, vulnerability and hope. Rejected donors experienced frustration and disappointment. The accepted donors experienced both joy and vulnerability. Interaction between the donor and the recipient and the relatives played a significant role. The transition from being a healthy individual to being a surgical patient was an overwhelming experience., Conclusion: The process of donating a kidney and the return to everyday life involved significant experiences of joy, dilemmas, vulnerability and hope that influenced donors' lives on physical, psychological and social levels. Support and clear communication from the health professionals was essential., (© 2018 European Dialysis and Transplant Nurses Association/European Renal Care Association.)

Background: Calcineurin inhibitor induced nephrotoxicity contributes to late allograft failure in kidney transplant patients. Evidence points towards aldosterone to play a role in the development of fibrosis in multiple organs. Animal studies have indicated a beneficial effect of mineralocorticoid receptor antagonists preventing calcineurin inhibitor induced nephrotoxicity. Only few studies have explored this effect in humans. The objective of this study is to evaluate the effect of spironolactone on glomerular filtration rate and fibrosis in kidney transplant patients., Method: Prospective, double-blind, randomized, clinical trial including 170 prevalent kidney transplant patients. Patients are randomized to spironolactone 25-50 mg/day or placebo for three years. Primary outcome is glomerular filtration rate evaluated by chrome-EDTA clearance. Secondary outcomes are 24-h protein excretion, amount of interstitial fibrosis in renal allograft biopsies, and cardiovascular events. As an exploratory outcome, we aim to identify markers of fibrosis in blood and urine., Discussion: Long term allograft survival remains a key issue in renal transplantation, partly due to calcineurin inhibitor induced nephrotoxicity. Evidence from animal- and small human studies indicate a beneficial effect of mineralocorticoid receptor antagonism on renal function and fibrosis. This study aims to test this hypothesis in a sufficiently powered randomized clinical trial. Results might influence the future management of long term allograft survival in renal transplantation., Trial Registration: ClinicalTrials.gov identifier (05/17/2012): NCT01602861 . EudraCT number (05/31/2011): 2011-002243-98.

Calcineurin inhibitors have markedly reduced acute rejection rates in renal transplantation, thus significantly improved short-term outcome. The beneficial effects are, however, tampered by acute and chronic nephrotoxicity leading to interstitial fibrosis and tubular atrophy, which impairs long-term allograft survival. The mineralocorticoid hormone aldosterone induces fibrosis in numerous organs, including the kidney. Evidence from animal models suggests a beneficial effect of aldosterone antagonism in reducing calcineurin inhibitor-induced nephrotoxicity. This review summarizes current evidence of mineralocorticoid receptor antagonism in animal models of calcineurin inhibitor-induced nephrotoxicity and the results from studies of mineralocorticoid antagonism in renal transplant patients.

Background: Using potentially out-of-group blood components, like low titer A plasma and O whole blood, in the resuscitation of trauma patients is becoming increasingly popular. However, very little is known whether the donors' anti-A and/or anti-B titers change over time and whether repeated titer measurements on the same donor are required to ensure that each donation produces a low titer product., Methods: The anti-A and/or anti-B titers were measured on 56 healthy adult volunteers (47 blood donors; nine blood center personnel) every 3 months for 12 consecutive months using an automated solid phase analyzer. The results were expressed as log2 titer steps (e.g., titer 32 = 5 titer steps)., Results: Minor variations in the average anti-A and/or anti-B titers were seen over time; the maximum individual SD in each group was 1.50 (IgG anti-A) or 1.00 (IgM anti-A, IgM, and IgG anti-B). When the SDs for the four titer measurements from all 56 volunteers were combined as appropriate, the highest overall combined SD was 0.47 titer steps for IgG anti-A. This value corresponds to a 95% confidence interval for intraindividual variation in this antibody's titer over 12 months of 0.96 titer steps. Thus, based on one measurement, an IgG anti-A with a titer step of, for example, 6 would be expected to be in the range of titer step 5 to titer step 7 over the course of 1 year with 95% probability., Conclusion: The titers of anti-A and/or anti-B among healthy adults are stable over at least 1 year. This suggests that repeated titer measurements within a year on the same donor are not necessary if donations are made at 3 months or longer intervals., Level of Evidence: Diagnostic study, level V.

The proteinase prostasin is a candidate mediator for aldosterone-driven proteolytic activation of the epithelial sodium channel (ENaC). It was hypothesized that the aldosterone-mineralocorticoid receptor (MR) pathway stimulates prostasin abundance in kidney and urine. Prostasin was measured in plasma and urine from type 2 diabetic patients with resistant hypertension (n = 112) randomized to spironolactone/placebo in a clinical trial. Prostasin protein level was assessed by immunoblotting in (1) human and rat urines with/without nephrotic syndrome, (2) human nephrectomy tissue, (3) urine and kidney from aldosterone synthase-deficient (AS -/- ) mice and ANGII- and aldosterone-infused mice, and in (4) kidney from adrenalectomized rats. Serum aldosterone concentration related to prostasin concentration in urine but not in plasma. Plasma prostasin concentration increased significantly after spironolactone compared to control. Urinary prostasin and albumin related directly and were reduced by spironolactone. In patients with nephrotic syndrome, urinary prostasin protein was elevated compared to controls. In rat nephrosis, proteinuria coincided with increased urinary prostasin, unchanged kidney tissue prostasin, and decreased plasma prostasin while plasma aldosterone was suppressed. Prostasin protein abundance in human nephrectomy tissue was similar across gender and ANGII inhibition regimens. Prostasin urine abundance was not different in AS -/- and aldosterone-infused mice. Prostasin kidney level was not different from control in adrenalectomized rats and AS -/- mice. We found no evidence for a direct relationship between mineralocorticoid receptor signaling and kidney and urine prostasin abundance. The reduction of urinary prostasin in spironolactone-treated patients is most likely the result of an improved glomerular filtration barrier function and generally reduced proteinuria.

Transplanting immunized patients requires immunological monitoring in the pretransplant phase to follow reduction of donor specific HLA antibodies (DSA) after Staphylococcus aureus protein A (SPA) immunoadsorption (IA) or therapeutic plasma exchange followed by IVIG and Rituximab administration. Pretreatment aims to significantly reduce DSA strength. The Tissue Typing Lab at Aarhus University Hospital performs immunological monitoring of approximately 150 kidney transplantation patients per year from two transplant centers. From 2012 to 2013, we experienced seven patients desensitized using SPA IA, initially presenting negative cytotoxic complement dependent (CDC) T-cell crossmatches but positive B and T cell flowcytometric crossmatch, who despite significant DSA reduction developed weakly positive CDC T-cell crossmatch shortly prior to transplantation. We hypothesised that leached SPA during IA could be the cause, as the complication was not observed in patients who received plasma exchanges. We found that the positive CDC was not donor specific and SPA column material incubated with control serum reproduced a positive CDC T-cell crossmatch. Finally, we detected leached SPA in one of the patient samples using a highly sensitive time-resolved fluorescent assay. In conclusion, the results emphasize the importance of carefully considering CDC crossmatch results subsequent to IA, before a planned transplantation is either postponed or cancelled. J. Clin. Apheresis 32:163-169, 2017. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

To investigate the impact of kidney transplantation (KTx) on insulin sensitivity affecting glucose metabolism. 9 nondiabetic patients awaiting living donor KTx were examined prior to transplantation with an oral glucose tolerance test and a 3-h hyperinsulinaemic-euglycaemic clamp. The clamp was repeated 6 months after KTx. Nine age-, gender- and body mass index (BMI)-matched individuals with normal kidney function served as controls. Endogenous glucose production and glucose disappearance rate (N = 6) were measured in a subgroup of patients with corresponding controls. Results presented as mean [range]. Two patients had pretransplant prediabetes, whereas all others had normal glucose tolerance. After KTx, average glucose infusion rate to maintain euglycaemia during clamp declined significantly from 15.1 [9.1-23.7] to 9.8 [2.8-14.6] μmol/kg/min (P < 0.01) with 20.2 [9.9-33.7] μmol/kg/min in controls. Endogenous glucose production increased from 7.0 [4.8-8.5] to 9.4 [7.4-11.8] μmol/kg/min (P < 0.05) with 7.0 [-3.8 to 10.1] μmol/kg/min in controls. Glucose disappearance rate was unchanged (18.1 [12.9-24.5] vs. 17.1 [12.2-22.7] μmol/kg/min, NS) with 22.3 [14.6-34.3] in controls. In conclusion, insulin sensitivity is reduced 6 months after KTx and characterized mainly by impaired suppression of the endogenous glucose production., (© 2016 Steunstichting ESOT.)

Background: Kidney recipients receive immunosuppression to prevent graft rejection, and long-term outcomes such as post-transplant cancer and mortality may vary according to the different protocols of immunosuppression., Methods: A national register-based historical cohort study was conducted to examine whether post-transplant cancer and all-cause mortality differed between Danish renal transplantation centres using standard immunosuppressive protocols including steroids (Centres 2, 3, 4) or a steroid-free protocol (Centre 1). The Danish Nephrology Registry, the Danish Civil Registration System, the Danish National Cancer Registry and the Danish National Patient Register were used. A historical cohort of 1450 kidney recipients transplanted in 1995-2005 was followed up with respect to post-transplant cancer and death until 31 December 2011., Results: Compared with Center 1 the adjusted post-transplant cancer risk was 6-39% lower in Centre 3 [hazard ratio (HR) 0.94, 95% confidence interval (CI) 0.67-1.32], in Centre 2 (HR 0.72, 95% CI 0.52-0.98) and in Centre 4 (HR 0.61, 95% CI 0.44-0.83). Compared with Center 1, the adjusted post-transplant mortality was 21-55% higher in Centre 4 (HR 1.21, 95% CI 0.91-1.61), in Centre 3 (HR 1.35, 95% CI 0.98-1.86) and in Centre 2 (HR 1.55, 95% CI 1.17-2.05). On average, post-transplant cancer was associated with a 4-fold increase in the risk of death (HR 4.25, 95% CI 3.36-5.38)., Conclusions: There was a tendency of a higher post-transplant cancer occurrence, but lower all-cause mortality, in the Danish transplantation centre that adhered to a standard steroid-free immunosuppressive protocol., (© The Author 2016. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Objective: Diabetic nephropathy is associated with aberrant glomerular filtration of serine proteases. The study was designed to test the hypothesis that the epithelial sodium channel is activated proteolytically by urine plasmin in diabetic nephropathy and mediates renal sodium retention., Methods: In an open-label intervention study on type 1 diabetes patients on standardized NaCl intake (200 mmol/day) with (n = 15) and without diabetic nephropathy (control, n = 12), urinary Na excretion in response to oral amiloride (20 or 40 mg/day for 2 days) was compared., Results: A total of 27 patients completed the study and nine diabetic nephropathy and eight control study participants were compliant (24-h urine Na excretion of 200 mmol ± 30%). Amiloride increased significantly total and fractional Na excretion in both groups. Total natriuresis and weight loss were significantly larger in the control group compared with diabetic nephropathy at day 1 of amiloride, whereas fractional Na excretion did not differ. Amiloride intervention increased plasma renin concentration only in diabetic nephropathy group; it reduced SBP in both groups, whereas DBP was reduced in diabetic nephropathy group only. Albuminuria was reduced significantly by amiloride in diabetic nephropathy group. Urine total amiloride concentration was not different between groups (12 ± 1 and 16 ± 1 μmol/l, respectively). Urine total plasminogen and active plasmin were reduced after amiloride in diabetic nephropathy., Conclusion: Amiloride increased renal Na excretion, reduced blood pressure, albuminuria, and total and active plasmin in urine. It is concluded that epithelial sodium channel is an attractive target to attain blood pressure control in long-term type I diabetes with no enhanced activity associated with nephropathy.

Introduction: End-stage renal disease (ESRD) is associated with increased infectious susceptibility and with reduced vaccine responses consistent with compromised humoral immunity. Whether the compromised humoral immunity is due to reduced antibody diversity (reduced somatic hypermutation [SHM]) or altered germinal center (GC) dynamics is not known. The GC-derived chemokine CXCL13 as well as peripheral T follicular helper cells (pTFH) reflect GC dynamics, but have, similar to SHM, never been characterized in relation to ESRD., Methods: Serum CXCL 13 was determined by ELISA. PTFH were flow-cytometrically defined as CD4 + CD45RA - CCR7 + CXCR5 + lymphocytes. Apoptotic lymphocyte subsets were in addition annexin V + . SHM was determined, by next-generation sequencing and bioinformatics, as nucleotide mutations within the IgG V H (comprising the important antigen-binding domains of IgG, CDR1 , and CDR2 )., Results: Elevated CXCL13 levels characterized ESRD ( n  = 19; [median] 90 pg/ml, P  < 0.01) (controls, n  = 18; 62 pg/ml). ESRD pTFH frequencies ( n  = 19; 11.6% [of CD4 + memory T cells], P  < 0.02*, *Bonferroni corrected) (controls, n  = 22; 14.9%) and concentrations ( n  = 19; 0.03 × 10 9 /L, P  < 0.02*) (controls, n  = 22; 0.07 × 10 9 /L) were reduced. ESRD pTFH were more apoptotic ( n  = 9; 25.7%, P  = 0.04*) (controls, n  = 10; 15.9%). SHM did not discriminate between ESRD ( n  = 10; 7.4%, P  = 0.21) and controls ( n  = 10; 8.4%)., Conclusions: Elevated CXCL13 levels, reduced pTFH levels, and increased pTFH apoptosis suggest that perturbed GC dynamics, and not reduced antibody diversity, underlie the diminished vaccine responses and the compromised humoral immunity in ESRD. However, largely preserved SHM provides a rationale for pursuing vaccination in relation to ESRD.

Post-transplant lymphoproliferative disorder (PTLD) incidence is difficult to determine, mainly because both early and other lesions may go unrecognized and unregistered. Few studies have included systematic pathology review to maximize case identification and decide more accurately PTLD frequency after long-term post-transplantation follow-up. A retrospective population-based cohort study including all kidney transplant recipients at two Danish centres (1990-2011; population covered 3.1 million; 2175 transplantations in 1906 patients). Pathology reports were reviewed for all patient biopsies to identify possible PTLDs. Candidate PTLDs underwent histopathological review and classification. Seventy PTLD cases were identified in 2175 transplantations (3.2%). The incidence rate (IR) after first transplantation was 5.4 cases per 1000 patient-years (95% CI: 4.0-7.3). Most PTLDs were monomorphic (58.5%), or early lesions (21.5%). Excluding early lesions and patients <18 years, IR was 3.7 (95% CI: 2.9-5.5). Ten patients with PTLD were retransplanted, 2 developing further PTLDs. Post-transplant patient survival was inferior in patients with PTLD, while death-censored graft survival was not. Using registry data together with extensive pathological review and long follow-up, a rather high incidence of PTLD was found., (© 2016 Steunstichting ESOT.)

A steroid-free protocol for ABO-compatible renal transplantation has been used at our center since 1983. To minimize the adverse effects of steroids, we also developed a steroid sparing protocol for ABO-incompatible renal transplantation in 2008. The present study is a report of our results. A retrospective review of the first 50 ABO-incompatible renal transplantations performed at a single university center. If no immunological events occurred in the post-transplant period, prednisolone tapering was initiated approximately 3 months after transplantation. Forty-three patients completed prednisolone tapering after 289 ± 58 days. Three patients died during follow-up, and four patients lost graft function. None of these adverse events were rejection related. Eleven patients experienced rejections; seven were on prednisolone and four were after weaning from prednisolone. All patients responded well to antirejection treatment. Overall, 1-year rejection rate was 19%. One- and 3-year graft survival was 94% and 91%, respectively. One-year post-transplant median serum creatinine was 123 μmol/L. We found acceptable rejection rates, graft survival, and creatinine levels in patients undergoing ABO-incompatible renal transplantations with a steroid sparing protocol. However, a longer follow-up of a lager cohort is needed before firm conclusions can be made., (© 2015 Steunstichting ESOT.)

Background: As the number of patients with end stage kidney disease continues to rise internationally, living kidney donation remains a favourable treatment option. Long waiting times on dialysis can be avoided and short and long-term outcomes are better, when compared with deceased donor transplantation. Living kidney donation is a safe procedure for healthy individuals who have completed a rigorous screening programme. Significant experiences can occur during the recovery period., Objective: To investigate donors' experiences of donation and their recovery period, in the first three months after donation., Materials and Methods: The study took a phenomenological-hermeneutic approach. Open interviews were conducted three months after donation. Data were interpreted and discussed in accordance with Ricoeur's text interpretation theory on three levels: naïve reading, structural analysis and critical interpretation and discussion., Findings: The donation process was experienced as an 'expedition', including preparations, the operation, recovery and everyday life. Positive feelings were challenging to describe; however health troubles and vulnerability were evident. A closer relationship and a need to follow the recipient's progress implied that patient and donor felt they were a part of each other. Support from relatives was important but could also be a burden., Conclusion: The kidney donation process is experienced as being like on an expedition, involving positive feelings, vulnerability, a closer patient-donor relationship and challenges around family relationships. It is essential that nurses are aware of the complexity of the situation and focus on the impact of the process, to support and facilitate donors' needs., (© 2015 European Dialysis and Transplant Nurses Association/European Renal Care Association.)

Aim and Objectives: To investigate the perceived experiences and considerations among potential kidney transplantation donors in relation to acceptance or rejection as donors., Background: Kidney transplantations are successfully performed in all Western countries, but the prevalence of patients waiting for organs from deceased donors far exceeds the number of organs available. This shortfall has promoted donation by living donors, who enter the donation process with feelings of hope, concern and patience to be accepted or rejected for donation., Design: A phenomenological-hermeneutic approach was applied in the study., Methods: Semi-structured interviews were conducted with 16 participants. Data were interpreted and discussed in accordance with Ricoeur's theory of interpretation involving: naïve reading, structural analysis, critical interpretation and discussion., Results: Accepted donors experienced relief and delight. Reflections were made on being prepared for donation and on the risks involved. Relationships between donors and recipients became closer. Rejected donors experienced frustration and disappointment, including anxiety about the recipient's prospects. Rejected donors reflected on the reason for rejection, and this could include considerations about changes to their own lifestyle. Reactions from relatives had an impact on donors., Conclusions: The study concluded that both the accepted and rejected donors were vulnerable and in need of attention, engagement, support and care. The study draws attention to the need for healthcare professionals to be open and sensitive to the donors' descriptions of their unique experiences of being accepted or rejected for kidney donation., Relevance to Clinical Practice: Nurses should be aware that dialogue with donors, including reflections on experiences, is important to reduce and alleviate vulnerability and to give the best possible support and attention, including the opportunity to promote optimal postdonation outcomes., (© 2015 John Wiley & Sons Ltd.)

In nephrotic syndrome, aberrant glomerular filtration of plasminogen and conversion to active plasmin in preurine are thought to activate proteolytically epithelial sodium channel (ENaC) and contribute to sodium retention and edema. The ENaC blocker amiloride is an off-target inhibitor of urokinase-type plasminogen activator (uPA) in vitro. It was hypothesized that uPA is abnormally filtered to preurine and is inhibited in urine by amiloride in nephrotic syndrome. This was tested by determination of Na(+) balance, uPA protein and activity, and amiloride concentration in urine from rats with puromycin aminonucleoside (PAN)-induced nephrotic syndrome. Urine samples from 6 adult and 18 pediatric patients with nephrotic syndrome were analyzed for uPA activity and protein. PAN treatment induced significant proteinuria in rats which coincided with increased urine uPA protein and activity, increased urine protease activity, and total plasminogen/plasmin concentration and Na(+) retention. Amiloride (2 mg·kg(-1)·24 h(-1)) concentration in urine was in the range 10-20 μmol/l and reduced significantly urine uPA activity, plasminogen activation, protease activity, and sodium retention in PAN rats, while proteinuria was not altered. In paired urine samples, uPA protein was significantly elevated in urine from children with active nephrotic syndrome compared with remission phase. In six adult nephrotic patients, urine uPA protein and activity correlated positively with 24 h urine protein excretion. In conclusion, nephrotic syndrome is associated with aberrant filtration of uPA across the injured glomerular barrier. Amiloride inhibits urine uPA activity which attenuates plasminogen activation and urine protease activity in vivo. Urine uPA is a relevant target for amiloride in vivo., (Copyright © 2015 the American Physiological Society.)

Aim and Objective: To explore living kidney donors' experiences during the donor evaluation process., Background: Due to a shortage of organs for kidney transplantation from deceased donors, the living kidney donation rate has increased. The time period until transplantation is often shorter when using living donors compared to deceased donors. Although technological developments in immunology have made it possible to perform successful kidney transplants between donors and recipients, a large disparity still exists between the number of patients needing a kidney transplant and the supply of kidneys from living donors. This need has promoted donation from living kidney donors. The evaluation phase prior to donation is a crucial period in the recruitment of living kidney donors, as it ensures that donors are physically and mentally suitable for donation., Design: A qualitative study taking a phenomenological-hermeneutic approach., Methods: Data were generated using participant observation during the evaluation period and semi-structured interviews after conclusion of the evaluation. In total, 18 potential donors were included. Data were interpreted and discussed in accordance with Ricoeur's theory of interpretation: naïve reading, structural analysis, critical interpretation and discussion., Results: Feelings of hope concerning acceptance as a donor and concerns for the recipient's illness and everyday life were evident during evaluation. Donors' experiences largely depended on the quality of their communication and interaction with the healthcare professionals. In some cases, donors were supported and cared for, while in other cases, frustrations and vulnerability were evident and emotional support and attention to donors' needs were not present., Conclusion: The evaluation period for living kidney donation involves hope, vulnerability and concern. Interaction, communication and support from healthcare professionals to help donors manage this crucial phase are essential. Accordingly, the identification of donors' specific care and support needs, including physical, mental and ethical factors, is key to a positive experience., Relevance to Clinical Practice: The attention, commitment and engagement of healthcare professionals are essential elements in the identification of donors' individual needs., (© 2015 John Wiley & Sons Ltd.)

Objective: Interleukin-8 (IL-8) has been associated with ischemia reperfusion injury after renal allograft transplantation. Impaired allograft function may cause major impact on patient morbidity and health care costs. We investigated whether transcript levels in mononuclear cells including IL-8 on the first postoperative day may be involved in immediate allograft dysfunction as defined by reduced relative change in plasma creatinine at the first postoperative day., Methods: We performed a single center, prospective-cohort study of 113 patients receiving kidney transplants. Peripheral blood mononuclear cells were harvested within 24 hours after transplantation. Transcripts were measured using quantitative RT-PCR., Results: Transcript levels of IL-8 and S100A8 were significantly lower in patients with relative change in plasma creatinine less than 10% at the first postoperative day. Receiver-operator characteristic curves showed that IL-8 predicted the relative change in plasma creatinine less than 10% (area under curve (AUC), 0.80; P = 0.0007). Multivariate analyses showed that lower IL-8 transcripts, longer time on dialysis, higher recipient body mass index and deceased donor type were associated with relative change in plasma creatinine at the first postoperative day less than 10%., Conclusion: Reduced levels of IL-8 transcripts in peripheral mononuclear cells predict immediate graft dysfunction and delayed graft function.

In a 36-month, open-label, multicenter trial, 202 kidney transplant recipients were randomized at week 7 post-transplant to convert to everolimus or remain on cyclosporine: 182 were analyzed to month 36 (92 everolimus, 90 controls). Mean (SD) change in measured GFR (mGFR) from randomization to month 36 was 1.3 (14.0) ml/min with everolimus versus -1.7 (15.4) ml/min in controls (P = 0.210). In patients who remained on treatment, mean mGFR improved from randomization to month 36 by 7.9 (11.5) ml/min with everolimus (n = 37) but decreased by 1.4 (14.7) ml/min in controls (n = 62) (P = 0.001). During months 12-36, death-censored graft survival was 100%, patient survival was 98.9% and 96.7% in the everolimus and control groups, respectively, and 13.0% and 11.1% of everolimus and control patients, respectively, experienced mild biopsy-proven acute rejection (BPAR). Protocol biopsies in a limited number of on-treatment patients showed similar interstitial fibrosis progression. Donor-specific antibodies were present at month 36 in 6.3% (2/32) and 18.0% (9/50) of on-treatment everolimus and control patients with available data (P = 0.281). During months 12-36, adverse events were comparable, but discontinuation was more frequent with everolimus (33.7% vs. 10.0%). Conversion from cyclosporine to everolimus at 7 weeks post-transplant was associated with a significant benefit in renal function at 3 years when everolimus was continued., (© 2014 Steunstichting ESOT.)

Objective: Current methods do not predict the acute renal allograft injury immediately after kidney transplantation. We evaluated the diagnostic performance of urinary calprotectin for predicting immediate posttransplant allograft injury., Methods: In a multicenter, prospective-cohort study of 144 incipient renal transplant recipients, we postoperatively measured urinary calprotectin using an enzyme-linked immunosorbent assay and estimated glomerular filtration rate (eGFR) after 4 weeks, 6 months, and 12 months., Results: We observed a significant inverse association of urinary calprotectin concentrations and eGFR 4 weeks after transplantation (Spearman r =  -0.33; P<0.001). Compared to the lowest quartile, patients in the highest quartile of urinary calprotectin had an increased risk for an eGFR less than 30 mL/min/1.73 m(2) four weeks after transplantation (relative risk, 4.3; P<0.001; sensitivity, 0.92; 95% CI, 0.77 to 0.98; specificity, 0.48; 95% CI, 0.31 to 0.66). Higher urinary calprotectin concentrations predicted impaired kidney function 4 weeks after transplantation, as well as 6 months and 12 months after transplantation. When data were analyzed using the urinary calprotectin/creatinine-ratio similar results were obtained. Urinary calprotectin was superior to current use of absolute change of plasma creatinine to predict allograft function 12 months after transplantation. Urinary calprotectin predicted an increased risk both in transplants from living and deceased donors. Multivariate linear regression showed that higher urinary calprotectin concentrations and older donor age predicted lower eGFR four weeks, 6 months, and 12 months after transplantation., Conclusions: Urinary calprotectin is an early, noninvasive predictor of immediate renal allograft injury after kidney transplantation.

Background: Aberrant filtration of plasminogen from plasma and subsequent activation to plasmin in the urinary space may activate proteolytically the epithelial sodium channel, ENaC. In conditions with chronic albuminuria, this may cause hypertension. It was hypothesized that patients with type 2 diabetes mellitus (T2DM) and treatment-resistant hypertension excrete plasmin(ogen) in urine in proportion to albumin and that plasmin confers to urine the ability to activate ENaC., Method: Patients (n = 113) with T2DM and resistant hypertension, defined as systolic blood pressure (SBP) more than 130 mmHg and/or diastolic blood pressure (DBP) more than 80 mmHg despite use of at least three drugs with one diuretic and one renin-angiotensin system inhibitor, were included. Urine was analyzed for albumin, creatinine, plasmin(ogen), protease activity, and ability to activate inward current in single collecting duct cells., Results: Mean ambulatory SBP/DBP was 143 ± 1/77 ± 0.7 mmHg; HbA1c 7.35%; and eGFR 81.0 ml/min per 1.73 m (geometric means). Patients with microalbuminuria (39%) and macroalbuminuria (13%) displayed significantly elevated levels of urinary plasmin(ogen) normalized to urine creatinine compared with patients with normal excretion of albumin (48%). Urinary plasminogen correlated significantly to urine albumin. Western immunoblotting and gelatine zymography confirmed active plasmin in urine samples from patients with microalbuminuria and macroalbuminuria. Single collecting duct cells displayed significantly increased, amiloride-sensitive, inward current when superfused with urine from albuminuric patients compared with patients with normal albumin excretion. Urinary plasminogen/creatinine ratio correlated significantly with 24-h ambulatory blood pressure., Conclusion: Aberrant presence of plasmin in preurine may inappropriately activate ENaC in patients with type 2 diabetes and microalbuminuria. This may contribute to treatment-resistant hypertension.

Background: When possible, renal transplantation is the treatment of choice for patients with end-stage kidney disease. Technological developments in immunology have made it possible to perform kidney transplants between donors and recipients despite antibodies against the donor organ. This allows for a wider range of relationships between recipient and donor. We investigated experiences of, and reflections on, kidney donation among genetic and non-genetic living donors before first consultation at the transplant centre., Objective: The aim was to investigate early experiences in the process of becoming a living kidney donor (LKD)., Materials and Methods: The study was conducted within a phenomenological-hermeneutic theoretical framework. Data were generated through semi-structured interviews with 18 potential donors. Data were interpreted and discussed in accordance with the Ricoeur's text interpretation theory on the three levels of naïve reading, structural analysis and critical interpretation and discussion., Results: Two themes emerged: the decision-making process and dilemmas in decision-making. The study identifies that the decision about donation was made in relation to one's own life, family situation and in relation to the recipient-considerations that demonstrate that a range of dilemmas can occur during the decision-making process. The desire to help was prominent and was of significance in decision-making., Conclusion: The study provides insight and knowledge for the health care professionals to meet and involve donors' narratives in reflections about and modifications to clinical nursing practice. It is essential that health care professionals have an understanding and appreciation of the experiences and concerns among LKDs, and this can help in planning and providing individual nursing care and support to donors., (© 2014 European Dialysis and Transplant Nurses Association/European Renal Care Association.)

In nephrotic syndrome, plasminogen is aberrantly filtered from plasma to the urinary space and activated along the tubular system. In vitro, plasmin increases ENaC current by proteolytic cleavage of the γ-subunit. It was hypothesized that preeclampsia is associated with plasmin-dependent ability of tubular fluid to activate ENaC. Urine was sampled from 16 preeclamptic (PE) patients and 17 normotensive pregnant women (Ctrl). Urine was analyzed for plasmin(ogen), creatinine, albumin, aldosterone, Na(+), K(+), proteolytic activity, and for its effect on inward current in cortical collecting duct cells (M1 cells) by whole-cell patch clamp. In PE, urine plasmin(ogen): creatinine ratio was elevated 40-fold (geometric mean, 160 versus 4 µg/g; P<0.0001) and urine aldosterone: creatinine ratio was suppressed to 25% of Ctrl (geometric mean, 27 versus 109 µg/g; P<0.001). A significant negative correlation was found in PE between urinary plasmin(ogen) and aldosterone (P<0.05). In PE, proteolytic activity was detected at 90 to 75 kD by gelatin zymography in 14 of 16 patients and confirmed by serine protease assay. Immunoblotting showed active plasmin in PE urine. Whole-cell inward current increased in M1 cells on exposure to urine from PE (173±21%; n=6; P<0.001). The increase in current was abolished by amiloride (2 μmol/L; P<0.001), α(2)-antiplasmin (1 μmol/L; P<0.001), and heat denaturation (P<0.001). Preeclampsia is associated with urinary excretion of plasmin(ogen) and plasmin-dependent activation of ENaC by urine. Proteolytic activation of ENaC by plasmin may contribute to Na(+) retention and hypertension in preeclampsia.

Introduction: Previous studies demonstrated a 3-5-fold increased cancer risk in kidney allograft recipients compared with the general population. Our aim was to estimate cancer frequencies among kidney allograft recipients who were transplanted in 1997-2000 and who were immunosuppressed according to a more modern steroid-free standard protocol based on basixilimab, ciclosporine and mycophenolate mofetil., Material and Methods: This was a retrospective cohort study of patients receiving their first kidney allograft in 1997-2000 at Odense University Hospital, Denmark (n = 90). Histologically verified cancers were identified from a detailed search of the individual patient's medical records., Results: During an average follow-up time of 8.4 years, a total of 14 cancers were observed. The cancer incidence rate was 18.5 (95% confidence interval (CI): 11.0-31.3) per 1,000 years, and the cancer prevalence was 13.4% (95% CI: 5.6-21.2%) among survivors in 2007. The relative risk of prevalent cancer was 3.6 (95% CI: 2.0-6.5) compared with the general population. Patients with cancer had a poorer survival than patients without cancer., Conclusion: The observed cancer incidence rate and prevalence were similar to figures derived from studies performed in the earlier eras of kidney transplantation. Reducing cancer rates after kidney transplantation remains an important challenge for nephrologists., Funding: not relevant., Trial Registration: not relevant.

Purpose of Review: Activation of epithelial sodium channel (ENaC) by proteolysis appears to be relevant for day-to-day physiological regulation of channel activity in kidney and other epithelial tissues. Pathophysiogical, proteolytic activation of ENaC in kidney has been demonstrated in proteinuric disease., Recent Findings: A variation in sodium and potassium intake or plasma aldosterone changes the number of cleaved α and γ-ENaC subunits and is associated with changes in ENaC currents. The protease furin mediates intracellular cleavage, whereas the channel-activating protease prostasin (CAP-1), which is glycophosphatidylinositol-anchored to the apical cell surface, mediates important extracellular cleavage. Soluble protease activity is very low in urine under physiological conditions but rises in proteinuria. In nephrotic syndrome, the dominant soluble protease activity is plasmin, which is formed from filtered plasminogen via urokinase-type plasminogen activator. Plasmin activates ENaC directly at high concentrations and through prostasin at lower concentrations., Summary: The discovery of serine protease-mediated activation of renal ENaC in physiological and pathophysiological conditions opens the way for new understanding of the pathogenesis of proteinuric sodium retention, which may involve plasmin and present several potential new drug targets.