Growth Differentiation Factor 15 Is Superior to Troponin I in the Evaluation of Kidney Transplant Candidates.

INTRODUCTION: Pretransplant cardiac troponin I (cTNI) has demonstrated its predicting value in survival after kidney transplant. Growth differentiation factor 15 (GDF-15) is a biomarker currently studied as a predictor of mortality and cardiovascular events (CVE) in different scenarios. The aim of this study was to compare the utility of these two biomarkers in the prediction of events after kidney transplant. METHODS: We included 359 kidney transplants performed in our center between 2005 and 2015. cTNI and GDF-15 were measured on stored serum samples obtained pretransplant. RESULTS: Median GDF-15 was 5,346.4 pg/mL, and cTNI was 5.6 ng/L. After follow-up, 77 (21.5%) patients died, and the incidence of cerebrovascular accident (CVA), acute coronary syndrome (ACS), and major adverse CVEs (MACE) was 6.38%, 12.68%, and 20.56%, respectively. Patients were stratified in tertiles according to GDF-15 and cTNT levels. By multivariate cox regression analysis including both biomarkers and different clinical characteristics, we found a significant relation between GDF-15 and mortality, CVAs, and MACE (highest tertile hazard ratio [HR] 2.2 95% confidence interval [CI] [1.2-4.1], p = 0.01, HR 9.7 CI 95% [2.2-43.1], p = 0.003 and HR 2.7 CI 95% [1.4-5.1], p = 0.002). On the contrary, posttransplant ACS was related to cTNI (highest cTNI tertile HR 3.2 CI 95% [1.5-7.3], p = 0.003). DISCUSSION: Our study indicates the potential utility of GDF-15 as a mortality and CVE predictor after kidney transplant and its superiority compared to cTNI. By contrast, probably due to its tissue specificity, cardiac troponin showed a stronger correlation with acute coronary events. Although more studies are needed to confirm our findings, these two molecules could be used in conjunction with other tools to predict adverse events after transplant and ideally find strategies to minimize them.

Low-risk delisting strategy in highly sensitized patients without donor offers included in exchange donation programs. One single-center experience.

Donor exchange programs were designed to allocate organs for highly sensitized (HS) patients. The allocation algorithm differs slightly among countries and includes different strategies to improve access to transplants in HS patients. However, many HS patients with a calculated panel reactive of antibodies (cPRA) of 100 % remain on the waiting list for a long time. Some allocation algorithms assume immunological risk, including Imlifidase treatment, to increase the chance of transplantation in very HS patients. Here, we describe our unicenter experience of low-risk delisting strategy in 15 HS patients included in the Spanish donor exchange program without donor offers. After delisting, 7 out of 15 HS patients reduced the cPRA below 99.95 % and impacted the reduction of time on the waiting list (p = 0.01), where 5 out of 7 achieved transplantation. Within those HS that remained above 99.95 %, 1 out of 8 was transplanted. All the HS were transplanted with delisted DSA, and only one with DSA level rebounded early after transplantation. All HS transplanted after delisting maintain graft function. The transplant immunology laboratories are challenged to search intermediate risk assessment methods for delisting high HS patients.

Growth Differentiation Factor 15: A Biomarker with High Clinical Potential in the Evaluation of Kidney Transplant Candidates.

Kidney transplantation implies a significant improvement in patient survival. Nevertheless, early mortality after transplant remains high. Growth differentiation factor 15 (GDF-15) is a novel biomarker under study as a mortality predictor in multiple scenarios. The aim of this study is to assess the utility of GDF-15 to predict survival in kidney transplant candidates. For this purpose, 395 kidney transplant recipients with pretransplant stored serum samples were included. The median GDF-15 was 5331.3 (50.49-16242.3) pg/mL. After a mean of 90.6 ± 41.5 months of follow-up, 82 (20.8%) patients died. Patients with higher GDF-15 levels (high risk tertile) had a doubled risk of mortality after adjustment by clinical characteristics (p = 0.009). After adjustment by EPTS (Estimated Post Transplant Survival score) the association remained significant for medium hazards ratios (HR) 3.24 95%CI (1.2-8.8), p = 0.021 and high risk tertiles HR 4.3 95%CI (1.65-11.54), p = 0.003. GDF-15 improved the prognostic accuracy of EPTS at 1-year (ΔAUC = 0.09, p = 0.039) and 3-year mortality (ΔAUC = 0.11, p = 0.036). Our study suggests an independent association between higher GDF-15 levels and mortality after kidney transplant, adding accuracy to the EPTS score, an established risk prediction model currently used in kidney transplant candidates.

Immunosuppression with Calcineurin Inhibitor after Renal Transplant Failure Inhibits Allosensitization.

Immunosuppression withdrawal after graft failure seems to favor sensitization. A high percentage of calculated panel-reactive antibody (cPRA) and the development of de novo donor specific antibodies (dnDSA) indicate human leukocyte antigen (HLA) sensitization and may hinder the option of retransplantation. There are no established protocols on the immunosuppressive treatment that should be maintained after transplant failure. A retrospective analysis including 77 patients who lost their first renal graft between 1 January 2006-31 December 2015 was performed. Two sera were selected per patient, one immediately prior to graft loss and another one after graft failure. cPRA was calculated by Single Antigen in all patients. It was possible to analyze the development of dnDSA in 73 patients. By multivariate logistic regression analysis, the absence of calcineurin inhibitor (CNI) at 6 months after graft failure was related to cPRA > 75% (OR 4.8, CI 95% 1.5-15.0, p = 0.006). The absence of calcineurin inhibitor (CNI) at 6 months after graft loss was significantly associated with dnDSA development (OR 23.2, CI 95% 5.3-100.6, p < 0.001). Our results suggest that the absence of CNI at the sixth month after graft loss is a risk factor for sensitization. Therefore, maintenance of an immunosuppressive regimen based on CNI after transplant failure should be considered when a new transplant is planned, since it seems to prevent HLA allosensitization.

Is it possible to predict the evolution of IgAN? Validation of the IgA nephropathy progression calculator and its relationship with MEST-C score in our population. / ¿Es posible predecir la evolución de la nefropatia IgA? Validamos la calculadora de progresión de nefropatia IgA y su relación con Oxford score en nuestra población.

INTRODUCTION: IgA nephropathy (IgAN) is the most common and heterogeneous glomerular nephropathy. Several strategies have been used to determine the risk of progression to ESRD. We evaluate the prognostic significance and correlate the IgAN progression calculator (IgANPC) and the Oxford/MEST-C score in our population. MATERIAL AND METHODS: We performed a retrospective study of biopsied patients with diagnosis of IgA nephropathy from 1990 to 2015. We classified the biopsies using MEST-C score and we correlated the score to clinical evolution. We also calculated the risk of progression with the online IgANPC at the time of the biopsy. RESULTS: We analysed 48 biopsies, 83% of which were men with a mean age of 45 years at the time of the biopsy. Patients with a biopsy E1 according to MEST-C score had a higher IgANPC score than those with E0 (P=.021). The Pearson's correlation for the percentage of crescents and the IgANPC risk score was statistically significant (P=.014) with r=0.357. The percentage of patients with eGFR above 30 ml/min at 10 years was 100% for the low-risk group (group 1 of IgANPC), and 0% for the high-risk group (group 3), log rank P=0.001. The log rank comparison for variables of the MEST-C score, presented statistically significant results between E (0.036) and S (0.022) and the eGFR time<30 ml/min. A statistically significant relationship was also observed between T1 and eGFR<30 ml/min. The multivariate Cox regression analysis for IgANPC and eGFR<30 ml/min demonstrated a strong correlation (P=.016) between the risk group and eGFR <30 ml/min. CONCLUSION: In our study population, the IgANPC predicts the time to eGFR<30 ml/min, and adds information independent of the MEST. The MEST-C classification and IgANPC are useful and independent ÿolos for prognostic prediction, but more studies are needed to validate its use in the general population.