Long-term results of kidney transplantation in patients with familial mediterranean fever.

INTRODUCTION: Long-term kidney transplantation (KT) results in patients with familial Mediterranean fever (FMF)-related amyloidosis are not well studied. This study reviewed the long-term survival outcomes of FMF patients who underwent KT. METHODS: We compared the outcomes of 31 patients who underwent (KT) for biopsy-proven amyloidosis secondary to FMF with 31 control patients (five with diabetes mellitus and 26 with nondiabetic kidney disease) undergoing KT between 1994 and 2021 at Baskent University Hospital. All data were recorded retrospectively from patients' files. RESULTS: THE MEDIAN AGE (QUARTILE DEVIATION: QD) at the time of KT in the FMF and control group were 31 (6.7) and 33 (11), respectively. The median follow-up period (QD) after KT was 108 (57) months in the FMF and 132 (72) months in the control group. In the FMF group, graft and patient survivals were 71% and 84% at 5 years and 45% and 48% at 10 years, respectively. In the control group, graft and patient survivals were 79% and 100% at 5 years and 63% and 71% at 10 years, respectively. Patient survival in the FMF group at 5 years was significantly lower than in the control group (p = .045). There was no statistically significant difference between the FMF and control groups in terms of graft and patient survival, and serum creatinine levels at 10 years. All patients were given triple immunosuppressive treatment with cyclosporine, mycophenolate mofetil, and prednisolone. Three patients received anakinra and one received canakinumab in addition to colchicine treatment. One FMF patient also underwent heart transplantation due to AA amyloidosis. Of the FMF patients, 11 died during follow-up. CONCLUSION: We have found that the long-term outcome of KT in patients with FMF amyloidosis is numerically worse but not statistically different from the control group. However, short- and long-term complications still need to be resolved.

Living Kidney Donation Criteria of Baskent University.

OBJECTIVES: Kidney transplant is the best treatment for patients with end-stage renal disease. Preparation of living related kidney donors and recipients is the major step to achieve their best long-term outcomes. Here, we present the Baskent University criteria for living kidney donors and recipients. MATERIALS AND METHODS: The Baskent team has performed >2000 kidney transplants from 1985 to 2022 under leadership of Prof. Mehmet Haberal, a transplantation pioneer in Turkey, who facilitated Turkish legislation on procurement, storage, engraftment, and transplant of organs and tissues in June 1979, which has been adopted in other countries with few changes. Although the main frame is similar, we have constant principles in kidney donation. Baskent University is now known as an exceptional transplant center in Turkey, the Middle East, Europe, and the world and has established its own donor criteria for both kidney and liver transplant. RESULTS: Volunteerism remains a core principle of living kidney donation, regardless of other criteria. At Baskent University, donor protection from social, psychological, and health problems is paramount. Loss-profit and risk of transplant are assessed for every case. Donors must be followed up and remedies sought for failed criteria. Dr. Haberal's principles are the basis of Baskent University donation criteria, and unrelated kidney transplant donors are accepted only in cases of cross-donation. Major distinctions of Baskent University's living related donor criteria are (1) absence of unrelated or nondirected donation, (2) lowest acceptable donor glomerular filtration rate of 100 mL/min, (3) rejection of hypertensive donor candidates (regardless of medication), and (4) obesity must be corrected before transplant if body mass index (measured as body weight in kilograms divided by height in meters squared) is >30. CONCLUSIONS: The Baskent University donor selection criteria provide excellent long-term outcomes of kidney donors that have been proved by our recent studies.

Long-Term Follow-up of Over 600 Living Related Kidney Donors: Single-Center Experience.

OBJECTIVES: Kidney transplant is the treatment of choice in patients with end-stage renal disease because it offers improved survival and better quality of life. Although most epidemiologic studies have suggested that living kidney donors have a minimal lifetime risk of developing end-stage renal disease, long-term complications and physiologic and psychologic sequelae resulting from donation remain unclear. Here, we examined the long-term results of living-related kidney donors who donated kidneys at the Baskent University Ankara Hospital over the past 25 years. MATERIALS AND METHODS: We were able to examine 607 kidney transplant donors (mean age of 52.03 ± 11.54 years) who were seen at our center from 1986 to 2021 and who agreed to a general health evaluation. Collected data included donor age, sex, blood type, body mass index, duration after donation, blood pressure measurements, biochemical parameters, abdominal ultrasonograph for size, structure, and renal blood flow of the solitary kidney, comorbid conditions, chronic drug use, and surgical procedures after donation. RESULTS: Mean time after donation was 10.4 ± 3.2 years. Twenty-four donors (3.9%) were diagnosed with diabetes and 21 (3.4%) with thyroid disease, 64 (10.5%) developed hypertension, and 48 (8.8%) developed atherosclerotic cardiovascular disease. Obesity was found to be an increasing problem in our donor population, with 174 (28.6%) developing mild to moderate obesity (body mass index >25 kg/m2). Older age, obesity, smoking, and hyperlipidemia were found to be the major and independent risk factors of both hypertension and atherosclerotic cardiovascular disease in donors. None of our donors developed endstage renal disease. CONCLUSIONS: Obesity and hypertension were the most common comorbidities that developed in our kidney donor population. Our principle is to avoid unrelated and nondirected donors because of the possible long-term complications. Unrelated donors may be desperate if a family member needs donation in the future.

Tacrolimus intrapatient variability in BK virus nephropathy and chronic calcineurin toxicity in kidney transplantation.

Intrapatient variability (IPV) in tacrolimus has been increasingly acknowledged as a risk factor for poor graft survival after kidney transplantation. Although past studies have mainly accounted for IPV in acute or chronic rejection states as due to underimmunosuppression, this is not yet clear. So far, tacrolimus IPV for BK virus-associated nephropathy (BKVN) and chronic calcineurin inhibitor toxicity (CNIT) has not been investigated. Here, we evaluated IPV in tacrolimus for BKVN and chronic CNIT, which are mainly considered as overimmunosuppression states. In this case-control study, kidney allograft biopsies conducted between 1998 and 2018 were included, with patients grouped by biopsy results as BKVN alone group, CNIT alone group, and normal graft function (control group). IPV was estimated as mean absolute deviation. Our study groups included 25 kidney transplant recipients with BKVN alone, 91 patients with CNIT alone, and 60 patients with normal 5-year graft survival (control group). In analyses of IPV in tacrolimus six months before graft biopsy, IPV was highest in the BKVN group (P = 0.001). The BKVN group also had the highest IPV in tacrolimus at 12 months after biopsy (P = 0.001), with all pairwise comparisons statistically different between groups. At 12 months after biopsy, five patients (20%) in the BKVN group and 10 patients (10.9%) in the CNIT group had graft loss. Among other risk factors, BKVN and chronic CNIT are consequences related to high IPV. Quantification of IVP for tacrolimus in clinical practice would help to optimize kidney transplant outcomes.

Incidence and Immunologic Analysis of Coronavirus Disease (COVID-19) in Hemodialysis Patients:A Single-Center Experience.

OBJECTIVES: COVID-19 is a great threat to the modern world and significant threat to immunocompromised patients, including patients with chronic renal failure. We evaluated COVID-19 incidence among our hemodialysis patients and investigated the most probable immune mechanisms against COVID-19. MATERIALS AND METHODS: Baskent University has 21 dialysis centers across Turkey, with 2420 patients on hemodialysis and 30 on peritoneal dialysis. Among these, we retrospectively evaluated 602 patients (257 female/345 male) with chronic renal failure receiving hemodialysis as renal replacement therapy; 7 patients (1.1%) were infected with SARS-CoV-2. We retrospectively collected patient demographic characteristics, clinical data, and immunological factors affecting the clinical course of the disease. We divided patients into groups and included 2 control groups (individuals with normal renal functions): group I included COVID-19-positive patients with normal renal function, group II included COVID-19-positive hemodialysis patients, group III included COVID-19-negative hemodialysis patients, and group IV included COVID-19-negative patients with normal renal function. Lymphocyte subsets in peripheral blood and typing of human leukocyte antigens were analyzed in all groups, with killer cell immunoglobulin like receptor genes analyzed only in COVID-19-positive patients and healthy controls. RESULTS: No deaths occurred among the 7 COVID-19-positive hemodialysis patients. Group I patients were significantly older than patients in groups II and III (P = .039, P = .030, respectively) but not significantly different from group IV (P = .060). Absolute counts of natural killer cells in healthy controls were higherthan in other groups (but not significantly). ActivatedT cells were significantly increased in both COVID-19-positive groups versus COVID-19-negative groups. Groups showed significant differences in C and DQ loci with respect to distribution of alleles in both HLA classes. CONCLUSIONS: Although immunocompromised patients are at greater risk for COVID-19, we found lower COVID-19 incidence in our hemodialysis patients, which should be further investigated in in vitro and molecular studies.

Risk Factors of Antibody-Mediated Rejection and Predictors of Outcome in Kidney Transplant Recipients.

OBJECTIVES: Kidney transplant is the treatment of choice for patients with end-stage renal disease. Antibody-mediated rejection is associated with higher rates of graft loss in kidney transplant recipients. Determining the risk factors of antibody-mediated rejection is vital for its prevention, early diagnosis, and appropriate treatment, as these factors may be important in maintaining long-term graft survival in transplant recipients. In our study, we analyzed the risk factors of antibody-mediated rejection in kidney transplant recipients and the negative impact of antibody-mediated rejection on graft function. MATERIALS AND METHODS: We analyzed demographic and clinical data of 124 kidney transplant recipients (37 female [30%] and 87 male [70%] patients) who were diagnosed with antibody-mediated rejection at transplant biopsy. We compared graft outcomes of this patient cohort versus 75 kidney transplant recipients (24 female [32%] and 51 male [68%] patients) who were not diagnosed with antibody-mediated rejection. RESULTS: Mean ages of patients with and without antibody-mediated rejection were 38.2 ± 13.6 and 34.4 ± 13.0 years, respectively. Mean ages of donors for patients with antibody-mediated rejection was significantly higher (48.0 ± 13.2 y) than for donors of patients without antibody-mediated rejection (47.1 ± 11.4 y; P < .05). Rate of graft loss was 15.3% in patients with antibody-mediated rejection; patients without antibody-mediated rejection had no graft loss (P < .05). Positive panel reactive antibody levels and blood transfusion before transplant were found to be risk factors of antibody-mediated rejection in kidney transplant recipients. However, recipients who received tacrolimus had less antibody-mediated rejection episodes than recipients who received sirolimus or cyclophosphamide. CONCLUSIONS: Antibody-mediated rejection is associated with high rates of graft loss in kidney transplant recipients. Avoiding blood transfusion, lowering panel reactive antibody levels, choosing younger donors, and using tacrolimus in high-risk kidney transplant recipients may reduce antibody-mediated rejection rates and provide better graft survival.

Risk Factors and Treatment Options for Persistent Hyperparathyroidism After Kidney Transplantation.

BACKGROUND: Kidney transplantation (KT) corrects secondary hyperparathyroidism. However, persistent hyperparathyroidism (pHPT) may be observed in some patients post-KT. This study aims to evaluate the risk factors and treatment options for pHPT. MATERIALS AND METHODS: The study population comprises 1054 patients who underwent KT between January 2001 and May 2019. Serum samples were analyzed for calcium (Ca), phosphorus, creatinine, intact parathyroid hormone (iPTH) and estimated glomerular filtration rate. RESULTS: The prevalence of pHPT following KT is 14%. Ninety pHPT patients were compared with 550 non-pHPT patients. The median duration of pre-KT dialysis was longer, and pre-KT serum Ca, P, and iPTH levels were significantly higher in the pHPT group than the non-HPT group. The pHPT of 46 patients (51%) received medical treatment. The remaining 44 patients (49%) had parathyroidectomy (PTx) if symptoms or signs (or both) of pHPT continued. Subtotal PTx was performed in 35 patients, and minimally invasive PTx was performed in 9 patients. CONCLUSION: Based on our study results, the most important risk factors for post-KT pHPT are long dialysis duration and high pre-KT iPTH levels. In patients who underwent KT, if pHPT lasts longer than 1 year, surgical treatment is the recommended approach. Based on our experience, the treatment method to be performed in pHPT should be 3+1/2 PTx.

Over 5 Years of Excellent Graft Kidney Function Determinants: Baskent University Experience.

OBJECTIVES: Kidney graft survival may be evaluated according to the duration of time with a functioning graft. Survival alone may not satisfy expectations of a successful kidney transplant if the graft kidney does not show excellent function. In our study, we analyzed the characteristics of kidney transplant recipients who showed excellent graft function after 5 to 10 years of follow-up in an aim to improve graft survival and to ensure the best kidney function in the long term. MATERIALS AND METHODS: We retrospectively evaluated graft function and demographic characteristics of 288 patients who underwent kidney transplant between January 2008 and December 2012. RESULTS: We found that 149 patients (51.7%) had excellent graft function, 88 patients (30.5%) had a functioning graft with a glomerular filtration rate lower than 60 mL/min and/or had signs of graft kidney dysfunction, and 45 patients (15.6%) experienced graft loss. Of 288 kidney transplant recipients enrolled in the study, most were male (56%), and mean age was 30.47 ± 14.36 years at time of transplant. Median time on dialysis was 39.09 ± 59.30 months. The overall graft survival rate in the patient group was 82.2% after 5 to 10 years of follow-up. Multivariate analysis showed that excellent graft survival predictors beyond 5 years were negative panel reactive antibody levels, lower donor age, shorter duration on dialysis, absence of acute rejection episodes, 3 or less HLA mismatches, lower immunosuppressive levels, and lower recipient age at transplant. CONCLUSIONS: Lower panel reactive antibody levels, lower donor age, shorter duration on dialysis, absence of acute rejection episodes, 3 or less HLA mismatches, and lower recipient age at transplant are major determinants of excellent graft survival in our kidney transplant recipients.

Renin-Angiotensin System Blockage and Avoiding High Doses of Calcineurin Inhibitors Prevent Interstitial Fibrosis and Tubular Atrophy in Kidney Transplant Recipients.

OBJECTIVES: Chronic allograft dysfunction is a complex and multifactorial process characterized by progressive interstitial fibrosis and tubular atrophy. The finding of interstitial fibrosis and tubular atrophy is prevalent among kidney transplant patients receiving a calcineurin inhibitor-based immunosuppressive regimen and may be considered as a surrogate of allograft survival. Both immune (acute rejection episodes, sensitization, and HLA incompatibility) and nonimmune (donor age, delayed graft function, calcineurin inhibitor toxicity, infections, and hypertension) mechanisms play a role in chronic allograft dysfunction, and different causes all lead to similar histologic and clinical final pathways, with the end result of graft loss. In our study, we aimed to compare the outcomes of kidney transplant recipients with or without interstitial fibrosis and tubular atrophy in protocol biopsies to determine the conditions that may affect allograft survival. MATERIALS AND METHODS: We divided 192 kidney transplant recipients into 2 groups (96 patients with interstitial fibrosis and tubular atrophy; 96 patients without interstitial fibrosis and tubular atrophy) according to protocol biopsy at 6 months. Patient groups were compared according to their risk factors for chronic allograft dysfunction (cold ischemia time, delayed graft function, donor age, infections, mean blood calcineurin levels, and hypertension). RESULTS: Cold ischemia time, delayed graft function, high 24-hour proteinuria levels, and higher mean blood calcineurin levels were found to be major risk factors for poor graft function in kidney transplant recipients with interstitial fibrosis and tubular atrophy. Renin-angiotensin system blockage with either angiotensin-converting enzyme inhibitors or angiotensin receptor blockers was found to be preventive for interstitial fibrosis and tubular atrophy after kidney transplant. CONCLUSIONS: Preventing prolongation of cold ischemia time, lowering blood cholesterol levels, angiotensin-converting enzyme inhibitors and angiotensin receptor blocker treatment even without existing proteinuria and avoiding higher doses of calcineurin inhibitors should be major approaches in kidney transplant recipients.

Obesity and Loss of Kidney Function: Two Complications to Face for Older Living Kidney Donors.

OBJECTIVES: Although living kidney donors have a minimal lifetime risk of developing end-stage renal disease, long-term complications and physiologic and psychologic sequelae resulting from donation remain unclear because of lack of optimum follow-up after transplant. Here, we evaluated renal function, complications, and physical and mental performance of living kidney donors. MATERIALS AND METHODS: We evaluated 147 patients who donated living kidneys between 1981 and 2012 at Baskent University Hospital. We collected data on donor age, sex, body mass index, smoking status, hypertension before and after nephrectomy, proteinuria, estimated glomerular filtration rate according to the Modification of Diet in Renal Disease formula, and duration after donation. All donors answered the Medical Outcomes Study short-form general health survey; results were evaluated according to answers to 11 questions totaling 22 points. RESULTS: Body mass index of donors showed that 31 (21.1%) were in normal range, 66 (44.9%) had mild obesity (body mass index of 26-30 kg/m²), and 30 (34%) had moderate to high obesity (body mass index > 30 kg/m2). Results from the general health survey showed that 117 donors (80%) had no loss, 13 (9%) had mild loss, 12 (8%) had moderate loss, and 5 (3%) had high loss of ability. When we compared estimated glomerular filtration rates according to donor age, donors who were 18 to 34 years had a mean estimated glomerular filtration rate of 113.5 ± 40, donors 35 to 49 years had a mean rate of 95.01 ± 23.4, donors 50 to 64 years had a mean rate of 87.43 ± 25.4, and donors older than 65 years had a mean rate of 63.76 ± 11.35 mL/min/1.73 m², revealing a statistically significant loss of kidney function with aging (P = .001).. CONCLUSIONS: Careful evaluation of kidney donors before and after donation is essential for the most common risk factors, such as obesity, and for loss of kidney function, especially in older donors.

Assessment of myocardial mechanics in patients with end-stage renal disease and renal transplant recipients using speckle tracking echocardiography.

OBJECTIVES: Velocity vector imaging allows quantitation of myocardial strain and strain rate from 2-dimensional images based on speckle tracking echocardiography. The aim of this study was to analyze the changes in myocardial strain and strain rate patterns in patients with end-stage renal disease and renal transplant recipients. MATERIALS AND METHODS: We studied 33 patients with end-stage renal disease on hemodialysis (19 men; mean age, 36 ± 8 y), 24 renal transplant recipients with functional grafts (21 men; mean age, 36 ± 7 y) and 26 age- and sex-matched control subjects. Longitudinal peak systolic strain and strain rate for basal, mid, and apical segments of the left ventricular wall were determined by velocity vector imaging from apical 4- and 2-chamber views. The average longitudinal strain and strain rate for the left ventricle were noted. From short-axis views at the level of papillary muscles, average circumferential, and radial strain, and strain rate were assessed. RESULTS: Mean heart rate and systolic and diastolic blood pressure during imaging were similar between the groups. Longitudinal peak systolic strain and strain rate at basal and mid-segments of the lateral wall were significantly higher in renal transplant recipients and control groups than endstage renal disease patients. Average longitudinal systolic strain from the 4-chamber view was highest in control subjects (-14.5% ± 2.9%) and was higher in renal transplant recipients (-12.5% ± 3.0%) than end-stage renal disease patients (-10.2% ± 1.6%; P ≤ .001). Radial and circumferential strain and strain rate at the level of the papillary muscle were lower in patients with end-stage renal disease than other groups. CONCLUSIONS: Differences in myocardial function in patients with end-stage renal disease, renal transplant recipients, and normal controls can be quantified by strain imaging. Myocardial function is improved in renal transplant recipients compared with end-stage renal disease patients.

Comparison of preemptive kidney transplant recipients with nonpreemptive kidney recipients in single center: 5 years of follow-up.

BACKGROUND: For suitable patients with end-stage renal disease, kidney transplantation (KT) is the best renal replacement therapy, resulting in lower morbidity and mortality rates and improved quality of life. Preemptive kidney transplantation (PKT) is defined as transplantation performed before initiation of maintenance dialysis and reported to be associated with superior outcomes of graft and patient survival. In our study, we aimed to compare the 5-year outcomes of PKT and nonpreemptive kidney transplantation (NPKT) patients who received KT in our center, to define the differences according to complications, comorbidities, adverse effects, clinical symptoms, periodical laboratory parameters, rejection episodes, graft, and patient survival. METHODS: One hundred kidney transplantation (37 PKT, 63 NPKT) recipients were included in our study. All patients were evaluated for adverse effects, complications, comorbidities, clinical symptoms, monthly laboratory parameters, acute rejection episodes, graft, and patient survival. RESULTS: Acute rejection episodes were found to be significantly correlated with graft loss in both groups (P = 0.02 and P = 0.01, respectively). Hypertension after transplantation was diagnosed by ambulatory blood pressure measurement in 74 of 100 patients. Twenty-five of 37 (67.6%) of Group 1 (PKT) recipients had hypertension while 54 of 63 (85.4%) of Group 2 (NPKT) had hypertension. The incidence of hypertension between two groups was statistically significant (P = 0.03), but this finding was not correlated to graft survival (P = 0.07). Some patients had serious infections, requiring hospitalization, and were treated immediately. Infection rates between the two groups were 10.8% for Group 1 patients and 31.7% for Group 2 patients and were statistically significant (P = 0.02). Infection, requiring hospitalization, was found to be statistically correlated to graft loss in only NPKT patients (P = 0.00). CONCLUSION: While the comparison of PKT and graft and patient survival with NPKT is poorer than we expected, lower morbidity rates of hypertension and infection are similar with recent data. Avoidance of dialysis-associated comorbidities, diminished immune response, and cardiovascular complications are the main benefits of PKT.

Is there a link between hyperuricemia, morning blood pressure surge, and non-dipping blood pressure pattern in metabolic syndrome patients?

BACKGROUND: Hypertensive patients usually have a blunted nocturnal decrease, or even increase, in blood pressure during sleep. There is also a tendency for increased occurrence of cardiovascular events between 6 and 12 am due to increased morning blood pressure surge (MBPS). Co-occurrence of metabolic syndrome (MetS) and hypertension is also a common problem. Hyperuricemia might trigger the development of hypertension, chronic renal failure, and insulin resistance. In this study, we aimed to determine whether there is a relationship between hyperuricemia, MetS, nocturnal blood pressure changes, and MBPS. METHOD: A total of 81 newly diagnosed hypertensive MetS patients were included in this study. Ambulatory blood pressure monitoring of patients was done and patients' height, weight, and waist and hip circumferences were recorded. Fasting blood glucose (FBG), lipid profile, creatinine, potassium, uric acid, hematocrit levels were studied. RESULTS: Non-dipper (ie, those whose blood pressure did not drop overnight) patients had higher waist-hip ratios (WHR) (P = 0.003), uric acid (P = 0.0001), FBG (P = 0.001), total and low-density lipoprotein cholesterol levels (P = 0.0001). Risk analysis revealed that hyperuricemia was a risk factor for non-dipping pattern (P < 0.0001, odds ratio = 8.1, 95% confidence interval = 1.9-33.7). Patients in the highest quadrant for uric acid levels had higher FBG (P = 0.001), low-density lipoprotein cholesterol (P = 0.017), WHR (P = 0.01), MBPS (P = 0.003), and night diastolic blood pressure compared with lowest quadrant patients (P = 0.013). Uric acid levels were also positively correlated with night ambulatory blood pressure (ABP) (r = 0.268, P =0.05), night diastolic blood pressure (r =0.3, P =0.05), and MBPS (r =0.3, P =0.05). CONCLUSION: Evaluation of hypertensive patients should also include an assessment of uric acid level and anthropometric measurements such as abdominal obesity. Hyperuricemia seems to be closely related to undesired blood pressure patterns and this may signal to the clinician that an appropriate therapeutic approach is required.

Evaluation of coronary microvascular function in patients with end-stage renal disease, and renal allograft recipients.

BACKGROUND: Approximately half of all deaths in patients with end-stage renal disease (ESRD) are due to cardiovascular diseases. Although renal transplant improves survival and quality of life in these patients, cardiovascular events significantly affect survival. We sought to evaluate coronary flow reserve (CFR), an indicator of coronary microvascular function, in patients with ESRD and in patients with a functioning kidney graft. METHODS: Eighty-six patients (30 with ESRD, 30 with a functioning renal allograft, and 26 controls) free of coronary artery disease or diabetes mellitus were included. Transthoracic Doppler echocardiography was used to measure coronary peak flow velocities at baseline and after dipyridamole infusion. CFR was calculated as the ratio of hyperemic to baseline diastolic peak flow velocities and was compared among the groups. RESULTS: The mean age of the study population was 36.1+/-7.3 years. No between-group differences were found regarding age, sex, or prevalences of traditional coronary risk factors other than hypertension. Compared with the renal transplant and control groups, the ESRD group had significantly lower mean CFR values. On multivariate regression analysis, serum levels of creatinine, age, and diastolic dysfunction were independent predictors of CFR. CONCLUSIONS: CFR is impaired in patients with ESRD suggesting that coronary microvascular dysfunction, an early finding of atherosclerosis, is evident in these patients. Although associated with a decreased CFR compared with controls, renal transplant on the other hand seems to have a favorable effect on coronary microvascular function.