Assessing Health-Related Quality of Life in Non-Directed Versus Directed Kidney Donors: Implications for the Promotion of Non-Directed Donation.

Living kidney donation has increased significantly, but little is known about the post-donation health-related quality of life (HRQoL) of non-directed donors (NDs) vs. directed donors (DDs). We thus examined the outcomes of 112 living kidney donors (82 NDs, 30 DDs). For the primary outcomes-namely, the mean physical component summary (PCS) and mental component summary (MCS) scores of the 12-item Short Form Survey (SF-12) questionnaire-scores were significantly higher for the NDs vs. the DDs (PCS: +2.69, MCS: +4.43). For secondary outcomes, NDs had shorter hospital stays (3.4 vs. 4.4 days), returned to physical activity earlier (45 vs. 60 days), exercised more before and after donation, and continued physical activity post-donation. Regression analyses revealed that donor type and white blood cell count were predictive of the PCS-12 score, and donor type was predictive of the MCS-12 score. Non-directed donation was predictive of a shorter hospital stay (by 0.78 days, p < 0.001) and the odds of having PCS-12 and MCS-12 scores above 50 were almost 10 and 16 times higher for NDs, respectively (p < 0.05). These findings indicate the safety and potential benefits of promoting non-directed donation. However, careful selection processes must be maintained to prevent harm and exploitation.

Predictors and Adverse Outcomes of Acute Kidney Injury in Hospitalized Renal Transplant Recipients.

Data about in-hospital AKI in RTRs is lacking. We conducted a retrospective study of 292 RTRs, with 807 hospital admissions, to reveal predictors and outcomes of AKI during admission. In-hospital AKI developed in 149 patients (51%). AKI in a previous admission was associated with a more than twofold increased risk of AKI in subsequent admissions (OR 2.13, p < 0.001). Other major significant predictors for in-hospital AKI included an infection as the major admission diagnosis (OR 2.93, p = 0.015), a medical history of hypertension (OR 1.91, p = 0.027), minimum systolic blood pressure (OR 0.98, p = 0.002), maximum tacrolimus trough level (OR 1.08, p = 0.005), hemoglobin level (OR 0.9, p = 0.016) and albumin level (OR 0.51, p = 0.025) during admission. Compared to admissions with no AKI, admissions with AKI were associated with longer length of stay (median time of 3.83 vs. 7.01 days, p < 0.001). In-hospital AKI was associated with higher rates of mortality during admission, almost doubled odds for rehospitalization within 90 days from discharge and increased the risk of overall mortality in multivariable mixed effect models. In-hospital AKI is common and is associated with poor short- and long-term outcomes. Strategies to prevent AKI during admission in RTRs should be implemented to reduce re-admission rates and improve patient survival.

The Clinical Manifestation of Immunosuppressive Therapy as a Tool to Improve Immune Monitoring in Renal Transplant Recipients.

INTRODUCTION: Metrics for posttransplant immune monitoring to prevent over or under immunosuppression in renal transplant recipients (RTRs) are lacking. METHODS: We surveyed 132 RTRs, 38 in the first year posttransplant and 94 >1-year posttransplant, to study the clinical expression of immunosuppressive therapy. A questionnaire administered to these RTRs was divided into physical (Q physical) and mental (Q mental) symptoms. RESULTS: In multivariable models for the association between the calculated Q physical and Q mental scores and different clinical and biochemical variables in the 38 RTRs who filled out the questionnaire 130 times during the first year posttransplant, it was found that mycophenolic acid (MPA) and prednisone use increased the mean Q physical score by 0.59 (95% CI: 0.21-0.98, p = 0.002) and 0.53 (95% CI: 0.26-0.81, p = 0.00), respectively, while MPA use increased the mean Q mental score by 0.72 (95% CI: 0.31-1.12, p = 0.001). Among the 94 RTRs who each completed the questionnaire only once, the odds for the mean Q mental score to be above the median value were more than 3 times higher for RTRs treated versus non-treated with MPA (OR 3.38, 95% CI: 1.1-10.3, p = 0.03). MPA-treated RTRs had higher mean scores for questions related to sleep disorders (1.83 ± 1.06 vs. 1.32 ± 0.67 for not treated, p = 0.037), to difficulty falling asleep (1.72 ± 1.11 vs. 1.16 ± 0.5, p = 0.02), and to depression and anxiety. CONCLUSION: We concluded that prednisone and MPA use are associated with an increased Q physical and Q mental scores in RTRs. Routine monitoring of physical and mental status of RTRs should be implemented to improve the diagnosis of overimmunosuppression. Dose reduction or discontinuation of MPA should be considered in RTRs who report sleep disorders, depression, and anxiety.

[ORGAN TRANSPLANT HISTORY IN ISRAEL].

INTRODUCTION: Organ transplantation is an innovative field that was pioneered in the middle of the last century with the development of surgical techniques, advances in the understanding of immunological processes that cause rejection, introduction of drugs to prevent rejection and improved methods for organ preservation. In Israel, the first heart transplantation and kidney transplantation were performed in the mid-1960's followed by pancreas, lung and liver transplantation that were conducted for the first time in the late 1980's and early 1990's. The significant change that has led to an increase in the number of transplants in Israel and rising success rates after transplant has occurred with the introduction of the new generation of anti-rejection drugs, Cyclosporine and subsequently Tacrolimus (Prograf ®). Another milestone was the founding of The National Transplant Center in 1994. This led to the formation of national transplant candidate lists for each organ, the establishment of professional committees that determine organ allocation policy and the creation of a governmental ethics committee to oversee the performance of live-donor transplantation. In 2008, about a month before the signing of the Istanbul Declaration, the Transplantation Law was enacted to regulate organ transplantation in Israel, which included clauses restricting organ trade in the spirit of the Istanbul Declaration. These measures increased the number of transplants performed in Israel and significantly reduced the number of transplants of Israelis abroad. The establishment of Matanat Chaim Organization in 2012 is another milestone that has led to a significant increase in the number of kidney transplants, most of which are currently performed from altruistic donations. However, today there is still a shortage of organs for transplantation from deceased donors and there is a long way to go to close the gap between organ need and supply. This review will indicate the introduction of the first transplants performed in Israel and the measures undertaken to increase the number of transplants. In addition, the review will note the laws and regulations of organ allocation.

BNT162b2 Third Booster Dose Significantly Increases the Humoral Response Assessed by Both RBD IgG and Neutralizing Antibodies in Renal Transplant Recipients.

Background: An impaired humoral response to full dose of BNT162b2 vaccine was observed in renal transplant recipients (RTR). Methods: To reveal predictors for humoral response to third vaccine, patients were stratified to positive (N = 85) and negative (N = 14) response groups based on receptor-binding domain (RBD) IgG ≥1.1 and neutralizing antibodies (NA) ≥ 16 dilution versus RBD IgG <1.1 or NA < 16, respectively. NA were detected using a SARS-CoV-2 pseudo-virus. Results: Response rate increased from 32.3% (32/99) before the third dose to 85.9% (85/99) post-third vaccine with a significant rise in geometric mean titers (GMTs) for RBD IgG and NA [0.79 (95% CI 0.65-0.96) vs. 3.08 (95% CI 2.76-3.45), p < 0.001 and 17.46 (95% CI 12.38-24.62) vs. 362.2 (95% CI 220.7-594.6), p < 0.001 respective. 80.6% (54/67) seroconverted and 96.9% (31/32) remained positive following the vaccine with a significant increase in GMTs for RBD IgG and NA. Age, ESRD secondary to diabetic nephropathy (DN) and renal allograft function were independent predictors for antibody response in RTR. Mycophenolic acid (MPA) use and dose had no impact on humoral response following the third booster. AEs were recorded for 70.1% of RTR population. Systemic AEs were more common in recipients with a positive humoral response as opposed to non-responders (45.2% versus 15.4% respectively, p = 0.04). Conclusion: 85.9% of RTR develop NA to BNT162b2 third vaccine, found effective in both negative and positive responders prior to the vaccine. Antigenic re-exposure overcame the suppressive effect of MPA on antibody response in RTR.

A multidisciplinary nephrogenetic referral clinic for children and adults-diagnostic achievements and insights.

BACKGROUND: Genetic kidney diseases contribute a significant portion of kidney diseases in children and young adults. Nephrogenetics is a rapidly evolving subspecialty; however, in the clinical setting, increased use of genetic testing poses implementation challenges. Consequently, we established a national nephrogenetics clinic to apply a multidisciplinary model. METHODS: Patients were referred from different pediatric or adult nephrology units across the country if their primary nephrologist suspected an undiagnosed genetic kidney disease. We determined the diagnostic rate and observed the effect of diagnosis on medical care. We also discuss the requirements of a nephrogenetics clinic in terms of logistics, recommended indications for referral, and building a multidisciplinary team. RESULTS: Over 24 months, genetic evaluation was completed for a total of 74 unrelated probands, with an age range of 10 days to 72 years. The most common phenotypes included congenital anomalies of the kidneys and urinary tract, nephrotic syndrome or unexplained proteinuria, nephrocalcinosis/nephrolithiasis, tubulopathies, and unexplained kidney failure. Over 80% of patients were referred due to clinical suspicion of an undetermined underlying genetic diagnosis. A molecular diagnosis was reached in 42/74 probands, yielding a diagnostic rate of 57%. Of these, over 71% of diagnoses were made via next generation sequencing (gene panel or exome sequencing). CONCLUSIONS: We identified a substantial fraction of genetic kidney etiologies among previously undiagnosed individuals which influenced subsequent clinical management. Our results support that nephrogenetics, a rapidly evolving field, may benefit from well-defined multidisciplinary co-management administered by a designated team of nephrologist, geneticist, and bioinformatician. A higher resolution version of the Graphical abstract is available as Supplementary information.

Long-term outcomes of Roux-en-Y gastric bypass or sleeve gastrectomy in patients with cirrhosis; before, during or after liver transplantation: A single center's experience.

BACKGROUND: The increasing prevalence of morbid obesity (MO) results in parallel growth of obesity-associated liver diseases necessitating liver transplantation (LT). OBJECTIVE: To examine the feasibility and safety of Roux-en-Y gastric bypass or sleeve gastrectomy in the setting of LT. METHODS: This retrospective chart review included the data on all the MO candidates before and after LT who underwent bariatric surgery (BS) in our institution between 04/2013-09/2016. The reported outcomes were weight change and early and late postoperative complications (mean follow-up: 43 ± 11.1 months). RESULTS: Eighteen MO peri-LT patients (10 females, 8 males, average age 48 years) were included in the study. Ten had cirrhosis (mean Model of End-stage Liver Disease [MELD] score of 12.5 ± 6.42), three underwent concurrent LT and BS (mean MELD score 23.7 ± 0.58), and five had LT (mean of 56 months from LT). The mean percentage of total and excess weight loss was 31% and 81%, respectively. Six of the eight patients with type 2 diabetes mellitus became normoglycemic after BS. Three patients sustained perioperative complications. Two cirrhotic patients died 1 and 4.5 years after BS with decompensation. CONCLUSIONS: Bariatric surgery appears to effectively address obesity in cirrhotic and LT patients. The surgical risk is higher than that of the regular BS population.

Short versus prolonged antibiotic treatment for complicated urinary tract infection after kidney transplantation.

There is no consensus regarding the optimal duration of antibiotic therapy for urinary tract infection (UTI) following kidney transplantation (KT). We performed a retrospective study comparing short (6-10 days) versus prolonged (11-21 days) antibiotic therapy for complicated UTI among KT recipients. Univariate and inverse probability treatment weighted (IPTW) adjusted multivariate analysis for composite primary outcome of all-cause mortality or readmissions within 30 days and relapsed UTI 180 days were performed. Overall, 214 KT recipients with complicated UTI were included; 115 short-course treatment (median 8, interquartile range [IQR] 6-9 days), 99 prolonged course (median 14, IQR 12-21 days). The composite outcome occurred in 33 (28.6%) in the short-course group and 30 (30%) in the prolonged-course group; relapsed UTI occurred in 19 (16.5%) vs. 21 (21%), respectively. Duration of antibiotic treatment was not associated with any of these outcomes. The only risk factor for mortality/readmissions in multivariate analysis was deceased donor. No differences between groups were demonstrated for length of hospital stay, rates of bacteraemia, resistance development, and serum creatinine at 30 and 90 days. In conclusion, we found no difference in clinical outcomes between KT recipients treated for complicated UTI with short-course antibiotic (6-10 days) versus longer course (11-21 days).

Long-term outcomes during 37 years of pediatric kidney transplantation: a cohort study comparing ethnic groups.

BACKGROUND: This study aimed to evaluate short- and long-term outcomes of kidney transplantation over 37 years in a national referral center and compare outcomes between Israeli Jewish and Arab children. METHODS: Data on 599 pediatric transplantations performed in 545 children during 1981-2017, including demographic parameters, kidney failure disease profile, and pre-transplant dialysis duration, were retrieved from our computerized database and patient files. Patient and graft survival were estimated using the Kaplan-Meier method. RESULTS: Twenty-year patient survival was 91.4% for live donor (LD) and 80.2% for deceased donor (DD) kidney recipients. Respective 10-year and 20-year graft survival rates for first kidney-only transplants were 75.2% and 47.0% for LD and 60.7% and 38.4% for DD grafts. Long-term graft survival improved significantly (p < 0.001) over the study period for recipients of both LD and DD allografts and reached 7-year graft survival of 92.0% and 71.3%, respectively. The proportion of DD transplantations was higher in the Arab subpopulation: 73.8% vs. 48.4% (p < 0.001). Graft survival was not associated with age at transplantation and did not differ between the Arab (N = 202) and Jewish children (N = 343). Median (IQR) waiting time on dialysis did not differ significantly between the Arab and Jewish children: 18 (10-30) and 15 (9-30) months, respectively (p Mann-Whitney = 0.312). CONCLUSIONS: Good and progressively improving long-term results were obtained in pediatric kidney transplantation at our national referral center, apparently due to expertise gained over time and advances in immunosuppression. Equal access to DD kidney transplant and similar graft survival were found between ethnic groups.

Can uric acid blood levels in renal transplant recipients predict allograft outcome?

BACKGROUND: Hyperuricemia is common after renal transplantation, especially in those receiving calcineurin inhibitors. Little, however, is known about the relationship between uric acid (UA) levels and allograft outcome. METHODS: We conducted a retrospective single-center analysis (N = 368) in order to assess UA blood levels post-transplant association with allograft outcome. For this study, a median serum UA level of all measured UA levels from 1 month to 1 year post renal transplantation was calculated. RESULTS: Patients were divided into 2 groups based on the median UA level measured between 1 and 12 months post-transplant. Those with median UA level ≥ 7 and ≥ 6 mg/dL (N = 164) versus median UA level < 7 and < 6 mg/dL for men and women respectively (N = 204) had lower GFR values at 1, 3 and 5 years posttransplant (mean GFR ± SD of 43.4 ± 20.6 and 58 ± 19.9 at 3 years post-transplant, p < 0.001). In multivariate models, UA levels were no longer significantly associated with renal allograft function. In a multivariate cox proportional hazard model, UA level was found to be independently associated with increased risk for death-censored graft loss (HR of 1.3, 95% CI 1.0-1.7, p < 0.05 for every increase of 1 mg/dL in UA level). CONCLUSION: Hyperuricemia was found to be associated with increased death- censored graft loss but not with allograft function. Increased UA levels were not found to be an independent predictor of long-term allograft function despite the known association of hyperuricemia with the progression of cardiovascular and renal disease.

Early persistent hyperparathyroidism post-renal transplantation as a predictor of worse graft function and mortality after transplantation.

BACKGROUND: Persistent hyperparathyroidism (pHPT) is frequently seen after transplantation contributing to post-transplant complications. METHODS: We conducted a retrospective single center analysis to explore the relationship of early pHPT and long-term allograft outcome. Patients were divided into high (N = 153) and low (N = 252) PTH groups based on serum parathyroid hormone (PTH) level 3 months post-transplant (PTH ≥ 150 and < 150 pg/mL, respectively). RESULTS: High PTH was found to be an independent predictor for reduced kidney allograft function up to 3 years post-transplant. eGFR decreased by 11.4 mL/min (P < .001) and the odds of having an eGFR < 60 mL/min 3 years post-transplant were sixfold higher (P < .01) in the high compared to the low PTH group. Subgroup analysis based on eGFR 1 year post-transplant, presence of slow graft function (SGF), and transplant type revealed similar results. High PTH three months post-transplant was also independently associated with an increased risk for overall mortality and for death with a functioning graft (P < .05). CONCLUSIONS: pHPT three months post-renal transplantation is an independent predictor for a worse allograft function up to 3 years post-transplant and a risk factor for mortality. This relationship remains statistically significant after accounting for baseline allograft function, presence of SGF and serum mineral levels abnormalities.

Post-Liver Transplantation Anemia and Its Correlation with Mortality and Graft Failure.

BACKGROUND: In adults, post-liver transplantation anemia (PLTA) is common, but its characteristics and long-term influence on major outcomes have yet to be elucidated. AIM: We aimed to assess prevalence, characteristics, predictors, and outcomes of PLTA at 6 months (early PLTA) and at 2 years (late PLTA). METHODS: A single-center retrospective cohort study using prospectively collected data from liver transplantations in adults during January 2007-December 2015. PLTA impact on various long-term outcomes was assessed, including mortality, composites of mortality or graft failure, cardiovascular outcomes, and malignancy occurrences. RESULTS: Hundred and fifty liver transplanted individuals were included. There was a 79% prevalence of anemia pre-transplantation, whereas early and late PLTA were evident in 58% and 40% of patients, respectively. Pre-transplantation anemia was associated with development of early PLTA which was associated with late PLTA. In a multivariate analysis, early PLTA was significantly associated with mortality or graft failure at a follow-up of 3 years (odds ratio 3.838, 95% CI 1.114-13.226). Late PLTA was not significantly associated with worse long-term outcomes. CONCLUSIONS: Early and late PLTA are prevalent among liver transplanted patients. Early PLTA is associated with long-term mortality or graft failure.

Flow-controlled fluoroscopic angiography for the assessment of vascular integrity in bioengineered kidneys.

Perfusion decellularization has been proposed as a promising method for generating nonimmunogenic organs from allogeneic or xenogeneic donors. Several imaging modalities have been used to assess vascular integrity in bioengineered organs with no consistency in the methodology used. Here, we studied the use of fluoroscopic angiography performed under controlled flow conditions for vascular integrity assessment in bioengineered kidneys. Porcine kidneys underwent ex vivo angiography before and after perfusion decellularization. Arterial and venous patencies were defined as visualization of contrast medium (CM) in distal capillaries and renal vein, respectively. Changes in vascular permeability were visualized and quantified. No differences in patency were detected in decellularized kidneys compared with native kidneys. However, focal parenchymal opacities and significant delay in CM clearance were detected in decellularized kidneys, indicating increased permeability. Biopsy-induced leakage was visualized in both groups, with digital subtraction angiography revealing minimal CM leakage earlier than nonsubtracted fluoroscopy. In summary, quantitative assessment of vascular permeability should be coupled with patency when studying the effect of perfusion decellularization on kidney vasculature. Flow-controlled angiography should be considered as the method of choice for vascular assessment in bioengineered kidneys. Adopting this methodology for organs premodified ex vivo under normothermic machine perfusion settings is also suggested.

The Wnt/ß-catenin pathway determines the predisposition and efficiency of liver-to-pancreas reprogramming.

Transdifferentiation (TD) is the direct reprogramming of adult cells into cells of alternate fate and function. We have previously shown that liver cells can be transdifferentiated into beta-like, insulin-producing cells through ectopic expression of pancreatic transcription factors (pTFs). However, the efficiency of the process was consistently limited to <15% of the human liver cells treated in culture. The data in the current study suggest that liver-to-pancreas TD is restricted to a specific population of liver cells that is predisposed to undergo reprogramming. We isolated TD-predisposed subpopulation of liver cells from >15 human donors using a lineage tracing system based on the Wnt response element, part of the pericentral-specific promoter of glutamine synthetase. The cells, that were propagated separately, consistently exhibited efficient fate switch and insulin production and secretion in >60% of the cells upon pTF expression. The rest of the cells, which originated from 85% of the culture, resisted TD. Both populations expressed the ectopic pTFs with similar efficiencies, followed by similar repression of hepatic genes. Our data suggest that the TD-predisposed cells originate from a distinct population of liver cells that are enriched for Wnt signaling, which is obligatory for efficient TD. In TD-resistant populations, Wnt induction is insufficient to induce TD. An additional step of chromatin opening enables TD of these cells. CONCLUSION: Liver-to-pancreas TD occurs in defined predisposed cells. These cells' predisposition is maintained by Wnt signaling that endows the cells with the plasticity needed to alter their transcriptional program and developmental fate when triggered by ectopic pTFs. These results may have clinical implications by drastically increasing the efficacy of TD in future clinical uses. (Hepatology 2018).

Immunosuppression reduction in kidney transplant recipients during bacterial infection-A retrospective study.

BACKGROUND: Immunosuppression reduction is a common practice in the management of bacterial infection among kidney transplant recipients (KTRs). This practice, however, is based on limited evidence. METHODS: Retrospective study comparing clinical outcomes of KTRs whose antimetabolite was discontinued vs continued during hospitalization due to bacterial infection, considering calcineurin inhibitors (CNI) levels. Primary outcome was a composite of clinical failure at day 5; all-cause mortality; and/or re-hospitalization at 90 days. Multivariable analysis of risk factors for the primary outcome was performed using a propensity-matched cohort. RESULTS: We included 183 KTRs hospitalized with bacterial infection. Neither discontinuation of antimetabolites nor lower levels of CNI at infection onset were associated with a significant decrease the composite primary outcome. No significant difference in graft loss or rejection was demonstrated between patients with low vs high CNI levels or discontinuation vs continuation of antimetabolite. In multivariable analysis, CNI levels and management of antimetabolite were not significantly associated with adverse outcome. CONCLUSIONS: Immunosuppression reduction in hospitalized KTRs with bacterial infection did not offer a clinical advantage in terms of mortality, re-hospitalization, or clinical success. An interventional study evaluating continuation of immunosuppression vs reduction should be considered.

Long-term results of desensitization protocol with and without rituximab in sensitized kidney transplant recipients.

BACKGROUND: Desensitization protocols have been developed in order to overcome the immunological barrier of donor-specific anti-HLA antibodies (DSA). METHODS: During 2006-2012, we implemented a program for desensitizing sensitized (positive DSA, negative NIH-CDC crossmatch) living-donor recipients. The long-term outcome of 36 sensitized recipients, treated with IVIG and plasmapheresis (PP), with or without rituximab (added when > 7500 MFI), was compared to 252 non-sensitized living-donor recipients. RESULTS: Median peak DSA level before desensitization was 7223 (range 3567-16 000) MFI. During a mean follow-up of 121.9 months, graft loss occurred in 6/36 (17%) of the sensitized and 15/251 (6%) of the non-sensitized recipients (P = 0.021). Five-year and 10-year death-censored graft survival rates were 85% and 81% compared to 95% and 92%, respectively, for the non-sensitized recipients. There was no difference in recipients' survival. Slightly more episodes of acute rejection occurred in the sensitized group but had not influence on graft survival. At the last follow-up, 28 recipients had functioning graft; seventeen (47%) did not have detectable DSA. Eleven recipients had excellent graft function despite having detectable DSA. CONCLUSION: The long-term outcomes of sensitized recipients who underwent desensitization are encouraging. Adding rituximab to PP + IVIG in candidates with very high titers may result in improved outcome.

Immunosuppression reduction in liver and kidney transplant recipients with suspected bacterial infection: A multinational survey.

BACKGROUND: There is no consensus on the optimal management of immunosuppression during bacterial infections among solid organ transplant recipients. METHODS: A multicenter, cross-sectional survey, of high-volume kidney and liver transplant centers across US and Europe. Structured questionnaires including six multiple-choice questions concerning the management of immunosuppression during infection were distributed among 381 centers. RESULTS: A total of 124 (33%) centers fully completed the questionnaire: 67 liver, 57 kidney centers. Participating centers reported heterogenous approaches to immunosuppression management for all types of immunosuppressive drugs. Notably, kidney centers reported similar frequencies of either discontinuation (19%), continuation (19%), or dose reduction (17.5%) of antimetabolites; discontinuation only for life-threatening infection (17.5%) or case by case decisions (27%). Calcineurin inhibitors (CNI) management was heterogenous mostly among liver centers, with 8% discontinuing the CNI, 18% continuing, and 22% reducing dose. Heterogenous approaches to management of steroids and inhibitors of the mammalian target of rapamycin were also demonstrated. CONCLUSIONS: Immunosuppression management during bacterial infection is heterogenous in US and European centers. Immunosupression reduction (ISR) during infection is a common practice, though supported by limited evidence. Demonstrating high heterogeneity in the approach to ISR, together with the equivocal results of clinical studies, support consideration of an interventional clinical trial.

Reduction of exposure to tacrolimus trough level variability is associated with better graft survival after kidney transplantation.

PURPOSE: High tacrolimus trough drug level variability was found to be associated with reduced graft survival. The primary goal of this study was to find whether reduction of exposure to high tacrolimus trough level variability in patients in which previously had high variability was associated with better graft survival. METHODS: All tacrolimus drug level values in patients that underwent kidney transplantation at our center between 2006 and 2015 were collected. Exposure to variability was calculated using a time-weighted coefficient of variability (TWCV). Time-dependent univariate and multivariate Cox proportional hazard models were used to analyze the primary outcome of graft survival and to determine a cutoff value for TWCV as a predictor of this outcome. RESULTS: A total of 878 patients were included in the study with a median follow-up of 1263 days. TWCV above 25% was significantly associated with reduced graft survival (HR3.66, 95% CI 2.3-5.8, p < 0.001). Of the 480 patients (54.7%) who had a cumulative TWCV of > 25% at a certain time during the follow-up, 110 (22.9%) later returned to a cumulative TWCV of less than 25%. Reduction of TWCV to values below 25% was associated with a hazard of graft loss that was not different from patients who had cumulative TWCV of less than 25% during the entire follow-up period (HR 1.81, 95% CI 0.71-4.62, p = 0.218 and HR 1.08, 95% CI 0.39-2.99, p = 0.780) in univariate and multivariate analyses, respectively. CONCLUSIONS: Monitoring TWCV can help detect the high-risk patients. Interventions intended to reduce variability on long-term graft survival may have a positive effect on graft survival.

Acute Kidney Injury and Long-Term Risk for Cardiovascular Events in Patients after Kidney Transplantation.

BACKGROUND: Acute kidney injury (AKI) was found to be associated with an increased risk of major adverse cardiovascular events (MACE) in the general population. Patients after kidney transplantation are prone to AKI events and are also at an increased risk of cardiovascular (CV) disease. The association between AKI and MACE in kidney transplant patients is yet to be studied. METHODS: This retrospective single-center cohort study reviewed 416 adult renal allograft recipients transplanted between 2005 and 2010. AKI events were recorded starting 2 weeks after transplantation, or following discharge with a functioning graft. AKI was defined, according to the KDIGO criteria. The primary outcome was the composite of MACE starting 6 months after transplantation and all-cause mortality. For survival analysis, we used univariate and multivariate time varying Cox proportional hazard model. RESULTS: One hundred and twenty-four patients (29.8%) had at least one episode of AKI. During the median follow-up time of 7.2 years (interquartile range 4.3-9.1), 144 outcome events occurred. By time varying Cox regression analysis, AKI was associated with an increased rate of CV outcomes or death (hazard ratio [HR] 1.96, 95% CI 1.36-2.81, p < 0.001), and the association remained significant by multivariate adjusted model (HR 1.76, 95% CI 1.18-2.63, p = 0.005). As for the different components of MACE, all-cause mortality and CV mortality were the only outcomes that were significantly associated with AKI. No interaction between AKI timing and MACE was found. CONCLUSION: AKI in kidney transplant recipient is associated with an increased risk of CV disease.