Cellular Immunity to Predict the Risk of Cytomegalovirus Infection in Kidney Transplantation: A Prospective, Interventional, Multicenter Clinical Trial.

BACKGROUND: Improving cytomegalovirus (CMV) immune-risk stratification in kidney transplantation is highly needed to establish guided preventive strategies. METHODS: This prospective, interventional, multicenter clinical trial assessed the value of monitoring pretransplant CMV-specific cell-mediated immunity (CMI) using an interferon-γ release assay to predict CMV infection in kidney transplantation. One hundred sixty donor/recipient CMV-seropositive (D+/R+) patients, stratified by their baseline CMV (immediate-early protein 1)-specific CMI risk, were randomized to receive either preemptive or 3-month antiviral prophylaxis. Also, 15-day posttransplant CMI risk stratification and CMI specific to the 65 kDa phosphoprotein (pp65) CMV antigen were investigated. Immunosuppression consisted of basiliximab, tacrolimus, mycophenolate mofetil, and corticosteroids in 80% of patients, whereas 20% received thymoglobulin induction therapy. RESULTS: Patients at high risk for CMV based on pretransplant CMI developed significantly higher CMV infection rates than those deemed to be at low risk with both preemptive (73.3% vs 44.4%; odds ratio [OR], 3.44 [95% confidence interval {CI}, 1.30-9.08]) and prophylaxis (33.3% vs 4.1%; OR, 11.75 [95% CI, 2.31-59.71]) approaches. The predictive capacity for CMV-specific CMI was only found in basiliximab-treated patients for both preemptive and prophylaxis therapy. Fifteen-day CMI risk stratification better predicted CMV infection (81.3% vs 9.1%; OR, 43.33 [95% CI, 7.89-237.96]). CONCLUSIONS: Pretransplant CMV-specific CMI identifies D+/R+ kidney recipients at high risk of developing CMV infection if not receiving T-cell-depleting antibodies. Monitoring CMV-specific CMI soon after transplantation further defines the CMV infection prediction risk. Monitoring CMV-specific CMI may guide decision making regarding the type of CMV preventive strategy in kidney transplantation. CLINICAL TRIALS REGISTRATION: NCT02550639.

Value of monitoring circulating donor-reactive memory B cells to characterize antibody-mediated rejection after kidney transplantation.

Antibody-mediated rejection (ABMR) is defined by specific histopathological lesions and evidence of circulating donor-specific antibodies (DSA). Although DSA are not always detectable, monitoring donor-reactive memory B cells (mBC) could identify patients at risk of developing ABMR. Peripheral donor-reactive mBC using a novel HLA B cell ELISpot assay, serum DSA, and numbers of different B cell subsets were assessed in 175 consecutive kidney transplants undergoing either for-cause or 6- and 24-month surveillance biopsies for their association with main histological lesions of ABMR and impact on allograft outcome. In 85 incident for-cause biopsies, high frequencies of donor-reactive mBC were detected in all 16 (100%) acute ABMR/DSA+ and most chronic ABMR, with or without DSA (24/30[80%] and 21/29[72.4%], respectively). In a longitudinal cohort of 90 nonsensitized patients, a progressively higher expansion of donor-reactive mBC than de novo DSA was observed at 6 and 24 months (8.8% vs 7.7% and 15.5% vs 11.1%, respectively) and accurately identified patients with ongoing subclinical ABMR (area under the curve = 0.917 and area under the curve = 0.809, respectively). An unsupervised hierarchical cluster analysis revealed a strong association between donor-reactive mBC with main fundamental allograft lesions associated with ABMR and conferred a significant deleterious impact on graft outcome. Monitoring donor-reactive mBC may be useful to further characterize humoral rejection after kidney transplantation.

The combination of CYP3A4*22 and CYP3A5*3 single-nucleotide polymorphisms determines tacrolimus dose requirement after kidney transplantation.

INTRODUCTION: Tacrolimus (Tac) has a narrow therapeutic window and shows large between-patient pharmacokinetic variability. As a result, over-immunosuppression and under-immunosuppression are frequently encountered in daily clinical practice. Unraveling the impact of genetic polymorphisms on Tac pharmacokinetics may help to refine therapy. In this study, the associations of single-nucleotide polymorphisms (SNPs) in drug-metabolizing enzymes (CYP3A) with Tac pharmacokinetics were investigated in renal transplant recipients. PARTICIPANTS AND METHODS: In a cohort of 272 kidney transplant recipients, associations between functional genetic variants (CYP3A4*22 and CYP3A5*3) and dose-adjusted predose Tac concentrations (C0) and daily doses of Tac at days 5-7 and 15 and 1, 3, 6 and 12 months after renal transplantation were evaluated. Patients were genotyped and clustered according to both CYP3A4*22 and CYP3A5*3 allelic status: poor (PM) (CYP3A4*22 carriers with CYP3A5*3/*3), intermediate (IM) (CYP3A4*1/*1 with CYP3A5*3/*3 or CYP3A4*22 carriers with CYP3A5*1 carriers) and extensive CYP3A-metabolizers (EM) (CYP3A4*1/*1 and CYP3A5*1 carriers). RESULTS: EM had an 88% lower dose-adjusted C0 compared with IM. PM had a 26% higher dose-adjusted C0 compared with IM. The percentage of patients with supratherapeutic Tac exposure (C0>15 ng/ml) was significantly higher in PM (43.5%) compared with EM (0%) at days 5-7 after transplantation (P=0.01). About 30% of EM had subtherapeutic exposure (C0<5 ng/ml) at days 5-7 after transplantation (P=0.001). CONCLUSION: The combined CYP3A4 and CYP3A5 genotype of renal transplant recipients has a major influence on the Tac dose required to reach the target exposure.

Face transplant: long-term follow-up and results of a prospective open study.

BACKGROUND: More than 30 face transplantations have been done worldwide since 2005 but no documented long-term follow-up has been reported in the literature. We aimed to answer remaining question about the long-term risks and benefits of face transplant. METHODS: In this single-centre, prospective, open study, we assessed 20 patients presenting with facial defects. Ten patients were selected, and, after three were secondarily excluded, seven were transplanted: two with neurofibromatosis 1, one with a burn, and four with self-inflicted facial gunshot injuries. We report the long-term outcomes of six face allotransplant recipients at an average of 6 years (range 3·4-9 years) after the transplantation. All admissions to hospital except for planned revisions and immunosuppressive follow-up therapy were reported as adverse events (safety endpoint). Predefined immunological, metabolic, surgical, and social integration endpoints were collected prospectively. Patients underwent quantitative health-related quality of life assessments through Short Form 36 health questionnaires. This study was registered with ClinicalTrials.gov, number NCT00527280. FINDINGS: Two of seven patients died: one at 65 days due to transplant destruction with concomitant pseudomonas infection and the second at 3·4 years after transplantation by suicide. The six patients alive at long-term follow-up presented with functional transplants. Safety endpoints were related to infection in the first month, acute rejection from 1 day to 7 years after transplantation, or side-effects of immunosuppressive therapy. Recurrent rejection episodes justified maintenance therapy with high-dose steroids at high levels in all patients at last follow-up, yet none of the patients developed diabetes. Three patients were found to have hypertension with one requiring therapy. All patients had a noticeable reduction in glomerular filtration rate. All recipients and their families accepted their transplant. Improvements in social integration and quality of life were highly variable among the patients and depended on baseline levels and psychiatric comorbidities. INTERPRETATION: These long-term results show the crucial effect of patients' social support and pre-existing psychiatric conditions on the risk-benefit ratio of facial transplantation. Careful preoperative patient selection and long-term postoperative follow-up programmes under strict institutional review board controls should be used for any future grafts of this type. FUNDING: Protocole Hospitalier de Recherche Clinique (PHRC) National.

Preformed circulating HLA-specific memory B cells predict high risk of humoral rejection in kidney transplantation.

The accurate evaluation of donor-specific antibodies (DSAs) has allowed a precise identification of sensitized patients at risk of antibody-mediated rejection (ABMR). However, the scale of the humoral response is not always fully addressed, as it excludes the complete memory B-cell (mBC) pool such as that caused by antigen-specific mBC. Using a novel B-cell ELISpot assay approach, we assessed circulating mBC frequencies against class I and II HLA antigens in highly sensitized and nonsensitized patients in the waiting list for kidney transplantation. Also, kidney transplant patients undergoing ABMR were evaluated for the presence of donor-specific mBCs both at the time of rejection and before transplantation. For this purpose, 278 target HLA-sp antigens from 70 patients were studied and compared to circulating HLA-sp antibodies. Both class I and II HLA-sp mBC frequencies were identified in highly sensitized individuals but not in nonsensitized and healthy individuals, many years after first sensitization. Also, high donor-specific mBC responses were clearly found both during ABMR and before transplantation, regardless of circulating DSA. The higher the donor-specific mBC response, the more aggressive the allograft rejection. Thus, assessing donor-specific mBC frequencies may be relevant to better refine patient alloimmune-risk stratification, and provides new insight into the mechanisms of the adaptive humoral alloimmune response taking place in kidney transplantation.

Long-term outcome of antineutrophil cytoplasmic antibody-associated small vessel vasculitis after renal transplantation.

The survival after renal transplantation of patients with antineutrophil cytoplasmic antibody (ANCA)-associated to systemic vasculitis is as good as in other diseases, although most of the reports are based on small numbers of patients. Furthermore, it is not known whether comorbidities (cardiovascular [CV] disease and cancer) are more frequent than in general population. We report our experience and the analysis of the published data on this topic. The outcome after transplantation in 49 patients with ANCA-associated small vessel vasculitis was compared with a control group. The relapse rate of vasculitis was 0.01 per patient per year. Comparison with the control patients revealed no difference in long-term outcome, CV mortality or incidence of malignancies. In the published literature, patients with ANCA at transplantation and with Wegener's granulomatosis are at greater risk of relapse. Taking our own results together with the review of the literature, we conclude that patient and graft survival rates compare favorably with those in control group that the recurrence rate is very low and that there is no increase in the incidence of cancer or in CV mortality. Patients with ANCA at transplantation and with Wegener's granulomatosis have a higher relapse rate.

Risk factors for graft loss and mortality after renal transplantation according to recipient age: a prospective multicentre study.

BACKGROUND: To describe the causes of graft loss, patient death and survival figures in kidney transplant patients in Spain based on the recipient's age. METHODS: The results at 5 years of post-transplant cardiovascular disease (CVD) patients, taken from a database on CVD, were prospectively analysed, i.e. a total of 2600 transplanted patients during 2000-2002 in 14 Spanish renal transplant units, most of them receiving their organ from cadaver donors. Patients were grouped according to the recipient's age: Group A: <40 years, Group B: 40-60 years and Group C: >60 years. The most frequent immunosuppressive regimen included tacrolimus, mycophenolate mofetil and steroids. RESULTS: Patients were distributed as follows: 25.85% in Group A (>40 years), 50.9% in Group B (40-60 years) and 23.19% in Group C (>60). The 5-year survival for the different age groups was 97.4, 90.8 and 77.7%, respectively. Death-censored graft survival was 88, 84.2 and 79.1%, respectively, and non death-censored graft survival was 82.1, 80.3 and 64.7%, respectively. Across all age groups, CVD and infections were the most frequent cause of death. The main causes of graft loss were chronic allograft dysfunction in patients <40 years old and death with functioning graft in the two remaining groups. In the multivariate analysis for graft survival, only elevated creatinine levels and proteinuria >1 g at 6 months post-transplantation were statistically significant in the three age groups. The patient survival multivariate analysis did not achieve a statistically significant common factor in the three age groups. CONCLUSIONS: Five-year results show an excellent recipient survival and graft survival, especially in the youngest age group. Death with functioning graft is the leading cause of graft loss in patients >40 years. Early improvement of renal function and proteinuria together with strict control of cardiovascular risk factors are mandatory.

Live donor kidney transplantation. Situation analysis and roadmap.

Living donor kidney transplantation (LDKT) is the best treatment option for end stage renal disease in terms of both patient and graft survival. However, figures on LDKT in Spain that had been continuously growing from 2005 to 2014, have experienced a continuous decrease in the last five years. One possible explanation for this decrease is that the significant increase in the number of deceased donors in Spain during the last years, both brain death and controlled circulatory death donors, might have generated the false idea that we have coped with the transplant needs. Moreover, a greater number of deceased donor kidney transplants have caused a heavy workload for the transplant teams. Furthermore, the transplant teams could have moved on to a more conservative approach to the information and assessment of patients and families considering the potential long-term risks for donors in recent papers. However, there is a significant variability in the LDKT rate among transplant centers and regions in Spain independent of their deceased donor rates. This fact and the fact that LDKT is usually a preemptive option for patients with advanced chronic renal failure, as time on dialysis is a negative independent factor for transplant outcomes, lead us to conclude that the decrease in LDKT depends on other factors. Thus, in the kidney transplant annual meeting held at ONT site in 2018, a working group was created to identify other causes for the decrease of LDKT in Spain and its relationship with the different steps of the process. The group was formed by transplant teams, a representative of the transplant group of the Spanish Society of Nephrology (SENTRA), a representative of the Spanish Society of Transplants (SET) and representatives of the Spanish National Transplant Organization (ONT). A self-evaluation survey that contains requests about the phases of the LDKT processes (information, donor work out, informed consent, surgeries, follow-up and human resources) were developed and sent to 33 LDKT teams. All the centers answered the questionnaire. The analysis of the answers has resulted in the creation of a national analysis of strengths, weaknesses, opportunities, threats (SWOT) of the LDKT program in Spain and the development of recommendations targeted to improve every step of the donation process. The work performed, the conclusions and recommendations provided, have been reflected in the following report: Spanish living donor kidney transplant program assessment: recommendations for optimization. This document has also been reviewed by a panel of experts, representatives of the scientific societies (Spanish Society of Urology (AEU), Spanish Society of Nephrology Nursery (SEDEN), Spanish Society of Immunology (SEI/GETH)) and the patient association ALCER. Finally, the report has been submitted to public consultation, reaching ample consensus. In addition, the transplant competent authorities of the different regions in Spainhave adopted the report at institutional level. The work done and the recommendations to optimize LDKT are summarized in the present manuscript, organized by the different phases of the donation process.

Recommendations for living donor kidney transplantation.

This Guide for Living Donor Kidney Transplantation (LDKT) has been prepared with the sponsorship of the Spanish Society of Nephrology (SEN), the Spanish Transplant Society (SET), and the Spanish National Transplant Organization (ONT). It updates evidence to offer the best chronic renal failure treatment when a potential living donor is available. The core aim of this Guide is to supply clinicians who evaluate living donors and transplant recipients with the best decision-making tools, to optimise their outcomes. Moreover, the role of living donors in the current KT context should recover the level of importance it had until recently. To this end the new forms of incompatible HLA and/or ABO donation, as well as the paired donation which is possible in several hospitals with experience in LDKT, offer additional ways to treat renal patients with an incompatible donor. Good results in terms of patient and graft survival have expanded the range of circumstances under which living renal donors are accepted. Older donors are now accepted, as are others with factors that affect the decision, such as a borderline clinical history or alterations, which when evaluated may lead to an additional number of transplantations. This Guide does not forget that LDKT may lead to risk for the donor. Pre-donation evaluation has to centre on the problems which may arise over the short or long-term, and these have to be described to the potential donor so that they are able take them into account. Experience over recent years has led to progress in risk analysis, to protect donors' health. This aspect always has to be taken into account by LDKT programmes when evaluating potential donors. Finally, this Guide has been designed to aid decision-making, with recommendations and suggestions when uncertainties arise in pre-donation studies. Its overarching aim is to ensure that informed consent is based on high quality studies and information supplied to donors and recipients, offering the strongest possible guarantees.

Costimulatory blockade with mTor inhibition abrogates effector T-cell responses allowing regulatory T-cell survival in renal transplantation.

The advent of novel immunosuppressive strategies in renal transplantation, with immunomodulatory properties, might facilitate long-term allograft survival. T-cell depletion, costimulation-blockade and mTor inhibition have been shown to favour anti-donor hyporesponsiveness. Recently, the combination of rATG, belatacept (Bela) and sirolimus (SRL) has been used in kidney transplantation, showing very low incidence of acute rejection and excellent 12-month graft and patient survival. Herein, we have analysed the 1-year evolution of memory/effector and regulatory T cells and assessed the donor-specific T-cell alloimmune response in a group of these patients and compared with others treated with a calcineurin-inhibitor(CNI)-based (rATG/tacrolimus/MMF), and two other Bela-based regimens (rATG/Bela/MMF and basiliximab/Bela/MMF/steroids). During the first year after transplantation, patients receiving rATG/Bela/SRL had significantly higher percentage of Tregs upon the memory T-cell compartment and showed a potent anti-donor suppressive activity. In an in vitro naive and memory/effector T-cell co-culture, the combination of costimulation-blockade and SRL could abrogate both antigen-specific T-cell responses as efficiently as using a CNI drug. The combination of T-cell depletion, costimulation-blockade and mTor inhibition seems to be able to allow Treg survival and inhibit donor-specific alloreactive effector immune responses after kidney transplantation in humans.

[Prophylaxis of cytomegalovirus infection in renal transplantation]. / Profilaxis de la infección por citomegalovirus en el trasplante renal.

Cytomegalovirus (CMV) infection remains a major problem in renal transplant recipients. CMV produces not only febrile syndromes and/or visceral disease but also contributes to the development of acute rejection and chronic graft failure. Valganciclovir prophylaxis has represented a major advance in controlling this infection, but late CMV infection after prophylaxis can occur, especially when universal prophylaxis is used. The use of valganciclovir prophylaxis for 200 days is more effective than prophylaxis for 100 days but does not completely prevent this problem. Prophylaxis based on the detection of CMV viremia (early prophylaxis or preemptive therapy) may prevent the development of delayed CMV disease, but has the disadvantage of requiring more intensive monitoring of viremia and does not prevent the development of viremia and its potential consequences in the long term. This article reviews current recommendations for prophylaxis of CMV disease in renal transplantation.

GESITRA-SEIMC/REIPI recommendations for the management of cytomegalovirus infection in solid-organ transplant patients.

Cytomegalovirus infection remains a major complication of solid organ transplantation. In 2005 the Spanish Transplantation Infection Study Group (GESITRA) of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) developed consensus guidelines for the prevention and treatment of CMV infection in solid organ transplant recipients. Since then, numerous publications have clarified or questioned the aspects covered in the previous document. These aspects include the situations and populations who must receive prophylaxis and its duration, the selection of the best diagnosis and monitoring technique and the best therapeutic strategy. For these reasons, we have developed new consensus guidelines to include the latest recommendations on post-transplant CMV management based on new evidence available.

Live donor kidney transplantation. Situation analysis and roadmap. / Trasplante renal de donante vivo. Análisis de situación y hoja de ruta.

Living donor kidney transplantation (LDKT) is the best treatment option for end stage renal disease in terms of both patient and graft survival. However, figures on LDKT in Spain that had been continuously growing from 2005 to 2014, have experienced a continuous decrease in the last five years. One possible explanation for this decrease is that the significant increase in the number of deceased donors in Spain during the last years, both brain death and controlled circulatory death donors, might have generated the false idea that we have coped with the transplant needs. Moreover, a greater number of deceased donor kidney transplants have caused a heavy workload for the transplant teams. Furthermore, the transplant teams could have moved on to a more conservative approach to the information and assessment of patients and families considering the potential long-term risks for donors in recent papers. However, there is a significant variability in the LDKT rate among transplant centers and regions in Spain independent of their deceased donor rates. This fact and the fact that LDKT is usually a preemptive option for patients with advanced chronic renal failure, as time on dialysis is a negative independent factor for transplant outcomes, lead us to conclude that the decrease in LDKT depends on other factors. Thus, in the kidney transplant annual meeting held at ONT site in 2018, a working group was created to identify other causes for the decrease of LDKT in Spain and its relationship with the different steps of the process. The group was formed by transplant teams, a representative of the transplant group of the Spanish Society of Nephrology (SENTRA), a representative of the Spanish Society of Transplants (SET) and representatives of the Spanish National Transplant Organization (ONT). A self-evaluation survey that contains requests about the phases of the LDKT processes (information, donor work out, informed consent, surgeries, follow-up and human resources) were developed and sent to 33 LDKT teams. All the centers answered the questionnaire. The analysis of the answers has resulted in the creation of a national analysis of strengths, weaknesses, opportunities, threats (SWOT) of the LDKT program in Spain and the development of recommendations targeted to improve every step of the donation process. The work performed, the conclusions and recommendations provided, have been reflected in the following report: Spanish living donor kidney transplant program assessment: recommendations for optimization. This document has also been reviewed by a panel of experts, representatives of the scientific societies (Spanish Society of Urology (AEU), Spanish Society of Nephrology Nursery (SEDEN), Spanish Society of Immunology (SEI/GETH)) and the patient association ALCER. Finally, the report has been submitted to public consultation, reaching ample consensus. In addition, the transplant competent authorities of the different regions in Spain have adopted the report at institutional level. The work done and the recommendations to optimize LDKT are summarized in the present manuscript, organized by the different phases of the donation process.

Presence of FoxP3+ regulatory T Cells predicts outcome of subclinical rejection of renal allografts.

Subclinical rejection (SCR) of renal allografts refers to histologic patterns of acute rejection despite stable renal function. The clinical approach to SCR is controversial; it would be helpful to identify biomarkers that could determine whether the identified cellular infiltrates were detrimental. For investigation of whether the presence of FoxP3+ regulatory T cells (Treg) could help determine the functional importance of tubulointerstitial infiltrates observed in 6-mo protocol biopsies, 37 cases of SCR were evaluated. The presence of FoxP3+ Treg discriminated harmless from injurious infiltrates, evidenced by independently predicting better graft function 2 and 3 yr after transplantation. Furthermore, the FoxP3+ Treg/CD3+ T cell ratio positively correlated with graft function at 2 yr after transplantation, suggesting that an increasing proportion of Treg within the global T cell infiltrate may facilitate renal engraftment; therefore, immunostaining for FoxP3+ Treg in patients with SCR on protocol biopsies may ultimately be useful to identify patients who may require alterations in their immunosuppressive regimens.

Combining Sensitive Crossmatch Assays With Donor/Recipient Human Leukocyte Antigen Eplet Matching Predicts Living-Donor Kidney Transplant Outcome.

Introduction: Despite the different assays available for immune-risk stratification before living-donor kidney transplantation (LDKT), the precise type and number of tests to perform remain uncertain. Methods: In a cohort of 330 consecutive LDKT patients, all of which were complement-dependent cytotoxicity (CDC)-crossmatch negative, we retrospectively analyzed the impact on main clinical outcomes of most sensitive immunoassays (complement-dependent cytotoxicity-panel-reactive antibody [CDC-PRA], flow cytometry crossmatch [FC-XM], donor-specific antibodies [DSAs], and their complement-binding capacity DSA-C3d]), together with donor/recipient HLA eplet matching. Mean follow-up was 67 months (range 24-190 months). Results: Of 330 patients, 35 (11%) showed a CDC-PRA >20%; 17 (5%) FC-XM+; 30 (9%) DSA+, 18(5%) DSA-C3d+, with low overlapping results (10 patients positive in all donor-specific tests). Unlike HLA allele compatibility, the mean number of HLA class II eplet mismatches was higher in LDKT patients with positive baseline test results. DSA-C3d+ showed higher mean fluorescence intensity (MFI) DSA, with a cut-off MFI of 6192 accurately predicting complement fixation (area under the curve = 0.85, P = 0.008). Although all assays were associated with acute rejection (AR), only DSA-C3d+ (odds ratio [OR] = 6.64, P = 0.038) or high MFI-DSA (OR = 7.54, P = 0.038) independently predicted AR. Likewise, poorly HLA class II eplet-matched patients were at higher risk for AR, particularly patients with negative baseline test results (OR = 1.14, P = 0.019). Finally, previous AR and FC-XM+/DSA+, regardless of C3d positivity, independently predicted graft loss. Conclusion: Combining FC-XM and solid-phase assays with the evaluation of donor/recipient HLA eplet mismatches, are most accurate tools for immune-risk stratification prior LDKT.

CMV-specific Cell-mediated Immunity at 3-month Prophylaxis Withdrawal Discriminates D+/R+ Kidney Transplants at Risk of Late-onset CMV Infection Regardless the Type of Induction Therapy.

BACKGROUND: Whether cytomegalovirus (CMV)-specific cell-mediated immunity (CMI) at prophylaxis cessation predicts D+/R+ kidney transplants at risk of late-onset CMV infection after receiving distinct induction therapies is still not well characterized. METHODS: We prospectively assessed CMV-specific CMI predicting late-onset CMV infection at prophylaxis withdrawal and at earlier time-points, in 96 consecutive D+/R+ patients receiving either anti-interleukin 2-receptor antibody (anti-IL2RA; n = 50) or rabbit antithymoglobulin (n = 46). CMV-specific CMI was evaluated against CMV antigens (IE-1, pp65) using an IFN-γ ELISpot assay. RESULTS: Fourteen (14.6%) of 96 patients developed late-onset CMV infection and 2 (2.1%) of 96 displayed disease. At 3 months, CMV-specific CMI frequencies were significantly lower in patients developing late-onset CMV infection (P < 0.001 for IE-1, P = 0.030 for pp65), regardless the type of induction therapy. Receiver operating characteristic curve analyses showed accurate CMV-specific CMI cutoffs (25 and 130 IFN-γ spots for IE-1 and pp65, respectively) classifying patients into high risk, intermediate risk, or low risk (log-rank = 0.006; hazard ratio, 4.084; 95% confidence interval, 1.431-11.651; P = 0.009), being IE-1 CMI the strongest predictor (odds ratio, 5.554; 95% confidence interval, 1.486-20.766; P = 0.011). Although the profound posttransplant CMV-specific CMI inhibition among rabbit antithymocyte globulin-treated patients precludes its use for risk stratification both before and early after kidney transplant, a similar proportion of at-risk patients could be identified before month 3 within anti-interleukin 2-receptor antibody-treated patients. CONCLUSIONS: Monitoring CMV-specific CMI at 3-month prophylaxis cessation discriminates kidney transplant recipient at risk of late-onset CMV infection, regardless the type of induction therapy.

Early hematopoietic microchimerism predicts clinical outcome after kidney transplantation.

BACKGROUND: The presence of a few circulating donor cells in recipient's blood was first thought to be only an epiphenomenon of solid organ transplantation, also called microchimerism, but several authors have suggested that these circulating cells may contribute to tolerance induction. This study aims to assess the rate of microchimerism after kidney transplantation and determine its influence on acute rejection in a 4-year follow-up. METHODS: A total of 84 single-kidney recipients were included for microchimerism detection and quantification 2, 6, 12, and 18 months after transplantation by specific detection of non-shared STR, VNTR, human leukocyte antigen-A, -B, -DRB1, and SRY alleles. Kinetic establishment of microchimerism was monitored in a double kidney transplanted recipient for 150 min after declamping and after 7 days. RESULTS: Microchimerism was detected in 56.2% of kidney recipients 2 months after transplantation (M2): this fell to 30.1% at 12 months. In renal calcineurin inhibitor-based immunosuppression cohort (n=73), the microchimerism-negative group (n=32) showed 37.9% biopsy-proven acute rejection (BPAR), whereas in the microchimerism-positive group (n=41), no recipient did (P<0.001). Regardless of immunosuppression, BPAR incidence was 35.6% and 4.9%, respectively (P<0.001). Multivariate study showed microchimerism as a protective factor against BPAR (odds ratio: 8.3; 95% confidence interval: 1.8 to 37.9; P = 0.006), blinding other well-known rejection-risk variables. Microchimerism M2 presence did not correlate with a multifactorial critical outcome such as late graft loss. CONCLUSION: Microchimerism was frequent after kidney transplantation and correlated with a significantly lower incidence of rejection. We propose that early microchimerism monitoring could help early detection of low rejection-risk recipients.

Trasplante renal de donante vivo. Análisis de situación y hoja de ruta / Live donor kidney transplantation. Situation analysis and roadmap

El trasplante renal de donante vivo (TRDV) es la opción terapéutica con las mejores expectativas de supervivencia para el injerto y para el paciente con insuficiencia renal terminal; sin embargo, este tipo de trasplantes ha experimentado un descenso progresivo en los últimos años en España.Entre las posibles explicaciones del descenso de actividad se encuentra la coincidencia en el tiempo con un aumento en el número de donantes renales fallecidos, tanto por muerte encefálica como por asistolia controlada, que podría haber generado una falsa impresión de ausencia de necesidad del TRDV. Además, la disponibilidad de un mayor número de riñones para trasplante habría supuesto un incremento en la carga de trabajo de los profesionales que pudiera enlentecer los procesos de donación en vida. Otro posible argumento radica en un posible cambio de actitud hacia posturas más conservadoras a la hora de informar a pacientes y a familiares acerca de esta opción terapéutica, a raíz de los artículos publicados respecto al riesgo de la donación a largo plazo. Sin embargo, existe una importantísima variabilidad en la actividad entre centros y comunidades autónomas, no explicada por el volumen de trasplante procedente de otros tipos de donante. Este dato, unido a que la indicación de donación renal en vida se realiza de manera mayoritaria en situación de enfermedad renal crónica avanzada (ERCA) y que el tiempo en diálisis es un factor pronóstico negativo respecto a la supervivencia postrasplante, permite concluir que el descenso depende además de otros factores. ... (AU)

Living donor kidney transplantation (LDKT) is the best treatment option for end stage renal disease in terms of both patient and graft survival. However, figures on LDKT in Spain that had been continuously growing from 2005 to 2014, have experienced a continuous decrease in the last five years.One possible explanation for this decrease is that the significant increase in the number of deceased donors in Spain during the last years, both brain death and controlled circulatory death donors, might have generated the false idea that we have coped with the transplant needs. Moreover, a greater number of deceased donor kidney transplants have caused a heavy workload for the transplant teams.Furthermore, the transplant teams could have moved on to a more conservative approach to the information and assessment of patients and families considering the potential long-term risks for donors in recent papers. However, there is a significant variability in the LDKT rate among transplant centers and regions in Spain independent of their deceased donor rates. This fact and the fact that LDKT is usually a preemptive option for patients with advanced chronic renal failure, as time on dialysis is a negative independent factor for transplant outcomes, lead us to conclude that the decrease in LDKT depends on other factors.Thus, in the kidney transplant annual meeting held at ONT site in 2018, a working group was created to identify other causes for the decrease of LDKT in Spain and its relationship with the different steps of the process. The group was formed by transplant teams, a representative of the transplant group of the Spanish Society of Nephrology (SENTRA), a representative of the Spanish Society of Transplants (SET) and representatives of the Spanish National Transplant Organization (ONT). ... (AU)

Steroids can be safely withdrawn from cyclosporine and mycophenolate mofetil-treated renal allograft recipients: long-term results.

BACKGROUND: Discontinuation of steroids has long been a goal of transplant teams. However, whether this strategy is associated or not with a higher risk of long-term graft loss has not been resolved. METHODS: The authors analyzed a cohort of 91 renal allograft recipients who underwent transplantation between 1993 and 1997. They were treated with cyclosporine and mycophenolate mofetil (MMF) and then had steroids withdrawn. Inclusion criteria were as follows: serum creatinine lower than 133 microM, first or second renal transplants, no or only one acute rejection episode (borderline or Ia grade), and a peak of panel reactive antibodies under 50%. Prednisone was gradually tapered off and then discontinued over a period of 2 to 4 months. RESULTS: There were no episodes of acute rejection after steroid withdrawal. Whether steroids were withdrawn before (early) or after (late) 6 months of renal transplantation did not influence outcome. By Kaplan-Meier analysis, patient survival was 93.6% and 100% at 5 years and 93.6% and 97.6% at 10 years in the early and late steroid withdrawal groups, respectively. Graft survival was 94.3% and 98.1% at 5 years and 87.6% and 82.4% at 10 years in the early and late steroid-withdrawal groups, respectively. Risk factors for graft loss in multivariate analysis were peak of panel reactive antibodies (relative risk, 1.074; 95% confidence interval, 1.017-1.134; P=0.01) and acute rejection (relative risk, 16.5; 95% confidence interval, 1.8-147; P=0.01). CONCLUSIONS: Early and late steroid withdrawal in low-immunologic-risk renal allografts treated with cyclosporine and MMF can be achieved without risk of acute rejection and with excellent long-term results.