Urine-derived renal epithelial cells isolated after kidney transplant are sensitive to neutrophil gelatinase-associated lipocalin exposure during in vitro culture.

Urine-derived renal epithelial cells (URECs) are highly voided after kidney transplant and express typical kidney markers, including markers of kidney epithelial progenitor cells. Recently URECs have shown promising immunomodulatory properties when cultured with Peripheral Blood Mononuclear Cells (PBMCs), promoting an increase in the T regulatory cells. In vivo, kidney cells are highly exposed to damage associated molecules during both acute and chronic kidney injury. Neutrophil gelatinase-associated lipocalin (NGAL) is one of the most -known early marker of acute and chronic kidney damage. However, its role on the evolution of renal damage has not yet been fully described, nor has its impact on the characteristics of renal-derived cells during in vitro culture. The aim of this study is to investigate the effect of NGAL on the characteristics of URECs isolated after kidney transplant, by exposing these cells to the treatment with NGAL during in vitro culture and evaluating its effect on UREC viability, proliferation, and immunomodulatory potential. The exposure of URECs to NGAL reduced their viability and proliferative capacity, promoting the onset of apoptosis. The immunomodulatory properties of URECs were partially inhibited by NGAL, without affecting the increase of Treg cells observed during UREC-PBMCs coculture. These results suggest that the exposure to NGAL may compromise some features of kidney stem and specialized cell types, reducing their viability, increasing apoptosis, and partially altering their immunomodulatory properties. Thus, NGAL could represent a target for approaches acting on its inhibition or reduction to improve functional recovery.

"Eculizumab First" in the Management of Posttransplant Thrombotic Microangiopathy.

Introduction: Posttransplant thrombotic microangiopathy (PT-TMA) is an uncommon event that characterizes approximately 3% to 14% of kidney transplants (KTs), and that is associated with a higher risk of delayed graft function and graft loss. PT-TMA occurs more frequently within the first 3 months after transplant and can be a manifestation of de novo disease or the recurrence of previous atypical hemolytic uremic syndrome (aHUS). Abnormalities in complement regulation genes could explain the increased susceptibility of some patients to PT-TMA. Eculizumab is a humanized monoclonal antibody that inhibits the formation of the membrane attack complex C5b-9. The aim of this study is to evaluate the efficacy of eculizumab as treatment for PT-TMA. Methods: We retrospectively analyzed clinical records of 45 KT patients who received eculizumab immediately after the clinical diagnosis of PT-TMA. Results: Kidney biopsy was performed in 91.1% of patients, and complement genetic study was performed in 64.4%. Of the kidney biopsies, 85.4% showed signs of TMA; genetic analysis revealed 1 pathogenetic variant, 2 variants of uncertain significance, 1 likely benign variant, 8 risk polymorphisms, and 27 risk haplotypes. After 2 weeks from the treatment starting, hemoglobin and platelets significantly increased. A remarkable improvement in kidney function was also observed. After 6 months, 28.8% of patients had a complete renal recovery whereas 44.4% had a partial recovery. Conclusion: This is, to our knowledge, the largest series of KT patients with PT-TMA treated with eculizumab. These data suggest that eculizumab is associated with a normalization of hemolysis indices and an important and progressive improvement of graft function.

Urine-Derived Renal Epithelial Cells (URECs) from Transplanted Kidneys as a Promising Immunomodulatory Cell Population.

Kidney transplantation is a lifesaving procedure for patients with end-stage kidney disease (ESKD). Organs derived from donation after cardiac death (DCD) are constantly increasing; however, DCD often leads to ischaemia-reperfusion (IR) and Acute Kidney Injury (AKI) events. These phenomena increase kidney cell turnover to replace damaged cells, which are voided in urine. Urine-derived renal epithelial cells (URECs) are rarely present in the urine of healthy subjects, and their loss has been associated with several kidney disorders. The present study aimed to characterize the phenotype and potential applications of URECs voided after transplant. The results indicate that URECs are highly proliferating cells, expressing several kidney markers, including markers of kidney epithelial progenitor cells. Since the regulation of the immune response is crucial in organ transplantation and new immunoregulatory strategies are needed, UREC immunomodulatory properties were investigated. Co-culture with peripheral blood mononuclear cells (PBMCs) revealed that URECs reduced PBMC apoptosis, inhibited lymphocyte proliferation, increased T regulatory (Treg) cells and reduced T helper 1 (Th1) cells. URECs from transplanted patients represent a promising cell source for the investigation of regenerative processes occurring in kidneys, and for cell-therapy applications based on the regulation of the immune response.

Histological findings of diabetic kidneys transplanted in non-diabetic recipients: a case series.

BACKGROUND: Diabetic donors are recognized as a reliable source of organs, although the discard rate of kidneys is still high. Few data are available on the histological evolution of these organs especially on kidneys transplanted into non-diabetic patients who remain euglycemic. METHODS: We describe the histological evolution of ten kidney biopsies performed on non-diabetic recipients of diabetic donors. RESULTS: Mean donor age was 69 ± 7 years, 60% were males. Two donors were treated with insulin, eight with oral antidiabetic drugs. Mean recipient age was 59.9 ± 7 years, 70% were males. The pre-existing diabetic lesions identified in the pre-implantation biopsies, encompassed all histological classes, and were associated with mild IF/TA and vascular damages. The median follow-up was 59.5 [IQR 32.5-99.0] months; at follow-up, 40% of cases did not change histologic classification, two patients with class IIb downgraded to IIa or I and one with class III downgraded to IIb. Conversely, three cases showed a worsening, from class 0 to I, I to IIb or from IIa to IIb. We also observed a moderate evolution of IF/TA and vascular damages. At follow-up visit, estimated GFR was stable (50.7 mL/min vs. 54.8 at baseline) and proteinuria was mild (51.1 ± 78.6 mg/day). CONCLUSIONS: Kidneys from diabetic donors show variable evolution of the histologic features of diabetic nephropathy after transplant. This variability may be associated to recipients characteristics such as euglycemic milieu, in case of improvement, or obesity and hypertension, in case of worsening of histologic lesions.

Identification of a serum and urine extracellular vesicle signature predicting renal outcome after kidney transplant.

BACKGROUND: A long-standing effort is dedicated towards the identification of biomarkers allowing the prediction of graft outcome after kidney transplant. Extracellular vesicles (EVs) circulating in body fluids represent an attractive candidate, as their cargo mirrors the originating cell and its pathophysiological status. The aim of the study was to investigate EV surface antigens as potential predictors of renal outcome after kidney transplant. METHODS: We characterized 37 surface antigens by flow cytometry, in serum and urine EVs from 58 patients who were evaluated before, and at 10-14 days, 3 months and 1 year after transplant, for a total of 426 analyzed samples. The outcome was defined according to estimated glomerular filtration rate (eGFR) at 1 year. RESULTS: Endothelial cells and platelets markers (CD31, CD41b, CD42a and CD62P) in serum EVs were higher at baseline in patients with persistent kidney dysfunction at 1 year, and progressively decreased after kidney transplant. Conversely, mesenchymal progenitor cell marker (CD1c, CD105, CD133, SSEEA-4) in urine EVs progressively increased after transplant in patients displaying renal recovery at follow-up. These markers correlated with eGFR, creatinine and proteinuria, associated with patient outcome at univariate analysis and were able to predict patient outcome at receiver operating characteristics curves analysis. A specific EV molecular signature obtained by supervised learning correctly classified patients according to 1-year renal outcome. CONCLUSIONS: An EV-based signature, reflecting the cardiovascular profile of the recipient, and the repairing/regenerative features of the graft, could be introduced as a non-invasive tool for a tailored management of follow-up of patients undergoing kidney transplant.

Kidney transplantation in systemic sclerosis: Advances in graft, disease, and patient outcome.

Systemic sclerosis (SSc) is an immune-mediated rheumatic disease characterized by vascular abnormalities, tissue fibrosis, and inflammation. Renal disease occurring in patients with SSc may have a variable clinicopathological picture. However, the most specific renal condition associated with this disease is the scleroderma renal crisis (SRC), characterized by acute onset of renal failure and severe hypertension. SRC develops in about 20% of cases of SSc, especially in those patients with diffuse cutaneous disease. The prognosis of this condition is often negative, with a rapid progression to end-stage renal disease (ESRD). The advent of the antihypertensive angiotensin-converting enzyme inhibitors in 1980 was associated with a significant improvement in patients' survival and recovery of renal function. However, the prognosis of these patients can still be improved. The dialytic condition is associated with early death, and mortality is significantly higher than among patients undergoing renal replacement therapy (RRT) due to other conditions. Patients with SRC who show no signs of renal functional recovery despite timely blood pressure control are candidates for kidney transplantation (KT). In this review, we reported the most recent advances in KT in patients with ESRD due to SSc, with a particular overview of the risk of disease recurrence after transplantation and the evolution of other disease manifestations.

Anastomotic Pseudoaneurysm in Kidney Transplant: A Challenging Management for a Rare Entity.

PURPOSE: Anastomotic pseudoaneurysms of transplanted kidneys are a very rare complication encountered in less than 1% of cases. They may be devastating, leading to functional impairment, kidney transplantectomy, or death. Treatment has not been standardized, with open surgical repair considered the safest procedure even if it is often complicated by bleeding and graft loss. The purpose of this case report is to describe an endovascular treatment of this condition, consisting of the combination of coil embolization and arterial stenting. CASE REPORT: A 61-year-old woman developed an anastomotic pseudoaneurysm 2 months after kidney transplantation, causing acute kidney injury related to ab-extrinsic stenosis of the transplant renal artery (TRA) and external iliac artery. The pseudoaneurysm was successfully treated by coil embolization, and the arterial patency was restored by the stenting of TRA and external iliac artery. The patient completely recovered kidney function, and after a 6-month-follow-up, creatinine values were stable with normal renal perfusion. CONCLUSION: Endovascular repair through coil embolization and TRA stenting can be a safe and effective option to treat anastomotic pseudoaneurysm in kidney transplant.

Current Perspectives in ABO-Incompatible Kidney Transplant.

For a long time, ABO incompatible living donor kidney transplantation has been considered contraindicated, due to the presence of isohemagglutinins, natural antibodies reacting with non-self ABO antigens. However, as the demand for kidney transplantation is constantly growing, methods to expand the donor pool have become increasingly important. Thus, in the last decades, specific desensitization strategies for ABOi transplantation have been developed. Nowadays, these regimens consist of transient removal of preformed anti-A or anti-B antibodies by using plasmapheresis or immunoadsorption and B-cell immunity modulation by CD20+ cells depletion with rituximab, in association with maintenance immunosuppression including corticosteroids, tacrolimus and mycophenolate mofetil. The outcome in ABOi kidney transplantation have markedly improved over the years. In fact, although randomized trials are still lacking, recent meta analysis has revealed that there is no difference in terms of graft and patient's survival between ABOi and ABO compatible kidney transplant, even in the long term. However, many concerns still exist, because ABOi kidney transplantation is associated with an increased risk of bleeding and infectious complications, partly related to the effects of extracorporeal treatments and the strong immunosuppression. Thus, a continuous improvement in desensitization strategies, with the aim of minimize the immunosuppressive burden, on the basis of immune pathogenesis, antibodies titers and/or ABO blood group, is warranted. In this review, we discuss the main immune mechanisms involved in ABOi kidney transplantation, the pathogenesis of tolerance and the desensitization regimens, including immunoadsorption and plasmapheresis and the immunosuppressive protocol. Finally, we provide an overview on outcome and future perspectives in ABOi kidney transplant.

Precision Nephrology in Patients with Diabetes and Chronic Kidney Disease.

Diabetes is the leading cause of kidney failure and specifically, diabetic kidney disease (DKD) occurs in up to 30% of all diabetic patients. Kidney disease attributed to diabetes is a major contributor to the global burden of the disease in terms of clinical and socio-economic impact, not only because of the risk of progression to End-Stage Kidney Disease (ESKD), but also because of the associated increase in cardiovascular (CV) risk. Despite the introduction of novel treatments that allow us to reduce the risk of future outcomes, a striking residual cardiorenal risk has been reported. This risk is explained by both the heterogeneity of DKD and the individual variability in response to nephroprotective treatments. Strategies that have been proposed to improve DKD patient care are to develop novel biomarkers that classify with greater accuracy patients with respect to their future risk (prognostic) and biomarkers that are able to predict the response to nephroprotective treatment (predictive). In this review, we summarize the principal prognostic biomarkers of type 1 and type 2 diabetes and the novel markers that help clinicians to individualize treatments and the basis of the characteristics that predict an optimal response.

Recovering histological sections for ultrastructural diagnosis of glomerular diseases through the pop-off technique.

INTRODUCTION: Electron microscopy (EM) represents an indispensable technique for the diagnosis of kidney glomerular diseases. When dedicated tissue is not available, histological and cryostat sections can be reprocessed for EM using the pop-off technique. Here the practical value of this technique is analysed with emphasis on its accuracy in measuring basement membrane thickness and detecting immune deposits. METHODS: Ninety-four histological sections of kidney tissues fixed in Serra's solution, stained with H&E, PAS, and Masson's Trichrome; for EM analysis, the sections were recovered from either treated or untreated microscope slides through the pop-off technique. Some sections were recovered from cryosections allocated for immunofluorescence. RESULTS: The ultrastructural details were sufficiently maintained on tissues fixed with Serra's solution despite being considered disadvantageous for EM. The type of microscope slides and the time of biopsy storage did not affect the quality of section recovery. The histological stains had only moderate effects on the electron-density of the glomerular basement membrane (GBM). The pop-off technique reduced the GBM thickness when compared to the conventional EM processing but preserved the electron density of immune deposits. CONCLUSIONS: The application of the pop-off method to renal biopsy is a useful recovery method that produces limited but satisfactory results when there is no suitable material for EM. The ultrastructural morphology was retained even from tissues fixed with Serra's solution, and deposits maintained the expected electron density, however, we observed an overall thickness reduction of the GBM that could have a potential impact on thin membrane disease diagnosis.

Double Single-Side Kidney Transplants With Bench Vascular Reconstruction: A Further Challenge Beyond the Marginality Without Future Preclusions.

BACKGROUND: Double kidney transplantation allows the use of marginal kidneys with a significant improvement in the recovery of renal function expected after transplantation, although with a greater anesthesiologic and surgical risk. One-sided positioning, more cautious in the event of functional exhaustion, can be complex due to vascular anomalies. MATERIALS AND METHODS: We report the case of 2 double unilateral kidney transplants with vascular reconstructions. The first is a double kidney transplant from a 83-year-old donor. Both kidneys (score 5) had 2 arteries and the arterial patch was not usable. A cryopreserved arterial graft was used for the packaging of an arterial axis with which a single T-L anastomosis was performed; the 2 veins were also joined with the packaging of a single anastomosis. The second case is a double kidney transplant from a cadaveric donor performed on a recipient suffering from severe diffuse atheromasia. The right kidney had 2 arteries and the left kidney had 3 arteries (both score 5). The aortic patches and veins of the 2 kidneys were joined together and a single arterial and venous anastomosis was performed. RESULTS: The course has been uneventful. In both cases there were no perioperative vascular complications. CONCLUSIONS: The use of marginal organs is an increasingly common reality. Bench vascular reconstructions can further increase donation resources, safely enhancing the transplantation of already marginal organs that would otherwise not be usable and allowing the contralateral vascular axis to be kept intact.

Kidney Transplant in Fabry Disease: A Revision of the Literature.

Fabry disease is classified as a rare X-linked disease caused by a complete or partial defect of enzyme alpha-galactosidase, due to GLA gene mutations. This disorder leads to intracellular globotriaosylceramide (Gb3) deposition associated with increased Gb3 plasma levels. Most of the symptoms of the disease, involving kidneys, heart and nervous system, result from this progressive Gb3 deposition. The incidence is estimated in 1/50,000 to 1/117,000 in males. Fabry nephropathy begins with microalbuminuria and/or proteinuria, which, in the classic form, appear from childhood. Thus, a progressive decline of renal function can start at a young age, and evolve to kidney failure, requiring dialysis or renal transplantation. Enzyme replacement therapy (ERT), available since 2001 for Fabry disease, has been increasingly introduced into the clinical practice, with overall positive short-term and long-term effects in terms of ventricular hypertrophy and renal function. Kidney transplantation represents a relevant therapeutic option for Fabry nephropathy management, for patients reaching end-stage renal disease, but little is known about long-term outcomes, overall patient survival or the possible role of ERT after transplant. The purpose of this review is to analyze the literature on every aspect related to kidney transplantation in patients with Fabry nephropathy: from the analysis of transplant outcomes, to the likelihood of disease recurrence, up to the effects of ERT and its possible interference with immunosuppression.

Iloprost in Acute Post-kidney Transplant Atheroembolism: A Case Report of Two Successful Treatments.

Cholesterol embolization (CE) is a rare and alarming post-transplant complication, responsible for primary non-function (PNF) or delayed graft function (DGF). Its incidence is expected to rise due to increasingly old donors and recipients and the extended criteria for donation. Therapy with statins and steroids has not been shown to be effective, while agonism of prostaglandin I2 has been reported to be useful in systemic CE. We report two cases of acute post-transplant CE in which intravenous iloprost (0.05 mg/kg/day) was added to standard statin and steroid therapy. In the first instance, CE was due to embolization from the kidney artery resulting in embolization of the small vessels; after a long DGF and 15 days of iloprost therapy, renal function recovered. The second instance is a case of embolization from the iliac artery of the recipient, where CE manifested as a partial renal infarction. After 5 days of iloprost administration, creatinine levels improved. Iloprost acts on vasodilation and on different inflammatory pathways, improving the anti-inflammatory profile. Post-transplant CE is difficult to diagnose and, if not treated, can lead to loss of function. Iloprost added to standard therapy could be beneficial in accelerating renal function recovery immediately after transplant.

Hypothermic Oxygenated Perfusion Versus Static Cold Storage for Expanded Criteria Donors in Liver and Kidney Transplantation: Protocol for a Single-Center Randomized Controlled Trial.

BACKGROUND: Extended criteria donors (ECD) are widely utilized due to organ shortage, but they may increase the risk of graft dysfunction and poorer outcomes. Hypothermic oxygenated perfusion (HOPE) is a recent organ preservation strategy for marginal kidney and liver grafts, allowing a redirect from anaerobic metabolism to aerobic metabolism under hypothermic conditions and protecting grafts from oxidative species-related damage. These mechanisms may improve graft function and survival. OBJECTIVE: With this study, we will evaluate the benefit of end-ischemic HOPE on ECD grafts for livers and kidneys as compared to static cold storage (SCS). The aim of the study is to demonstrate the ability of HOPE to improve graft function and postoperative outcomes of ECD kidney and liver recipients. METHODS: This is an open-label, single-center randomized clinical trial with the aim of comparing HOPE with SCS in ECD kidney and liver transplantation. In the study protocol, which has been approved by the ethics committee, 220 patients (110 liver recipients and 110 kidney recipients) will be enrolled. Livers and kidneys assigned to the HOPE group undergo machine perfusion with cold Belzer solution (4-10°C) and continuous oxygenation (partial pressure of oxygen of 500-600 mm Hg). In the control group, livers and kidneys undergoing SCS are steeped in Celsior solution and stored on ice. Using the same perfusion machine for both liver and kidney grafts, organs are perfused from the start of the back-table procedure until implantation, without increasing the cold ischemia time. For each group, we will evaluate clinical outcomes, graft function tests, histologic findings, perfusate, and the number of allocated organs. Publication of the results is expected to begin in 2021. RESULTS: Dynamic preservation methods for organs from high-risk donors should improve graft dysfunction after transplantation. To date, we have recruited 108 participants. The study is ongoing, and recruitment of participants will continue until January 2020. CONCLUSIONS: The proposed preservation method should improve ECD graft function and consequently the postoperative patient outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT03837197; https://clinicaltrials.gov/ct2/show/NCT03837197 ; Archived by WebCite® at http://www.webcitation.org/76fSutT3R. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/13922.

Renal dysfunction in psoriatic patients.

Psoriasis is a common chronic inflammatory disease of the skin that is increasingly being considered as a systemic inflammatory disorder due to its association with cardiovascular, metabolic, pulmonary, renal, liver, and neurologic diseases. Renal involvement is rare but well documented and psoriasis is recognized as an independent factor for CKD and ESKD. A careful monitoring of the urinalysis and of renal function is recommended in psoriatic patients, especially those with moderate-to-severe disease. In case of pathologic findings, the execution of a renal biopsy appears necessary to make an accurate diagnosis and to establish the most appropriate therapeutic strategies to prevent the progression of kidney damage. The mechanisms of kidney involvement are different and not yet fully clarified. We present here two case reports of renal dysfunction during psoriasis. In one case, we diagnosed IgA nephropathy with particularly severe clinical presentation; in the other, an advanced kidney injury due to nephrotoxicity after prolonged CNI treatment.

Normothermic and hypothermic oxygenated perfusion for donation after circulatory death in kidney transplantation: do we pay higher risk of severe infection after transplantation?: a case report.

BACKGROUND: Normothermic and hypothermic oxygenated perfusion for donation after circulatory death in kidney transplantation are becoming popular in Italy, with the purpose of reducing the risk of primary non function and delayed graft function due to the prolonged warm ischemia time. Potential complications related to these procedures are currently under investigation and are continuously emerging with the increasing experience. Post-operative infections - in particular graft arteritis - are a rare complication but determine high risk of mortality and of graft loss. The acute onset of the arterial complications makes it very difficult to find an effective treatment, and early diagnosis is crucial for saving both patient and graft. Prevention of such infections in this particular setting are advisable. CASE PRESENTATION: We present a patient with an acute arterial rupture after transplantation of a DCD graft treated in-vivo hypothermic oxygenated perfusion. The cause was a severe arteritis of the renal artery caused by Candida krusei and Pseudomonas aeruginosa. We discussed our treatment and we compared it to the other reported series. CONCLUSION: Fungal infections in DCD transplant may be treacherous and strategies to prevent them should be advocated.

[Kidney Transplant from donors after cardiac death (DCD): monocentric experience and literature review].

Kidney transplant from donor after circulatory death (DCD) represents a valid choice to increase the incidence of renal transplantation, presenting recipients' and grafts' survival rates comparable to those from brain dead donors (DBD). In January 2016, the Transplant Referral Center in the Emilia Romagna region has started a DCD program. In the present study we report on the first 30 months of the program as far as our own Center in Bologna is concerned, and we provide a comparison with DBD transplants performed over the same period. From January 2016 to September 2018, 16 kidney transplants from 10 DCD donors (5 SCD-DCD and 5 ECD-DCD) have been performed, with two graft-loss at 12 months of follow-up, both due to renal artery rupture caused by infectious arteritis with consequent transplantectomy. Two patients died due to sepsis. Seven (44%) delay graft function (DGF) have been reported. No differences have been found between DCD and DBD in terms of kidney function (serum creatinine and eGFR evaluated at discharge, 12 and 24 months of follow-up). Kidney from marginal donors (ECD-DCD or KDPI >65%) were associated with a higher rate of DGF and worst graft function at discharge. All the predicting factors that have been analysed, including Karpinsky Score, failed to show an association with serum creatinine and eGFR at 12 and 24 months of follow up.