Relationship of hemoglobin levels with outcomes in deceased donor kidney transplant: a retrospective cohort study / Relação dos níveis de hemoglobina com desfechos em transplante renal de doador falecido: um estudo de coorte retrospectivo

ABSTRACT Introduction: Anemia is frequent in patients undergoing replacement therapy for kidney failure. Anemia in the pre- and post-transplantation period might be related to kidney transplant outcomes. The current study therefore sought to assess the relationship between anemia, delayed allograft function (DGF), chronic kidney allograft dysfunction (CAD), and death from any cause following kidney transplantation from a deceased donor. Methods: This was a retrospective study with 206 kidney transplant patients of deceased donors. We analyzed deceased donors' and kidney transplant patients' demographic data. Moreover, we compared biochemical parameters, anemia status, and medicines between DGF and non-DGF groups. Afterward, we performed a multivariate analysis. We also evaluated outcomes, such as CAD within one year and death in ten years. Results: We observed a lower frequency of pre-transplant hemoglobin concentration (Hb) but higher frequency of donor-serum creatinine and red blood transfusion within one week after transplantation in the group with DGF. In addition, there was an independent association between Hb concentration before transplantation and DGF [OR 0.252, 95%CI: 0.159-0.401; p < 0.001]. There was also an association between Hb concentration after six months of kidney transplantation and both CAD [OR 0.798, 95% CI: 0.687-0.926; p = 0.003] and death from any cause. Conclusion: An association was found between pre-transplantation anemia and DGF and between anemia six months after transplantation and both CAD and death by any cause. Thus, anemia before or after transplantation affects the outcomes for patients who have undergone kidney transplantation from a deceased donor.

RESUMO Introdução: A anemia é frequente em pacientes submetidos à terapia substitutiva para insuficiência renal. A anemia nos períodos pré e pós-transplante pode estar relacionada aos desfechos do transplante renal. Portanto, o presente estudo buscou avaliar a relação entre anemia, função retardada do enxerto (FRE), disfunção crônica do enxerto renal (DCE) e óbito por qualquer causa após transplante renal de doador falecido. Métodos: Este foi um estudo retrospectivo com 206 pacientes transplantados renais de doadores falecidos. Analisamos dados demográficos de doadores falecidos e pacientes transplantados renais. Além disso, comparamos parâmetros bioquímicos, status de anemia e medicamentos entre os grupos FRE e não-FRE. Posteriormente, realizamos uma análise multivariada. Também avaliamos desfechos, como DCE em um ano e óbito em dez anos. Resultados: Observamos menor frequência de concentração de hemoglobina (Hb) pré-transplante, mas maior frequência de creatinina sérica do doador e transfusão de hemácias no período de uma semana após o transplante no grupo FRE. Além disso, houve associação independente entre a concentração de Hb antes do transplante e a FRE [OR 0,252; IC 95%: 0,159-0,401; p < 0,001]. Houve também associação entre a concentração de Hb após seis meses de transplante renal e ambos, DCE [OR 0,798; IC95%: 0,687-0,926; p = 0,003] e óbito por qualquer causa. Conclusão: Encontrou-se uma associação entre anemia pré-transplante e FRE e entre anemia seis meses após o transplante e ambos, DCE e óbito por qualquer causa. Assim, a anemia antes ou após o transplante afeta os desfechos de pacientes que foram submetidos a transplante renal de doador falecido.

Pelvic radiation therapy with volumetric modulated arc therapy and intensity-modulated radiotherapy after renal transplant: A report of 3 cases.

AIM: Describe characteristics and outcomes of three patients treated with pelvic radiation therapy after kidney transplant. BACKGROUND: The incidence of pelvic cancers in kidney transplant (KT) recipients is rising. Currently it is the leading cause of death. Moreover, treatment is challenging because anatomical variants, comorbidities, and associated treatments, which raises the concern of using radiotherapy (RT). RT has been discouraged due to the increased risk of urethral/ureteral stricture and KT dysfunction. MATERIALS AND METHODS: We reviewed the electronic health records and digital planning system of patients treated with pelvic RT between December 2013 and December 2018 to identify patients with previous KT. CASES DESCRIPTION: We describe three successful cases of KT patients in which modern techniques allowed full standard RT for pelvic malignances (2 prostate and 1 vaginal cancer) with or without elective pelvic nodal RT, without allograft toxicity at short and long follow-up (up to 60 months). CONCLUSION: When needed, RT modern techniques remain a valid option with excellent oncologic results and acceptable toxicity. Physicians should give special considerations to accomplish all OAR dose constraints in the patient's specific setting. Recent publications recommend KT mean dose <4 Gy, but graft proximity to CTV makes this unfeasible. We present 2 cases where dose constraint was not achieved, and to a short follow-up of 20 months renal toxicity has not been documented. We recommend the lowest possible mean dose to the KT, but never compromising the CTV coverage, since morbimortality from recurrent or progressive cancer disease outweighs the risk of graft injury.

Ureterocalicostomy with lower pole nephrectomy in a renal transplant: A case report.

As the number of kidney transplants continues to rise, so does the number and complexities of surgical-related complications, which may be associated with increased morbidity and potentially graft loss. Ureteral stenosis, the most prevalent urological complication, may require diverse techniques for surgical correction depending on several recipient and graft abnormalities. Here we report the surgical and clinical outcomes of a 62-year-old man with a posttransplant pyeloureterostomy stricture successfully treated with ureterocalicostomy after a lower pole nephrectomy. Although the resection of renal parenchyma may prevent a stenosis recurrence, surgeons can be reluctant to use this strategy due to the possible negative impact on renal function. We highlight some key steps of the surgical technique to prevent unnecessary allograft lesion and present short-term outcomes, suggesting that this rarely described procedure is a safe and effective alternative treatment for kidney transplant recipients with pyeloureterostomy stenosis.

Impact of machine perfusion after long static cold storage on delayed graft function incidence and duration and time to hospital discharge.

Delayed graft function (DGF) is very high in our center (70%-80%), and we usually receive a kidney for transplant after more than 22 hours of static cold ischemia time (CIT). Also, there is an inadequate care of the donors, contributing to a high rate of DGF. We decided to test whether machine perfusion (MP) after a CIT improved the outcome of our transplant patients. We analyzed the incidence of DGF, its duration, and the length of hospital stay (LOS) in patients who received a kidney preserved with MP after a CIT (hybrid perfusion-HP). We included 54 deceased donors kidneys preserved with HP transplanted from Feb/13 to Jul/14, and compared them to 101 kidney transplants preserved by static cold storage (CS) from Nov/08 to May/12. The median pumping time was 11 hours. DGF incidence was 61.1% vs 79.2% (P = .02), median DGF duration was 5 vs 11 days (P < .001), and median LOS was 13 vs 18 days (P < .011), for the HP compared to CS group. The observed reduction of DGF with machine perfusion did not occur in donors over 50 years old. In the multivariate analysis, risk factors for DGF, adjusted for CIT, were donor age (OR, 1.04; P = .005) and the absence of use of MP (OR, 1.54; P = .051). In conclusion, the use of HP contributed to faster recovery of renal function and to a shorter length of hospital stay.

Glomerulopatí del trasplante. Resultados clínicos y seguimiento de casos.

OBJECTIVE: We describe the evolution of graft function in patients with transplant glomerulopathy measure by levels of serum creatinine, proteinuria and estimated glomerular filtration rate. METHOD: Cross-sectional study conducted in the Regional General Hospital No. 46 IMSS. Included patients with kidney allograft and diagnosis of renal biopsy of transplant glomerulopathy grafting between January 1, 2006 to April 31, 2013 serum creatinine, proteinuria and estimated glomerular filtration rate at diagnosis, 6, 12 and 24 was recorded months. The results are shown with numbers, percentages and standard deviations. RESULTS: 42 patients were included. At 6 months of diagnosis, 14% decline in graft function and 7.1% graft loss. At 12 months, 17.9% graft loss, and at 24 months 36.3% had chronic graft dysfunction and graft loss as return to dialysis. CONCLUSIONS: Evolution in our patients seems to be better to other series of cases reported in the literature.

Clinical Significance of Pretransplant Donor-Specific Antibodies in the Setting of Negative Cell-Based Flow Cytometry Crossmatching in Kidney Transplant Recipients.

Antibodies to donor-specific HLA antigens (donor-specific antibodies [DSA]) detected by single-antigen bead (SAB) analysis prior to kidney transplant have been associated with inferior graft outcomes. However, studies of pretransplant DSA, specifically in the setting of a negative flow cytometry crossmatch (FCXM) without desensitization therapy, are limited. Six hundred and sixty kidney and kidney-pancreas recipients with a negative pretransplant FCXM from September 2007 to August 2012 without desensitization therapy were analyzed with a median follow-up of 4.2 years. All patients underwent cell-based FCXM and SAB analysis on current and historic sera prior to transplantation. One hundred and sixty-two patients (24.5%) had DSA detected prior to transplant. One-year acute rejection rates were similar in DSA-positive versus DSA-negative patients (15.4% vs. 11.4%, respectively; p = 0.18) and were higher in those with DSA mean fluorescence intensity (MFI) greater than or equal to 3000 in multivariable analysis (p = 0.046). The estimated glomerular filtration rate (eGFR) at 3 and 4 years was lower in the DSA(+) versus the DSA(-) group (p = 0.050 at 3 years) without an impact on 5-year death-censored graft survival (89.0% vs. 90.6%, respectively; p = 0.53). Timing (current or historic) of DSA detection did not alter these findings. In conclusion, pretransplant DSA in the setting of a negative FCXM confers minimal immunologic risk in the intermediate term, does not necessitate desensitization therapy and should not represent a barrier to renal transplant.

Donor Hemodynamics as a Predictor of Outcomes After Kidney Transplantation From Donors After Cardiac Death.

Donation after cardiac death is an important source of transplantable organs, but evidence suggests donor warm ischemia contributes to inferior outcomes. Attempts to predict recipient outcome using donor hemodynamic measurements have not yielded statistically significant results. We evaluated novel measures of donor hemodynamics as predictors of delayed graft function and graft failure in a cohort of 1050 kidneys from 566 donors. Hemodynamics were described using regression line slopes, areas under the curve, and time beyond thresholds for systolic blood pressure, oxygen saturation, and shock index (heart rate divided by systolic blood pressure). A logistic generalized estimation equation model showed that area under the curve for systolic blood pressure was predictive of delayed graft function (above median: odds ratio 1.42, 95% confidence interval [CI] 1.06-1.90). Multivariable Cox regression demonstrated that slope of oxygen saturation during the first 10 minutes after extubation was associated with graft failure (below median: hazard ratio 1.30, 95% CI 1.03-1.64), with 5-year graft survival of 70.0% (95%CI 64.5%-74.8%) for donors above the median versus 61.4% (95%CI 55.5%-66.7%) for those below the median. Among older donors, increased shock index slope was associated with increased hazard of graft failure. Validation of these findings is necessary to determine the utility of characterizing donor warm ischemia to predict recipient outcome.

Increased urinary cystatin C level is associated with interstitial fibrosis and tubular atrophy in kidney allograft recipients.

AIM: The objective of this study was to investigate the correlation between the urinary excretion of cystatin C (CysC) and the presence of interstitial fibrosis/tubular atrophy (IF/TA) in renal transplant (RT) recipients. METHODS: This prospective study included 21 adult patients who had undergone renal biopsy and RT ≥6 months prior. According to the renal biopsy reports, the patients were divided into groups with (n=12) or without (n=9) IF/TA. Analytical parameters included the following: serum and urinary levels of CysC, creatinine (Cr) and sodium (Na), total urinary protein, urinary CysC/creatinine ratio [u(CysC/Cr)], fractional excretion of sodium (FENa) and estimated glomerular filtration rate (eGFR) based on the Chronic Kidney Disease Epidemiology Collaboration equation. RESULTS: The values of uCysC, u(CysC/Cr), proteinuria, and FENa were significantly higher in patients with IF/TA than in patients without IF/TA. The values of eGFR were statistically lower in patients with IF/TA (p=0.001). Values of uCysC significantly correlated with those of serum Cr, FENa, and eGFR (p<0.001). Among the patients with IF/TA, 67% presented with glomerulosclerosis (segmental/global). CONCLUSION: Elevated levels of urinary CysC are associated with interstitial fibrosis and tubular atrophy in RT recipients and may become a useful tool for monitoring kidney allografts.

Glucocorticoid resistance in dialysis patients reduces long-term graft survival after kidney transplantation.

Glucocorticoid (GC) resistance has been observed in chronic kidney disease (CKD) patients on dialysis. It can be evaluated by binding assays based on the dissociation constant (Kd), which is inversely proportional to ligand affinity. CKD patients with GC resistance had increased number of acute rejection episodes. We followed up 26 patients that underwent kidney transplantation to observe whether GC resistance could affect the response to acute rejection episode pulse therapy and the long-term allograft outcome. Using Kaplan-Meier survival curve, GC resistant patients showed lower acute rejection-free survival (p=0.03) and lower kidney allograft survival (p=0.008). No difference was found regarding number of deaths. Multivariate logistic regression showed that high Kd value was an independent predictor of lower kidney allograft survival (p=0.001). There was a negative Spearman correlation between Kd and kidney allograft survival (r=-0.88, p=0.03). In conclusion, our findings indicate the usefulness of binding assay performed previously to kidney transplantation to define GC resistance. In addition, the dissociation constant (Kd) is a reliable and independent predictive marker of higher frequency of acute rejection episodes, lower rejection-free graft survival, poor response of acute rejection episodes to methylprednisolone pulse therapy, and lower kidney allograft survival in a long-term follow-up.