Contrast-enhanced US in Renal Transplant Complications: Overview and Imaging Features.

Renal transplant is the first-line treatment of end-stage renal disease. The increasing number of transplants performed every year has led to a larger population of transplant patients. Complications may arise during the perioperative and postoperative periods, and imaging plays a key role in this scenario. Contrast-enhanced US (CEUS) is a safe tool that adds additional value to US. Contrast agents are usually administered intravenously, but urinary tract anatomy and complications such as stenosis or leak can be studied using intracavitary administration of contrast agents. Assessment of the graft and iliac vessels with CEUS is particularly helpful in identifying vascular and parenchymal complications, such as arterial or venous thrombosis and stenosis, acute tubular injury, or cortical necrosis, which can lead to graft loss. Furthermore, infectious and malignant graft involvement can be accurately studied with CEUS, which can help in detection of renal abscesses and in the differentiation between benign and malignant disease. CEUS is also useful in interventional procedures, helping to guide percutaneous aspiration of collections with better delimitation of the graft boundaries and to guide renal graft biopsies by avoiding avascular areas. Potential postprocedural vascular complications, such as pseudoaneurysm, arteriovenous fistula, or active bleeding, are identified with CEUS. In addition, newer quantification tools such as CEUS perfusion are promising, but further studies are needed to approve its use for clinical purposes. ©RSNA, 2024 Supplemental material is available for this article.

Midnight Cortisol is Associated with Changes in Systolic Blood Pressure and Diabetic Neuropathy in Subjects with Type 1 Diabetes Undergoing Simultaneous Kidney-Pancreas Transplantation.

INTRODUCTION: An increased midnight cortisol (MC) has been described in end-stage kidney disease (ESKD) and type 1 diabetes (T1D). Lower circulating levels of the cytokine soluble tumor necrosis factor (TNF)-like weak inducer of apoptosis (sTWEAK) have been found in T1D and ESKD and associated with cardiovascular (CV) events in the latter. We aimed to study MC and sTWEAK in simultaneous pancreas-kidney transplant (SPKT) recipients, and the association of these markers with CV risk factors and transplant outcomes. METHODS: This was a retrospective cohort study including subjects with T1D who received a first SPKT between 2008 and 2020. MC and sTWEAK at baseline were correlated with CV risk factors and evolution 1 year after SPKT. RESULTS: We included 29 subjects (58.6% women, mean age 43.5 ± 7.5 years, diabetes duration 31.9 ± 9.4 years). Systolic blood pressure (SBP) increased directly with MC quartiles, despite similar hypertension prevalence (p < 0.05). At 1 year, antihypertensive treatment was deintensified in those in lower MC quartiles (p < 0.05). Diabetic neuropathy prevalence decreased progressively in higher cortisol quartiles (p for trend = 0.005). Low MC was associated with delayed kidney graft function (p for trend = 0.044), and high sTWEAK with kidney graft rejection (p for trend = 0.018). In multivariate analyses, MC (standardized-ß 0.505, p = 0.004) and age (standardized-ß - 0.460, p = 0.040) were independently correlated with SBP, and MC was independently associated with the presence of diabetic neuropathy (OR 0.633, 95% CI 0.425-0.944, p = 0.025), adjusted for confounders. CONCLUSIONS: In this exploratory study, lower MC was associated with a lower baseline SBP, an improvement of antihypertensive treatment 1 year after transplant, and a higher diabetic neuropathy prevalence in SPKT recipients.

Challenges in perioperative blood transfusions in kidney transplantation and the need for Patient Blood Management.

BACKGROUND: Anemia is highly prevalent in end-stage chronic kidney disease patients, increasing their risk of receiving blood transfusions during and on the days after a kidney transplant (KTx) surgery. However, there is currently a lack of data that thoroughly describes this phenomenon in this population, the associated risk factors, and how they could benefit from the application of Patient Blood Management (PBM) guidelines. MATERIALS AND METHODS: Observational study. All adult patients who received a KTx between January 1st, 2020, and December 31st, 2021, were included and followed up to six months after transplantation. Those who received a multiorgan transplant, whose data was missing in the electronic health records, and who had primary non-function were excluded. We recorded donor and recipient characteristics, cold ischemia time, preoperative hemoglobin concentration, iron status deficiency biomarkers, incidence of delayed graft function and biopsy-proven graft rejections, and graft function at discharge and 6 months after transplantation. RESULTS: We found that a high amount (39%) of KTx recipients required at least one blood transfusion during the perioperative period. And that 1) most of these patients had anemia at the time of transplantation (85.4%), 2) iron status upon admission was associated with the transfusion of more blood units (3.9 vs 2.7, p=0.019), 3) surgical reintervention (OR 7.28, 2.35-22.54) and deceased donor donation (OR 1.99, 1.24-3.21) were associated with an increased risk of transfusion, and finally, 4) there was an association between a higher number of blood units transfused and impaired kidney graft function six months after hospital discharge (1.6 vs 1.9, p=0.02). CONCLUSIONS: In conclusion, PBM guidelines should be applied to patients on the KTx deceased donor waiting list and especially those scheduled to receive a transplant from a living donor. This could potentially increase the utilization efficiency of blood products and avoid transfusion-related severe adverse effects.

Impact of robotic-assisted kidney transplantation on post-transplant infections: a case-control study.

BACKGROUND: The aim of this study was to determine the differences in the incidence, epidemiology, clinical characteristics and risk factors of infections in living donor kidney transplant recipients using robotic-assisted kidney transplantation (RAKT) and open approach. METHODS: We conducted a retrospective observational study from January 2016 to December 2019. For the risk factor analysis, a matched case-control study (1:1 ratio) was performed (robotic vs open). Control subjects were matched for living donor and time of transplantation. The data included de novo immunosuppressive regimen, delayed graft function, urological complications, acute allograft rejection and incidence, clinical features, microbiological findings and outcomes of infections. RESULTS: Ninety-four RAKT and 84 controls were included. There were no differences between groups in terms of age, gender, BMI, median days of hospitalization, immunosuppressive regimen, need for surgical urologic procedures post-transplantation, presence of urinary leak or acute allograft rejection. Thirty-five percent of all recipients analyzed presented an infection, mostly asymptomatic bacteriuria (49%), symptomatic urinary tract infection (31%) and surgical site infection (10%). Pseudomonas aeruginosa was the most frequent isolated microorganism in 67%, followed by E. coli (20%), Enterococcus faecalis (17%) and Klebsiella pneumoniae (10%). Eight percent of the microorganisms were multidrug resistant. The open kidney transplantation group presented more infections compared to RAKT (43 vs 27%, p = 0.04). After multivariate analysis, need for surgical urologic procedure post-transplantation (OR 6.2, 95% CI 1.1-35), BMI ≥ 30 (OR 3.6, 95% CI 1.5-9) and acute allograft rejection (OR 3.2, 95% CI 1.2-8.5) were associated with infection, whereas RAKT (OR 0.5, 95% CI 0.2-0.9) and the use of JJ catheter (OR 0.36, 95% CI 0.17-0.72) were protective factors. CONCLUSIONS: Infection is a frequent event in patients receiving a living donor kidney transplant. Acute allograft rejection, need for surgical urologic procedure post-transplantation and BMI were associated with infection, whereas robotic surgery was a protective factor in living donor kidney transplantation.

Living donor-gifted allograft lithiasis: surgical experience after bench surgery stone removal and follow-up.

This study presents the surgical experience and long-term outcomes of living donor kidney transplantations involving asymptomatic kidney stones, using ex vivo flexible ureterorenoscopy (f-URS) during bench surgery for stone removal. Out of 1743 living kidney donors assessed between January 2012 and October 2022, 18 (1%) were diagnosed with urolithiasis. Among them, 12 donors were rejected, and 6 were accepted for kidney donation. Stone removal was successfully performed using f-URS during bench surgery, with no immediate complications or acute rejections observed. The study analyzed six living kidney transplants, of which 4 (67%) donors and three recipients were female, and 4 (67%) donors were blood-related to the recipient. The median age for donors and recipients was 57.5 and 51.5 years, respectively. The stones, primarily located in the lower calyx, had a median size of 6 mm. The median cold ischemia time during surgery was 41.6 min, and ex vivo f-URS ensured complete stone removal in all cases. After a median follow-up of 120 months, the remaining grafts were functioning well, and no urinary stone recurrence was observed in either the recipients or living donors. The findings suggest that bench f-URS is a safe approach for managing urinary stones in kidney grafts, providing good functional outcomes without stone recurrence in selected cases.

Proposal for a Two-Tier Re-classification of Stage IV/M1 domain of Renal Cell Carcinoma into M1 ("Oligometastatic") and M2 ("Polymetastatic") subdomains: Analysis of the Registry for Metastatic Renal Cell Carcinoma (REMARCC).

Purpose: We hypothesized that two-tier re-classification of the "M" (metastasis) domain of the Tumor-Node-Metastasis (TNM) staging of Renal Cell Carcinoma (RCC) may improve staging accuracy than the current monolithic classification, as advancements in the understanding of tumor biology have led to increased recognition of the heterogeneous potential of metastatic RCC (mRCC). Methods: Multicenter retrospective analysis of patients from the REMARCC (REgistry of MetAstatic RCC) database. Patients were stratified by number of metastases into two groups, M1 (≤3, "Oligometastatic") and M2 (>3, "Polymetastatic"). Primary outcome was overall survival (OS). Secondary outcomes were cancer-specific survival (CSS). Cox-regression and Kaplan-Meier (KMA) analysis were utilized for outcomes, and receiver operating characteristic analysis (ROC) was utilized to assess diagnostic accuracy compared to current "M" staging. Results: 429 patients were stratified into proposed M1 and M2 groups (M1 = 286/M2 = 143; median follow-up 19.2 months). Cox-regression revealed M2 classification as an independent risk factor for worsened all-cause mortality (HR=1.67, p=0.001) and cancer-specific mortality (HR=1.74, p<0.001). Comparing M1-oligometastatic vs. M2-polymetastatic groups, KMA revealed significantly higher 5-year OS (36% vs. 21%, p<0.001) and 5-year CSS (39% vs. 17%, p<0.001). ROC analyses comparing OS and CSS, for M1/M2 reclassification versus unitary M designation currently in use demonstrated improved c-index for OS (M1/M2 0.635 vs. unitary M 0.500) and CSS (M1/M2 0.627 vs. unitary M 0.500). Conclusion: Subclassification of Stage "M" domain of mRCC into two clinical substage categories based on metastatic burden corresponds to distinctive tumor groups whose oncological potential varies significantly and result in improved predictive capability compared to current staging.

Ex vivo normothermic preservation of a kidney graft from uncontrolled donation after circulatory death over 73 hours.

The transplant community is focused on prolonging the ex vivo preservation time of kidney grafts to allow for long-distance kidney graft transportation, assess the viability of marginal grafts, and optimize a platform for the translation of innovative therapeutics to clinical practice, especially those focused on cell and vector delivery to organ conditioning and reprogramming. We describe the first case of feasible preservation of a kidney from a donor after uncontrolled circulatory death over a 73-h period using normothermic perfusion and analyze hemodynamic, biochemical, histological, and transcriptomic parameters for inflammation and kidney injury. The mean pressure and flow values were 71.24 ± 9.62 mmHg and 99.65 ± 18.54 mL/min, respectively. The temperature range was 36.7°C-37.2°C. The renal resistance index was 0.75 ± 0.15 mmHg/mL/min. The mean pH was 7.29 ± 0.15. The lactate concentration peak increased until 213 mg/dL at 6 h, reaching normal values after 34 h of perfusion (8.92 mg/dL). The total urine output at the end of perfusion was 1.185 mL. Histological analysis revealed no significant increase in acute tubular necrosis (ATN) severity as perfusion progressed. The expression of KIM-1, VEGF, and TGFß decreased after 6-18 h of perfusion until 60 h in which the expression of these genes increased again together with the expression of ß-catenin, Ki67, and TIMP1. We show that normothermic perfusion can maintain a kidney graft viable ex vivo for 3 days, thus allowing a rapid translation of pre-clinical therapeutics to clinical practice.

Impact of Metastasectomy on Cancer Specific and Overall Survival in Metastatic Renal Cell Carcinoma: Analysis of the REMARCC Registry.

BACKGROUND: Treatment paradigms for management of metastatic renal cell carcinoma (mRCC) are evolving. We examined impact of surgical metastasectomy on survival across in mRCC stratified by risk-group. METHODS: Multicenter retrospective analysis from the Registry of Metastatic RCC database. The cohort was subdivided utilizing Motzer criteria (favorable-, intermediate-, high-risk). Primary outcome was all-cause mortality (ACM)/overall survival (OS); secondary outcome was cancer-specific mortality (CSM)/cancer-specific survival (CSS). Impact of metastasectomy was analyzed via Cox-Regression analysis adjusting for potential prognostic variables and Kaplan-Meier analysis (KMA) within each risk-group. RESULTS: Four hundred thirty-one patients (59 favorable-risk, 274 intermediate-risk, 98 high-risk; median follow-up 27.2 months) were analyzed. Metastasectomy was performed in 22 (37%), 66 (24%), and 32 (16%) of favorable-, intermediate- and high-risk groups (P = .012). Median number of metastases at diagnosis differed significantly (favorable-risk 2, intermediate-risk 3.4, high-risk 5.1, P < .001). On Cox-regression, high-risk (HR = 1.72, P = .002) was associated with worsened ACM, while metastasectomy was associated with improved ACM (HR = 0.56, P = .005). On KMA, median OS (months) was longer with metastasectomy in favorable- (92.7 vs. 25.8, P = .003) and intermediate-risk (26.3 vs. 20.1, P = .038), but not high-risk (P = .911) groups. Metastasectomy was associated with longer CSS in favorable- (76.1 vs. 32.8, P = .004) but not intermediate- (P = .06) and high-risk (P = .595) groups. CONCLUSIONS: Metastasectomy was independently associated with improved ACM and CSM, as well as improved CSS and OS in favorable- and intermediate-risk mRCC patients. Metastasectomy may be considered as component of multimodal management strategy in favorable and intermediate-risk subgroups. In high-risk patients, metastasectomy should be deferred except in select circumstances.

Patient Experience in Pancreas-Kidney Transplantation-A Methodological Approach Towards Innovation in an Established Program.

Simultaneous pancreas-kidney transplantation (SPKT) leads to increased survival and quality of life, and is an alternative treatment for insulin-dependent diabetes mellitus and end-stage kidney disease. Due to the particularities of this population (often with multiple comorbidities) and of the surgery (only performed in a few centers), a comprehensive analysis of patients' experience along the SPKT process is crucial to improve patient care and add value to this procedure. Therefore, we applied a systematic and iterative methodology with the participation of both patients and professional teams working together to explore and identify unmet needs and value-adding steps along the transplant patient journey at an established pancreas transplant program. Four main steps (to comprehend, to explore, to experiment and to assess) led to several interventions around three major areas: Administration and logistics, information and communication, and perceived quality of assistance. As a result, both displacements to the hospital for diagnostic purposes and the time delay involved in joining the patient waiting list for transplantation were reduced in parallel to the administrative procedures. In conclusion, the methodological implementation of key organizational changes has great impact on overall patient experience. Further quantitative analysis from the patient's perspective will consolidate our program and may add new prototype service design components.

Outcomes after 20 years of experience in minimally invasive living-donor nephrectomy.

INTRODUCTION: The transperitoneal laparoscopic approach is considered the gold standard technique for living kidney donation. Other accepted laparoscopic techniques include the retroperitoneal approach, natural orifice transluminal endoscopic surgery (NOTES)-assisted, laparo-endoscopic single-site surgery (LESS), with excellent results in the donor and graft. Many studies have compared these techniques with open ones. Our objective is to describe our experience and results in minimally invasive living-donor nephrectomies (MILDN): laparoscopic, NOTES-assisted, and LESS since their introduction in March 2002. MATERIALS AND METHODS: We conducted a retrospective observational study of donors undergoing MILDN between March 2002 and March 2020. RESULTS: A total of 714 MILDNs were performed at our centre. All were completed, except for one, because of recipient death. The conventional laparoscopic approach was used in 541 cases (75.88%), NOTES in 116 (16.9%), LESS in 55 (7.7%), and one mini open (0.14%). Two-thirds of the donors were females (478 cases). The mean donor age was 52.87 years (SD 10.93). Six donors (0.8%) were diagnosed beforehand with a small renal mass, which was removed before transplantation in bench surgery. The right kidney was removed in 17.8% of cases. Warm ischaemia time was higher in the NOTES and LESS groups. We had eight conversions. The global intraoperative and postoperative complication rates were 6.8% and 4.9%, respectively. None of the donors developed renal disease during follow-up (mean 3.68 years). Five-year recipient and graft survival rates were 98.8% and 96.8%, respectively. CONCLUSIONS: MILDN techniques are safe for donors and grafts, with low complication.

Donor robotic-assisted laparoscopy for uterus transplantation.

OBJECTIVE: Uterine transplantation has proven to be a viable solution in cases of absolute uterine factor infertility. Performing uterine explant surgery is one of the most difficult gynecologic surgical challenges owing to the complexity of the uterine vascular system. The goal of this video is to demonstrate uterine explant surgery and highlight the critical anatomy involved in this procedure. DESIGN: In this video, we display, narrate, and illustrate key portions of right pelvic dissection, which was subsequently performed bilaterally to achieve hysterectomy from a living donor for the purpose of uterine transplantation. SETTING: University hospital. PATIENT(S): The donor was a 39-year-old woman, and the receptor sister suffers from Rokitansky syndrome. A careful right site pelvic dissection was visualized in this operation during a hysterectomy with the aim of performing a uterine graft implantation in a living donor (Research Ethics Committee and the Assistance Ethics Committee of Hospital Clínic de Barcelona [HCB/2016/0111] and Bioethics Committee of Catalunya Study included in ClinicalTrials.org registry [NCT04314869]). INTERVENTION(S): The donor's surgery was performed entirely using robotic surgery (DaVinci Xi, Intuitive Survival Inc.). MAIN OUTCOME MEASURE(S): Assessment of uterine graft transplant viability. RESULT(S): Good quality arterial and venous pedicles were obtained during the surgery. The difficulty of this procedure is the extensive vascular dissection that has to be done to isolate the veins that drain the uterus until the hypogastric vein. CONCLUSION(S): Pelvic anatomy dissection for obtaining the graft from the donor in uterus transplantation is complex, and robotic-assisted laparoscopic surgery may help to provide a clear and more precise visualization.

Semen sampling as a simple, noninvasive surrogate for prostate health screening.

The detection rates for prostate cancer (pCa) by invasive biopsy are high, fully justifying its use in confirmatory testing. False-positive results of prior, relatively insensitive screening tests, however, can lead to expensive and often unnecessary surgery. Several reports have suggested the potential use of the ejaculate to screen for prostate conditions. Hitherto, the potential impact of sterilization on the diagnostic potential of seminal plasma screening has not been examined. Herein, we report cellular and molecular comparisons of semen samples obtained from normal (N = 5), vasectomized (N = 5) and prostate pathology patients (N = 4; confirmed by a biopsy) that were centrifuged over 60% PureSperm cushions. Non-penetrating cells were washed prior to immunocytochemistry with prostatic epithelial cell markers including PSMA, NKX3.1 and CD24. KRT18 was used to highlight epithelial cells in these samples. RNA sequencing was then used to identify differentially expressed small RNAs associated with vasectomy and prostate pathology. Specific gene transcripts were confirmed by RT-qPCR. PMSA+/KRT18+, CD24+/KRT18+ and NKX3.1/+KRT18+ cells were observed, albeit infrequently in most processed semen samples by indirect immunocytochemistry. Targeted RT-qPCR supported their enrichment, along with their putative designation as prostatic luminal cells. Small RNAs in seminal plasma were highly heterogeneous, with tRNAs and miRNAs being the dominant forms. Hsa-miR-143 and hsa-miR-199 were among the most prominent of the differentially expressed miRNAs upregulated in samples with prostate pathology but not vasectomy. The targets of these small RNAs illustrate biological processes involved among others in transcription regulation and collagen metabolism. Our outcomes strongly support an appraisal of selected biologically meaningful small RNAs of ejaculate semen for prostate health screening. A long-term goal would be a simple, routine, noninvasive test for monitoring prostate health, potentially among younger men.

Clinical and radiological findings for small renal masses under active surveillance.

OBJECTIVE: To analyze the experience performing active surveillance (AS) of small renal masses (SRMs) in our center and to correlate the evolution of SRMs under AS with clinical and radiological findings. METHODS: Patients on AS between January 2012 until May 2020 for SRMs in our center have been included. Growth rate (GR) per year was analyzed and correlated with radiographic features. Patients with growth kinetics higher than 5mm/year during follow up were offered active treatment. RESULTS: 73 patients were included in AS: the mean age was 75.7 years, a mean initial tumour size of 21.2 mm, and a mean growth rate of 2.05 mm/year. Around 60 % had an ASA score of 3. The tumor size did not change over time in 43% of cases; in 4% we noticed a regression in size and in 52% of cases growth during follow-up (38% 1-5mm/year and 14% more than 5 mm/year). Delayed active treatment was indicated in 16 (21%) of cases. Treatment applied was as following: 2 radiofrequency ablations, 6 radical and 8 partial nephrectomies. A weak correlation was found between initial size and growth rate (r = 0.38, P = 0.02). No significant association was detected regarding any of the analyzed radiological findings and GR. With a mean follow up time of 33 months none of the patients presented metastatic progression. CONCLUSION: Active surveillance is a feasible option for management of SRMs in selected patients without jeopardizing oncological safety. In our series, no clinical or radiological characteristics for predicting tumour growth were found.

Laparoendoscopic single-site simultaneous bilateral nephrectomy: first reported case series.

Bilateral renal tumors in patients on dialysis are usually managed with bilateral nephrectomy. With traditional laparoscopy, this procedure requires the insertion of multiple trocars. Laparoendoscopic single-site surgery (LESS) uses a single umbilical incision to insert multiple instruments and is also employed for extraction of specimens. This technique appears especially useful for bilateral nephrectomy, since many access ports can be spared. We describe 5 cases of simultaneous bilateral radical nephrectomies performed at a single academic institution. We had no intraoperative complications and a mean operating time of 155 minutes. Four patients could be resected using this approach; one case was converted to a traditional laparoscopy. One case had a postoperative complication. We believe this technique is feasible, and can be accomplished with acceptable morbidity and ade-quate operative time.

Development of a Novel Risk Score to Select the Optimal Candidate for Cytoreductive Nephrectomy Among Patients with Metastatic Renal Cell Carcinoma. Results from a Multi-institutional Registry (REMARCC).

BACKGROUND: Selection of patients for upfront cytoreductive nephrectomy (CN) in metastatic renal cell carcinoma (mRCC) has to be improved. OBJECTIVE: To evaluate a new scoring system for the prediction of overall mortality (OM) in mRCC patients undergoing CN. DESIGN, SETTING, AND PARTICIPANTS: We identified a total of 519 patients with synchronous mRCC undergoing CN between 2005 and 2019 from a multi-institutional registry (Registry for Metastatic RCC [REMARCC]). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Cox proportional hazard regression was used to test the main predictors of OM. Restricted mean survival time was estimated as a measure of the average overall survival time up to 36 mo of follow-up. The concordance index (C-index) was used to determine the model's discrimination. Decision curve analyses were used to compare the net benefit from the REMARCC model with International mRCC Database Consortium (IMDC) or Memorial Sloan Kettering Cancer Center (MSKCC) risk scores. RESULTS AND LIMITATIONS: The median follow-up period was 18 mo (interquartile range: 5.9-39.7). Our models showed lower mortality rates in obese patients (p = 0.007). Higher OM rates were recorded in those with bone (p = 0.010), liver (p = 0.002), and lung metastases (p < 0.001). Those with poor performance status (<80%) and those with more than three metastases had also higher OM rates (p = 0.026 and 0.040, respectively). The C-index of the REMARCC model was higher than that of the MSKCC and IMDC models (66.4% vs 60.4% vs 60.3%). After stratification, 113 (22.0%) patients were classified to have a favorable (no risk factors), 202 (39.5%) an intermediate (one or two risk factors), and 197 (38.5%) a poor (more than two risk factors) prognosis. Moreover, 72 (17.2%) and 51 (13.9%) patients classified as having an intermediate and a poor prognosis according to MSKCC and IMDC categories, respectively, would be reclassified as having a good prognosis according to the REMARCC score. CONCLUSIONS: Our findings confirm the relevance of tumor and patient features for the risk stratification of mRCC patients and clinical decision-making regarding CN. Further prospective external validations are required for the scoring system proposed herein. PATIENT SUMMARY: Current stratification systems for selecting patients for kidney removal when metastatic disease is shown are controversial. We suggest a system that includes tumor and patient features besides the systems already in use, which are based on blood tests.

Uterine transplantation. First viable case in Southern Europe.

INTRODUCTION AND OBJECTIVES: To describe the development and characteristics living donor uterine transplantation program of the Hospital Clínic (Barcelona, Spain) and to report the first successful procedure in Southern Europe. PATIENTS AND METHODS: A 31-year-old female suffering of Rokitansky Syndrome underwent uterus transplant from her living sister, as a part of our research protocol. Before the transplant, the patient underwent an in vitro fertilization procedure and twelve embryos were obtained and cryopreserved. The uterus obtention procedure was performed entirely by robotic surgery and lasted 10h, being the main objective to obtain arterial and venous pedicles of good quality in order to ensure the vitality of the graft. The surgical procedure in the recipient was performed by laparotomy and the vascular anastomoses were performed in a terminolateral fashion, with polypropylene 8-0, the vaginal cuff of the graft was sutured to the recipient vaginal vault and the round and utero-sacral ligaments were fixed to the remaining recipient ligaments. Immunosuppressive treatment was prescribed following the protocols from other groups modified according to the solid organ transplantation protocols from our center. RESULTS: The donor and recipient were discharged without any major complications. The recipient ultrasound scan showed a normal flow in both uterine arteries and veins. A grade II rejection was treated with high dose corticoids with subsequent normal biopsies and a vaginal stricture was treated with the placement of an esophageal stent for 4 weeks. The patient had her first menstrual period 47 days after the surgery. CONCLUSIONS: The case reported here open new options in Spain for a wide group of patients that had no medical solution for a disease that deeply impairs their quality of life.

Robotic-assisted kidney transplantation in obese recipients compared to non-obese recipients: the European experience.

PURPOSE: The main objective was to compare minor (Clavien I-II) and major (Clavien ≥ III) intra- and postoperative complications of living donor robotic assisted kidney transplantation (RAKT) in obese (≥ 30 kg/m2 BMI), overweight (< 30/ ≥ 25 kg/m2 BMI) and non-overweight recipients (< 25 kg/m2 BMI). METHODS: For the present retrospective study, we reviewed the multi-institutional ERUS-RAKT database to select consecutive living donor RAKT recipients. Functional outcomes, intra- and postoperative complications were compared between obese, overweight and non-overweight recipients. RESULTS: 169 living donor RAKTs were performed, by 10 surgeons, from July 2015 to September 2018 in the 8 European centers. 32 (18.9%) recipients were obese, 66 (39.1%) were overweight and 71 (42.0%) were non-overweight. Mean follow-up was 1.2 years. There were no major intra-operative complications in either study group. Conversion to open surgery occurred in 1 obese recipient, in 2 overweight recipients and no conversion occurred in non-overweight recipients (p = 0.3). Minor and major postoperative complications rates were similar in the 3 groups. At one-year of follow-up, median eGFR was similar in all groups [54 (45-60) versus 57 (46-70) versus 63 (49-78) ml/min/1.73 m2 in obese, overweight and non-overweight recipient groups, respectively, p = 0.5]. Delayed graft function rate was similar in the 3 groups. Only the number of arteries was an independent predictive factor of suboptimal renal function at post-operative day 30 in the multivariate analysis. CONCLUSION: RAKT in obese recipients is safe, compared to non-overweight recipients and yields very good function, when it performed at high-volume referral centers by highly trained transplant teams.

B Cell-Derived Extracellular Vesicles Reveal Residual B Cell Activity in Kidney Graft Recipients Undergoing Pre-Transplant Desensitization.

Background: Living-donor kidney transplant (LDKT) recipients undergoing desensitization for Human Leukocyte Antigen (HLA)-incompatibility have a high risk of developing antibody-mediated rejection (ABMR). The purpose of the study is to evaluate if residual B cell activity after desensitization could be estimated by the presence of circulating B cell-derived extracellular vesicles (BEVs). Methods: BEVs were isolated by Sepharose-based size exclusion chromatography and defined as CD19+ and HLA-II+ extracellular vesicles. We analyzed stored serum samples from positive crossmatch LDKT recipients before and after desensitization at first post-transplant biopsy and at 12-month protocol biopsy (n = 11). Control groups were formed by hypersensitized patients who were not submitted to desensitization (n = 10) and by low-risk recipients (n = 9). A prospective validation cohort of 11 patients also included the analysis of B cells subpopulations in recipients' blood and lymph nodes recovered upon graft implantation, along with BEVs analysis before and after desensitization. Results: We found out that CD19+ and HLA-II+BEVs dropped significantly after desensitization and relapse in patients who later developed ABMR was evident. We validated these findings in a proof-of-concept prospective cohort of 6 patients who received the same desensitization protocol and also in a control group of 5 LDKT recipients. In these patients, B cell subpopulations were also studied in recipients' blood and lymph nodes that were recovered before the graft implantation. We confirmed the significant drop in BEVs after desensitization and that this paralleled the reduction in CD19+cells in lymph nodes, while in peripheral blood B cells, this change was almost undetectable. Conclusions: BEVs reflected B cell residual activity after desensitization and this could be a valid surrogate of humoral alloreactivity in this setting.

Increasing kidney grafts for transplantation.

INTRODUCTION: The current pool of organs available for transplantation does not cover requirements, for this reason non-standard risk donors need to be incorporated into the pool. In this way, donors with small renal tumour are considered for transplantation after bench tumour excision. The aim of our study was to analyse our experience in using these grafts for transplantation. MATERIALS AND METHODS: Retrospective analysis from our prospective accrued database of donors with incidental renal mass used for kidney transplantation between January 2007 and August 2018. RESULTS: Twenty kidney transplantations were performed, thirteen cases received the affected kidney (after tumour removal) and seven the contralateral kidney; from six living and eleven deceased donors. Donor and recipient median age was 58 years (range 22-82) and 56.5 years (range 38-74), respectively. Mean tumour diameter was 12.7 mm (SD 9.5). Tumours resulted in two benign lesions and fifteen renal cell carcinoma. Surgical margins were negative. Two cases presented with bleeding after reperfusion was solved without repercussion. One case presented with immediate vein thrombosis. None of them present delayed graft function. After a 69 month follow-up none of the donors or the recipients presented tumour recurrence. CONCLUSIONS: Kidneys with small incidental tumours seem to be a good option for kidney transplantation in selected patients after bench surgery excision with good functional and oncologic results. More studies and longer follow-up are needed to confirm these results.