Metabolic Syndrome Is Related to Long-Term Graft Function in Renal Transplant Recipients

The metabolic syndrome (MS) is a known cardiovascular risk factor in the general population and a common problem among renal transplant recipients. This study investigated whether MS after renal transplantation affected long-term graft function.We included 112 transplants at our center between 2000 and 2002. We excluded patients with the presence of pretransplant diabetes or nonstable renal function at 1 year after transplantation. We evaluated parameters such as demographic features, medications, smoking history, body mass index, daily proteinuria, blood pressure, number of HLA mismatches, number of acute rejection episodes, delayed graft function, and laboratory parameters. Patients were followed for a mean of 69.86 ± 21.94 months. The prevalence of MS was determined using the National Cholesterol Education Program—Adult Treatment Panel III criteria.At 1 year after transplant, 28.6% of subjects had MS, whereas only 10.7% had MS before transplantation. Among 27.7% of patients graft failure had occurred during the follow-up; MS was more frequent among these individuals compared with those displaying stable renal function (51.6% vs 19.8%; P = .002). Older donor age, delayed graft function, acute rejection episodes, smoking history, MS, proteinuria, serum creatinine level, and C-reactive protein were associated with graft failure. Upon multivariate Cox regression analysis, patients with MS at 1 year after transplantation showed an increased risk for graft failure (relative risk, 0.22; 95% confidence interval, 0.06-0.75; P = .016). Older donor age and proteinuria level were other independent risk factors for graft failure.The MS was a prominent risk factor for graft failure. Because MS is a cluster of modifiable risk factors, early identification of patients at risk and intervention in due time may improve graft survival.     

460例次肾移植术后尿路并发症分析

本文报告我院460例次肾移植术后尿路并发症,共45例次,其中42例原发性(占9.13％),3例继发性,包括输尿管梗阻18例,输尿管或膀胱瘘26例,肾输尿管结石1例。除1例因行移植肾造瘘并发感染死亡外,余均经手术或非手术治愈。我们认为多数尿路并发症为外科技术所致,需要开放手术治疗。仔细的取肾、规范植肾手术操作和及早诊断是减少肾移植后尿路并发症发生的重要因素。     

Postoperative Voiding Dysfunction in Older Male Renal Transplant Recipients

Objective

To evaluate the incidence of voiding dysfunction in older male renal transplant recipients.

Patients and Methods

Data for 103 patients aged 60 years or older (mean age, 65.7 years; group 1) who underwent transplantation at our center between January 1999 and August 2007 were compared with data for a group of 139 younger patients (mean age, 50.1 years; group 2) treated within the same time frame.

Results

Postoperatively, 28 group 1 recipients (27%) and 26 group 2 recipients (19%) experienced voiding dysfunction after removal of the transurethral catheter (P = .12). The most common cause was bladder outlet obstruction due to benign prostatic hyperplasia in 26 patients in group 1 (25%) and 17 patients in group 2 (12%) (P = .009). Bladder neck contracture, urethral stricture, and detrusor underactivity were diagnosed in the other patients. Transurethral resection of the prostate gland was performed in 21 group 1 patients (20%) and 14 group 2 patients (10%) (P = .02) at a mean of 31.1 and 29.5 days, respectively (P = .23) after transplantation. Surgical procedures were performed without complication, and symptoms did not recur postoperatively.

Conclusions

Our data reveal a high incidence of voiding dysfunction in older male renal transplant recipients. High residual urine and urinary retention after renal transplantation may induce recurrent urinary tract infections, cause relevant complications, and seriously affect graft function. Recognizing the substantial effects of postoperative voiding dysfunction will enable optimum management of older kidney transplant recipients.     

Progression of Metabolic Syndrome in Renal Transplant Recipients

Background

Metabolic syndrome, which is closely related to insulin resistance, is highly prevalent in renal transplant recipients.

Purpose

We aimed to investigate prevalence, risk factors, and progression of metabolic syndrome in renal transplant recipients.

Methods

One hundred fifty-eight renal transplant recipients who had been on transplantation for more than 1 year and 79 age-sex matched healthy controls were included in the cross-sectional phase of the study. We measured baseline characteristics, blood pressure, fasting blood glucose, and lipid profiles and we defined metabolic syndrome using the National Cholesterol Education Program Adult Treatment Panel III criteria. One hundred twenty-four renal transplant recipients were eligible for the second evaluation after 22.9 ± 3.8 months. Metabolic syndrome prevalence and homeostasis model assessment insulin resistance levels were evaluated during the follow-up period.

Results

Overall, metabolic syndrome was present in 34.2% of the patients and 12.7% of the controls at the cross-sectional phase of the study (P = .000). Only the hypertension component of metabolic syndrome was significantly increased in patients compared to controls (P = .000). Pretransplantation weight and body mass index were significantly higher in patients who had metabolic syndrome (P = .000). During the follow-up period, prevalence of metabolic syndrome did not change (P = .510); however, body mass index and blood pressure increased and the high density lipoprotein cholesterol component of metabolic syndrome decreased (P = .001). We did not find any significant difference in glomerular filtration rate change among patients with and without metabolic syndrome (−2.2 ± 11.36 vs −6.14 ± 13.19; P = .091). Glucose metabolism parameters including hemoglobin A1c, insulin, and homeostasis model assessment insulin resistance were disturbed in patients with metabolic syndrome (P = .000, P = .001, P = .002, respectively).

Conclusion

Metabolic syndrome is highly prevalent in renal transplant recipients and closely associated with insulin resistance. The prominent criterion of metabolic syndrome in patients seems to be hypertension, especially high systolic blood pressure. The identification of metabolic syndrome as a risk factor may yield new treatment modalities to prevent it.     

HDL Cholesterol Efflux Predicts Graft Failure in Renal Transplant Recipients

High-density lipoprotein (HDL) particles are involved in the protection against cardiovascular disease by promoting cholesterol efflux, in which accumulated cholesterol is removed from macrophage foam cells. We investigated whether HDL cholesterol efflux capacity is associated with cardiovascular mortality, all-cause mortality, and graft failure in a cohort of renal transplant recipients (n=495, median follow-up 7.0 years). Cholesterol efflux capacity at baseline was quantified using incubation of human macrophage foam cells with apolipoprotein B–depleted plasma. Baseline efflux capacity was not different in deceased patients and survivors (P=0.60 or P=0.50 for cardiovascular or all-cause mortality, respectively), whereas recipients developing graft failure had lower efflux capacity than those with functioning grafts (P<0.001). Kaplan–Meier analysis demonstrated a lower risk for graft failure (P=0.004) but not cardiovascular (P=0.30) or all-cause mortality (P=0.31) with increasing gender-stratified tertiles of efflux capacity. Cox regression analyses adjusted for age and gender showed that efflux capacity was not associated with cardiovascular mortality (hazard ratio [HR], 0.89; 95% confidence interval [95% CI], 0.67 to 1.19; P=0.43). Furthermore, the association between efflux capacity and all-cause mortality (HR, .79; 95% CI, 0.63 to 0.98; P=0.031) disappeared after further adjustment for potential confounders. However, efflux capacity at baseline significantly predicted graft failure (HR, 0.43; 95% CI, 0.29 to 0.64; P<0.001) independent of apolipoprotein A-I, HDL cholesterol, or creatinine clearance. In conclusion, this prospective study shows that cholesterol efflux capacity from macrophage foam cells is not associated with cardiovascular or all-cause mortality but is a strong predictor of graft failure independent of plasma HDL cholesterol levels in renal transplant recipients.     

BKV in Simultaneous Pancreas-Kidney Transplant Recipients: A Leading Cause of Renal Graft Loss in First 2 Years Post-Transplant

With the introduction of more potent immunosuppressive agents, rejection has decreased in simultaneous pancreas/kidney transplant (SPK) recipients. However, as a consequence, opportunistic infections have increased. The purpose of this report is to outline the course of SPK patients who developed polyomavirus-associated nephropathy (PVAN). A retrospective review of 146 consecutive SPK recipients from January 1, 1996 to December 31, 2002 was performed. Immunosuppression, rejection and development of PVAN were reviewed. Nine patients were identified. All received induction with either OKT3 or thymoglobulin. Immunosuppression included tacrolimus/cyclosporine, MMF/azathioprine and sirolimus/prednisone. Two patients were treated for kidney rejection prior to the diagnosis of PVAN. Time to diagnosis was an average of 359.3 days post-transplantation. Immunosuppression was decreased but five ultimately lost function. However, none developed pancreatic abnormalities as demonstrated by normal glucose and amylase. Two underwent renal retransplantation after PVAN diagnosis and both have normal kidney function. PVAN was the leading cause of renal loss in SPK patients in the first 2 years after transplantation and is a serious concern for SPK recipients. The pancreas, however, is spared from evidence of infection, and no pancreatic rejection occurred when immunosuppression was decreased.     

Infective Complications Associated With Ureteral Stents in Renal Transplant Recipients

Objective

Stenting of the ureter is commonly performed during renal transplantation to avoid early complications. However, it predisposes to infections that may pose a significant threat to the graft and patient. Our study sought to investigate the incidence of infections associated with stents in renal transplant recipients.

Patients and Methods

A retrospective analysis of 100 consecutive renal transplant recipients performed over 1 year with 6 months follow-up.

Results

The median recipient age was 46 years (range, 19-71 years). Among the study group, 75 patients received an organ from deceased donor and 25 from live donor. In our study, there were 79 patients with a stent (ST) and 18 without a stent (WOST); 3 patients who required nephrectomy were excluded from the study. There were 2 ureteric stenoses that occurred following stent removal: 1 required surgical correction and 1 was treated radiologically. There were no cases of urinary leak. The incidence of urinary tract infection (UTI) was significantly greater among ST compared with WOST subjects (71% vs 39%; P = .02). New episodes of UTI following removal of the stent were more common among patients who had experienced infections while having a stent compared with infection-free stented patients (54% vs 30%; P = .04).

Conclusions

A ureteric stent may help to reduce early postoperative complications (leak and stricture), but increased the likelihood of UTI. Infection while having a ureteric stent was associated with a high recurrence rate of UTI even after stent removal.     

High Alternative Health Eating Index-Taiwan Scores Are Associated With Prevention of Graft Dysfunction in Taiwanese Renal Transplant Recipients

BackgroundVarious dietary quality indices demonstrate that a higher dietary quality score is associated with a reduced risk of several chronic diseases. However, creating an index tailored to the national population is crucial. The study investigated the association between the Alternative Healthy Eating Index-Taiwan (AHEI-Taiwan) and graft dysfunction in Taiwanese renal transplant recipients (RTRs).MethodsA prospective cohort study recruited 102 RTRs with a functioning allograft without acute rejection in the last 3 months from September 2016 to June 2018. Laboratory data were obtained from the medical records of patients. Graft dysfunction was indicated by an estimated glomerular filtration rate (eGFR) <60 mL/min per 1.73 m² in accordance with the Kidney Disease Outcomes Quality Initiative guideline. The dietary quality index AHEI-Taiwan was adapted from the AHEI based on Taiwanese dietary recommendations.ResultsMean age, renal transplant time, and eGFR were 48.9 ± 12.8 years, 8.5 ± 5.8 years, and 54.9 ± 17.8 mL/min per 1.73 m², respectively, in 102 RTRs. The RTRs with the highest quartile of AHEI-Taiwan scores were older and had a higher eGFR. Logistic regression analysis adjusted for age, sex, calories, Charlson comorbidity index, transplant time, and dialysis time showed that the highest quartile of the AHEI-Taiwan was associated with an 88% (odds ratio, 0.12; 95% CI, 0.03-0.59, P < .01) lower risk of graft dysfunction.ConclusionA high AHEI-Taiwan score was associated with a reduced risk of graft dysfunction in Taiwanese RTRs.     

Short-Term Prospective Study of Metabolic Syndrome in Renal Transplant Recipients

Background

Metabolic syndrome (MS) may affect patient and graft survival in renal transplant recipients. However, the evolution of MS during prospective follow-up remains uncertain.

Methods

Renal transplant patients were recruited for a study of MS in 2010 and then prospectively followed for 2 years. The modified Adult Treatment Panel III criteria adopted for Asian populations were used to define MS.

Results

A total of 302 cases (male:female = 154:148) with a mean duration of 10.5 ± 5.7 years after transplantation were enrolled. At initiation, 71 cases (23.5%) fulfilled the criteria of MS. At the end of follow-up, 11 cases had died and 21 had graft failure. Nine cases had insufficient data for reclassification. The remaining 261 cases completed a 2-year follow-up, and the prevalence of MS was 26.1% at the end of study. Of these, 7.79% (18 cases) of patients without MS had developed new-onset MS. Conversely, 16.9% (12 cases) with MS were free from MS at the end of study (P = .362). Patients with MS were associated with older age (57.1 ± 10.4 vs 52.6 ± 12.4 y; P = .006), more chronic allograft nephropathy (17.4% vs 7.1%; P = .01), proteinuria (22.5% vs 10.8%; P = .012), and use of more antihypertensive agents (1.49 ± 0.86 vs 0.80 ± 0.98; P < .0001). There was no significant change in serum creatinine in each subgroup.

Conclusions

The status of MS in renal transplant patients is dynamic. MS patients were associated with more chronic allograft nephropathy and proteinuria.     

Reticulated Platelets and Platelet Reactivity in Renal Transplant Recipients Receiving Antiplatelet Therapy

Introduction

Renal transplant recipients are at increased risk of cardiovascular morbidity and mortality. We assessed platelet reactivity and reticulated platelets (RPs) in 90 recipients, 51 (56.6%) of whom were not receiving acetylsalicylic acid (ASA) therapy (group A) and 39 (43.3%) who were receiving ASA therapy, 100 mg (group B), and in 60 healthy controls (group C).

Methods

Reticulated platelets were measured using a hematology automated analyzer (XE-2100; Sysmex Corp, Kobe, Japan) and were expressed as the percentage of RPs in the total optical platelet count (immature platelet fraction [IPF]), as the percentage of highly fluorescent RPs, and as the absolute number of RPs (IPF#). Platelet function was assessed using optical aggregometry (platelet aggregation) induced using 1 mmol/L of arachidonic acid, 2 or 10 μmol/L of adenosine diphosphate, or 2 μg/mL of collagen.

Results

Group A demonstrated significantly higher values of RP compared with group B or group C. Group B demonstrated a substantially higher percentage of RPs compared with group C, which was significant only for the IPF parameter. Multiple regression analysis demonstrated that IPF and IPF# were significantly and positively related to collagen-induced platelet aggregation.

Conclusion

We documented the presence of higher concentrations of RPs in transplant recipients compared with a control population, and a significant association between RPs and platelet function.     

Ureteral Complications in Renal Transplant Recipients Successfully Treated With Interventional Radiology

Introduction

Ureteral complications in renal transplantation occur in approximately 8% of renal transplant recipients, occasionally leading to graft loss. This retrospective study presents a single-center experience in managing ureteral complications with interventional radiology as well as the long-term graft function and recipient survival.

Patients and Methods

We analyzed 21 renal transplant recipients with ureteral problems.

Results

Nine patients experienced urinary leak, six patients had ureteric obstruction, and six patients had obstruction preceded by leak. Median recipient age was 48 (range, 20-63) years; 71% (15/21) of the patients were male and 66.6% (14/21) of transplants were derived from cadaveric donors. Ureteral complications were diagnosed at a mean of 18 days (range, 12-47) after renal transplantation. Initially a percutaneous nephrostomy was performed, followed by antegrade placement of a nephroureteral stent. In cases with ureteral obstruction, ureteral balloon dilation was performed prior to placement of the stent. Median time to the procedure was 53 days, and median follow-up for the purposes of this study was 57 months. Renal graft function improved following treatment of the ureteral complication. Mean serum creatinine values prior to and after the intervention were 4.8 ± 2.12 and 1.79 ± 0.58 mg/dL, respectively (P<.0001). Functional renal grafts were observed at the first, third, and fifth posttransplantation year among 100%, 95.2% and 80.9% of patients, respectively. It should be further noted that no graft was lost due to a ureteral complication.

Conclusions

Interventional radiology was successful in treating immediate and long-term ureteral problems among renal transplant recipients with preservation of good renal function and patient survival.     

Complement Genes Strongly Predict Recurrence and Graft Outcome in Adult Renal Transplant Recipients with Atypical Hemolytic and Uremic Syndrome

Atypical hemolytic and uremic syndrome (aHUS) is a severe disease strongly associated with genetic abnormalities in the complement alternative pathway. In renal posttransplantation, few data are available on recurrence risk and graft outcome according to genetic background in aHUS patients. The aim of this study was to identify risk factors for recurrence and transplant outcome and, in particular, the role of complement gene abnormalities. We retrospectively studied 57 aHUS patients who had received 71 renal transplants. A mutation in complement gene was identified in 39 (68%), in factor H (CFH), factor I (CFI), membrane cofactor‐protein (MCP), C3 and factor B (CFB). At 5 years, death‐censored graft survival was 51%. Disease recurrence was associated with graft loss (p = 0.001). Mutations in complement genes were associated with higher risk of recurrence (p = 0.009). Patients with CFH or gain of function (C3, CFB) mutations had a highest risk of recurrence. M‐TOR inhibitor was associated with significant risk of recurrence (p = 0.043) but not calcineurin inhibitor immunosuppressive treatment (p = 0.29). Preemptive plasmatherapy was associated with a trend to decrease recurrence (p = 0.07). Our study highlights that characterization of complement genetic abnormalities predicts the risk of recurrence‐related graft loss and paves the way for future genetically based individualized prophylactic therapeutic strategies.     

Association Between Calcineurin Inhibitor Treatment and Peripheral Nerve Dysfunction in Renal Transplant Recipients

Neurotoxicity is a significant clinical side effect of immunosuppressive treatment used in prophylaxis for rejection in solid organ transplants. This study aimed to provide insights into the mechanisms underlying neurotoxicity in patients receiving immunosuppressive treatment following renal transplantation. Clinical and neurophysiological assessments were undertaken in 38 patients receiving immunosuppression following renal transplantation, 19 receiving calcineurin inhibitor (CNI) therapy and 19 receiving a calcineurin‐free (CNI‐free) regimen. Groups were matched for age, gender, time since transplant and renal function and compared to normal controls (n = 20). The CNI group demonstrated marked differences in nerve excitability parameters, suggestive of nerve membrane depolarization (p < 0.05). Importantly, there were no differences between the two CNIs (cyclosporine A or tacrolimus). In contrast, CNI‐free patients showed no differences to normal controls. The CNI‐treated patients had a higher prevalence of clinical neuropathy and higher neuropathy severity scores. Longitudinal studies were undertaken in a cohort of subjects within 12 months of transplantation (n = 10). These studies demonstrated persistence of abnormalities in patients maintained on CNI‐treatment and improvement noted in those who were switched to a CNI‐free regimen. The results of this study have significant implications for selection, or continuation, of immunosuppressive therapy in renal transplant recipients, especially those with pre‐existing neurological disability.     

Effects of Ureteral Stent on Urologic Complications in Renal Transplant Recipients: A Retrospective Study

The aim of the present study was to analyze the effects of ureteral stents used in renal transplantation on urologic as well as other complications. Cases of renal transplants from living or deceased donors performed in our hospital were retrospectively evaluated. The effects of the routine use of ureteral stents on postoperative complications were investigated. All outcomes and complications encountered during the postoperative follow-up were recorded. The Lich-Gregoire technique, which is a method of extravesical ureteroneocystostomy, was performed on all patients. One hundred and twenty-two patients underwent renal transplantation between 2001 and 2007 in our hospital. Stents were placed routinely in all patients. Leakage was observed in one patient, and one patient developed an obstruction; however, none of the patients developed an infection. A lymphocele developed in one patient. All urologic complications were treated without major morbidity. Graft loss did not occur. Complications following urinary anastomosis have a high rate of morbidity in renal transplantation. Ureteral stenting in renal transplant recipients prevents early urologic complications. The data generated in the current study were compared to the literature.     

The Effect of Pre-existing Ischaemic Heart Disease on Renal Dysfunction in Cardiac Transplant Recipients

Renal dysfunction is a recognized complication of cardiac transplantation and can impact on the life expectancy of an already fragile population. A large proportion of these patients require transplantation because of the consequences of ischaemic heart disease (IHD) which, in turn, is often associated with ischaemic nephropathy. We studied the effect of IHD, diagnosed prior to transplantation, on the renal function of recipients who survived more than 6months after surgery. Of the 168 patients transplanted in a single centre over 15 years, 132 were included in the study. Renal dysfunction was defined as a serum creatinine consistently above 200 micromol/L (2.26 mg/dL). Analysis confirmed that IHD was an independent risk factor for developing renal impairment. In transplant recipients with IHD, closer monitoring is warranted to detect and prevent renal dysfunction or to retard its progression.     

Concomitant Endothelin‐1 Overexpression in Lung Transplant Donors and Recipients Predicts Primary Graft Dysfunction

Primary graft dysfunction (PGD) causes significant morbidity following lung transplantation (LTX). Mortality is high in PGD and therapeutic strategies are limited. To investigate whether endothelin‐1 (ET‐1) that mediates increased vascular permeability and edema formation in lung grafts can predict PGD, ET‐1 mRNA expression was examined in lung tissue biopsies of 105 donors and recipients obtained shortly before LTX. Serum ET‐1 concentration was assessed by ELISA. PGD grade was diagnosed and scored by oxygenation and radiological characteristics according to ISHLT guidelines. PGD grade 3 developed in 11% of patients. ET‐1 mRNA expression was significantly increased in both donor (p < 0.0001) and recipient (p = 0.01) developing PGD as compared to no PGD group. Pretransplant ET‐1 serum concentrations were elevated in recipients with PGD as compared to no PGD group (p < 0.0001), although serum ET‐1 was not different between donors whose grafts developed PGD grades 0–3. In regression analysis, concomitant elevated donor tissue ET‐1 and recipient serum ET‐1 predicted PGD grade 3. This study indicates that pretransplant ET‐1 mRNA overexpression in donors associated with elevated pretransplant serum ET‐1 in recipients contribute to PGD development and that their assessment might be beneficial to predict PGD and to identify recipients who could benefit from a targeted ET‐1 blockade.