Update of the recommendations on the management of the SARS-CoV-2 coronavirus pandemic (COVID-19) in kidney transplant patients.

SARS-CoV-2 infection (COVID-19) has had a significant impact on transplant activity in our country. Mortality and the risk of complications associated with COVID-19 in kidney transplant recipients (KT) were expected to be higher due to their immunosuppressed condition and the frequent associated comorbidities. Since the beginning of the pandemic in March 2020 we have rapidly improved our knowledge about the epidemiology, clinical features and management of COVID-19 post-transplant, resulting in a better prognosis for our patients. KT units have been able to adapt their programs to this new reality, normalizing both donation and transplantation activity in our country. This manuscript presents a proposal to update the general recommendations for the prevention and treatment of infection in this highly vulnerable population such as KT.

Benefits of Routine Screening for Renal Cell Carcinoma of Native Kidney in Renal Transplant Recipients.

BACKGROUND: Renal-cell carcinoma (RCC) is the most common solid organ cancer in kidney transplantation recipients (KTRs). BACKGROUND: Analyze the incidence, prognosis, and evolution of primitive kidney RCC in KTRs at our institution. MATERIAL AND METHODS: Observational descriptive retrospective study in which all KTRs from January 2000 to December 2022 were included. We performed an annual abdominal ultrasound in all KTRs. Demographic and clinical data were collected. The surgical approach, location, size, histologic type, and tumor grade were analyzed. We assessed the coexistence of risk factors. We reported the appearance of tumors in other locations, changes in immunosuppressants (IS) after the diagnosis, and survival and recurrence rates observed during follow-up. RESULTS: Eighteen RCCs of native kidneys were diagnosed with an incidence in our population of 1.08%. The majority were men (77.8%), with a mean age of 59.9 years. The pathologic analysis revealed 11 clear cell carcinomas, 6 papillary carcinomas, and 1 chromophobe cell carcinoma. The median tumor size was 2.7 cm. TNM stage was T1aN0M0 in 15 cases. Laparoscopy was performed to remove the tumor in most cases. All our patients underwent changes in IS therapy, with conversion to mammalian target of rapamycin inhibitors when possible and reduction of IS in all of them. After a mean follow-up of 78.6 months, survival was 100% without tumor recurrence. Seven of the patients were diagnosed with a new tumor in another location. CONCLUSION: In our experience, annual abdominal ultrasound in KTRs may be an option for the early detection of RCC in native kidneys.

Actualización de las recomendaciones en el manejo de la pandemia por coronavirus SARS-CoV-2 (COVID-19) en pacientes con trasplante renal / Update of the recommendations on the management of the SARS-CoV-2 coronavirus pandemic (COVID-19) in kidney transplant patients

La infección por el SARS-CoV-2 (COVID-19) ha supuesto un importante impacto en la actividad trasplantadora en nuestro país. Era esperable que la mortalidad y el riesgo de complicaciones asociadas a la COVID-19 en el receptor de trasplante renal (TR) fueran mayores debido a su condición de inmunosupresión y a las frecuentes comorbilidades asociadas. Desde el inicio de la pandemia en marzo del 2020 hemos mejorado rápidamente nuestro conocimiento acerca de la epidemiología, características clínicas y manejo de la COVID-19 postrasplante, redundando en un mejor pronóstico para nuestros pacientes. Las unidades de TR han sabido adaptar sus programas a esta nueva realidad, normalizándose la actividad tanto de donación como de trasplante en nuestro país. Este manuscrito presenta una propuesta de actualización de las recomendaciones generales para la prevención y el tratamiento de la infección en esta población tan vulnerable como son los receptores de un trasplante renal. (AU)

SARS-CoV-2 infection (COVID-19) has had a significant impact on transplant activity in our country. Mortality and the risk of complications associated with COVID-19 in kidney transplant (KT) recipients were expected to be higher due to their immunosuppressed condition and the frequent associated comorbidities. Since the beginning of the pandemic in March 2020 we have rapidly improved our knowledge about the epidemiology, clinical features and management of COVID-19 post-transplant, resulting in a better prognosis for our patients. KT units have been able to adapt their programs to this new reality, normalizing both donation and transplantation activity in our country. This manuscript presents a proposal to update the general recommendations for the prevention and treatment of infection in this highly vulnerable population such as KT. (AU)

Management of immunosuppressive therapy in kidney transplant recipients with COVID-19. A multicentre national study derived from the Spanish Society of Nephrology COVID registry.

INTRODUCTION: SARS CoV2 infection has had a major impact on renal transplant patients with a high mortality in the first months of the pandemic. Intentional reduction of immunosuppressive therapy has been postulated as one of the cornerstone in the management of the infection in the absence of targeted antiviral treatment. This has been modified according to the patient`s clinical situation and its effect on renal function or anti-HLA antibodies in the medium term has not been evaluated. OBJECTIVES: Evaluate the management of immunosuppressive therapy made during SARS-CoV2 infection, as well as renal function and anti-HLA antibodies in kidney transplant patients 6 months after COVID19 diagnosis. MATERIAL AND METHODS: Retrospective, national multicentre, retrospective study (30 centres) of kidney transplant recipients with COVID19 from 01/02/20 to 31/12/20. Clinical variables were collected from medical records and included in an anonymised database. SPSS statistical software was used for data analysis. RESULTS: renal transplant recipients with COVID19 were included (62.6% male), with a mean age of 57.5 years. The predominant immunosuppressive treatment prior to COVID19 was triple therapy with prednisone, tacrolimus and mycophenolic acid (54.6%) followed by m-TOR inhibitor regimens (18.6%). After diagnosis of infection, mycophenolic acid was discontinued in 73.8% of patients, m-TOR inhibitor in 41.4%, tacrolimus in 10.5% and cyclosporin A in 10%. In turn, 26.9% received dexamethasone and 50.9% were started on or had their baseline prednisone dose increased. Mean creatinine before diagnosis of COVID19, at diagnosis and at 6 months was: 1.7 ±â€¯0.8, 2.1 ±â€¯1.2 and 1.8 ±â€¯1 mg/dl respectively (p < 0.001). 56.9% of the patients (N = 350) were monitored for anti-HLA antibodies. 94% (N = 329) had no anti-HLA changes, while 6% (N = 21) had positive anti-HLA antibodies. Among the patients with donor-specific antibodies post-COVID19 (N = 9), 7 patients (3.1%) had one immunosuppressant discontinued (5 patients had mycophenolic acid and 2 had tacrolimus), 1 patient had both immunosuppressants discontinued (3.4%) and 1 patient had no change in immunosuppression (1.1%), these differences were not significant. CONCLUSIONS: The management of immunosuppressive therapy after diagnosis of COVID19 was primarily based on discontinuation of mycophenolic acid with very discrete reductions or discontinuations of calcineurin inhibitors. This immunosuppression management did not influence renal function or changes in anti-HLA antibodies 6 months after diagnosis.

The use of lymphocyte-depleting antibodies in specific populations of kidney transplant recipients: A systematic review and meta-analysis.

BACKGROUND: Recommendations of the use of antibody induction treatments in kidney transplant recipients (KTR) are based on moderate quality and historical studies. This systematic review aims to reevaluate, based on actual studies, the effects of different antibody preparations when used in specific KTR subgroups. METHODS: We searched MEDLINE and CENTRAL and selected randomized controlled trials (RCT) and observational studies looking at different antibody preparations used as induction in KTR. Comparisons were categorized into different KTR subgroups: standard, high risk of rejection, high risk of delayed graft function (DGF), living donor, and elderly KTR. Two authors independently assessed the risk of bias. RESULTS: Thirty-seven RCT and 99 observational studies were finally included. Compared to anti-interleukin-2-receptor antibodies (IL2RA), anti-thymocyte globulin (ATG) reduced the risk of acute rejection at two years in standard KTR (RR 0.74, 95%CI 0.61-0.89) and high risk of rejection KTR (RR 0.55, 95%CI 0.43-0.72), but without decreasing the risk of graft loss. We did not find significant differences comparing ATG vs. alemtuzumab or different ATG dosages in any KTR group. CONCLUSIONS: Despite many studies carried out on induction treatment in KTR, their heterogeneity and short follow-up preclude definitive conclusions to determine the optimal induction therapy. Compared with IL2RA, ATG reduced rejection in standard-risk, highly sensitized, and living donor graft recipients, but not in high DGF risk or elderly recipients. More studies are needed to demonstrate beneficial effects in other KTR subgroups and overall patient and graft survival.

Manejo de la inmunosupresión en pacientes trasplantados de riñón con COVID19. Estudio multicéntrico nacional derivado del registro COVID de la Sociedad Española de Nefrología / Management of immunosuppressive therapy in kidney transplant recipients with COVID-19. A multicentre national study derived from the Spanish Society of Nephrology. COVID registry

Introducción: La infección por SARS-CoV2 ha impactado de forma importante en los pacientes con trasplante renal causando una elevada mortalidad en los primeros meses de la pandemia. La reducción intencionada de la inmunosupresión se ha postulado como uno de los pilares en el manejo de la infección ante la falta de un tratamiento antiviral dirigido. Esta se ha modificado de acuerdo con la situación clínica de los pacientes, y su efecto sobre la función renal o los anticuerpos anti-HLA a medio plazo no ha sido evaluado. Objetivos: Evaluar los cambios de inmunosupresión realizados durante la infección por SARS-CoV2, así como la función renal y los anticuerpos anti-HLA de los pacientes trasplantados de riñón a los 6 meses del diagnóstico de COVID19. Material y métodos: Estudio retrospectivo, multicéntrico nacional (30 centros) de pacientes trasplantados de riñón con COVID19 desde el 01/02/20 al 31/12/20. Se recogieron las variables de la historia clínica y se incluyeron en una base de datos anonimizada. Se utilizó el programa estadístico SPSS para el análisis de resultados. (AU)

Introduction: SARS-CoV-2 infection has had a major impact on renal transplant patients with a high mortality in the first months of the pandemic. Intentional reduction of immunosuppressive therapy has been postulated as one of the cornerstone in the management of the infection in the absence of targeted antiviral treatment. This has been modified according to the patient's clinical situation and its effect on renal function or anti-HLA antibodies in the medium term has not been evaluated. Objectives: Evaluate the management of immunosuppressive therapy made during SARS-CoV-2 infection, as well as renal function and anti-HLA antibodies in kidney transplant patients 6 months after COVID-19 diagnosis. Material and methods: Retrospective, national multicentre, retrospective study (30 centres) of kidney transplant recipients with COVID19 from 01/02/20 to 31/12/20. Clinical variables were collected from medical records and included in an anonymised database. SPSS statistical software was used for data analysis. (AU)

Changes over time in the causes of death with a functioning graft in kidney transplantation recipients.

INTRODUCTION: Death with a functioning graft (DWFG) is the most frequent cause of loss of kidney transplantation (KT). OBJECTIVE: To analyze the evolution of the causes of DWFG and the frequency of the types of cancer causing DWFG. METHODS: Retrospective study of KT in Andalusia from 1984 to 2018. We analyzed the evolution according to eras (1984-1995; 1996-2007; 2008-2018) and according to post-transplant period (early death: first year post-KT; late death: after first year post-KT). RESULTS: A total of 9905 KT were performed, registering 1861 DWFG. The most frequent causes were cardiovascular disease (25.1%), infections (21.5%) and cancer (19.9%). In early death we did not observe changes, and infections were always the main cause. In late death, cardiovascular death decreased (1984-1995: 35.2%, 1996-2007: 22.6%, 2008-2018: 23.9%), but infections (1984-1995: 12.5%, 1996-2007: 18.3%, 2008-2018: 19.9%) and, above all, cancer-related deaths increased (1984-1995: 21.8%, 1996-2007: 29%, 2008-2018: 26.8%) (P < .001). In the multivariable analysis for late death due to cardiovascular disease, recipient age, retransplantation, diabetes, and the first period were risk factors, while the risk of late death due to cancer and infections was associated with recent eras. In the first year after transplantation, the most frequent neoplasia causing DWFG was post-transplant lymphoproliferative disease, and after the first year, it was lung cancer, without differences when it was analyzed by eras. CONCLUSIONS: Despite the greater comorbidity of the recipients, cardiovascular deaths have decreased. Cancer has been the main cause of late death in recent years. Lung cancer is the most frequent malignancy that causes DWFG in our transplant patients.

Importance of physical exercise prescription in patients with chronic kidney disease: results of the survey of the Grupo Español Multidisciplinar de Ejercicio Físico en el Enfermo Renal [Spanish Multidisciplinary Group of Physical Exercise in Kidney Patients] (GEMEFER).

INTRODUCTION: Despite the benefits of physical exercise (PE) for patients with chronic kidney disease (CKD), the number of Nephrology services that have PE programs is limited. OBJECTIVES: To describe the degree of knowledge of PE benefits in patients with CKD among professionals, as well as the level of implementation and characteristics of PE programs in Nephrology services in Spain. METHODS: A questionnaire on the degree of knowledge and prescription of PE in patients with CKD was designed and sent to members of the Spanish Nephrology and Nephrology Nursing Societies, as well as to physiotherapists and professionals in the Sciences of Physical Activity and Sport (PASS). RESULTS: 264 professionals participated. 98.8% agreed on the importance of prescribing PE, but only 20.5% carry out an assessment of functional capacity and 19.3% have a PE program for patients with CKD in their centre. The most frequent programs are performed for haemodialysis patients and strength and aerobic resistance exercises are combined. A physiotherapist or a PASS usually participates in its prescription. The main barriers were the absence of human and/or physical resources and the lack of training. CONCLUSIONS: Healthcare workers know the benefits of PE in patients with CKD. However, the implementation of these programs in Spain is low, motivated by the lack of resources and training of professionals. We must establish strategies to guarantee an adequate functional capacity within the care of our patients.

Cambios en el tiempo de las causas de muerte con injerto funcionante en los receptores de trasplante renal / Changes over time in the causes of death with a functioning graft in kidney transplantation recipients

Introducción: La muerte con injerto funcionante (MCIF) es la causa más frecuente de pérdida del trasplante renal (TR). Objetivo: Analizar la evolución de las etiologías de MCIF y la frecuencia de los tipos de neoplasia causantes. Métodos: Estudio retrospectivo de los TR en Andalucía desde 1984 hasta 2018. Analizamos la evolución de las MCIF según etapas (1984-1995; 1996-2007; 2008-2018) y según período post-TR (muerte precoz: primer año post-TR; muerte tardía: tras el primer año post-TR). Resultados: Se realizaron 9.905 TR; se produjeron 1.861 MCIF. Las causas más frecuentes fueron enfermedad cardiovascular (25,1%), infecciones (21,5%) y neoplasias (19,9%). En las muertes precoces no observamos cambios en el tiempo; las infecciones siempre fueron la causa principal. En las tardías, desciende la muerte cardiovascular (1984-1995: 35,2%; 1996-2007: 22,6%; 2008-2018: 23,9%) y aumentan las muertes por infecciones (1984-1995: 12,5%; 1996-2007: 18,3%; 2008-2018: 19,9%) y, sobre todo, por cáncer (1984-1995: 21,8%; 1996-2007: 29%; 2008-2018: 26,8%) (p<0,001). En el análisis multivariante para muerte tardía cardiovascular, edad del receptor, retrasplante, diabetes y primera etapa fueron factores de riesgo, mientras que el riesgo de muerte tardía por cáncer e infecciones se asoció con las etapas recientes. La neoplasia más frecuente en el primer año post-TR fue la enfermedad linfoproliferativa post-TR y tras el primer año el cáncer de pulmón, sin diferencias entre etapas. Conclusiones: A pesar de la mayor comorbilidad del receptor, las muertes cardiovasculares han descendido. Las neoplasias son la principal causa de muerte tardía en los últimos años. El cáncer de pulmón es la neoplasia más frecuente causante de MCIF en TR. (AU)

Introduction: Death with a functioning graft (DWFG) is the most frequent cause of loss of kidney transplantation (KT). Objective: To analyze the evolution of the causes of DWFG and the frequency of the types of cancer causing DWFG. Methods: Retrospective study of KT in Andalusia from 1984 to 2018. We analyzed the evolution according to eras (1984-1995; 1996-2007; 2008-2018) and according to post-transplant period (early death: first year post-KT; late death: after first year post-KT). Results: A total of 9,905 KT were performed, registering 1,861 DWFG. The most frequent causes were cardiovascular disease (25.1%), infections (21.5%) and cancer (19.9%). In early death we did not observe changes, and infections were always the main cause. In late death, cardiovascular death decreased (1984-1995: 35.2%, 1996-2007: 22.6%, 2008-2018: 23.9%), but infections (1984-1995: 12.5%, 1996-2007: 18.3%, 2008-2018: 19.9%) and, above all, cancer-related deaths increased (1984-1995: 21.8%, 11996-2007: 29%, 2008-2018: 26.8%) (P<0.001). In the multivariable analysis for late death due to cardiovascular disease, recipient age, retransplantation, diabetes, and the first period were risk factors, while the risk of late death due to cancer and infections was associated with recent eras. In the first year after transplantation, the most frequent neoplasia causing DWFG was post-transplant lymphoproliferative disease, and after the first year, it was lung cancer, without differences when it was analyzed by eras. Conclusions: Despite the greater comorbidity of the recipients, cardiovascular deaths have decreased. Cancer has been the main cause of late death in recent years. Lung cancer is the most frequent malignancy that causes DWFG in our transplant patients. (AU)

Importancia de la prescripción de ejercicio físico en pacientes con enfermedad renal crónica: resultados de la encuesta del Grupo Español Multidisciplinar de Ejercicio Físico en el Enfermo Renal (GEMEFER) / Importance of physical exercise prescription in patients with chronic kidney disease: Results of the survey of the Spanish Multidisciplinary Group of Physical Exercise in Kidney Patients (GEMEFER)

Introducción: A pesar de los beneficios del ejercicio físico (EF) para pacientes con enfermedad renal crónica (ERC), el número de servicios de Nefrología que han implementado programas de EF es limitado. Objetivos: Describir el grado de conocimiento del EF en pacientes con ERC entre los profesionales, así como el nivel de implementación y las características de los programas de EF en los servicios de Nefrología en España. Métodos: Se diseñó un cuestionario sobre el grado de conocimiento y de prescripción del EF en pacientes con ERC que se envió a los socios de la Sociedad Española de Nefrología y de la Sociedad Española de Enfermería Nefrológica, así como a fisioterapeutas y profesionales de las Ciencias de la Actividad Física y del Deporte (CAFyD). Resultados: Participaron 264 profesionales. El 98,8% coincidían en la importancia de prescribir EF, pero solo el 20,5% realizan una valoración de la capacidad funcional y solo el 19,3% disponen de un programa de EF para pacientes con ERC en su centro. Los programas más frecuentes están dirigidos a pacientes en hemodiálisis y combinan ejercicios de fuerza y de resistencia aeróbica. En la prescripción habitualmente interviene un fisioterapeuta o un CAFyD. Las principales barreras fueron la ausencia de recursos humanos y/o físicos y la falta de formación. Conclusiones: Los profesionales sanitarios conocen los beneficios del EF en el paciente renal. Sin embargo, la implementación de estos programas en España es baja, debido a la falta de recursos y a la falta de formación de los profesionales. Debemos establecer estrategias para garantizar una adecuada capacidad funcional dentro de los cuidados de nuestros pacientes. (AU)

Introduction: Despite the benefits of physical exercise (PE) for patients with chronic kidney disease (CKD), the number of Nephrology services that have PE programs is limited. Objective: To describe the degree of knowledge of PE benefits in patients with CKD among professionals, as well as the level of implementation and characteristics of PE programs in Nephrology services in Spain. Methods: A questionnaire on the degree of knowledge and prescription of PE in patients with CKD was designed and sent to members of the Spanish Nephrology and Nephrology Nursing Societies, as well as to physiotherapists and professionals in the Sciences of Physical Activity and Sport (CAFyD). Results: 264 professionals participated. 98.8% agreed on the importance of prescribing PE, but only 20.5% carry out an assessment of functional capacity and 19.3% have a PE program for patients with CKD in their center. The most frequent programs are performed for hemodialysis patients and strength and aerobic resistance exercises are combined. A physiotherapist or a CAFyD usually participates in its prescription. The main barriers were the absence of human and/or physical resources and the lack of training. Conclusions: Healthcare workers know the benefits of PE in patients with CKD. However, the implementation of these programs in Spain is low, motivated by the lack of resources and training of professionals. We must establish strategies to guarantee an adequate functional capacity within the care of our patients. (AU)

Induction immunosuppression and outcome in kidney transplant recipients with early COVID-19 after transplantation.

Coronavirus disease 2019 (COVID-19) in kidney transplant recipients has a high risk of complications and mortality, especially in older recipients diagnosed during the early period after transplantation. Management of immunosuppression has been challenging during the pandemic. We investigated the impact of induction immunosuppression, either basiliximab or thymoglobulin, on the clinical evolution of kidney transplant recipients developing COVID-19 during the early period after transplantation. We included kidney transplant recipients with ˂6 months with a functioning graft diagnosed with COVID-19 from the initial pandemic outbreak (March 2020) until 31 July 2021 from different Spanish centres participating in a nationwide registry. A total of 127 patients from 17 Spanish centres developed COVID-19 during the first 6 months after transplantation; 73 (57.5%) received basiliximab and 54 (42.5%) thymoglobulin. Demographics were not different between groups but patients receiving thymoglobulin were more sensitized [calculated panel reactive antibodies (cPRAs) 32.7 ± 40.8% versus 5.6 ± 18.5%] and were more frequently retransplants (30% versus 4%). Recipients ˃65 years of age treated with thymoglobulin showed the highest rate of acute respiratory distress syndrome [64.7% versus 37.1% for older recipients receiving thymoglobulin and basiliximab (P < .05), respectively, and 23.7% and 18.9% for young recipients receiving basiliximab and thymoglobulin (P > .05)], respectively, and the poorest survival [mortality rate 64.7% and 42.9% for older recipients treated with thymoglobulin and basiliximab, respectively (P < .05) and 8.1% and 10.5% for young recipients treated with thymoglobulin and basiliximab (P > .05), respectively]. Older recipients treated with thymoglobulin showed the poorest survival in the Cox regression model adjusted for comorbidities. Thus thymoglobulin should be used with caution in older recipients during the present pandemic era.

[Update of the recommendations on the management of the SARS-CoV-2 coronavirus pandemic (COVID-19) in kidney transplant patients.] / Actualización de las recomendaciones en el manejo de la pandemia por coronavirus SARS-CoV-2 (COVID-19) en pacientes con trasplante renal.

SARS-CoV-2 infection (COVID-19) has had a significant impact on transplant activity in our country. Mortality and the risk of complications associated with COVID-19 in kidney transplant recipients (KT) were expected to be higher due to their immunosuppressed condition and the frequent associated comorbidities. Since the beginning of the pandemic in March 2020 we have rapidly improved our knowledge about the epidemiology, clinical features and management of COVID-19 post-transplant, resulting in a better prognosis for our patients. KT units have been able to adapt their programs to this new reality, normalizing both donation and transplantation activity in our country.This manuscript presents a proposal to update the general recommendations for the prevention and treatment of infection in this highly vulnerable population such as KT.

Treatment with sotrovimab for SARS-CoV-2 infection in a cohort of high-risk kidney transplant recipients.

Background: Sotrovimab is a neutralizing monoclonal antibody (mAb) that seems to remain active against recent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. The evidence on its use in kidney transplant (KT) recipients, however, is limited. Methods: We performed a multicenter, retrospective cohort study of 82 KT patients with SARS-CoV-2 infection {coronavirus disease 2019 [COVID-19]} treated with sotrovimab. Results: Median age was 63 years. Diabetes was present in 43.9% of patients, and obesity in 32.9% of patients; 48.8% of patients had an estimated glomerular filtration rate under 30 mL/minute/1.73 m2. Additional anti-COVID-19 therapies were administered to 56 patients, especially intravenous steroids (65.9%). Sotrovimab was administered early (<5 days from the onset of the symptoms) in 46 patients (56%). Early-treated patients showed less likely progression to severe COVID-19 than those treated later, represented as a lower need for ventilator support (2.2% vs 36.1%; P < .001) or intensive care admission (2.2% vs 25%; P = .002) and COVID-19-related mortality (2.2% vs 16.7%; P = .020). In the multivariable analysis, controlling for baseline risk factors to severe COVID-19 in KT recipients, early use of sotrovimab remained as a protective factor for a composite outcome, including need for ventilator support, intensive care, and COVID-19-related mortality. No anaphylactic reactions, acute rejection episodes, impaired kidney function events, or non-kidney side effects related to sotrovimab were observed. Conclusions: Sotrovimab had an excellent safety profile, even in high-comorbidity patients and advanced chronic kidney disease stages. Earlier administration could prevent progression to severe disease, while clinical outcomes were poor in patients treated later. Larger controlled studies enrolling KT recipients are warranted to elucidate the true efficacy of monoclonal antibody therapies.