Tubulo-interstitial inflammation increases the risk of graft loss after the recurrence of IgA nephropathy.

Background: Immunoglobulin A nephropathy (IgAN) is the most frequent recurrent disease in kidney transplant recipients and its recurrence contributes to reducing graft survival. Several variables at the time of recurrence have been associated with a higher risk of graft loss. The presence of clinical or subclinical inflammation has been associated with a higher risk of kidney graft loss, but it is not precisely known how it influences the outcome of patients with recurrent IgAN. Methods: We performed a multicentre retrospective study including kidney transplant recipients with biopsy-proven recurrence of IgAN in which Banff and Oxford classification scores were available. 'Tubulo-interstitial inflammation' (TII) was defined when 't' or 'i' were ≥2. The main endpoint was progression to chronic kidney disease (CKD) stage 5 or to death censored-graft loss (CKD5/DCGL). Results: A total of 119 kidney transplant recipients with IgAN recurrence were included and 23 of them showed TII. Median follow-up was 102.9 months and 39 (32.8%) patients reached CKD5/DCGL. TII related to a higher risk of CKD5/DCGL (3 years 18.0% vs 45.3%, log-rank 7.588, P = .006). After multivariate analysis, TII remained related to the risk of CKD5/DCGL (HR 2.344, 95% CI 1.119-4.910, P = .024) independently of other histologic and clinical variables. Conclusions: In kidney transplant recipients with IgAN recurrence, TII contributes to increasing the risk of CKD5/DCGL independently of previously well-known variables. We suggest adding TII along with the Oxford classification to the clinical variables to identify recurrent IgAN patients at increased risk of graft loss who might benefit from intensified immunosuppression or specific IgAN therapies.

Development of an Information Guideline for Kidney Transplant Recipients in a Clinical Trial: Protocol for a Modified Delphi Method.

BACKGROUND: Renal transplantation is the treatment of choice for most cases of end-stage renal disease. Recipients need to lead a healthy lifestyle to minimize the potential side effects of immunosuppressive drugs and improve transplant outcomes. There is not much evidence about the best way to increase adherence to healthy lifestyles in kidney transplant recipients, so one of the objectives set by the nursing team is to train people to acquire the necessary skills and tools to be able to take care of themselves. In this sense, the consensual development of appropriate materials may be useful and of interest. OBJECTIVE: The aim of this study was to develop an information guide for adults with kidney transplants to be assessed in a subsequent clinical trial as an intervention to increase adherence to healthy habits. METHODS: We used a 3-step, methodological, sequential approach: (1) training from a group of experts and item consensus; (2) review of the medical literature available; and (3) use of the Delphi technique with on-site meetings. A total of 5 nurses from the Community of Madrid Kidney Transplantation Unit in Spain were asked to participate. The patients' lifestyle factors that, according to the medical literature available and experts' opinions, have the greatest impact on the survival of the transplanted organ and the recipients themselves were all described. RESULTS: After using the modified Delphi method to reach a consensus on the items to be included and the information needed in each, an information guide for adult kidney transplant patients was developed. This guide facilitates the structuring of health care, information, and recommendations necessary for effective self-care for each person. The result is considered to be an easy-to-understand tool, useful for transplant doctors and nurses, in simple language, with information based on the latest scientific-medical evidence published to date, aspects of which will be evaluated in a clinical trial designed for this purpose. CONCLUSIONS: Currently, this guide is the main intervention variable of a clinical trial (registered on ClinicalTrials.gov; NCT05715580) aimed at improving compliance with healthy habits in kidney transplant recipients in the Community of Madrid, Spain. The method used in its development has been useful and agile, and the result is a guide that can be easily updated periodically following the same procedure. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/46961.

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.

Enfermedad linfoproliferativa difusa postrasplante renal: estudio longitudinal de 21.546 receptores durante 2 décadas en España / Lymphoproliferative disorders after renal transplantation along 2 decades: A large longitudinal study of 21.546 recipients

Introducción: La enfermedad linfoproliferativa difusa postrasplante (ELPD) es un grupo heterogéneo de enfermedades que se caracteriza por una proliferación de linfocitos después de un trasplante de órgano sólido y que presenta un espectro que comprende desde hiperplasias a agresivos linfomas. Material y métodos: Hemos evaluado, en un estudio observacional multicéntrico retrospectivo que incluye 21.546 receptores adultos de trasplante renal simple trasplantados en España de 1990 al 2009, la incidencia de ELPD durante un periodo de 22 años, su relación con el virus de Epstein-Barr, los factores de riesgo clásico y su pronóstico. Resultados: Un total de 275 receptores desarrollaron ELPD durante el seguimiento (1,2%), siendo 195 varones (70,9%) y 80 mujeres (29,1%), con una mediana de edad al diagnóstico de 59,2 (p25 44,7; p75 68) años. Doscientos cuarenta y cinco (89,0%) eran primeros trasplantes y 269 (97,8%) fueron de donante cadáver. Se objetivó virus de Epstein-Barr en el tejido proliferativo de 94 de los 155 casos estudiados (60,6%) y el 86,0% de las proliferaciones eran linfocitos B. La mediana del tiempo de desarrollo después del trasplante fue de 42 (p25 12; p75 77,5) meses. Un total de 188 receptores de 275 (68,3%) tenían algún factor de riesgo clásico. La incidencia anual fue de 0,14% el primer año y de 0,98% la acumulada en 10 años postrasplante. El periodo de seguimiento postrasplante de los receptores fue de 3 a 22 años. Durante el seguimiento 172 pacientes murieron (62,5%) y 103 (37,5%) tuvieron remisión completa. La causa de muerte más frecuente fue la progresión (n=91, 52,9%), seguida de la sepsis (n=24, 13,9%). La supervivencia del paciente después del diagnóstico fue del 51% al año, del 44% al segundo año y del 39% al quinto año. La supervivencia del injerto fue de 48, 39 y 33%, respectivamente. (AU)

Introduction: Posttransplant lymphoproliferative disorders (PTLD) are heterogeneous lymphoid proliferations in recipients of solid organs which seem to be related to Epstein-Barr virus. The use of antilymphocyte antibodies, Epstein-Barr virus seronegativity in the recipient, acute rejection and CMV infection have been identified as classical risk factors. Material and methods: We have studied, in a retrospective observational study, the incidence of PTLD in a period of 22 years, its relationship with Epstein-Barr virus, presence of classical risk factors and outcome in 21,546 simple adult renal transplant recipients from cadaveric and living donors, transplanted in 21 hospitals from 1990 to 2009. Results: A total of 275 recipients developed PTLD (1.2%), 195 males (70.9%), 80 females (29.1%), aged 59.2 (p25 44.7; p75 68) years. Two hundred forty-five (89.0%) were first transplant recipients and 269 (97.8%) from cadaveric donors. Epstein-Barr virus in the tissue was reported in 94 out of the 155 studied recipients (60.6%) and 86.0% of the proliferations were due to B lymphocytes. PTLD median appearance after transplant were 42 (p25 12; p75 77.5) months. One hundred eighty-eight recipients out of 275 patients (68.3%) had any classical risk factor and the use of antilymphocyte antibodies was the most frequent. During the follow-up, 172 patients died (62.5%) and 103 (37.5%) had a complete remission. The main cause of death was PTLD progression (n=91, 52,9%), followed by sepsis (n=24, 13.9%). The follow-up period post-transplant of the recipients was between 3 and 22 years. The incidence was 0.14% during the first year post-trasplant and 0.98% the cumulative incidence at 10 years. Patient survival after diagnosis was 51, 44 and 39% after one, 2 and 5 years, respectively. Finally, overall graft survival was 48, 39 and 33% at the same periods. (AU)

Sodium-glucose cotransporter-2 inhibitor therapy in kidney transplant patients with type 2 or post-transplant diabetes: an observational multicentre study.

Background: Sodium-glucose cotransporter-2 inhibitors (SGLT2is) have cardioprotective and renoprotective effects. However, experience with SGLT2is in diabetic kidney transplant recipients (DKTRs) is limited. Methods: This observational multicentre study was designed to examine the efficacy and safety of SGLT2is in DKTRs. The primary outcome was adverse effects within 6 months of SGLT2i treatment. Results: Among 339 treated DKTRs, adverse effects were recorded in 26%, the most frequent (14%) being urinary tract infection (UTI). In 10%, SGLT2is were suspended mostly because of UTI. Risk factors for developing a UTI were a prior episode of UTI in the 6 months leading up to SGLT2i use {odds ratio [OR] 7.90 [confidence interval (CI) 3.63-17.21]} and female sex [OR 2.46 (CI 1.19-5.03)]. In a post hoc subgroup analysis, the incidence of UTI emerged as similar in DKTRs treated with SGLT2i for 12 months versus non-DKTRs (17.9% versus 16.7%). Between baseline and 6 months, significant reductions were observed in body weight [-2.22 kg (95% CI -2.79 to -1.65)], blood pressure, fasting glycaemia, haemoglobin A1c [-0.36% (95% CI -0.51 to -0.21)], serum uric acid [-0.44 mg/dl (95% CI -0.60 to -0.28)] and urinary protein:creatinine ratio, while serum magnesium [+0.15 mg/dl (95% CI 0.11-0.18)] and haemoglobin levels rose [+0.44 g/dl (95% CI 0.28-0.58]. These outcomes persisted in participants followed over 12 months of treatment. Conclusions: SGLT2is in kidney transplant offer benefits in terms of controlling glycaemia, weight, blood pressure, anaemia, proteinuria and serum uric acid and magnesium. UTI was the most frequent adverse effect. According to our findings, these agents should be prescribed with caution in female DKTRs and those with a history of UTI.

Novel Drugs for the Management of Diabetes Kidney Transplant Patients: A Literature Review.

The management of diabetes and renal failure is changing thanks to the appearance of new drugs such as glucagon-like peptide 1 receptor agonists (GLP1-RA) and sodium-glucose cotransporter type 2 inhibitors (SGLT2i) that have benefits in terms of survival and cardiorenal protection. Based on the potential mechanisms of GLP1-RA, kidney transplant recipients (KTRs) could benefit from their effects. However, high-quality studies are needed to demonstrate these benefits, in the transplant population, especially those related to cardiovascular benefits and renal protection. Studies with SGLT2i performed in KTRs are much less potent than in the general population and therefore no benefits in terms of patient or graft survival have been clearly demonstrated in this population to date. Additionally, the most frequently observed side effects could be potentially harmful to this population profile, including severe or recurrent urinary tract infections and impaired kidney function. However, benefits demonstrated in KTRs are in line with a known potential effects in cardiovascular and renal protection, which may be essential for the outcome of transplant recipients. Better studies are still needed to confirm the benefits of these new oral antidiabetics in the renal transplant population. Understanding the characteristics of these drugs may be critical for KTRs to be able to benefit from their effects without being damaged. This review discusses the results of the most important published studies on KTRs with GLP1-RA and SGLT2i as well as the potential beneficial effects of these drugs. Based on these results, approximate suggestions for the management of diabetes in KTRs were developed.

Role of mTOR inhibitor in the cellular and humoral immune response to a booster dose of SARS-CoV-2 mRNA-1273 vaccine in kidney transplant recipients.

Background: Immunocompromised patients have an increased risk of developing severe COVID disease, as well as a tendency to suboptimal responses to vaccines. The objective of this study was to evaluate the specific cellular and humoral adaptive immune responses of a cohort of kidney transplant recipients (KTR) after 3 doses of mRNA-1273 vaccine and to determinate the main factors involved. Methods: Prospective observational study in 221 KTR (149 non infected), 55 healthy volunteers (HV) and 23 dialysis patients (DP). We evaluated anti-spike (by quantitative chemiluminescence immunoassay) and anti-nucleocapsid IgG (ELISA), percentage of TCD4+ and TCD8+ lymphocytes producing IFNγ against S-protein by intracellular flow cytometry after Spike-specific 15-mer peptide stimulation and serum neutralizing activity (competitive ELISA) at baseline and after vaccination. Results: Among COVID-19 naïve KTR, 54.2% developed cellular and humoral response after the third dose (vs 100% in DP and 91.7% in HV), 18% only showed cell-mediated response, 22.2% exclusively antibody response and 5.6% none. A correlation of neutralizing activity with both the IgG titer (r=0.485, p<0.001) and the percentage of S-protein-specific IFNγ-producing CD8-T cells (r=0.198, p=0.049) was observed. Factors related to the humoral response in naïve KTR were: lymphocytes count pre-vaccination >1000/mm3 [4.68 (1.72-12.73, p=0.003], eGFR>30 mL/min [7.34(2.72-19.84), p<0.001], mTOR inhibitors [6.40 (1.37-29.86), p=0.018]. Infected KTR developed a stronger serologic response than naïve patients (96.8 vs 75.2%, p<0.001). Conclusions: KTR presented poor cellular and humoral immune responses following vaccination with mRNA-1273. The immunosuppression degree and kidney function of these patients play an important role, but the only modifiable factor with a high impact on humoral immunogenicity after a booster dose was an immunosuppressive therapy including a mTOR inhibitor. Clinical trials are required to confirm these results.

Genome-wide association study biomarkers in T-cell mediated rejection: selective effect according to the Banff classification.

BACKGROUND: A genome-wide association study (GWAS) in kidney transplant recipients reported the association of two polymorphisms located in the PTPRO gene and upstream of the CCDC67 (DEUP1) gene with increased risk of acute T cell-mediated rejection (TCMR). We aimed at replicating the assessment of mentioned associations and additionally ascertaining the influence of treatment and clinical features of the patients. METHODS: The polymorphisms, PTPRO-rs7976329 and CCDC67-rs10765602 were genotyped by TaqMan chemistry in 641 consecutive kidney transplant recipients. The diagnosis of rejection was confirmed by biopsy and categorized according to the Banff classification. Associations were evaluated by Chi-square test or Fisher's exact test when necessary and multivariate logistic regression. RESULTS: Considering the GWAS study we only replicated the association of the PTPRO-rs7976329*C allele in the Banff grade < II subjects. However, the homozygous mutant genotypes of both polymorphism seemed to increase the risk of TCMR Banff grade < II in the overall cohort and after stratification by Thymoglobulin induction therapy. In the multivariate analysis, we confirmed the association of PTPRO-rs7976329 with TCMR Banff grade < II, independently of the Thymoglobulin induction therapy and of CCDC67-rs10765602 only in the group of patients not receiving Thymoglobulin induction therapy. No association of these polymorphisms with TCMR Banff grade ≥ II was observed in either the overall cohort or in the subgroups stratified by Thymoglobulin therapy. CONCLUSIONS: Our study shows that the increased risk of TCMR related to polymorphisms PTPRO-rs7976329 and CCDC67-rs10765602 previously reported in a GWAS was replicated only in homozygous patients who presented TCMR Banff grade < II and for the minor allele of either polymorphism.

[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.

Enfermedad antimembrana basal glomerular en hermanos no gemelos con HLA idéntico / Anti-glomerular basement membrane disease in HLA-identical non-twin siblings

La enfermedad antimembrana basal glomerular (EMBG) es un trastorno autoinmune caracterizado por la presencia de anticuerpos antimembrana basal glomerular (AMBG), hemorragia pulmonar, glomerulonefritis necrotizante y depósito lineal de inmunoglobulinas en inmunofluorescencia directa. La predisposición genética, entre otros factores, posee un papel importante en el desarrollo de la enfermedad. Estudios previos han demostrado que el antígeno leucocitario humano (HLA), HLA-DR15 y HLA- DR4, se asocian con mayor riesgo de presentarla, mientras que el HLA-DR1 y HLA-DR7 han demostrado ser factor de protección frente a su desarrollo.Describimos el primer caso de dos hermanos no gemelos con EMBG con tipaje HLA idéntico, con factor de riesgo HLA-DR4 y factor de protección HLA-DR7. Planteamos la importancia de analizar el tipaje de histocompatibilidad en hermanos de pacientes con EMBG, para determinar el grado de susceptibilidad genética y plantear en ellos un seguimiento estrecho, con el objetivo de lograr un diagnóstico y tratamiento precoces en caso de presentar la enfermedad. (AU)

Anti-glomerular basement membrane disease (AGBM) is an autoinmune disorder characterized by the presence of anti-glomerular basement membrane (anti-GBM) antibodies, alveolar hemorrhage, necrotizing glomerulonephritis, and linear deposition of immunoglobulins through direct inmunofluorescence. Genetic predisposition, among other factors, plays an important role in the development of the disease. Previous studies have shown that HLA-DR15 and HLA-DR4 increase the risk of presenting it, while HLA-DR1 and HLA-DR7 protect against its development.We describe the first case of two non-twin siblings with AGBM and identical HLA, with HLA-DR4 as risk factor and HLA-DR7 as protection factor. We propose the importance of analyzing HLA in siblings of patients with AGBM, to determine the degree of genetic susceptibility and to carry out a close follow-up on them, with the aim of achieving an early diagnosis and treatment in case of presenting the disease. (AU)

Clinical Effectiveness of SARS-CoV-2 Vaccination in Renal Transplant Recipients. Antibody Levels Impact in Pneumonia and Death.

BACKGROUND: Few studies have described the clinical impact of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines in renal transplant recipients (RTRs) in the context of omicron variant and the third vaccine dose. Antibody titer has been tried to relate to the prediction of outcomes related to SARS-CoV-2, but it results controversially in these populations. METHODS: All patients with positive SARS-CoV-2 polymerase chain reaction followed at a RTRs reference center from March 15, 2020, to March 15, 2022, were considered for analysis. Cases were analyzed by vaccination status. Breakthrough cases were then analyzed by nonantibodies (<20 arbitrary unit [AU]/mL), low (20-100 AU/mL), and high antibody titers (>100 AU/mL) against SARS-CoV-2 spike protein. Outcomes included pneumonia and mortality. We used logistic regression multivariable to assess for confounders. RESULTS: Among 186 RTRs with coronavirus disease 2019, 50.5% (n = 94) were vaccinated versus 49.5% (n = 92) unvaccinated. Of the vaccinated patients, 67.02% developed a high antibody titer (>100 AU/mL) but 14.89% achieved a low antibody titer and 18.08% nonantibodies. Pneumonia-free survival (day 20) was 95% in high antibody titer but 40% in unvaccinated RTRs. Survival in RTRs at day 60 was similar in the unvaccinated group compared with nonantibodies breakthrough cases (82%) but 92% in the low antibody titer group (relative risk, 0.027; 95% confidence interval, 0.002-0.479; P = 0.014). Only patients with >100 AU/mL showed a 100% survival on day 60 postinfection. CONCLUSIONS: Vaccinated RTRs who achieve at least a low antibody titer (>20 AU/mL) had better results in terms of pneumonia and mortality than unvaccinated RTRs. Antibody titer >100 AU/mL associate with even better results than patients with lower antibody titers.

Bioavailability of once-daily tacrolimus formulations used in clinical practice in the management of De Novo kidney transplant recipients: the better study.

Multicenter, prospective, observational study to compare the relative bioavailability of once-daily tacrolimus formulations in de novo kidney transplant recipients. De novo kidney transplant recipients who started a tacrolimus-based regimen were included 14 days post-transplant and followed up for 6 months. Data from 218 participants were evaluated: 129 in the LCPT group (Envarsus) and 89 in the PR-Tac (Advagraf) group. Patients in the LCPT group exhibited higher relative bioavailability (Cmin /total daily dose [TDD]) vs. PR-Tac (61% increase; P < .001) with similar Cmin and 30% lower TDD levels (P < .0001). The incidence of treatment failure was 3.9% in the LCPT group and 9.0% in the PR-Tac group (P = .117). Study discontinuation rates were 6.2% in the LCPT group and 12.4% in the PR-Tac group (P = .113). Adverse events, renal function and other complications were comparable between groups. The median accumulated dose of tacrolimus in the LCPT group from day 14 to month 6 was 889 mg. Compared to PR-Tac, LCPT showed higher relative bioavailability, similar effectiveness at preventing allograft rejection, comparable effect on renal function, safety, adherence, treatment failure and premature discontinuation rates.

Severe Acute Kidney Injury Due to Intraglomerular Melanoma: A Case Report.

Metastatic disease in the kidney is relatively uncommon compared to other body sites. In most cases it presents as a unilateral and unifocal mass in the tubulointerstitial region. Intraglomerular metastases are even rarer, and their diagnosis is hampered by the limitations of imaging techniques in detecting them. We describe the finding of intraglomerular metastases in a patient affected by a malignant melanoma considered to be in partial remission, with no evidence of melanoma progression on the previously performed computed tomography scan. This patient developed rapidly progressive kidney failure, proteinuria, and hematuria with dysmorphic red blood cells in the urine sediment. Kidney biopsy showed a marked crescentic proliferation caused by tumor cells, which even invaded the proximal convoluted tubule. Melanoma cells were also found in the lumina of the glomerular capillaries, distending their basement membranes. Our case describes the histologic and electron microscopic findings of this form of intraglomerular metastasis and reminds us of its inclusion in the differential diagnosis of rapidly progressive kidney failure.

Anti-glomerular basement membrane disease in HLA-identical non-twin siblings.

Anti glomerular basement membrane disease (AGBM) is an autoinmune disorder characterised by the presence of anti-glomerular basement membrane (Anti-GBM) antibodies, alveolar hemorrhage, necrotizing glomerulonephritis, and linear deposition of immunoglobulins through direct inmunofluorescence. Genetic predisposition, among other factors, plays an important role in the development of the disease. Previous studies have shown that HLA-DR15 and HLA-DR4 increase the risk of presenting it, while HLA-DR1 and HLA-DR7 protect against its development. We describe the first case of two non-twin siblings with AGBM and identical HLA, with HLA-DR4 as risk factor and HLA-DR7 as protection factor. We propose the importance of analysing HLA in siblings of patients with AGBM, to determine the degree of genetic susceptibility and to carry out a close follow-up on them, with the aim of achieving an early diagnosis and treatment in case of presenting the disease.

Hemophagocytic syndrome triggered by donor-transmitted toxoplasmosis as a complication in same-donor recipients of renal transplantation: Case report and review of the literature.

BACKGROUND: Hemophagocytic syndrome (HPS) is an infrequent complication of transplantation caused by an inflammatory response with a benign proliferation of macrophages and defective lytic capability of T lymphocytes and NK cells that can lead to multiorgan failure. Transplant patients are particularly exposed as a result of the increased risk of both infections and malignancies derived from immunosuppressive drugs. There is no consensus for therapy or immunosuppression; mortality is high. We report a case and present a review of all cases of HPS occurring in solid organ transplant recipients.  CASE REPORT: We report two cases of infection by Toxoplasma gondii transmitted by the kidney allograft. One of the recipients was seronegative before transplantation and developed disseminated primary toxoplasmosis. An immune reaction compatible with an HPS ensued. Both were treated with Trimethoprim/sulfamethoxazole, immunosuppression was tapered, and after a 2-week period a complete response was obtained. CONCLUSION: HPS presents therapeutic challenges in the context of transplantation. If HPS is suspected, the search of a very likely underlying infection should be central to the management.