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1.
Rev Sci Instrum ; 94(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38085054

RESUMO

Recent upgrades providing two-dimensional divertor Thomson scattering (DTS-2D) measurements of Te and ne during a DIII-D plasma shot and a thorough description of system components and their functionality are presented. This system expands the capabilities of the existing single divertor Floor measurement location by introducing seven additional laser beam path options in the poloidal plane, spanning major radii from 1.062 to 1.335 m. The system redirects ∼1 J, 50 Hz Nd:YAG laser pulses to the new beam paths within 20 ms, stepping through each path on the divertor Floor every 200 ms during a plasma shot. The laser is redirected using an ex-vessel, fast-steering mirror to one of eight in-vessel beam paths oriented underneath the vessel tiles. Up to eleven measurement positions per beam path, from -1.35 to -1.13 m below the machine midplane, are available by dynamically refocusing the ex-vessel collection fiber array using a high-speed linear stage. Current measurement positions above the divertor Shelf are retained via a hole in the fixed, in-vessel mirror, allowing laser pass through.

2.
Transpl Int ; 36: 11205, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37266028

RESUMO

Extrapolating data from early DCD (donation after circulatory death) kidney transplantation, pancreas transplants from DCD grafts were feared to have worse metabolic outcomes. Hence, we aimed to address the question of pancreas transplant alone (PTA) from DCD donors-are our concerns justified? A UK transplant registry analysis of 185 PTA performed between 2005 and 2018 was done. All early graft losses (<3 months) were excluded to allow focus on the metabolic outcomes (HbA1c, weight gain and incidence of secondary diabetic macrovascular complications). The aim was to compare the metabolic outcomes, rejection rates (including the need for steroids), patient and graft survival between DBD (Donation after brainstem death) and DCD groups. After excluding early graft losses, data from 162 PTA (DBD = 114 and DCD = 48) were analyzed. Body mass index of the donor was less in DCD group (DBD = 23.40 vs. DCD = 22.25, p = 0.006) and the rest of the baseline transplant characteristics were comparable. There were no significant differences in the HbA1c, weight gain, rejection rate, and incidence of secondary diabetic macrovascular complications post-transplant between DBD and DCD recipients. The 1-, 5-, and 10-year patient and graft survival were similar in both the groups. PTA from DCD donors have equivalent metabolic outcomes and survival (patient/graft) as that of DBD donors.


Assuntos
Transplante de Pâncreas , Obtenção de Tecidos e Órgãos , Humanos , Doadores de Tecidos , Sobrevivência de Enxerto , Morte Encefálica , Sistema de Registros , Aumento de Peso , Reino Unido/epidemiologia , Estudos Retrospectivos , Morte
3.
Kidney Int ; 104(3): 526-541, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37172690

RESUMO

The Banff Classification for Allograft Pathology includes the use of gene expression in the diagnosis of antibody-mediated rejection (AMR) of kidney transplants, but a predictive set of genes for classifying biopsies with 'incomplete' phenotypes has not yet been studied. Here, we developed and assessed a gene score that, when applied to biopsies with features of AMR, would identify cases with a higher risk of allograft loss. To do this, RNA was extracted from a continuous retrospective cohort of 349 biopsies randomized 2:1 to include 220 biopsies in a discovery cohort and 129 biopsies in a validation cohort. The biopsies were divided into three groups: 31 that fulfilled the 2019 Banff Criteria for active AMR, 50 with histological features of AMR but not meeting the full criteria (Suspicious-AMR), and 269 with no features of active AMR (No-AMR). Gene expression analysis using the 770 gene Banff Human Organ Transplant NanoString panel was carried out with LASSO Regression performed to identify a parsimonious set of genes predictive of AMR. We identified a nine gene score that was highly predictive of active AMR (accuracy 0.92 in the validation cohort) and was strongly correlated with histological features of AMR. In biopsies suspicious for AMR, our gene score was strongly associated with risk of allograft loss and independently associated with allograft loss in multivariable analysis. Thus, we show that a gene expression signature in kidney allograft biopsy samples can help classify biopsies with incomplete AMR phenotypes into groups that correlate strongly with histological features and outcomes.


Assuntos
Transplante de Rim , Humanos , Anticorpos , Biópsia , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/genética , Rejeição de Enxerto/patologia , Transplante de Rim/efeitos adversos , Estudos Retrospectivos
4.
Transpl Int ; 35: 10490, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35781938

RESUMO

Ethnic disparities in the outcomes after simultaneous pancreas kidney (SPK) transplantation still exist. The influence of ethnicity on the outcomes of pancreas transplantation in the UK has not been reported and hence we aimed to investigate our cohort. A retrospective analysis of all pancreas transplant recipients (n = 171; Caucasians = 118/Black Asian Ethnic Minorities, BAME = 53) from 2006 to 2020 was done. The median follow-up was 80 months. Patient & pancreas graft survival, rejection rate, steroid free maintenance rate, HbA1c, weight gain, and the incidence of secondary diabetic complications post-transplant were compared between the groups. p < 0.003 was considered significant (corrected for multiple hypothesis testing). Immunosuppression consisted of alemtuzumab induction and steroid free maintenance with tacrolimus and mycophenolate mofetil. Pancreas graft & patient survival were equivalent in both the groups. BAME recipients had a higher prevalence of type-2 diabetes mellitus pre-transplant (BAME = 30.19% vs. Caucasians = 0.85%, p < 0.0001), and waited for a similar time to transplantation once waitlisted, although pre-emptive SPK transplantation rate was higher for Caucasian recipients (Caucasians = 78.5% vs. BAME = 0.85%, p < 0.0001). Despite equivalent rejections & steroid usage, BAME recipients gained more weight (BAME = 7.7% vs. Caucasians = 1.8%, p = 0.001), but had similar HbA1c (functioning grafts) at 3-,12-, 36-, and 60-months post-transplant.


Assuntos
Transplante de Rim , Transplante de Pâncreas , Etnicidade , Hemoglobinas Glicadas , Rejeição de Enxerto , Humanos , Imunossupressores/uso terapêutico , Estudos Retrospectivos , Esteroides , Reino Unido/epidemiologia
5.
Front Nephrol ; 2: 923813, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37675026

RESUMO

Background: Post-transplant glomerulonephritis (PTGN) has been associated with inferior long-term allograft survival, and its incidence varies widely in the literature. Methods: This is a cohort study of 7,623 patients transplanted between 2005 and 2016 at four major transplant UK centres. The diagnosis of glomerulonephritis (GN) in the allograft was extracted from histology reports aided by the use of text-mining software. The incidence of the four most common GN post-transplantation was calculated, and the risk factors for disease and allograft outcomes were analyzed. Results: In total, 214 patients (2.8%) presented with PTGN. IgA nephropathy (IgAN), focal segmental glomerulosclerosis (FSGS), membranous nephropathy (MN), and membranoproliferative/mesangiocapillary GN (MPGN/MCGN) were the four most common forms of post-transplant GN. Living donation, HLA DR match, mixed race, and other ethnic minority groups were associated with an increased risk of developing a PTGN. Patients with PTGN showed a similar allograft survival to those without in the first 8 years of post-transplantation, but the results suggest that they do less well after that timepoint. IgAN was associated with the best allograft survival and FSGS with the worst allograft survival. Conclusions: PTGN has an important impact on long-term allograft survival. Significant challenges can be encountered when attempting to analyze large-scale data involving unstructured or complex data points, and the use of computational analysis can assist.

6.
Nephrol Dial Transplant ; 37(8): 1576-1584, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34320215

RESUMO

BACKGROUND: The diagnosis of antibody-mediated rejection (AMR) is reached using the Banff Classification for Allograft Pathology, which now includes gene expression analysis. In this study, we investigate the application of 'increased expression of thoroughly validated gene transcripts/classifiers strongly associated with AMR' as diagnostic criteria. METHOD: We used quantitative real-time polymerase chain reaction for 10 genes associated with AMR in a retrospective cohort of 297 transplant biopsies, including biopsies that met the full diagnostic criteria for AMR, even without molecular data (AMR, n = 27), biopsies that showed features of AMR, but that would only meet criteria for AMR with increased transcripts [suspicious for AMR (AMRsusp), n = 49] and biopsies that would never meet criteria for AMR (No-AMR, n = 221). RESULTS: A 10-gene AMR score trained by a receiver-operating characteristic to identify AMR found 16 cases with a high score among the AMRsusp cases (AMRsusp-high) that had significantly worse graft survival than those with a low score (AMRsusp-low; n = 33). In both univariate and multivariate Cox regression analysis, the AMR 10-gene score was significantly associated with an increased hazard ratio (HR) for graft loss (GL) in the AMRsusp group (HR = 1.109, P = 0.004 and HR = 1.138, P = 0.012, respectively), but not in the whole cohort. Net reclassification index and integrated discrimination improvement analyses demonstrated improved risk classification and superior discrimination, respectively, for GL when considering the gene score in addition to histological and serological data, but only in the AMRsusp group, not the whole cohort. CONCLUSIONS: This study provides evidence that a gene score strongly associated with AMR helps identify cases at higher risk of GL in biopsies that are suspicious for AMR but do not meet full criteria.


Assuntos
Transplante de Rim , Anticorpos , Biópsia , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/genética , Sobrevivência de Enxerto , Humanos , Transplante de Rim/efeitos adversos , Estudos Retrospectivos
7.
Transpl Int ; 34(10): 1770-1775, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34288160

RESUMO

As SARS-CoV-2 vaccines have started to be rolled out, a key question facing transplant units has been whether listing for transplantation should be contingent on recipients having received a vaccine. We aimed to provide an ethical framework when considering potential transplant candidates who decline vaccination. We convened a working group comprising transplant professionals, lay members and patients and undertook a literature review and consensus process. This group's work was also informed by discussions in two hospital clinical ethics committees. We have reviewed arguments for and against mandating vaccination prior to listing for kidney transplantation and considered some practical difficulties which may be associated with a policy of mandated vaccination. Rather than requiring that all patients must receive the SARS-CoV-2 vaccine prior to transplant listing, we recommend considering vaccination status as one of a number of SARS-CoV-2-related risk factors in relation to transplant listing. Transplant units should engage in individualised risk-benefit discussions with patients, avoid the language of mandated treatments and strongly encourage uptake of the vaccine in all patient groups, using tailor-made educational initiatives.


Assuntos
COVID-19 , Transplante de Rim , Vacinas contra COVID-19 , Humanos , SARS-CoV-2 , Vacinação
8.
Kidney Int Rep ; 6(1): 46-55, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33173838

RESUMO

INTRODUCTION: There are limited data pertaining to comparative outcomes of remaining on dialysis versus kidney transplantation as the threat of coronavirus disease 2019 (COVID-19) remains. In this study we delineate the differential risks involved using serologic methods to help define exposure rates. METHODS: From a cohort of 1433 patients with end-stage kidney disease (ESKD), we analyzed COVID-19 infection rates and outcomes in 299 waitlist patients compared with 237 transplant recipients within their first year post-transplant. Patients were followed over a 68-day period from the time our transplant program closed due to COVID-19. RESULTS: The overall mortality rates in waitlist and transplant populations were equivalent (P = 0.69). However, COVID-19 infection was more commonly diagnosed in the waitlist patients (P = 0.001), who were more likely to be tested by reverse transcriptase polymerase chain reaction (P = 0.0004). Once infection was confirmed, mortality risk was higher in the transplant patients (P = 0.015). The seroprevalence in dialysis and transplant patients with undetected infection was 18.3% and 4.6%, respectively (P = 0.0001). After adjusting for potential screening bias, the relative risk of death after a diagnosis of COVID-19 remained higher in transplant recipients (hazard ratio = 3.36 [95% confidence interval = 1.19-9.50], P = 0.022). CONCLUSIONS: Although COVID-19 infection was more common in the waitlist patients, a higher COVID-19‒associated mortality rate was seen in the transplant recipients, resulting in comparable overall mortality rates.

10.
Clin Transplant ; 34(11): e14065, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32805760

RESUMO

Pancreas transplant longevity is limited by immune rejection, which is diagnosed by graft biopsy using the Banff Classification. The histological criteria for antibody-mediated rejection (AMR) are poorly reproducible and inconsistently associated with outcome. We hypothesized that a 34-gene set associated with antibody-mediated rejection in other solid organ transplants could improve diagnosis in pancreas grafts. The AMR 34-gene set, comprising endothelial, natural killer cell and inflammatory genes, was quantified using the NanoString platform in 52 formalin-fixed, paraffin-embedded pancreas transplant biopsies from 41 patients: 15 with pure AMR or mixed rejection, 22 with T cell-mediated rejection/borderline and 15 without rejection. The AMR 34-gene set was significantly increased in pure AMR and mixed rejection (P = .001) vs no rejection. The gene set predicted histological AMR with an area under the receiver operating characteristic curve (ROC AUC) of 0.714 (P = .004). The AMR 34-gene set was the only biopsy feature significantly predictive of allograft failure in univariate analysis (P = .048). Adding gene expression to DSA and histology increased ROC AUC for the prediction of failure from 0.736 to 0.770, but this difference did not meet statistical significance. In conclusion, assessment of transcripts has the potential to improve diagnosis and outcome prediction in pancreas graft biopsies.


Assuntos
Anticorpos , Rejeição de Enxerto , Aloenxertos , Biópsia , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/etiologia , Humanos , Isoanticorpos , Pâncreas
11.
J Am Soc Nephrol ; 31(8): 1815-1823, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32561681

RESUMO

BACKGROUND: During the coronavirus disease 2019 (COVID-19) epidemic, many countries have instituted population-wide measures for social distancing. The requirement of patients on dialysis for regular treatment in settings typically not conducive to social distancing may increase their vulnerability to COVID-19. METHODS: Over a 6-week period, we recorded new COVID-19 infections and outcomes for all adult patients receiving dialysis in a large dialysis center. Rapidly introduced control measures included a two-stage routine screening process at dialysis entry (temperature and symptom check, with possible cases segregated within the unit and tested for SARS-CoV-2), isolated dialysis in a separate unit for patients with infection, and universal precautions that included masks for dialysis nursing staff. RESULTS: Of 1530 patients (median age 66 years; 58.2% men) receiving dialysis, 300 (19.6%) developed COVID-19 infection, creating a large demand for isolated outpatient dialysis and inpatient beds. An analysis that included 1219 patients attending satellite dialysis clinics found that older age was a risk factor for infection. COVID-19 infection was substantially more likely to occur among patients on in-center dialysis compared with those dialyzing at home. We observed clustering in specific units and on specific shifts, with possible implications for aspects of service design, and high rates of nursing staff illness. A predictive epidemic model estimated a reproduction number of 2.2; cumulative cases deviated favorably from the model from the fourth week, suggesting that the implemented measures controlled transmission. CONCLUSIONS: The COVID-19 epidemic affected a large proportion of patients at this dialysis center, creating service pressures exacerbated by nursing staff illness. Details of the control strategy and characteristics of this epidemic may be useful for dialysis providers and other institutions providing patient care.


Assuntos
Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Controle de Infecções/métodos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Idoso , Betacoronavirus , COVID-19 , Registros Eletrônicos de Saúde , Feminino , Febre/complicações , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Pandemias , Isolamento de Pacientes , Modelos de Riscos Proporcionais , Quarentena , Diálise Renal/efeitos adversos , Fatores de Risco , SARS-CoV-2 , Serviços Urbanos de Saúde/organização & administração
12.
Front Immunol ; 11: 79, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117242

RESUMO

RituxiCAN-C4 combined an open-labeled randomized controlled trial (RCT) in 7 UK centers to assess whether rituximab could stabilize kidney function in patients with chronic rejection, with an exploratory analysis of how B cell-depletion influenced T cell anti-donor responses relative to outcome. Between January 2007 and March 2015, 59 recruits were enrolled after screening, 23 of whom consented to the embedded RCT. Recruitment was halted when in a pre-specified per protocol interim analysis, the RCT was discovered to be significantly underpowered. This report therefore focuses on the exploratory analysis, in which we confirmed that when B cells promoted CD4+ anti-donor IFNγ production assessed by ELISPOT, this associated with inferior clinical outcome; these patterns were inhibited by optimized immunosuppression but not rituximab. B cell suppression of IFNγ production, which associated with number of transitional B cells and correlated with slower declines in kidney function was abolished by rituximab, which depleted transitional B cells for prolonged periods. We conclude that in this patient population, optimized immunosuppression but not rituximab promotes anti-donor alloresponses associated with favorable outcomes. Clinical Trial Registration: Registered with EudraCT (2006-002330-38) and www.ClinicalTrials.gov, identifier: NCT00476164.


Assuntos
Rejeição de Enxerto/terapia , Sobrevivência de Enxerto/imunologia , Terapia de Imunossupressão , Imunossupressores/farmacologia , Transplante de Rim , Rituximab/farmacologia , Adulto , Linfócitos B/imunologia , Feminino , Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto/efeitos dos fármacos , Histocompatibilidade , Humanos , Isoanticorpos , Rim , Masculino , Pessoa de Meia-Idade , Doadores de Tecidos
13.
Aust J Rural Health ; 27(5): 433-437, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31512329

RESUMO

PROBLEM: Diabetes-related foot disease causes significant health system costs and is a leading cause of morbidity and disproportionately affects rural populations. Total contact casts or instant total contact casts are gold standard for management of foot ulcerations resulting from diabetes-related foot disease. The aim of this study was to evaluate the impact of a podiatrist-led casting service model within a rural and regional setting. DESIGN: The implementation of the service model was evaluated over a 12-month period using a quality improvement approach, informed by multiple methods. Quantitative and qualitative methods were used. SETTING: An outpatient high-risk foot clinic and community-based podiatry services within a large regional health service. The location was central Victoria, servicing rural communities within the Loddon Mallee region. KEY MEASURES FOR IMPROVEMENT: Patient-related data included information relating to demographics, diabetes and foot pathologies. Service-related data included occasions of service, locations and the number and type of casts applied. STRATEGIES FOR CHANGE: Upskilling podiatrists to provide the service in a safe, supportive and sustainable manner and ensuring the podiatrist-led casting service model was sufficiently adaptable for patients to access at the rural sites. EFFECTS OF CHANGE: Increased access to total contact casts and instant total contact casts, comparable wound healing times to other studies and the model was able to be sustained. LESSONS LEARNT: Podiatrist-led casting resulted in increased utilisation of total contact casts and instant total contact casts. The increased use of instant total contact casts in particular may help address the lack of uptake of this treatment for people with diabetes-related foot disease, thereby improving rural health outcomes.


Assuntos
Moldes Cirúrgicos , Competência Clínica , Pé Diabético/terapia , Podiatria/educação , Serviços de Saúde Rural/organização & administração , Feminino , Grupos Focais , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Melhoria de Qualidade , Vitória
14.
Clin Kidney J ; 12(4): 550-558, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31384448

RESUMO

BACKGROUND: Patients who require acute initiation of dialysis have higher mortality rates when compared with patients with planned starts. Our primary objective was to explore the reasons and risk factors for acute initiation of renal replacement therapy (RRT) among patients with end-stage kidney disease (ESKD). Our secondary objective was to determine the difference in glomerular filtration rate (GFR) change in the year preceding RRT between elective and acute dialysis starts. METHODS: We conducted a single-centre retrospective observational study. ESKD patients either started dialysis electively (planned starters) or acutely and were known to renal services for >90 (unplanned starters) or <90 days (urgent starters). RESULTS: In all, 825 consecutive patients initiated dialysis between January 2013 and December 2015. Of these, 410 (49.7%) patients had a planned start. A total of 415 (50.3%) patients had an acute start on dialysis: 244 (58.8%) unplanned and 171 (41.2%) urgent. The reasons for acute dialysis initiation included acute illness (58%) and unexplained decline to ESKD (33%). Cardiovascular disease [n = 30 (22%)] and sepsis [n = 65 (48%)] accounted for the majority of acute systemic illness. Age and premorbid cardiovascular disease were independent risk factors for acute systemic illness among unplanned starts, whereas autoimmune disease accounted for the majority of urgent starts. The rate of decline in GFR was greater in the month preceding RRT among acute dialysis starters compared with planned starters (P < 0.001). CONCLUSIONS: Cardiovascular disease and advancing age were independent risk factors for emergency dialysis initiation among patients known to renal services for >3 months. The rapid and often unpredictable loss of renal function in the context of acute systemic illness poses a challenge to averting emergency dialysis start.

15.
Kidney Int Rep ; 4(1): 148-158, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30596178

RESUMO

INTRODUCTION: Immunohistochemical staining for C4d in peritubular capillaries has been part of antibody-mediated rejection (AbMR) definition in the Banff Classification for Allograft Pathology since 2003. However, it has limited sensitivity and specificity, therefore the clinical significance of C4d-positive biopsies without evidence of rejection (C4d+ WER) is unknown. We investigated the transcript levels of genes associated with AbMR in C4d+ WER biopsies from both ABO-compatible and incompatible renal transplant patients. METHODS: RNA was extracted from formalin-fixed paraffin-embedded renal transplant biopsies (n = 125) and gene expression analysis of 35 AbMR-associated transcripts carried out using the NanoString nCounter system. RESULTS: AbMR-associated transcripts were significantly increased in samples with AbMR or suspicious AbMR. A subgroup of 17 of 35 transcripts that best distinguished AbMR from C4d-negative biopsies without evidence of rejection was used to study C4d+ WER samples. There was no differential expression between C4d-negative and C4d+ WER from both ABO-incompatible and -compatible transplants. The geometric mean of 17 differentially expressed genes was used to assign the C4d+ WER biopsies a high- or low-AbMR transcript score. Follow-up biopsies showed AbMR within 1 year of initial biopsy in 5 of 7 high-AbMR transcript patients but only 2 of 46 low-AbMR transcript patients. In multivariate logistic regression analysis, elevated transcript levels in a C4d+ WER biopsy were associated with increased odds for biopsy-proven AbMR on follow-up (P = 0.032, odds ratio 16.318), whereas factors including donor-specific antibody (DSA) status and time since transplantation were not. CONCLUSION: Gene expression analysis in C4d+ WER samples has the potential to identify patients at higher risk of developing AbMR.

16.
Am J Transplant ; 18(6): 1370-1379, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29392897

RESUMO

Improvements in immunosuppression have modified short-term survival of deceased-donor allografts, but not their rate of long-term failure. Mismatches between donor and recipient HLA play an important role in the acute and chronic allogeneic immune response against the graft. Perfect matching at clinically relevant HLA loci does not obviate the need for immunosuppression, suggesting that additional genetic variation plays a critical role in both short- and long-term graft outcomes. By combining patient data and samples from supranational cohorts across the United Kingdom and European Union, we performed the first large-scale genome-wide association study analyzing both donor and recipient DNA in 2094 complete renal transplant-pairs with replication in 5866 complete pairs. We studied deceased-donor grafts allocated on the basis of preferential HLA matching, which provided some control for HLA genetic effects. No strong donor or recipient genetic effects contributing to long- or short-term allograft survival were found outside the HLA region. We discuss the implications for future research and clinical application.


Assuntos
Estudo de Associação Genômica Ampla , Transplante de Rim , Doadores de Tecidos , Transplantados , Adulto , Replicação do DNA , Feminino , Genótipo , Sobrevivência de Enxerto/imunologia , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Transplante Homólogo
17.
Transplant Direct ; 3(8): e192, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28795143

RESUMO

BACKGROUND: Nonadherence to immunosuppressants is associated with rejection and allograft loss. Intrapatient variability (IPV) of immunosuppression levels is a marker of nonadherence. This study describes the impact of IPV of tacrolimus levels in patients receiving a tacrolimus monotherapy immunosuppression protocol. METHODS: We retrospectively analyzed the outpatient tacrolimus levels of kidney-only transplant patients taken between 6 and 12 months posttransplant. IPV was determined using the coefficient of variance. RESULTS: Six hundred twenty-eight patients with a mean number of 8.98 ± 3.81 tacrolimus levels and a mean follow-up of 4.72 ± 2.19 years were included. Multivariate analysis showed death was associated with increasing age (1.04 [1.01-1.07], P = 0.0055), diabetes at time of transplant (2.79 [1.44-5.41], P = 0.0024), and rejection (2.34 [1.06-5.19], P = 0.036). Variables associated with graft loss included the highest variability group (2.51 [1.01-6.27], P = 0.048), mean tacrolimus level less than 5 ng/mL (4.32 [1.94-9.63], P = 0.0003), a high clinic nonattendance rate (1.10 [1.01-1.20], P = 0.03), and rejection (9.83 [4.62-20.94], P < 0.0001). Independent risk factors for rejection were de novo donor-specific antibody (3.15 [1.84-5.39], P < 0.0001), mean tacrolimus level less than 5 ng/mL (2.57 [1.27-5.19], P = 0.00860, and a high clinic nonattendance rate (1.11 [1.05-1.18], P = 0.0005). CONCLUSIONS: This study shows that high tacrolimus IPV and clinic nonattendance are associated with inferior allograft survival. Interventions to minimize the causes of high variability, particularly nonadherence are essential to improve long-term allograft outcomes.

18.
Kidney Int ; 92(4): 942-952, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28673452

RESUMO

IgA nephropathy (IgAN) is a common cause of chronic kidney disease and end-stage renal failure, especially in young people. Due to a wide range of clinical outcomes and difficulty in predicting response to immunosuppression, we need to understand why and identify which patients with IgAN will develop progressive renal impairment. A deletion polymorphism affecting the genes encoding the complement factor H-related protein (FHR)-1 and FHR-3 is robustly associated with protection against IgAN. Some FHR proteins, including FHR-1 and FHR-5, antagonize the ability of complement factor H (fH), the major negative regulator of the complement alternative pathway, to inhibit complement activation on surfaces, a process termed fH deregulation. From a large cohort of patients, we demonstrated that plasma FHR-1 and the FHR-1/fH ratio were elevated in IgAN and associated with progressive disease. Plasma FHR-1 negatively correlated with eGFR but remained elevated in patients with IgAN with normal eGFR. Serum FHR5 was slightly elevated in IgAN but did not correlate with eGFR. Neither FHR5 levels nor the FHR-5/fH ratio was associated with progressive disease. However, higher serum FHR-5 levels were associated with a lack of response to immunosuppression, the presence of endocapillary hypercellularity, and histology scores of disease severity (the Oxford Classification MEST score). Thus, FHR-1 and FHR-5 have a role in IgAN disease progression.


Assuntos
Proteínas Inativadoras do Complemento C3b/análise , Via Alternativa do Complemento/imunologia , Proteínas do Sistema Complemento/análise , Glomerulonefrite por IGA/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Via Alternativa do Complemento/efeitos dos fármacos , Progressão da Doença , Feminino , Taxa de Filtração Glomerular , Glomerulonefrite por IGA/tratamento farmacológico , Glomerulonefrite por IGA/imunologia , Glomerulonefrite por IGA/patologia , Humanos , Imunossupressores/uso terapêutico , Rim/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Adulto Jovem
19.
Transpl Int ; 30(11): 1110-1118, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28493506

RESUMO

The optimal dose of alemtuzumab for renal transplant induction is not known, and the doses reported in the literature vary. This study compares two separate dosing regimens of alemtuzumab in renal transplantation. The first is a standard fixed dose of 30 mg (SD), and the second is a dose adjusted for body weight at 0.4 mg/kg (AD). In this first year post-transplant, there was no difference in patient [HR 0.64 (0.22-1.86), P = 0.39] or allograft survival [HR 1.18 (0.48-2.90), P = 0.72] between the two groups. There was also no difference in overall rejection-free survival [HR 1.12 (0.79-1.58), P = 0.53]. However, absolute lymphocyte count was significantly higher at all measured time points in the first year in the AD group. There were also less episodes of urosepsis [HR 1.38 (1.03-1.85), P = 0.037] and fungal infection [HR 5.15 (2.00-13.28), P = 0.015] in the AD group compared with the SD group. This study shows that AD alemtuzumab is associated with earlier lymphocyte repletion and less infective episodes in the first year postrenal transplant, without increasing the risk of rejection. This work highlights the need for studies into the optimal dosing of monoclonal antibodies used in transplantation.


Assuntos
Alemtuzumab/administração & dosagem , Antineoplásicos Imunológicos/administração & dosagem , Infecções/induzido quimicamente , Transplante de Rim , Linfócitos/efeitos dos fármacos , Alemtuzumab/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Peso Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
20.
World J Transplant ; 7(1): 34-42, 2017 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-28280693

RESUMO

AIM: To analyse the risk factors and outcomes of delayed graft function (DGF) in patients receiving a steroid sparing protocol. METHODS: Four hundred and twenty-seven recipients of deceased donor kidney transplants were studied of which 135 (31.6%) experienced DGF. All patients received monoclonal antibody induction with a tacrolimus based, steroid sparing immunosuppression protocol. RESULTS: Five year patient survival was 87.2% and 94.9% in the DGF and primary graft function (PGF) group respectively, P = 0.047. Allograft survival was 77.9% and 90.2% in the DGF and PGF group respectively, P < 0.001. Overall rejection free survival was no different between the DGF and PGF groups with a 1 and 5 year rejection free survival in the DGF group of 77.7% and 67.8% compared with 81.3% and 75.3% in the PGF group, P = 0.19. Patients with DGF who received IL2 receptor antibody induction were at significantly higher risk of rejection in the early post-transplant period than the group with DGF who received alemtuzumab induction. On multivariate analysis, risk factors for DGF were male recipients, recipients of black ethnicity, circulatory death donation, preformed DSA, increasing cold ischaemic time, older donor age and dialysis vintage. CONCLUSION: Alemtuzumab induction may be of benefit in preventing early rejection episodes associated with DGF. Prospective trials are required to determine optimal immunotherapy protocols for patients at high risk of DGF.

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