Carotid intima-media thickness as a cardiovascular risk marker in pediatric end-stage renal disease patients on dialysis and in renal transplantation

Long-term Effects of Kidney Transplantation Compared With Dialysis on Intima-media Thickness in Children-Results From the 4C-T Study

BACKGROUND

Children requiring kidney replacement therapy experience high burden of cardiovascular (CV) disease leading to increased mortality. Intima-media thickness (IMT) indicating atherosclerosis is a validated surrogate marker for future CV events.

METHODS

We investigated the effect of different treatment modalities (dialysis, preemptive kidney transplantation (KTx), late KTx after dialysis) on IMT by multivariable linear mixed-effect modeling. Patients were enrolled in a prospective cohort study.

RESULTS

A total of 261 analyzed children had a mean follow-up of 3 y. Children after preemptive and late KTx had lower levels of IMT when compared with dialysis. Using an interaction term, a significant progression of IMT over time was seen during dialysis (β = 0.0053 mm/y, P   =  0.004). IMT before the start of therapy was the most influential determinant in all models. Low IMT was associated with maintenance steroid treatment after preemptive KTx. High IMT on dialysis was associated with higher systolic blood pressure, lower body mass index, lower serum albumin, and lower bicarbonate.

CONCLUSIONS

IMT remained rather stable in children several years after KTx. In contrast, children on dialysis had higher IMT values, which increased over time. In these children, blood pressure control, calorie and protein intake, and acid-base homeostasis seem important. Taken together, children might profit from early transplantation to limit accumulation of CV risk.

Cardiovascular involvement after liver transplantation: role of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis

Patients submitted to liver transplantation (LT) are exposed to high risk of cardiovascular (CV) complications which are the main determinants of both short-term and long-term morbidity and mortality in LT. Non-alcoholic fatty liver disease (NAFLD) is a very frequent condition in general population and is associated with a high risk of cardiovascular disease (CVD) which represents the first cause of death of these patients. NAFLD is predicted to become the first indication to LT and nowadays is also frequently detected in patients submitted to LT for other indications. Thus, the risk of CVD in patients submitted to LT is forecasted to increase in the next years. In this review the extent of CV involvement in patients submitted to LT and the role of NAFLD, either recurring after transplantation or as de novo presentation, in increasing CV risk is analysed. The risk of developing metabolic alterations, including diabetes, hypertension, dyslipidemia and weight gain, all manifestations of metabolic syndrome, occurring in the first months after LT, is depicted. The different presentations of cardiac involvement, represented by early atherosclerosis, coronary artery disease, heart failure and arrhythmias in patients with NAFLD submitted to LT is described. In addition, the tools to detect cardiac alterations either before or after LT is reported providing the possibility for an early diagnosis of CVD and an early therapy able to reduce morbidity and mortality for these diseases. The need for long-term concerted multidisciplinary activity with dietary counseling and exercise combined with drug treatment of all manifestations of metabolic syndrome is emphasized.

Cardiovascular Risk Factors are Inversely Associated With Omega-3 Polyunsaturated Fatty Acid Plasma Levels in Pediatric Kidney Transplant Recipients

OBJECTIVES

High plasma levels of the omega-3 fatty acids eicosapentaenoic acid (EPA), docosahexaenoic acid, and docosapentaenoic acid associates with positive outcomes in adult renal transplant recipients. However, data from pediatric populations are scarce. The aim of the study was to assess the fatty acid profile in a pediatric renal transplantation cohort and to examine the associations between plasma omega-3 fatty acids and cardiovascular disease (CVD) risk factors.

METHODS

In this cross-sectional study comprising 53 children (median age, 12.2 years; 32 boys) with a renal transplant, we assessed the prevalence of CVD risk factors as well as markers of end organ damage: carotid intima-media thickness (cIMT) and left ventricular mass index. The associations between plasma omega-3 fatty acids and CVD risk factors were assessed.

RESULTS

Twenty-five (47%) patients were preemptively transplanted. Seventy-six percent had dyslipidemia and 51% had hypertension. The mean left ventricular mass index was 40.4 ± 14.3 g/m^2.7, and 14% had left ventricular hypertrophy. The mean cIMT was 0.41 ± 0.04 mm. In a multivariate linear regression, EPA levels were inversely associated to blood pressure (β coeff. = -0.37, P = .007), triglycerides (β coeff. = -0.44, P = .01), and high-density lipoprotein cholesterol (β coeff. = -0.41, P = .01).

CONCLUSION

EPA levels are inversely associated with components of the metabolic syndrome, which may provide support for specific dietary advice or supplementation in this patient population. cIMT is less pronounced in our cohort than in comparable cohorts with lower rate of preemptive transplantations. Our results need replication in prospective cohorts.

Effects of Hemodiafiltration versus Conventional Hemodialysis in Children with ESKD: The HDF, Heart and Height Study

BACKGROUND

Hypertension and cardiovascular disease are common in children undergoing dialysis. Studies suggest that hemodiafiltration (HDF) may reduce cardiovascular mortality in adults, but data for children are scarce.

METHODS

The HDF, Heart and Height study is a nonrandomized observational study comparing outcomes on conventional hemodialysis (HD) versus postdilution online HDF in children. Primary outcome measures were annualized changes in carotid intima-media thickness (cIMT) SD score and height SD score.

RESULTS

We enrolled 190 children from 28 centers; 78 on HD and 55 on HDF completed 1-year follow-up. The groups were comparable for age, dialysis vintage, access type, dialysis frequency, blood flow, and residual renal function. At 1 year, cIMT SD score increased significantly in children on HD but remained static in the HDF cohort. On propensity score analysis, HD was associated with a +0.47 higher annualized cIMT SD score compared with HDF. Height SD score increased in HDF but remained static in HD. Mean arterial pressure SD score increased with HD only. Factors associated with higher cIMT and mean arterial pressure SD-scores were HD group, higher ultrafiltration rate, and higher β2-microglobulin. The HDF cohort had lower β2-microglobulin, parathyroid hormone, and high-sensitivity C-reactive protein at 1 year; fewer headaches, dizziness, or cramps; and shorter postdialysis recovery time.

CONCLUSIONS

HDF is associated with a lack of progression in vascular measures versus progression with HD, as well as an increase in height not seen in the HD cohort. Patient-related outcomes improved among children on HDF correlating with improved BP control and clearances. Confirmation through randomized trials is required.

Comparison of BMI, waist circumference, and waist-to-height ratio for identification of subclinical cardiovascular risk in pediatric kidney transplant recipients

BACKGROUND

Kidney transplant recipients are at high risk for CV morbidity. However, the measure of obesity that best predicts CV risk has not been established.

OBJECTIVE

A prospective, controlled study was conducted to compare the ability of BMI, WC, and WHr to identify CV risk in pediatric kidney transplant recipients.

METHODS

Transplant recipients, aged 3-20 years, had echocardiogram, CIMT, BMI, WC, WHr, blood pressure, lipids, and leptin measured. Receiver operating characteristic analysis was used to compare the ability of BMI, WC, and WHr to detect a composite adverse CV outcome. Presence of the composite outcome was defined by ≥3 of the following five criteria: (a) LVH, (b) high CIMT, (c) impaired myocardial strain, (d) dyslipidemia, and/or (e) hypertension. Multivariate analysis was conducted by generalized estimating equation regression.

RESULTS

We analyzed 108 visits of 42 transplant recipients. Prevalence of obesity by WHr (43.5%) was higher than BMI (24.1%) and WC (12.0%). Proportion of WHr-obese who met criteria for the adverse CV outcome was higher (62.2%) than BMI (34.6%) and WC-obese (33.3%). Leptin levels were higher in children with obesity. Area under the ROC curve for WHr-obese (0.77) was higher compared to BMI (0.47) and WC (0.48) to detect the CV outcome, P = 0.0006. WHr-obesity was associated with 5.72 increased odds of having the adverse CV outcome, P = 0.0001, while BMI and WC were not significant.

CONCLUSION

WHr is more sensitive than BMI or WC to detect subclinical CV risk and should be included in screening of pediatric kidney transplant recipients.

Effect of haemodiafiltration vs conventional haemodialysis on growth and cardiovascular outcomes in children - the HDF, heart and height (3H) study

BACKGROUND

Cardiovascular disease is prevalent in children on dialysis and accounts for almost 30% of all deaths. Randomised trials in adults suggest that haemodiafiltration (HDF) with high convection volumes is associated with reduced cardiovascular mortality compared to high-flux haemodialysis (HD); however paediatric data are scarce. We designed the haemodiafiltration, heart and height (3H) study to test the hypothesis that children on HDF have an improved cardiovascular risk profile, growth and nutritional status and quality of life, compared to those on conventional HD. We performed a non-randomised parallel-arm intervention study within the International Paediatric Haemodialysis Network Registry comparing children on HDF and conventional HD to determine annualised change in cardiovascular end-points and growth. Here we present the 3H study design and baseline characteristics of the study population.

METHODS

190 children were screened and 177 (106 on HD and 71 on HDF) recruited from 28 centres in 10 countries. There was no difference in age, underlying diagnosis, comorbidities, previous dialysis therapy, dialysis vintage, residual renal function, type of vascular access or blood flow between HD and HDF groups. High flux dialysers were used in 63% of HD patients and ultra-pure water was available in 52%. HDF patients achieved a median convection volume of 13.3 L/m²; this was associated with the blood flow rate only ((p = 0.0004, r = 0.42) and independent of access type (p = 0.38).

DISCUSSION

This is the largest study on dialysis outcomes in children that involves deep phenotyping across a wide range of cardiovascular, anthropometric, nutritional and health-related quality of life measures, to test the hypothesis that HDF leads to improved cardiovascular and growth outcomes compared to conventional HD.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02063776 . The trial was prospectively registered on the 14 Feb 2014.

Cardiovascular effects of metabolic syndrome after transplantation: convergence of obesity and transplant-related factors

Children are at increased risk of developing metabolic syndrome (MS) after kidney transplantation, which contributes to long-term cardiovascular (CV) morbidities and decline in allograft function. While MS in the general population occurs due to excess caloric intake and physical inactivity, additional chronic kidney disease and transplant-related factors contribute to the development of MS in transplant recipients. Despite its significant health consequences, the interplay of the individual components in CV morbidity in pediatric transplant recipients is not well understood. Additionally, the optimal methods to detect early CV dysfunction are not well defined in this unique population. The quest to establish clear guidelines for diagnosis is further complicated by genetic differences among ethnic groups that necessitate the development of race-specific criteria, particularly with regard to individuals of African descent who carry the apolipoprotein L1 variant. In children, since major CV events are rare and traditional echocardiographic measures of systolic function, such as ejection fraction, are typically well preserved, the presence of CV disease often goes undetected in the early stages. Recently, new noninvasive imaging techniques have become available that offer the opportunity for early detection. Carotid intima-media thickness and impaired myocardial strain detected by speckle tracking echocardiography or cardiac magnetic resonance are emerging as early and sensitive markers of subclinical CV dysfunction. These highly sensitive tools may offer the opportunity to elucidate subtle CV effects of MS in children after transplantation. Current knowledge and future directions are explored in this review.

Hypertension in the Pediatric Kidney Transplant Recipient

Hypertension after kidney transplant is a frequent occurrence in pediatric patients. It is a risk factor for graft loss and contributes to the significant burden of cardiovascular disease (CVD) in this population. The etiology of posttransplant hypertension is multifactorial including donor factors, recipient factors, medications, and lifestyle factors similar to those prevalent in the general population. Ambulatory blood pressure monitoring has emerged as the most reliable method for measuring hypertension in pediatric transplant recipients, and many consider it to be essential in the care of these patients. Recent technological advances including measurement of carotid intima-media thickness, pulse wave velocity, and myocardial strain using specked echocardiography and cardiac magnetic resonance imaging have improved our ability to assess CVD burden. Since hypertension remains underrecognized and inadequately treated, an early diagnosis and an appropriate control should be the focus of therapy to help improve patient and graft survival.

Cardiovascular risk after orthotopic liver transplantation, a review of the literature and preliminary results of a prospective study

Improved surgical techniques and greater efficacy of new anti-rejection drugs have significantly improved the survival of patients undergoing orthotopic liver transplantation (OLT). This has led to an increased incidence of metabolic disorders as well as cardiovascular and cerebrovascular diseases as causes of morbidity and mortality in OLT patients. In the last decade, several studies have examined which predisposing factors lead to increased cardiovascular risk (i.e., age, ethnicity, diabetes, NASH, atrial fibrillation, and some echocardiographic parameters) as well as which factors after OLT (i.e., weight gain, metabolic syndrome, immunosuppressive therapy, and renal failure) are linked to increased cardiovascular mortality. However, currently, there are no available data that evaluate the development of atherosclerotic damage after OLT. The awareness of high cardiovascular risk after OLT has not only lead to the definition of new but generally not accepted screening of high risk patients before transplantation, but also to the need for careful patient follow up and treatment to control metabolic and cardiovascular pathologies after transplant. Prospective studies are needed to better define the predisposing factors for recurrence and de novo occurrence of metabolic alterations responsible for cardiovascular damage after OLT. Moreover, such studies will help to identify the timing of disease progression and damage, which in turn may help to prevent morbidity and mortality for cardiovascular diseases. Our preliminary results show early occurrence of atherosclerotic damage, which is already present a few weeks following OLT, suggesting that specific, patient-tailored therapies should be started immediately post OLT.

Subclinical cardiovascular changes in pediatric solid organ transplant recipients: A systematic review and meta-analysis

CV disease is a major cause of morbidity and mortality following solid organ transplantation in adults. While the prevalence of multiple cardiometabolic risk factors is increased in pediatric solid organ transplant recipients, it is not clear whether they have subclinical CV changes. cIMT, central pWV, and CAC are indicative of subclinical CV disease, and, in adults, predict future CV events. The objective of this systematic review and meta-analysis was to investigate the prevalence of subclinical CV changes, as measured by cIMT, pWV, and CAC among pediatric solid organ transplant recipients. We searched MEDLINE(®) and EMBASE and conducted meta-analysis for studies that evaluated cIMT, central pWV, and CAC among pediatric solid organ transplant recipients (kidney, lung, intestine and liver). The search identified nine eligible studies that included a total of 259 patients and 685 healthy controls. Eight studies reported on kidney transplant recipients and one study on a combined cohort of kidney and liver transplant recipients. The mean cIMT of transplant recipients was significantly higher than that of healthy controls (mean difference = 0.05 mm, 95% CI 0.02-0.07; p < 0.0001) with an estimated pooled prevalence of elevated cIMT of 56.0% (95% CI 17.0-95.0). The one study that assessed pWV showed increased vascular stiffness in transplant recipients compared to healthy controls. No studies assessing for CAC were found. There were limited data regarding subclinical CV disease following pediatric solid organ transplantation. In conclusion, kidney transplantation in childhood is associated with a higher prevalence of subclinical CV changes compared to healthy children. Longitudinal studies are needed to determine whether children have increased CV morbidity and mortality after transplantation.

Pediatric Origins of Nephrolithiasis-Associated Atherosclerosis

OBJECTIVES

To determine if nephrolithiasis-associated atherosclerosis has pediatric origins and to consider possible association between kidney stones and atherosclerosis-related proteins.

STUDY DESIGN

We matched children aged 12-17 years with kidney stones and without kidney stones. Carotid artery intima-media thickness (cIMT) was measured by ultrasound. Participants' urine was investigated by enzyme-linked immunosorbent assay for the atherosclerosis-related proteins fibronectin 1, macrophage scavenger receptor 1, osteopontin, and vascular cell adhesion molecule 1 levels, and normalized to urine creatinine levels.

RESULTS

Subjects with nephrolithiasis had higher cIMT in the right common carotid artery and overall mean measurement. Urine osteopontin and fibronectin 1 were significant predictors of cIMT.

CONCLUSIONS

We have provided initial preliminary evidence that nephrolithiasis-associated atherosclerosis has pediatric origins and performed studies that begin to identify potential reasons for the association of nephrolithiasis and vascular disease.

Cardiovascular risk 10 years after liver transplant

OBJECTIVES

We sought to evaluate the frequency of cardiovascular risk factors in a cohort of patients 10 years after a liver transplant, and to assess their 10-year risk of fatal cardiovascular disease using Systematic COronary Risk Evaluation (SCORE) charts.

MATERIALS AND METHODS

Between January 1990 and June 1996, one hundred eighty-nine adults underwent a first liver transplant in our center. Fifty-nine patients (31%) died before reaching their tenth year, and 115 patients were available with complete clinical data at 10 years.

RESULTS

The main indications for liver transplant were alcoholic (38%) and viral cirrhosis (40%). The median age of patients was 56 (range, 29-73 y), 80% were men, 23% were obese, 16% were active smokers, 18% were diabetic, 40% had hypercholesterolemia, and 77% had hypertension. Before the tenth year after transplant, 6 deaths were because of cardiovascular diseases, which represents the third cause of late death (> 1 year after liver transplant). After liver transplant, 5% of the surviving patients underwent ischemic cardiovascular events during the first decade. At a 10-year assessment, the median estimated 10-year risk of fatal cardiovascular disease was 1% (range, 0%-9%) and 10% of the patients had a high risk (ie, SCORE ≥ 5%).

CONCLUSIONS

Our results suggest that the frequency of cardiovascular events is relatively low after a liver transplant, even if most of the patients had 1 or more cardiovascular risk factors. Nevertheless, clinicians should perform a similar evaluation 15 or 20 years after the liver transplant because cardiovascular risk exponentially increases with age.

Cardiovascular disease in children with chronic kidney disease

More than a decade ago, cardiovascular disease (CVD) was recognized as a major cause of death in children with advanced CKD. This observation has sparked the publication of multiple studies assessing cardiovascular risk, mechanisms of disease, and early markers of CVD in this population. Similar to adults, children with CKD have an extremely high prevalence of traditional and uremia-related CVD risk factors. Early markers of cardiomyopathy, such as left ventricular hypertrophy and dysfunction, and early markers of atherosclerosis, such as increased carotid artery intima-media thickness, carotid arterial wall stiffness, and coronary artery calcification, are frequently present in these children, especially those on maintenance dialysis. As a population without preexisting symptomatic cardiac disease, children with CKD potentially receive significant benefit from aggressive attempts to prevent and treat CVD. Early CKD, before needing dialysis, is the optimal time to both identify modifiable risk factors and intervene in an effort to avert future CVD. Slowing the progression of CKD, avoiding long-term dialysis and, if possible, conducting preemptive transplantation may represent the best strategies to decrease the risk of premature cardiac disease and death in children with CKD.

Dysregulated gene expression of extracellular matrix and adhesion molecules in saphenous vein conduits of hemodialysis patients

OBJECTIVE

The incidence of cardiovascular disease was approximately 10 times higher in hemodialysis patients with end-stage renal disease than in the general population. The saphenous vein is the most commonly used conduit for coronary artery bypass grafting. However, the extracellular matrix and adhesion molecule characteristics of saphenous vein in hemodialysis patients remain unclear. The aim of the present study was to survey the extracellular matrix gene expression profile of the saphenous vein in hemodialysis patients undergoing coronary artery bypass grafting.

METHODS

A total of 34 patients undergoing elective coronary artery bypass grafting were enrolled. Of the 34 patients, 15 with end-stage renal disease required maintenance hemodialysis. The control group consisted of the other 19 patients without preoperative renal disease. Samples of the saphenous vein were obtained at coronary artery bypass grafting. The expression profile of the extracellular matrix genes was analyzed by microarray. The tissue matrix metallopeptidase/tissue inhibitor of metallopeptidase protein activities in the saphenous vein were evaluated by immunocytochemistry and Western blotting.

RESULTS

Nineteen extracellular matrix and adhesion molecule-focused genes demonstrated at least a threefold difference in expression between the 2 groups. Upregulation was observed in 16 genes, and 3 genes appeared to be downregulated. Notable imbalanced matrix metallopeptidase/tissue inhibitor of metallopeptidase protein activities of saphenous vein exposed to end-stage renal disease conditions was found.

CONCLUSIONS

The results from present study suggest that the native extracellular matrix gene expression profile of the saphenous vein conduits in hemodialysis patients show signs of the vein graft disease process before coronary surgery. Furthermore, some preoperative profiles of hemodialysis patients undergoing coronary artery bypass grafting might provide some useful clues regarding vein graft quality and prompt adjustment in surgical strategy.

Hypertension and CKD

Hypertension is found in more than 50% of pediatric patients with CKD. However, its prevalence varies according to the cause of CKD. It is relatively infrequent in children with structural disorders. Acquired renal disorders are associated with an increased prevalence of hypertension, similar to that of adults. Recent studies using ambulatory blood pressure monitoring indicate that children with CKD also have a high prevalence of masked hypertension. Similar to adults, long-standing and uncontrolled hypertension in children is associated with the progression of CKD and development of end-organ damage including early cardiomyopathy and premature atherosclerosis. Aggressive treatment of hypertension should be an essential part of pediatric CKD care, not just to prevent the development of symptomatic cardiovascular disease but also to delay progression of CKD. Recent findings from the European Effect of Strict Blood Pressure Control and ACE Inhibition on Progression of Chronic Renal Failure in Pediatric Patients (ESCAPE) trial have shown that the aggressive treatment of blood pressure, to below the 50th percentile, has even greater benefit in children with CKD, unlike results seen in adult studies.

Carotid intima-media thickness in children with end-stage renal disease on dialysis

Cardiovascular morbidity and mortality are common in end stage renal disease (ESRD) patients. There is scarce data on carotid and bulb intima-media thickness (IMT-C and IMT-B) as an early marker of atherosclerosis and related factors in children on hemodialysis (HD) and peritoneal dialysis (PD). Since we did not have enough information about our patients, this study was carried on all ESRD children (hemodialysis and peritoneal dialysis) in a referral center. Data was collected from 16 ESRD children under 18 years with seven patients on PD and nine on HD. Lab tests and biochemical parameters including serum von Willebrand factor (vWF), homocystein, apo lipoprotein A, apo lipoprotein B and quantitative CRP were measured in fasting patients just before initiating dialysis. IMT-C and IMT-B were measured by gray scale ultrasound using 7.5 MHZ probe. The mean of age was 12.76±4.5 years. The mean duration of dialysis in HD and PD patients were not significantly different; 11.88±3.25 months and 10.14±2.4 months respectively. Mean of systolic blood pressure in HD group was significantly higher than PD group, 135.55±25.54 mmHg versus 121.42±12.14 mmHg, P<0.05. Significant differences among all following parameters in ESRD patients, with normal laboratory values, were clarified: cholesterol, triglycerides, apo A, apo B, quantitative CRP, VWF, homocystein and IMT-C. However, we could not demonstrate any difference between IMT-B in case and control group. After adjusting for age, partial correlation showed significant correlation between IMT-C and following factors: N-PTH and serum alkaline phosphatase. Longitudinal studies with large size samples are needed to clarify the contributing factors with intima-media thickness in ESRD children.

Increased intima-media thickness of the carotid artery in childhood: a systematic review of observational studies

Increased carotid intima-media thickness (cIMT) in adults may be caused by a childhood exposure to cardiovascular risk factors. We systematically reviewed observational studies to determine whether obesity, insulin-dependent diabetes mellitus (IDDM), dyslipidemia (DL), hypertension (HT), and chronic renal failure (CRF) are associated with increased cIMT in children and adolescent patients compared with control subjects. We performed a PubMed literature search from January 1986 to February 2010. Two reviewers separately verified the inclusion criteria of relevant studies for the objective of the review. The data extracted in the patient and control groups were sample size, age, gender, cIMT measurement methods, cIMT values, and statistical analysis results. From 348 citations, 65 cross-sectional studies (2 cited twice) with case-control design met the inclusion criteria: 26 in obesity, 14 in IDDM, 11 in DL, 8 in HT, and 8 in CRF. cIMT measurement protocols varied according to the studies, with measurements being performed on the common carotid artery in 65/67 cases and on the far wall in 57/67 cases. From the 67 studies cited, 22/26 reported a significantly increased cIMT in obese children and adolescents compared with the control group, 8/14 in IDDM patients, 10/11 in DL patients, 7/8 in HT patients, and 8/8 in CRF patients.

CONCLUSION

Despite the heterogeneity of ultrasound measurement methods, cIMT was significantly increased in 55 out of the 67 cited studies, confirming early vascular damages in pediatric populations with an increased future risk for vascular diseases.

Outcomes in pediatric solid-organ transplantation

LaR Pediatric solid-organ transplantation is an increasingly successful treatment for organ failure. Five- and 10-yr patient survival rates have dramatically improved over the last couple of decades, and currently, over 80% of pediatric patients survive into adolescence and young adulthood. Waiting list mortality has been a concern for liver, heart, and intestinal transplantation, illustrating the importance of transplant as a life-saving therapy. Unfortunately, the success of pediatric transplantation comes at the cost of long-term or late complications that arise as a result of allograft rejection or injury, immunosuppression-related morbidity, or both. As transplant recipients enter adolescence treatment, non-adherence becomes a significant issue, and the medical and psychosocial impacts transition to adulthood not only with regard to healthcare but also in terms of functional outcomes, economic potential, and overall QoL. This review addresses the clinical and psychosocial challenges encountered by pediatric transplant recipients in the current era. A better understanding of pediatric transplant outcomes and adult morbidity and mortality requires further ongoing assessment.

CKD-MBD after kidney transplantation

Successful kidney transplantation corrects many of the metabolic abnormalities associated with chronic kidney disease (CKD); however, skeletal and cardiovascular morbidity remain prevalent in pediatric kidney transplant recipients and current recommendations from the Kidney Disease Improving Global Outcomes (KDIGO) working group suggest that bone disease-including turnover, mineralization, volume, linear growth, and strength-as well as cardiovascular disease be evaluated in all patients with CKD. Although few studies have examined bone histology after renal transplantation, current data suggest that bone turnover and mineralization are altered in the majority of patients and that biochemical parameters are poor predictors of bone histology in this population. Dual energy X-ray absorptiometry (DXA) scanning, although widely performed, has significant limitations in the pediatric transplant population and values have not been shown to correlate with fracture risk; thus, DXA is not recommended as a tool for the assessment of bone density. Newer imaging techniques, including computed tomography (quantitative CT (QCT), peripheral QCT (pQCT), high resolution pQCT (HR-pQCT) and magnetic resonance imaging (MRI)), which provide volumetric assessments of bone density and are able to discriminate bone microarchitecture, show promise in the assessment of bone strength; however, future studies are needed to define the value of these techniques in the diagnosis and treatment of renal osteodystrophy in pediatric renal transplant recipients.

Carotid intima-media thickness after pediatric renal or liver transplantation at high-resolution B-mode ultrasonography

In a previous study, we observed a higher incidence of dyslipidemia in pediatric renal recipients compared with liver recipients. In the present study, we measured common carotid artery intima-media thickness (IMT) in 13 pediatric renal recipients, 9 liver recipients, and 26 control individuals with median age of 11.4, 10.8, and 12.0 years, respectively. The patients were studied from 0.2 to 10.8 years after renal transplantation (RTx) or liver transplantation (LTx). An experienced radiologist (T.K.) blinded to the status of the children measured the IMT using a high-resolution B-mode ultrasonography method. In patients who underwent RTx or LTx, serum fasting lipid profile, estimates of renal and liver function, and glucose metabolism were determined. Children undergoing RTx or LTx more often had hypertension compared with the control individuals (P = .004). Before transplantation, dyslipidemia was greater in patients undergoing RTx compared with those undergoing LTx (P < .05). Children who underwent RTx, compared with those who underwent LTx or control individuals, had thicker mean IMT at the 6 sites measured (mean [SD], 0.57 [0.07], 0.51 [0.05], and 0.53 [0.06] mm, respectively; P = .02]. As a result of linear regression in renal recipients, variability of glomerular filtration rate (<60 mL/min/1.73 m(2) vs normal) accounted for 43.3% of variability of the mean of maximal IMT (B = 8.9; SE = 3.1; P = .01). Variability of pre-RTx serum triglyceride concentration (B = 1.6; SE = 0.6; P = .03) and actual triglyceride concentration (B = 10.3; SE = 2.2; P = .002) accounted for 82.2% of variability of maximal IMT. Our findings support previous data on the importance of maintenance of good graft function with sufficient but not overly efficient immunosuppression after transplantation in prevention of future cardiovascular disease.

Correlation between cathepsin D serum concentration and carotid intima-media thickness in hemodialysis patients

AIM

Cardiovascular (CV) disease is the leading cause of death in hemodialysis (HD) patients, and approximately half of mortalities in HD patients are attributed to CV disease. Atherosclerosis is the most frequent cause of CV complications in patients with end-stage renal disease (ESRD). Based on recent studies, cathepsin D has been suggested as a potential marker of atherosclerosis, and we hypothesized that there is an association between serum concentration of cathepsin D and carotid intima-media thickness (CIMT) in hemodialysis patients.

METHODS

Thirty-one hemodialysis patients (18 men and 13 women) were enrolled in this study. Serum levels of soluble cathepsin D were measured with an enzyme-linked immunosorbant assay (ELISA) kit. CIMT was determined in each patient.

RESULTS

The data showed that there was a positive significant correlation between serum concentration of cathepsin D and CIMT by using Pearson correlation (P value <0.05).

CONCLUSION

Based on the results of this study, cathepsin D could be suggested to have a role in the development of atherosclerotic plaques.

Cardiovascular disease in CKD in children: update on risk factors, risk assessment, and management

In young adults with onset of chronic kidney disease in childhood, cardiovascular disease is the most common cause of death. The likely reason for increased cardiovascular disease in these patients is a high prevalence of traditional and uremia-related cardiovascular disease risk factors during childhood chronic kidney disease. Early markers of cardiomyopathy, such as left ventricular hypertrophy and left ventricular dysfunction, and early markers of atherosclerosis, such as increased carotid artery intima-media thickness, carotid arterial wall stiffness, and coronary artery calcification, frequently are found in this patient population. The purpose of this review is to provide an update of recent advances in the understanding and management of cardiovascular disease risks in this population.