Efficacy and safety of single-dose anti-thymocyte globulin versus basiliximab induction therapy in pediatric kidney transplant recipients: A retrospective comparative cohort study.

BACKGROUND: This study aimed to compare the efficacy and safety of basiliximab (BAS) versus a single dose of anti-thymocyte globulin (r-ATG) induction therapy in pediatric kidney transplant recipients (KTRs). METHODS: This single-center retrospective comparative cohort study included all pediatric KTRs from May 2013 to April 2018 and followed up to 12 months. In the first period, all recipients received BAS, while from May 2016, a single 3 mg/kg dose of r-ATG was instituted. Maintenance therapy consisted of a calcineurin inhibitor plus prednisone plus azathioprine or mycophenolate. RESULTS: A total of 227 patients were included (BAS, n = 113; r-ATG, n = 114). The main combination of immunosuppressive drugs was tacrolimus, prednisone, and azathioprine in both groups (87% vs. 88%, p = .718). Patients receiving r-ATG showed superior survival-free of the composite endpoint (acute rejection, graft loss, or death; 76% vs. 61%, p = .003; HR 2.08, 1.29-3.34, p = .003) and lower incidence of biopsy-proven acute rejection (10% vs. 21%, p = .015). There was no difference in the overall incidence of CMV infection (33% vs. 37%, p = .457), PTLD (1% vs. 3%, p = .309), 30-day hospital readmissions (24% vs. 23%, p = .847), and kidney function at 12 months (86 ± 29 vs. 84 ± 30 mL/min/1.73m2, p = .614). CONCLUSIONS: These data suggest that induction therapy with a single 3 mg/kg dose of r-ATG is associated with higher efficacy for preventing acute rejection and similar safety profile compared to BAS.

Long-term Kidney Transplant Survival Across the Globe.

BACKGROUND: The outcomes after kidney transplantation (KT), including access, wait time, and other issues around the globe, have been studied. However, issues do vary from one country to another. METHODS: We obtained data from several countries from North America, South America, Europe, Asia, and Australia, including the number of patients awaiting KT from 2015, transplant rate per million population (pmp), proportion of living donor and deceased donor (LD/DD) KT, and posttransplant survival. We also sought opinions on key difficulties faced by each of these countries with respect to KT and long-term survival. RESULTS: Variation in access to KT across the globe was noted. Countries with the highest rates of KT pmp included the United States (79%) and Spain (71%). A higher proportion of LD transplants was noted in Japan (93%), India (85%), Singapore (63%), and South Korea (63%). A higher proportion of DD KTs was noted in Spain (90%), Brazil (90%), France (85%), Italy (85%), Finland (85%), Australia-New Zealand (80%), and the United States (77%). The 5-y graft survival for LD was highest in South Korea (95%), Singapore (94%), Italy (93%), Finland (93%), and Japan (93%), whereas for DD, it was South Korea (93%), Italy (88%), Japan (86%), and Singapore (86%). The common issues surrounding KTs are access and a limited number of LDs and DDs. Key issues identified for long-term survival were increasing age of donors and recipients, higher recipient comorbidity, and posttransplant events, such as alloimmune injury to the kidney, infection, cancer, and suboptimal adherence to therapy. CONCLUSIONS: A unified approach is necessary to improve issues surrounding KT as the demand continues to increase.

Patterns of Circulating Cytokines and Vascular Markers' Response in the Presence of COVID-19 in Kidney Transplant Recipients Compared with Non-Transplanted Patients.

COVID-19's severity has been associated with a possible imbalance in the cross-regulation of cytokines and vascular mediators. Since the beginning of the pandemic, kidney transplant recipients (KTRs) have been identified as patients of high vulnerability to more severe diseases. Thus, aiming to describe the patterns of cytokines and vascular mediators and to trace patients' differences according to their KTR status, this prospective study enrolled 67 COVID-19 patients (20 KTRs) and 29 non-COVID-19 controls before vaccination. A panel comprising 17 circulating cytokines and vascular mediators was run on samples collected at different time points. The cytokine and mediator patterns were investigated via principal component analysis (PCA) and correlation-based network (CBN). In both groups, compared to their respective controls, COVID-19 was associated with higher levels of cytokines and vascular mediators. Differentiating between the KTRs and non-KTRs, the number of correlations was much higher in the non-KTRs (44 vs. 14), and the node analysis showed the highest interactions of NGAL and sVCAM-1 in the non-KTRs and KTRs (9 vs. 4), respectively. In the PCA, while the non-KTRs with COVID-19 were differentiated from their controls in their IL-10, IFN-α, and TNF-α, this pattern was marked in the NGAL, sVCAM-1, and IL-8 of the KTRs.

Preemptive kidney transplantation: why, when, and how? / Transplante renal preemptivo: por que, quando e como?

ABSTRACT Among renal replacement therapies, preemptive kidney transplantation (PKT) presents the best clinical, social, and economic results. However, it is still infrequently chosen as first therapy for patients with irreversible kidney failure. Initiatives in different parts of the world were developed to identify the reasons why PKT is still not widely used and to facilitate the access of patients with end-stage kidney disease to the advantages associated with it. This article addresses the main advantages and difficulties of PKT and discusses when it should be indicated and how to prepare potential recipients for PKT.

Resumo Entre as terapias renais substitutivas, o transplante renal preemptivo (TRP) apresenta os melhores resultados clínicos, sociais e econômicos. No entanto, ainda é raramente escolhido como primeira terapia para pacientes com falência renal irreversível. Foram desenvolvidas iniciativas em diferentes partes do mundo para identificar as razões pelas quais o TRP ainda não é amplamente utilizado e para facilitar o acesso de pacientes com doença renal em estágio terminal às vantagens associadas ao mesmo. Este artigo aborda as principais vantagens e dificuldades do TRP e discute quando ele deve ser indicado e como preparar potenciais receptores para o TRP.

The Association Between Kidney Donor Profile Index and 1-y Graft Function.

The association between Kidney Donor Profile Index (KDPI) and 1-y estimated glomerular filtration rate (eGFR) with long-term kidney graft survival is well known. Yet, the association between KDPI and 1-y eGFR remains uncertain considering the several concurrent competing risk factors. Methods: This single-center, retrospective cohort study analyzed data from 3059 consecutive deceased donor kidney transplant recipients with a 1-y follow-up from January 2013 to December 2017. The aim was to determine the association between the KDPI strata (0%-35%, 36%-50%, 51%-85%, 86%-100%) and 1-y eGFR estimated by the CKD-EPI equation. Results: The incidence of delayed graft function (50.6% versus 59.3% versus 62.7% versus 62.0%; P < 0.001) and cytomegalovirus infection (36.7% versus 36.6% versus 43.3% versus 57.8%; P < 0.001) increased with increasing KDPI strata but not biopsy-proven acute rejection (9.1% versus 9.8% versus 8.4% versus 9.1%; P = 0.736). The median 1-y eGFR decreased with increasing KDPI strata (64.8 versus 53.5 versus 46.9 versus 39.1 mL/min/1.73 m2; P < 0.001). In the Cox regression, the higher the KDPI was, the lower the probability of a lower 1-y eGFR was. Assuming the 0%-35% strata as the reference, the likelihood of eGFR <50 mL/min/1.73 m2 was increased by 76.6% (hazard ratio [HR] = 1.767, 95% confidence interval [CI] = 1.406-2.220), 2.24- and 2.87-fold higher for KDPI higher >35%-50% (HR = 2.239, 95% CI = 1.862-2.691), and >51%-85% (HR = 2.871, 95% CI = 2.361-3.491), respectively. Other variables associated with a lower graft function were donor sex (HR male versus female = 0.896, 95% CI = 0.813-0.989) and cold ischemia time (HR for each hour = 1.011, 95% CI = 1.004-1.019). This association was sustained after the Poisson mediation analysis, including delayed graft function, cytomegalovirus, and acute rejection as mediators. Conclusions: In this cohort of deceased donor kidney recipients, KDPI, and cold ischemia time were the major independent risk factors associated with lower 1-y kidney function.

Challenges of Multidrug-resistant New Delhi Metallo-beta-Lactamase (NDM-1)-producing Enterobacteriaceae in Kidney Transplant Patients / Desafios da Enterobacteriaceae produtora de New Delhi Metalo-beta-Lactamase (NDM-1) multirresistente em pacientes com transplante renal

Abstract Background: The emergence of multidrug-resistant NDM-1-producing enterobacteriaceae strains has become a threat to inpatients, especially to immunosuppressed ones, such as kidney transplant recipients. NDM-1 is a carbapenemase that makes gram-negative bacteria resistant to many types of antibiotics. The incidence of carbapenemase-producing enterobacteria infection in solid organ transplant recipients is around 3 to 10%, with a mortality rate of up to 30%. Methods: We present a case series of 4 patients with NDM-1-producing enterobacteria isolated in urine cultures or rectal swabs. We also conducted a cross-sectional study 30 days after patient identification, collecting surveillance cultures (rectal swab) from all inpatients to assess the extent of spread of this resistance mechanism; a total of 101 patients were included. Results: Two patients were adequately treated with negative control cultures. The other two patients were not treated because they were asymptomatic and had subsequent negative urine cultures. No new colonization was identified in the cross-sectional screening, and no new cases of urinary NDM-1 infection were recorded after a 4-year follow-up. Conclusion: Surveillance for infections caused by multidrug-resistant strains in hospitals treating immunosuppressed patients should be continued and prompt action should be taken in cases of outbreaks of multidrug-resistant infections.

Resumo Histórico: O surgimento de cepas multirresistentes de enterobacteriaceae produtoras de NDM-1 tornou-se uma ameaça para pacientes hospitalizados, especialmente para os imunossuprimidos, como os receptores de transplante renal. NDM-1 é uma carbapenemase que torna as bactérias gram-negativas resistentes a muitos tipos de antibióticos. A incidência de infecção por enterobactérias produtoras de carbapenemas em receptores de transplante de órgãos sólidos é de cerca de 3 a 10%, com uma taxa de mortalidade de até 30%. Métodos: Apresentamos uma série de casos de 4 pacientes com enterobactérias produtoras de NDM-1 isoladas em culturas de urina ou esfregaços retais. Também realizamos um estudo transversal 30 dias após a identificação do paciente, coletando culturas de vigilância (esfregaço retal) de todos os pacientes internados para avaliar a extensão de disseminação deste mecanismo de resistência; foram incluídos um total de 101 pacientes. Resultados: Dois pacientes foram tratados adequadamente com culturas de controle negativo. Os outros dois pacientes não foram tratados porque eram assintomáticos e tiveram culturas de urina negativas subsequentes. Não foi identificada nenhuma nova colonização na triagem transversal, e não foram registrados novos casos de infecção urinária por NDM-1 após um acompanhamento de 4 anos. Conclusão: A vigilância de infecções causadas por cepas multirresistentes em hospitais que tratam pacientes imunossuprimidos deve ser continuada e devem ser tomadas medidas imediatas em casos de surtos desses tipos de infecções.

Migratory pattern of the coronavirus disease 2019 and high fatality rates among kidney transplant recipients: report from the Brazilian Multicenter Cohort Study / Padrão migratório da doença coronavírus 2019 e altas taxas de mortalidade entre receptores de transplante renal: relatório do Estudo de Coorte Multicêntrico Brasileiro

Abstract Introduction: The unprecedented coronavirus disease 2019 (COVID-19) pandemic has affected kidney transplant (KT) recipients, with worldwide fatality rates around 25%. Considering the well-known Brazilian socio-demographic disparities, this report describes for the first time the main outcomes of COVID-19 in KT recipients according to Brazilian geographic regions. Methods: This multicenter national retrospective analysis included data from KT recipients with confirmed COVID-19 between March and November 2020. Results: Thirty-five of the 81 centers (57% of KT activity in Brazil) reported 1,680 patients with COVID-19. The Northeast was the first to reach the peak in the number of infections. The Southeast, due to its population density, contributed with the largest number of patients. Patients had a median age of 52 years, 76% had hypertension and 34% diabetes, 75% were recipients of a deceased donor, and the time interval between diagnosis and transplantation was 5.9 years. In 53% of patients, immunosuppression was adjusted, and clinical support varied according to geographic region. Hospitalization was required for 65% of the patients, 35% of them needed intensive care, 25% mechanical ventilation, and 23% renal replacement therapy. The 90-day overall fatality was 21%, being 23% in the Southeast, 16% in the Northeast, and 19% in the Central-west and South regions. Conclusion: The migratory pattern of the pandemic among KT recipients followed that of the general population and the outcomes were influenced by regional features. COVID-19 in KT recipients was associated with high utilization of health-care resources and higher fatality rates than those reported in the general population.

Resumo Introdução: A pandemia da COVID-19 afetou receptores de transplante renal (TR), com taxas de mortalidade mundial em torno de 25%. Considerando as notórias disparidades sócio-demográficas brasileiras, este relatório descreve pela primeira vez principais características e desfechos da doença em receptores de TR, segundo as regiões geográficas. Métodos: Esta análise retrospectiva multicêntrica nacional incluiu dados de receptores de TR com COVID-19 confirmada entre Março/Novembro de 2020. Resultados: Trinta e cinco dos 81 centros (57% da atividade de transplante renal brasileira) relataram 1.680 pacientes com COVID-19. O Nordeste foi o primeiro a atingir o pico no número de infecções. O Sudeste, por sua densidade populacional, contribuiu com maior número de pacientes. Pacientes tinham em média 52 anos, 76% apresentavam hipertensão e 34% diabetes, 75% receptores de doador falecido e o tempo entre diagnóstico e transplante foi de 5,9 anos. Em 53% dos pacientes, os imunossupressores foram ajustados, e o tratamento variou segundo a região. Hospitalização foi necessária para 65% dos pacientes, 35% necessitaram de cuidados intensivos, 25% ventilação mecânica, e 23% terapia renal substitutiva. A mortalidade geral em 90 dias foi 21%, sendo 23% no Sudeste, 16% no Nordeste, e 19% nas regiões Centro-Oeste e Sul. Conclusão: O padrão migratório da pandemia entre os receptores de TR seguiu o da população em geral e os desfechos foram influenciados por características regionais. A COVID-19 em receptores de TR foi associada à alta utilização de recursos de saúde e taxas de mortalidade mais altas do que as relatadas na população em geral.

Predictive ability of severity scores and outcomes for mortality in kidney transplant recipients with coronavirus disease 2019 admitted to the intensive care unit: results from a Brazilian single-center cohort study / Capacidade preditiva de escores de gravidade e desfechos para mortalidade em receptores de transplante renal com COVID-2019 admitidos em unidade de terapia intensiva: resultados de um estudo de coorte brasileiro de um único centro

Abstract Background: the predictive ability of severity scores for mortality in patients admitted to intensive care units is not well-known among kidney transplanted (KT) patients, especially those diagnosed with coronavirus disease 2019 (COVID-19). The purpose of the present study was to evaluate the predictive ability of severity scores for mortality in KT recipients. Methods: 51 KT recipients with COVID-19 diagnosis were enrolled. The performance of the SOFA, SAPS 3, and APACHE IV tools in predicting mortality after COVID-19 was compared by the area under the ROC curve (AUC-ROC) and univariate Cox regression analysis was performed. Results: The 90-day cumulative incidence of death was 63.4%. Only APACHE IV score differed between survivors and nonsurvivors: 91.2±18.3 vs. 106.5±26.3, P = 0.03. The AUC- ROC of APACHE IV for predicting death was 0.706 (P = 0.04) and 0.656 (P = 0.06) at 7 and 90 days, respectively. Receiving a kidney from a deceased donor (HR = 3.16; P = 0.03), troponin levels at admission (HR for each ng/mL = 1.001; P = 0.03), APACHE IV score (HR for each 1 point = 1.02; P = 0.01), mechanical ventilation (MV) requirement (HR = 3.04; P = 0.002) and vasopressor use on the first day after ICU admission (HR = 3.85; P < 0.001) were associated with the 90-day mortality in the univariate analysis. Conclusion: KT recipients had high mortality, which was associated with type of donor, troponin levels, early use of vasopressors, and MV requirement. The other traditional severity scores investigated could not predict mortality.

RESUMO Introdução: a capacidade preditiva dos escores de gravidade para mortalidade em pacientes admitidos em unidades de terapia intensiva não é bem conhecida entre pacientes transplantados renais (TR), especialmente aqueles diagnosticados com doença coronavírus 2019 (COVID-19). Este estudo avaliou a capacidade preditiva dos escores de gravidade para mortalidade em receptores de TR. Métodos: Foram inscritos 51 receptores de TR diagnosticados com COVID-19. O desempenho das ferramentas SOFA, SAPS 3, APACHE IV em predizer mortalidade após COVID-19 foi comparado pela área sob a curva ROC (AUC-ROC) e realizou-se análise de regressão univariada de Cox. Resultados: A incidência cumulativa de óbito em 90 dias foi 63,4%. Somente APACHE IV diferiu entre sobreviventes e não-sobreviventes: 91,2±18,3 vs. 106,5±26,3; P = 0,03. A AUC-ROC do APACHE IV para predizer óbito foi 0,706 (P = 0,04) e 0,656 (P = 0,06) aos 7 e 90 dias, respectivamente. Receber rim de doador falecido (HR = 3,16; P = 0,03), níveis de troponina na admissão (HR para cada ng/mL = 1,001; P = 0,03), escore APACHE IV (HR para cada 1 ponto = 1,02; P = 0,01), necessidade de ventilação mecânica (VM) (HR = 3,04; P = 0,002), uso de vasopressor no primeiro dia após admissão na UTI (HR = 3,85; P < 0,001) foram associados à mortalidade em 90 dias na análise univariada. Conclusão: Receptores de TR apresentaram alta mortalidade, associada ao tipo de doador, níveis de troponina, uso precoce de vasopressores e necessidade de VM. Os outros escores tradicionais de gravidade investigados não puderam predizer mortalidade.

Paired kidney donation: are we going beyond reasonable limits in living-donor transplantation? / Doação renal pareada: estamos passando dos limites razoáveis no transplante entre vivos?

Abstract The growing demand for transplant kidneys requires strategies to increase organ supply and avoid long waiting periods on the list. The increase in the number of transplants from living donors involves the growth in the use of unrelated donors and paired kidney donation. Most of these transplants are performed in the USA, where they already represent, respectively, 34% and 16% of total transplants from living donors. In Latin America, and especially in Brazil, there is no collective enthusiasm for these modalities, either at the request of transplanters or that of the community, with the region's priority being to increase transplants from deceased donors, which growth can be up to three-fold. Concerning transplants from matched donors, the possible conflicting results between donors can generate public challenges and they risk compromise the concepts of equal opportunities for transplant candidates, with the possibility of generating resistance to organ donation, especially in regions with socioeconomic limitations and disparities in access to qualified health care and education. This donation model involves challenging ethical and logistical issues, which are subject to questionings, starting with an act of exchange between two pairs until reaching embarrassing proposals, which can compromise the altruistic character of organ donation, and thus not be universally incorporated.

Resumo A demanda crescente por rins para transplante requer estratégias para aumentar a oferta de órgãos e evitar longos períodos de espera em lista. O aumento no número de transplantes com doador vivo envolve o crescimento da utilização de doadores não aparentados e a doação renal pareada. A maior parte desses transplantes são realizados nos EUA, onde já representam, respectivamente, 34% e 16% do total de transplantes com doador vivo. Na América Latina, e especialmente no Brasil, não existe entusiasmo coletivo por essas modalidades, quer por demanda dos transplantadores ou da comunidade, sendo prioridade da região incrementar o transplante com doador falecido, cujo crescimento pode ser de até três vezes. Na modalidade de transplantes com doadores pareados, os possíveis resultados conflitantes entre doadores podem gerar questionamentos públicos e riscos que comprometem os conceitos de equidade de oportunidades para os candidatos a transplante, com possibilidade de gerar resistência à doação de órgãos, especialmente em regiões com limitações socioeconômicas e disparidades de acesso aos atendimentos de saúde e educação qualificados. Esse modelo de doação envolve questões éticas e logísticas desafiadoras, que estão sujeitas a questionamentos, começando por um ato de troca entre dois pares até alcançar propostas constrangedoras, o que pode comprometer o caráter altruístico da doação de órgãos, e assim não ser universalmente incorporado.

Transition from antigenemia to quantitative nucleic acid amplification testing in cytomegalovirus-seropositive kidney transplant recipients receiving preemptive therapy for cytomegalovirus infection.

Due to the high costs, the strategy to reduce the impact of cytomegalovirus (CMV) after kidney transplant (KT) involves preemptive treatment in low and middle-income countries. Thus, this retrospective cohort study compared the performance of antigenemia transitioned to quantitative nucleic acid amplification testing, RT-PCR, in CMV-seropositive KT recipients receiving preemptive treatment as a strategy to prevent CMV infection. Between 2016 and 2018, 363 patients were enrolled and received preemptive treatment based on antigenemia (n = 177) or RT-PCR (n = 186). The primary outcome was CMV disease. Secondarily, the CMV-related events were composed of CMV-infection and disease, which occurred first. There were no differences in 1-year cumulative incidence of CMV-disease (23.7% vs. 19.1%, p = 0.41), CMV-related events (50.8% vs. 44.1%, p = 0.20), neither in time to diagnosis (47.0 vs. 47.0 days) among patients conducted by antigenemia vs. RT-PCR, respectively. The length of CMV first treatment was longer with RT-PCR (20.0 vs. 27.5 days, p < 0.001), while the rate of retreatment was not different (14.7% vs. 11.8%, p = 0.48). In the Cox regression, acute rejection within 30 days was associated with an increased the risk (HR = 2.34; 95% CI = 1.12-4.89; p = 0.024), while each increase of 1 mL/min/1.73 m2 of 30-day eGFR was associated with a 2% reduction risk of CMV-disease (HR = 0.98; 95% CI = 0.97-0.99; p = 0.001). In conclusion, acute rejection and glomerular filtration rate are risk factors for CMV disease, showing comparable performance in the impact of CMV-related events between antigenemia and RT-PCR for preemptive treatment.

Temporal Reduction in COVID-19-Associated Fatality Among Kidney Transplant Recipients: The Brazilian COVID-19 Registry Cohort Study.

Data from the general population suggest that fatality rates declined during the course of the pandemic. This analysis, using data extracted from the Brazilian Kidney Transplant COVID-19 Registry, seeks to determine fatality rates over time since the index case on March 3rd, 2020. Data from hospitalized patients with RT-PCR positive SARS-CoV-2 infection from March to August 2020 (35 sites, 878 patients) were compared using trend tests according to quartiles (Q1: <72 days; Q2: 72-104 days; Q3: 105-140 days; Q4: >140 days after the index case). The 28-day fatality decreased from 29.5% (Q1) to 18.8% (Q4) (pfor-trend = 0.004). In multivariable analysis, patients diagnosed in Q4 showed a 35% reduced risk of death. The trend of reducing fatality was associated with a lower number of comorbidities (20.7-10.6%, p for-trend = 0.002), younger age (55-53 years, pfor-trend = 0.062), and better baseline renal function (43.6-47.7 ml/min/1.73 m2, pfor-trend = 0.060), and were confirmed by multivariable analysis. The proportion of patients presenting dyspnea (pfor-trend = 0.001) and hypoxemia (pfor-trend < 0.001) at diagnosis, and requiring intensive care was also found reduced (pfor-trend = 0.038). Despite possible confounding variables and time-dependent sampling differences, we conclude that COVID-19-associated fatality decreased over time. Differences in demographics, clinical presentation, and treatment options might be involved.

Long-Term Outcomes among Kidney Transplant Recipients and after Graft Failure: A Single-Center Cohort Study in Brazil.

BACKGROUND: The results of kidney transplantation are impacted by the categories of events responsible for patient death and graft failure. The objective of this study was to evaluate the causes of death and graft failure and outcomes after graft failure among kidney transplant recipients. METHODOLOGY: A retrospective cohort study was conducted with 944 patients who underwent kidney transplantation. Outcomes were categorized in a managed and hierarchical manner. RESULTS: The crude mortality rate was 10.8% (n=102): in 35.3% cause of death was infection, in 30.4% cardiovascular disease, and in 15.7% neoplasia and in 6.8%, it was not possible to determine the cause of death. The rate of graft loss was 10.6%. The main causes of graft failure were chronic rejection (40%), acute rejection (18.3%), thrombosis (17.3%), and recurrence of primary disease (16.5%). Failures due to an acute rejection occurred earlier than those due to chronic rejection and recurrence (p<0.0001). As late causes of graft loss, death with the functioning kidney occurred earlier than recurrence and chronic rejection (p=0.008). The outcomes after graft failure were retransplantation in 26.1% and death in 21.4%, at a mean of 25.5 and 21.4 months, respectively. CONCLUSION: It was possible to identify more than 90% of the events responsible for the deaths of transplanted patients, predominantly infectious and cardiovascular diseases. Among the causes of graft failure, chronic and acute rejections and recurrence were the main causes of graft failure which were followed more frequently by retransplantation than by death on dialysis.

Bortezomib in Kidney Transplant: Current Use and Perspectives.

BACKGROUND: Despite major advances in transplant medicine, antibody-mediated rejection (AMR) continues to have severe clinical implications and adversely affect graft survival. Therefore, the search for alternative drugs to treat AMR is widely pursued. The first-in-class proteasome inhibitor bortezomib (BZ) is a selective inhibitor of the 26S proteasome, which was initially approved for the treatment of malignant plasma cell disorders. METHODS: This review encompasses how our understanding of inhibiting proteasome pathway created the basis of BZ research and important milestones accomplished in AMR treatment in the transplant setting. It further discusses at length the results of clinical studies, the tolerability profile, drug-drug interactions and the perspectives of BZ use in desensitization protocols. RESULTS: Proteasome inhibition can downregulate NF-κB activity; decrease cell proliferation/differentiation; induce apoptosis via cell cycle arrest, endoplasmic reticulum stress and caspase induction due the accumulation of unfolded or misfolded proteins; and downregulate antigen presentation, cell-cell interaction, and cell migration. Proteasome inhibition is more evident in cells with high rate of protein synthesis and secretion, like plasma cells. These cells play a critical role in the production of antibodies during AMR. CONCLUSIONS: There is accumulating evidence that the proteasome inhibitor BZ may substantially affect the function and integrity of alloantibody-secreting plasma cells in AMR after organ solid transplant, as well as the activation, proliferation and differentiation of T- and B-lymphocytes. Recent clinical studies have provided evidence that BZ has the capability to downregulate circulating antibodies and treat AMR episodes. Additional randomized-controlled studies are required to assess the impact of BZ during short and long follow-ups.

Presence of arteriolar hyalinosis in post-reperfusion biopsies represents an additional risk to ischaemic injury in renal transplant.

AIM: The role of post-reperfusion biopsy findings as a predictor of early and long-term graft function and survival is still a target of research. METHODS: We analyzed data from 136 post-reperfusion biopsies performed in deceased donor renal transplanted patients from November 2008 to May 2012. We analyzed the presence of acute tubular necrosis (ATN), arteriolar hyalinosis (AH), intimal thickness (IT), interstitial fibrosis (IF) and glomerulosclerosis (GS). We also analyzed the impact of donor features on the following outcomes: delayed graft function (DGF) and chronic allograft dysfunction defined as eGFR < 60 mL/min at 1 year. RESULTS: The mean donor age was 41 years, 26% of whom were extended criteria donors (ECD), 33% had hypertension and 50% had cerebral vascular accident (CVA) as the cause of death. ATN was present in 87% of these biopsies, AH in 31%, IF in 21%, IT in 27% and GS in 32%. DGF occurred in 80% and chronic allograft dysfunction was present in 53%. AH was the only histological finding associated with DGF and chronic allograft dysfunction at 1 year. Patients with AH had a lower eGFR at 1 year than patients without it (49.8 mL/min × 64.5 mL/min, P = 0.02). In the multivariate analysis, risk variables for development of chronic graft dysfunction were male sex (odds ratio [OR] = 3.159 [CI: 1.22-8.16]; P = 0.018), acute rejection (OR = 8.91 [CI: 2.21-35.92]; P = 0.002), donor hypertension (OR = 2.94 [CI: 1.10-7.84]; P = 0.031), AH (OR = 3.96 [CI: 1.46-10.70]; P = 0.007) and eGFR at discharge (OR = 0.96 [CI: 0.93-0.98]; P = 0.005). In multivariate analysis, risk factors for AH were donor age ≥ 50 years (OR = 2.46 [CI: 1.10-5.44]; P = 0.027) and CVA as the cause of donor death (OR = 2.33 [CI: 1.05-5.15]; P = 0.007). CONCLUSION: The presence of AH in post-reperfusion biopsies is a marker of ageing and vascular disease and was associated with DGF and a one year poorer renal function. AH in donor biopsies superimposed to long ischaemic time is a predictor of renal function. The management of immunosuppression based on the presence of AH in post-reperfusion biopsy could be useful to improve long term graft function.

Expanding the pool of kidney donors: use of kidneys with acute renal dysfunction / Ampliando o pool de doadores de rim: utilização de órgãos com disfunção renal aguda

ABSTRACT Given the shortage of organs transplantation, some strategies have been adopted by the transplant community to increase the supply of organs. One strategy is the use of expanded criteria for donors, that is, donors aged >60 years or 50 and 59 years, and meeting two or more of the following criteria: history of hypertension, terminal serum creatinine >1.5mg/dL, and stroke as the donor´s cause of death. In this review, emphasis was placed on the use of donors with acute renal failure, a condition considered by many as a contraindication for organ acceptance and therefore one of the main causes for kidney discard. Since these are well-selected donors and with no chronic diseases, such as hypertension, renal disease, or diabetes, many studies showed that the use of donors with acute renal failure should be encouraged, because, in general, acute renal dysfunction is reversible. Although most studies demonstrated these grafts have more delayed function, the results of graft and patient survival after transplant are very similar to those with the use of standard donors. Clinical and morphological findings of donors, the use of machine perfusion, and analysis of its parameters, especially intrarenal resistance, are important tools to support decision-making when considering the supply of organs with renal dysfunction.

RESUMO Diante da escassez de órgãos para transplante, algumas estratégias têm sido adotadas pela comunidade transplantadora, no sentido de ampliar a oferta de órgãos. Uma delas é a utilização de rins de doadores com critérios expandidos, ou seja, doadores com idade >60 anos ou entre 50 e 59 anos, e que atendem a dois ou mais dos seguintes critérios: história de hipertensão, creatinina sérica terminal >1,5mg/dL e acidente vascular cerebral como causa de morte do doador. Nesta revisão, foi dada ênfase à utilização de doadores com disfunção renal aguda, condição considerada por muitos uma contraindicação para a aceitação de órgãos e, portanto, uma das principais causas de descarte de órgãos. Desde que sejam doadores bem selecionados e que não tenham doença renal crônica, como hipertensão ou diabetes, muitos trabalhos mostraram que o uso de doadores com disfunção renal aguda deve ser encorajado, pois, em geral, a disfunção renal aguda é de caráter reversível. Embora, a maioria dos estudos tenha demonstrado que há uma maior taxa de função retardada do enxerto com a utilização desses órgãos, os resultados de sobrevida do enxerto e do paciente após o transplante são muito semelhantes aos resultados obtidos da utilização de doadores padrão. Os achados clínicos e morfológicos do doador, a utilização da máquina de perfusão e a análise de seus parâmetros, principalmente a resistência intrarrenal, são importantes ferramentas de apoio para tomada de decisão no momento da oferta de órgãos com disfunção renal.

Ischemia and reperfusion injury in renal transplantation: hemodynamic and immunological paradigms / Lesão de isquemia e reperfusão no transplante renal: paradigmas hemodinâmico e imunológico

Ischemia and reperfusion injury is an inevitable event in renal transplantation. The most important consequences are delayed graft function, longer length of stay, higher hospital costs, high risk of acute rejection, and negative impact of long-term follow-up. Currently, many factors are involved in their pathophysiology and could be classified into two different paradigms for education purposes: hemodynamic and immune. The hemodynamic paradigm is described as the reduction of oxygen delivery due to blood flow interruption, involving many hormone systems, and oxygen-free radicals produced after reperfusion. The immune paradigm has been recently described and involves immune system cells, especially T cells, with a central role in this injury. According to these concepts, new strategies to prevent ischemia and reperfusion injury have been studied, particularly the more physiological forms of storing the kidney, such as the pump machine and the use of antilymphocyte antibody therapy before reperfusion. Pump machine perfusion reduces delayed graft function prevalence and length of stay at hospital, and increases long-term graft survival. The use of antilymphocyte antibody therapy before reperfusion, such as Thymoglobulin™, can reduce the prevalence of delayed graft function and chronic graft dysfunction.

A lesão de isquemia e reperfusão é um evento inevitável no transplante de rim, tendo como consequências retardo na função do enxerto, aumento no tempo de hospitalização e dos custos, aumento no risco de rejeição aguda e potencial impacto negativo na evolução a longo prazo. Atualmente, vários fatores estão implicados na fisiopatologia da lesão de isquemia e reperfusão, podendo ser didaticamente divididos em dois paradigmas: hemodinâmico e imunológico. O paradigma hemodinâmico é classicamente descrito como a privação de oxigênio pela interrupção do fluxo sanguíneo, envolvendo diversos sistemas hormonais e pela produção de radicais livres de oxigênio após a reperfusão. O paradigma imunológico tem sido descrito mais recentemente e envolve as células do sistema imune, sobretudo as células T, como papel fundamental na lesão. De acordo com esses conceitos, novas estratégias de prevenção dos impactos da lesão de isquemia e reperfusão têm sido estudadas, especialmente formas mais fisiológicas de preservação do órgão, como a preservação em máquina de perfusão e o uso de anticorpos depletores de linfócitos antes da reperfusão. A perfusão em máquina reduz a prevalência de retardo na função do enxerto e o tempo de hospitalização, além de melhorar a sobrevida do enxerto a longo prazo. Já o uso de anticorpos depletores de linfócitos, como Timoglobulina®, antes da reperfusão, pode diminuir a prevalência de retardo na função do enxerto e a disfunção crônica do mesmo.

Cytomegalovirus infection in renal transplantation: clinical aspects, management and the perspectives / Infecção pelo citomegalovírus no transplante de rim: aspectos clínicos, manejo e perspectivas

Cytomegalovirus infection is one of most frequent infectious complications after renal transplantation, and can be classified as primo-infection, when the transmission occurs through the graft, or reactivation, when the recipient is cytomegalovirus seropositive. After transplantation, cytomegalovirus can appear as an infection, when the patient presents with evidence of viral replication without symptoms or disease, which has two clinical spectra: typical viral syndrome or invasive disease, which is a less common form. Their effects can be classified as direct, while the disease is developed, or indirect, with an increase of acute rejection and chronic allograft dysfunction risks. Diagnosis must be made based on viremia by one of the standardized methods: antigenemia or PCR, which is more sensitive. The risk factors related to infection after transplantation are the serologic matching (positive donor and negative recipient) and anti-lymphocyte antibody drugs. One of the strategies to reduce risk of disease should be chosen for patients at high risk: preemptive treatment or universal prophylaxis. Recent clinical research has described ganciclovir resistance as an emergent problem in management of cytomegalovirus infection. Two types of mutation that cause resistance were described: UL97 (most frequent) and UL54. Today, sophisticated methods of immunologic monitoring to detect specific T-cell clones against cytomegalovirus are used in clinical practice to improve the management of high-risk patients after renal transplantation.

A infecção pelo citomegalovírus é uma das principais complicações após o transplante de rim, podendo ser classificada em primoinfecção, quando a transmissão ocorre por meio do enxerto, ou em reativação, quando o receptor é soropositivo. Do ponto de vista clínico, pode se apresentar como infecção, na ausência de sintomas, ou como doença, com dois diferentes espectros: a síndrome viral típica ou, menos comumente, a doença invasiva. Os efeitos podem ser diretos, que é o desenvolvimento da doença, ou indiretos, como aumento no risco de rejeição aguda e de disfunção crônica do enxerto. O diagnóstico deve ser feito por pesquisa de viremia por meio de um dos dois métodos padronizados: antigenemia ou PCR − sendo essa última a mais sensível. Os fatores de risco relacionados com a infecção após o transplante são o match sorológico (doador positivo e receptor negativo) e o uso de anticorpos antilinfócitos. Uma das estratégias de redução de risco de doença deve ser escolhida após o transplante nos pacientes de alto risco: tratamento preemptivo ou profilaxia. Recentemente, linhas de pesquisa clínica têm apontado a resistência ao ganciclovir como um problema emergente no manejo da infecção pelo citomegalovírus. Duas formas de mutação que causam resistência são descritas: UL97, que é a mais frequente, e a UL54. Atualmente, sofisticados métodos de monitorização imunológica, como a detecção de clones específicos de células T contra o citomegalovírus podem ser utilizados na prática clínica para o melhor manejo após o transplante renal dos pacientes de alto risco.

Podocyte Wnt/ß-catenin pathway is activated by integrin-linked kinase in clinical and experimental focal segmental glomerulosclerosis.

BACKGROUND: Changes in podocyte phenotype and function are characteristic of proteinuric glomerular diseases. Integrin-linked kinase (ILK) functions as a common downstream effector in proteinuric diseases. In addition, ILK was shown to interact with the Wnt signaling pathway. Here, we investigated ILK expression as well as its involvement with the Wnt signaling pathway in renal biopsies of patients with primary focal segmental glomerulosclerosis (FSGS), and in a correspondent in vivo model of podocyte lesion. METHODS: Biopsies from 37 patients with primary FSGS were evaluated by immunohistochemistry for ILK, phosphorylated GSK-3ß (pGSK-3ß) and ß-catenin expression. As experimental model, male Wistar rats received 5 injections of puromycin aminonucleoside (PAN) at 2-week intervals, and their kidneys were evaluated for ILK, P-cadherin and pAkt expression as well as ß-catenin and LEF-1 colocalization. RESULTS: Patients presented de novo ILK expression and pGSK-3ß in podocytes. In animals, there was an increase in gene and protein expression of ILK, mainly detected in the podocytes, as well as increased protein expression of pAkt compared with controls. ß-Catenin translocated to the nuclei of podocytes in animals and patients. ß-Catenin colocalized with LEF-1 in the nuclei of podocytes of animals. Gene expression of ß-catenin and P-cadherin in PAN rats was lower compared with controls. CONCLUSIONS: Our findings suggest that activation of ILK activated the Wnt signaling pathway in damaged podocytes. This phenomenon could have an important role in development and/or progression of clinical and experimental FSGS.

Should adolescents with glomerulopathies be treated as children or adults?

BACKGROUND: Glomerular diseases are an important cause of end-stage renal disease, especially among young adults. However, clinical and epidemiological surveys involving adolescent populations are scarce. AIM: To determine the pattern of glomerulopathies (GP) in adolescents submitted to renal biopsy. METHODS: A retrospective study of patients' records of the Glomerulopathy Section, UNIFESP (Brazil), was performed RESULTS: Among 72 adolescents (12-18 years) with GP, 15.6 +/- 1.5 years, 58.3% females, the most frequent clinical manifestation was nephrotic syndrome (NS, 71%) and focal segmental glomerulosclerosis (FSGS) was the main histological pattern (24%), followed by minimal change disease (MCD, 19.5%). After comparing the main causes of NS in adolescents with those of adults, we found no statistically significant differences in clinical presentation or outcome. Renal failure-free survival of 1 and 5 years for all GP corresponded to 87.9 and 73.6%, respectively (88.5 and 76.3% for NS). CONCLUSIONS: NS was the main manifestation; FSGS and MCD were the most common histological diagnoses. Our data suggest the GP and particularly the NS pattern in adolescents is similar to that of adults, pointing to the need for an adaptation in diagnostic and treatment protocols for this age group, a pattern which corresponds more closely to that of adults.