Post-transplant diabetes mellitus in children following renal transplantation

Monitoring of blood glucose after pediatric kidney transplantation: a longitudinal cohort study

BACKGROUND

Glucose metabolism after kidney transplantation (KT) is highly dynamic with the first post-transplantation year being the most critical period for new-onset diabetes after transplantation (NODAT) occurrence. The present study aimed to analyze dynamics of glucose metabolism and report incidence/risk factors of abnormal glycemic state during the first year after KT in children.

METHODS

Twenty-one consecutive freshly transplanted pediatric kidney transplant recipients (KTRs) were assessed for fasting plasma glucose (FPG) and oral glucose tolerance test (OGTT) weekly for 4 weeks, then every 3 months for 1 year.

RESULTS

Interpretation of OGTT test showed normal glucose tolerance (NGT) in 6 patients (28.6%) while 15 (71.4%) experienced impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT) at any time point of monitoring. Seven patients had NODAT, for which three needed insulin therapy. Hyperglycemia onset was 7.8 ± 13.12 weeks (median (range) = 1 (0-24) week) after KT. Percent of patients with abnormal OGTT was significantly more than that of IFG (38.1% vs. 71.4%, p = 0.029). Patients with abnormal glycemic state had significantly elevated trough tacrolimus levels at 6 months (p = 0.03). Glucose readings did not correlate with steroid doses nor rejection episodes while positively correlating with tacrolimus doses at 3 months (p = 0.02, CC = 0.73) and 6 months (p = 0.01, CC = 0.63), and negatively correlating with simultaneous GFR at 9 months (p = 0.04, CC =  - 0.57).

CONCLUSIONS

Up to two thirds of pediatric KTRs (71.4%) experienced abnormal glycemic state at some point with peak incidence within the first week up to 6 months after KT. OGTT was a better tool for monitoring of glucose metabolism than FPG. Abnormal glycemic state was induced by tacrolimus and adversely affected graft function. A higher resolution version of the Graphical abstract is available as Supplementary information.

Post-Transplantation Diabetes Mellitus in Pediatric Patients

More than 80% of pediatric solid organ transplant (SOT) recipients now survive into young adulthood and many encounter transplant-related complications. Post-transplantation diabetes mellitus (PTDM), sometimes also referred to as post-transplant diabetes or new onset diabetes after transplant, occurs in 3-20% of pediatric SOT recipients depending upon the organ transplanted, age at transplantation, immunosuppressive regimen, family history, and time elapsed since transplant. To diagnose PTDM, hyperglycemia must persist beyond the initial hospitalization for transplantation when a patient is on stable doses of immunosuppressive medications. Though standard diagnostic criteria used by the American Diabetes Association (ADA) to diagnose diabetes are employed, clinicians need to be aware of the limitations of using these criteria in this unique patient population. Management of PTDM parallels strategies used for type 2 diabetes (T2D), while also carefully considering comorbidities and potential interactions with immunosuppressive medications in these patients. In caring for patients with PTDM, it is important to be familiar with these interactions and comorbidities in order to coordinate care with the transplant team and optimize outcomes for these patients.

Pediatric Hand Transplantation: A Decision Analysis

Background: The first successful bilateral pediatric hand transplant was performed in 2015. Previous hand transplant decision analysis models have focused on the adult population. This model principally aimed to determine whether adverse outcomes associated with immunosuppression outweigh the benefits of performing bilateral hand transplant surgery in a pediatric candidate. The model also conceptualized the valuation of losing years of life and sought to determine the impact of that valuation on the surgical decision. Methods: A decision model compared undergoing bilateral hand transplant surgery with using prosthetics for an 8-year-old patient. The outcome measure used was quality adjusted life years (QALYs), and sensitivity analysis was performed on the immunosuppressive risks associated with the surgical decision, as well as the perceived valuation of aversion to life years lost. Results: The decision to perform surgery was marginally optimal compared to the prosthetic decision (50.11 QALY vs. 47.95 QALY). A Monte Carlo simulation revealed that this difference may be too marginal to detect an optimal decision (50.14 ± 8.28 QALY vs. 47.95 ± 2.12 QALY). Sensitivity analysis identified decision thresholds related to immunosuppression risks (P = 29% vs. P = 33% modeled), and a trend of increasing risk as a patient is more averse to losing life years. Conclusions: The marginally optimal treatment strategy currently is bilateral hand transplant, compared to prosthetics for pediatric patients. Key determinants of the future optimal strategy will be whether immunosuppressive regimens become safer, with a reduced risk of losing life years due to immunosuppressive complications, and whether prosthetics become more acceptable and enable higher functioning.

Post-transplant complications, patient, and graft survival in pediatric and adolescent kidney transplant recipients at a tropical tertiary care center across two immunosuppression eras

BACKGROUND

We report pediatric PAKT patient and graft outcomes at a large tropical tertiary center spanning two transplant eras.

METHODS

In this retrospective cohort study, all children ≤18 years who underwent kidney transplantation at our center between 1991 and 2016 were included. Data pertaining to their baseline characteristics, post-transplant events, and outcome were retrieved from transplant records and compared between transplant eras (1991-2005 and 2006-2016).

RESULTS

A total of 139 children (mean age 15.2 ± 2.9 years) underwent PAKT during this period. The incidence of UTIs, CMV disease, BKVN, invasive fungal infections, new-onset diabetes after transplant, leucopenia, and recurrent NKD was higher in the 2006-2016 era (P < .001 for all), while 1-year cumulative BPAR was comparable (P = .100). Five-year graft and patient survival in the two eras were 89.9% and 94.2% (P = .365) and 92.1% and 95.3% (P = .739), respectively. Incidence of CMV disease, BKVN, graft loss, and death was lower in the calcineurin withdrawal group. Non-adherence accounted for 36% of graft loss; infections caused 43.7% of deaths. On multivariate Cox proportional hazards analysis, independent predictors for graft loss were UTIs and blood transfusion naïve status and for death were serious infections and glomerular NKD.

CONCLUSIONS

PAKT in India has excellent long-term graft outcomes, though patient outcomes remain suboptimal owing to a high burden of infections. Current immunosuppression protocols need to be re-examined to balance infection risk, graft, and patient survival.

Risk Factors for Developing Posttransplant Diabetes After Pediatric Kidney Transplant in a Canadian Tertiary Care Children's Hospital Between 1995 and 2016

BACKGROUND

Posttransplant diabetes mellitus (PTDM) is a serious complication in kidney transplant recipients (KTRs) due to its negative impact on graft and patient survival. Although reported in 3% to 20% of pediatric KTRs, it has not been as well characterized in adults. In this study we describe incidence and risk factors associated with development of PTDM in pediatric KTRs.

METHODS

This work is a retrospective cohort study of nondiabetic pediatric patients, aged 6 months to 19 years, who underwent a first kidney transplant during 1995 to 2016. We estimated the cumulative incidence rate and used multivariable logistic regression to identify the diabetogenic risk factors for PTDM.

RESULTS

A total of 142 KTRs were included in this study. The cumulative incidence of PTDM was 31% and 14.1% in the first and second year posttransplant, respectively. Significant risk factors for PTDM in the first year after transplant included: dysglycemia in the first 8 to 30 days posttransplant (adjusted odds ratio [aOR], 3.02; 95% confidence interval [CI], 1.21 to 7.53; p=0.018) and use of sirolimus in the first 30 days posttransplant (aOR, 5.33; 95% CI, 1.16 to 24.35; p=0.031). No significant association was found with typical diabetogenic factors.

CONCLUSIONS

The incidence of PTDM is high among pediatric KTRs. Independent risk factors associated with PTDM included meeting the criteria for dysglycemia or diabetes and sirolimus use in the first month posttransplant. Typical diabetogenic risk factors for type 2 diabetes were not associated with increased risk. This study provides valuable information for posttransplant medical care and future research.

Oral Glucocorticoids and Incident Treatment of Diabetes Mellitus, Hypertension, and Venous Thromboembolism in Children

Rates of incident treatment were quantified in this study for diabetes mellitus, hypertension, and venous thromboembolism (VTE) associated with oral glucocorticoid exposure in children aged 1-18 years. The retrospective cohort included more than 930,000 children diagnosed with autoimmune diseases (namely, inflammatory bowel disease, juvenile idiopathic arthritis, or psoriasis) or a nonimmune comparator condition (attention-deficit/hyperactivity disorder) identified using US Medicaid claims (2000-2010). Associations of glucocorticoid dose per age- and sex-imputed weight with incident treated diabetes, hypertension, and VTE were estimated using Cox regression models. Crude rates were lowest for VTE (unexposed: 0.5/million person-days (95% confidence interval (CI): 0.4, 0.6); currently exposed: 15.6/million person-days (95% CI: 11.8, 20.1)) and highest for hypertension (unexposed: 6.7/million person-days (95% CI: 6.5, 7.0); currently exposed: 74.4/million person-days (95% CI: 65.7, 83.9)). Absolute rates for all outcomes were higher in unexposed and exposed children with autoimmune diseases compared with those with attention-deficit/hyperactivity disorder. Strong dose-dependent relationships were found between current glucocorticoid exposure and all outcomes (adjusted hazard ratios for high-dose glucocorticoids: for diabetes mellitus, 5.93 (95% CI: 3.94, 8.91); for hypertension, 19.13 (95% CI: 15.43, 23.73); for VTE, 16.16 (95% CI: 8.94, 29.22)). These results suggest strong relative risks, but low absolute risks, of newly treated VTE, diabetes, and especially hypertension in children taking high-dose oral glucocorticoids.

Glucose tolerance in a cohort of Egyptian children after kidney transplantation

BACKGROUND

Post- transplantation diabetes mellitus (PTDM) in children is a serious metabolic complication that can endanger both graft and patient survival. These complications can be partially reduced by early diagnosis & prompt treatment of impaired glucose tolerance. The aim of this study was to assess glucose tolerance & insulin resistance among a cohort of kidney transplanted children.

METHODS

Thirty consecutive pediatric kidney transplant recipients were subjected to basal evaluation of plasma glucose and insulin then underwent oral glucose tolerance test (OGTT).

RESULTS

Abnormal glucose metabolism was detected in 7 (23.3%) patients; 3 (10%) patients with PTDM; 3 (10%) patients with impaired fasting glucose (IFG) and 1 (3.3%) patient with IFG and impaired glucose tolerance (IGT). Four (13.3%) patients had high Homeostatic model assessment of insulin resistance (HOMA-IR). Patients with abnormal glucose metabolism had significantly higher tacrolimus trough levels and higher maintainence steroid doses (p values = 0.003,0.026). Significant positive correlation existed between pre-transplantation glucose level and post-transplantation fasting glucose (p = 0.001, r = 0.69), glucose at 120 min (p = 0.018, r = 0.429) and HOMA-IR (p = 0.008, r = 0.47).

CONCLUSION

Abnormalities in glucose metabolism (IFG, IGT &PTDM) are frequent in Egyptian pediatric kidney transplant recipients. OGTT is the gold standard for assessment of abnormalities in glucose metabolism.

Incidence of new-onset diabetes mellitus and association with mortality in childhood solid organ transplant recipients: a population-based study

BACKGROUND

Precise estimates of the long-term risk of new-onset diabetes and its impact on mortality among transplanted children are not known.

METHODS

We conducted a cohort study comparing children undergoing solid organ (kidney, heart, liver, lung and multiple organ) transplant (n = 1020) between 1991 and 2014 with healthy non-transplanted children (n = 7 134 067) using Ontario health administrative data. Outcomes included incidence of diabetes among transplanted and non-transplanted children, the relative hazard of diabetes among solid organ transplant recipients, overall and at specific intervals posttransplant, and mortality among diabetic transplant recipients.

RESULTS

During 56 019 824 person-years of follow-up, the incidence rate of diabetes was 17.8 [95% confidence interval (CI) 15-21] and 2.5 (95% CI 2.5-2.5) per 1000 person-years among transplanted and non-transplanted children, respectively. The transplant cohort had a 9-fold [hazard ratio (HR) 8.9; 95% CI 7.5-10.5] higher hazard of diabetes compared with those not transplanted. Risk was highest within the first year after transplant (HR 20.7; 95% CI 15.9-27.1), and remained elevated even at 5 and 10 years of follow-up. Lung and multiple organ recipients had a 5-fold (HR 5.4; 95% CI 3.0-9.8) higher hazard of developing diabetes compared with kidney transplant recipients. Transplant recipients with diabetes had a three times higher hazard of death compared with those who did not develop diabetes (HR 3.3; 95% CI 2.3-4.8).

CONCLUSIONS

The elevated risk of diabetes in transplant recipients persists even after a decade, highlighting the importance of ongoing surveillance. Diabetes after transplantation increases the risk of mortality among childhood transplant recipients.

Diabetes Type 2 in Neurologically Impaired Children and Adolescents Without Obesity: A New Emerging Entity?

Background: Insulin resistance (IR) plays a key role in the pathogenesis of type 2 diabetes (T2D). In neurologically impaired (NI) children unfavorable cardio-metabolic risk profile with high prevalence of IR has been reported. We evaluated the prevalence of T2D in NI children and adolescents, in order to define if a dedicated glucose monitoring may be recommended in these subjects.

Methods: We retrospectively evaluated 63 patients (11.4 ± 4.0 years) with severe disabilities. Auxological parameters were recorded. Metabolic blood assays included fasting blood glucose (FBG), fasting insulin, triglycerides (TG). IR was detected with the homeostasis model assessment for insulin resistance (HOMA-IR > 97.5th percentile for age and sex) and triglyceride-glucose index (TyG index > 7.88). Elevated FBG was defined with values >100 mg/dl. T2D was defined according to American Diabetes Association criteria.

Results: Impaired insulin sensitivity, pathological TyG index and elevated FBG were observed, respectively, in 41.3, 63.5, and 11.1% patients. T2D was diagnosed in 3.2% asymptomatic patients. The prevalence of diabetes was higher in pre-pubertal compared to pubertal subjects (p = 0.03).

Conclusions: T2D in NI children and adolescents without obesity could represent a new emerging entity. IR and/or surrogate markers of IR index may be useful for the primary screening of this at-risk disabled population so as to prevent diabetes.

Long-Term Outcomes of Kidney Transplantation in Children

Kidney transplantation is the preferred treatment for end-stage renal disease (ESRD) in children and confers improved survival, skeletal growth, heath-related quality of life, and neuropsychological development compared with dialysis. Kidney transplantation in children with ESRD results in 10-year patient survival exceeding 90%. Therefore, the long-term management of these patients is focused on maintaining quality of life and minimizing long-term side effects of immunosuppression. Optimal management of pediatric kidney transplant recipients includes preventing rejection and infection, identifying and reducing the cardiovascular and metabolic effects of long-term immunosuppressive therapy, supporting normal growth and development, and managing a smooth transition into adulthood.

Diabetes mellitus in pediatric solid organ recipients without and with cystic fibrosis: An analysis from the German-Austrian diabetes database (Diabetes Patienten Verlaufsdokumentation)

INTRODUCTION

Posttransplantation diabetes mellitus (PTDM) increases the risk of cardiovascular disease, graft loss, and decreased survival. Follow-up treatment after solid organ transplantation (SOT) needs to focus on, inter alia, maintaining balanced glucose metabolism. This study aimed to ascertain the prevalence of PTDM and describe patient characteristics in the large DPV (Diabetes Patienten Verlaufsdokumentation) pediatric diabetes database.

METHODS

DPV data of 71 902 patients from the January 01, 1995 to January 04, 2015 period were analyzed for patients with and without cystic fibrosis (CF) after SOT (kidney, liver, heart, and lung). Multivariable analysis served to assess differences between SOT patient groups at risk for developing diabetes.

RESULTS

Out of 109 SOT patients, 51 had CF; 72.5% received steroids and 62% were additionally given tacrolimus. PTDM developed in 45% of CF patients and 12% of non-CF patients. SOT patients were older at diabetes onset (mean age, 12.50 ± 3.98 years), shorter (height z-score, -1.67 ± 1.25), and lighter (weight z-score, -1.59 ± 1.57) than non-SOT diabetes patients (P < 0.01). With transplantation, glycated hemoglobin (HbA1c) was significantly lower and treatment for hypertension and dyslipidemia was increased. Among SOT patients, weight and body mass index (BMI) z-scores were significantly lower in patients with CF-related diabetes (P < 0.05).

CONCLUSIONS

SOT was present in 6.6% of children with diabetes, and this might aggravate the risk of cardiovascular disease in populations with already increased rates of hypertension and dyslipidemia. Dystrophy and short stature were also present, particularly in transplant recipients with CF and diabetes. Comorbidities and long-term consequences call for multidisciplinary collaboration.

Non-Diabetic Hyperglycemia in the Pediatric Age: Why, How, and When to Treat?

PURPOSE OF REVIEW

Non-diabetic hyperglycemia (NDHY) is a pathological condition that is not yet well known. The aim of this review is to examine approaches for management of this condition.

RECENT FINDINGS

While it is well known that persistent hyperglycemia in diabetes affects immune response and risk for diabetes-related micro- and macrovascular complications, little is known about the biological effects of transient NDHY, particularly in the pediatric age group. Stress HY (SHY) is typically defined as blood glucose > 8.33 mmol/L (150 mg/dL) during physical stress, resolving spontaneously after dissipation of acute illness in patients without known diabetes. Based on the literature and clinical practice, two situations can be classified: (1) SHY1, which occurs during severe and prolonged illness and under serious life-threatening conditions, mainly in emergency situations and in resuscitation areas; and (2) SHY2, which occurs during acute illness, mainly in non-life-threatening conditions. Furthermore, (NDHY) among pediatric patients can be induced by drugs; the most frequent conditions are secondary to (1) steroid therapy and (2) antineoplastic/immunosuppressive therapy.

Pharmacogenetics of post-transplant diabetes mellitus in children with renal transplantation treated with tacrolimus

BACKGROUND

Post-transplant diabetes mellitus (PTDM) is a major complication of immunosuppressive therapy, with many risk factors reported in adults with renal transplantation. The objective of this study was to investigate potential non-genetic and genetic risk factors of PTDM in children with renal transplantation treated with tacrolimus.

METHODS

A national database was screened for patients developing PTDM within 4 years following tacrolimus introduction. PTDM was defined as glucose disorder requiring anti-diabetic treatment. PTDM patients were matched to "non-PTDM" control transplanted children according to age, gender, and duration of post-transplant follow-up. Patients were genotyped for six selected genetic variants in POR*28 (rs1057868), PPARa (rs4253728), CYP3A5 (rs776746), VDR (rs2228570 and rs731236), and ABCB1 (rs1045642) genes, implicated in glucose homeostasis and tacrolimus disposition.

RESULTS

Among the 98 children with renal transplantation enrolled in this multicentre study, 18 developed PTDM. None of the clinical and biological parameters was significant between PTDM and control patients. Homozygous carriers of POR*28 or wild-type ABCB1 (rs1045642) gene variants were more frequent in PTDM than in control patients with differences close to significance (p = 0.114 and p = 0.066 respectively). A genetic score based on these variants demonstrated that POR*28/*28 and ABCB1 CC or CT genotype carriers were at a significantly higher risk of developing PTDM after renal transplantation.

CONCLUSION

Identification of PTDM risk factors should allow clinicians to allocate the best immunosuppressant for each patient with renal transplantation, and improve care for patients who are at a higher risk.

Incidence of hyperglycemia and diabetes and association with electrolyte abnormalities in pediatric solid organ transplant recipients

Background

Posttransplant hyperglycemia is an important predictor of new-onset diabetes after transplantation, and both are associated with significant morbidity and mortality. Precise estimates of posttransplant hyperglycemia and diabetes in children are unknown. Low magnesium and potassium levels may also lead to diabetes after transplantation, with limited evidence in children.

Methods

We conducted a cohort study of 451 pediatric solid organ transplant recipients to determine the incidence of hyperglycemia and diabetes, and the association of cations with both endpoints. Hyperglycemia was defined as random blood glucose levels ≥11.1 mmol/L on two occasions after 14 days of transplant not requiring further treatment. Diabetes was defined using the American Diabetes Association Criteria. For magnesium and potassium, time-fixed, time-varying and rolling average Cox proportional hazards models were fitted to evaluate the association with hyperglycemia and diabetes.

Results

Among 451 children, 67 (14.8%) developed hyperglycemia and 27 (6%) progressed to diabetes at a median of 52 days (interquartile range 22-422) from transplant. Multi-organ recipients had a 9-fold [hazard ratio (HR) 8.9; 95% confidence interval (CI) 3.2-25.2] and lung recipients had a 4.5-fold (HR 4.5; 95% CI 1.8-11.1) higher risk for hyperglycemia and diabetes, respectively, compared with kidney transplant recipients. Both magnesium and potassium had modest or no association with the development of hyperglycemia and diabetes.

Conclusions

Hyperglycemia and diabetes occur in 15 and 6% children, respectively, and develop early posttransplant with lung or multi-organ transplant recipients at the highest risk. Hypomagnesemia and hypokalemia do not confer significantly greater risk for hyperglycemia or diabetes in children.

Effects of acute rejection vs new-onset diabetes after transplant on transplant outcomes in pediatric kidney recipients: analysis of the Organ Procurement and Transplant Network/United Network for Organ Sharing (OPTN/UNOS) database

Improving long-term transplant and patient survival is still an ongoing challenge in kidney transplant medicine. Our objective was to identify the subsequent risks of new-onset diabetes after transplant (NODAT) and acute rejection (AR) in the first year post-transplant in predicting mortality and transplant failure. A total of 4687 patients without preexisting diabetes (age 2-20 years, 2004-2010) surviving with a functioning transplant for longer than 1 year with at least one follow-up report were identified from the OPTN/UNOS database as of September 2014. Study population was stratified into four mutually exclusive groups: Group 1, patients with a history of AR; Group 2, NODAT+; Group 3, NODAT+ AR+; and Group 4, the reference group (neither). Multivariate regression was used to analyze the relative risks for the outcomes of transplant failure and mortality. The median follow-up time was 1827 days after 1 year post-transplant. AR was associated with an increased risk of adjusted graft and death-censored graft failure (HR 2.87, CI 2.48-3.33, P < .001 and HR 2.11, CI 1.81-2.47, P < .001), respectively. NODAT and AR were identified in 3.5% and 14.5% of all study patients, respectively. AR in the first year post-transplant was a major risk factor for overall and death-censored graft failure, but not mortality. However, NODAT was not a risk factor on graft survival or mortality.

Renal transplantation in infants

Renal transplantation (RTx) has become an accepted mode of therapy in infants with severe renal failure. The major indications are structural abnormalities of the urinary tract, congenital nephrotic syndrome, polycystic diseases, and neonatal kidney injury. Assessment of these infants needs expertise and time as well as active treatment before RTx to ensure optimal growth and development, and to avoid complications that could lead to permanent neurological defects. RTx can be performed already in infants weighing around 5 kg, but most operations occur in infants with a weight of 10 kg or more. Perioperative management focuses on adequate perfusion of the allograft and avoidance of thrombotic and other surgical complications. Important long-term issues include rejections, infections, graft function, growth, bone health, metabolic problems, neurocognitive development, adherence to medication, pubertal maturation, and quality of life. The overall outcome of infant RTx has dramatically improved, with long-term patient and graft survivals of over 90 and 80 %, respectively.

Cystine accumulation attenuates insulin release from the pancreatic β-cell due to elevated oxidative stress and decreased ATP levels

The pancreatic β-cell has reduced antioxidant defences making it more susceptible to oxidative stress. In cystinosis, a lysosomal storage disorder, an altered redox state may contribute to cellular dysfunction. This rare disease is caused by an abnormal lysosomal cystine transporter, cystinosin, which causes excessive accumulation of cystine in the lysosome. Cystinosis associated kidney damage and dysfunction leads to the Fanconi syndrome and ultimately end-stage renal disease. Following kidney transplant, cystine accumulation in other organs including the pancreas leads to multi-organ dysfunction. In this study, a Ctns gene knockdown model of cystinosis was developed in the BRIN-BD11 rat clonal pancreatic β-cell line using Ctns-targeting siRNA. Additionally there was reduced cystinosin expression, while cell cystine levels were similarly elevated to the cystinotic state. Decreased levels of chronic (24 h) and acute (20 min) nutrient-stimulated insulin secretion were observed. This decrease may be due to depressed ATP generation particularly from glycolysis. Increased ATP production and the ATP/ADP ratio are essential for insulin secretion. Oxidised glutathione levels were augmented, resulting in a lower [glutathione/oxidised glutathione] redox potential. Additionally, the mitochondrial membrane potential was reduced, apoptosis levels were elevated, as were markers of oxidative stress, including reactive oxygen species, superoxide and hydrogen peroxide. Furthermore, the basal and activated phosphorylated forms of the redox-sensitive transcription factor NF-κB were increased in cells with silenced Ctns. From this study, the cystinotic-like pancreatic β-cell model demonstrated that the altered oxidative status of the cell, resulted in depressed mitochondrial function and pathways of ATP production, causing reduced nutrient-stimulated insulin secretion.

New-onset diabetes after kidney transplant in children

The development of new-onset diabetes after kidney transplantation (NODAT) is associated with reduced graft function, increased cardiovascular morbidity and lower patient survival among adult recipients. In the pediatric population, however, the few studies examining NODAT have yielded inconsistent results. Therefore, the true incidence of NODAT in the pediatric population has been difficult to establish. The identification of children and adolescents at risk for NODAT requires appropriate screening questions and tests pre- and post-kidney transplant. Several risk factors have been implicated in the pathogenesis of NODAT and post-transplant glucose intolerance, including African American race, obesity, family history of diabetes and the type of immunosuppressant regimen. Moreover, uremia per se results in a state of insulin resistance that increases the risk of developing diabetes post-transplant. When an individual becomes glucose intolerant, early lifestyle modification and antihyperglycemic measures with tailoring of the immunosuppressant regimen should be implemented to prevent the development of NODAT. For the child or adolescent with NODAT, antihyperglycemic therapy should be prescribed in order to achieve optimal glycemic control, ultimately reducing complications and improving overall allograft and patient survival. In this article, we review the risk factors, screening methods, diagnosis, management and outcome of children and adolescents with NODAT and post-kidney transplant glucose intolerance.

Type 2 diabetes presenting with hyperglycaemic hyperosmolar state in an adolescent renal transplant patient

Hyperglycaemic hyperosmolar state (HHS) is a life-threatening condition rarely seen in paediatrics. It is becoming increasingly recognised with the growing incidence of childhood type 2 diabetes mellitus (T2DM). We present a 16-year-old boy with Bardet-Biedl syndrome, with comorbidities including chronic renal impairment requiring renal transplant, isolated growth hormone (GH) deficiency and obesity, who presented on routine follow-up with new onset T2DM and in HHS. Investigations revealed hyperglycaemia (45.7 mmol/L), ketones of 0.1 mmol/L, pH 7.38 and osmolarity 311 mOsmol/kg. After acute management with fluid resuscitation and intravenous insulin, he is now stable on metformin. He has lost weight, renal function is stable and he has stopped GH therapy. We discuss the dilemmas encountered in his long-term management due to his renal transplant and comorbidities, and whether or not, given his significant T2DM risk, this case was preventable or predictable.

Four pediatric patients with autosomal recessive polycystic kidney disease developed new-onset diabetes after renal transplantation

NODAT is increasingly prevalent. Compared with adult recipients, NODAT is less prevalent in pediatric renal transplant recipients; however, some risk factors for its development in young patients have been defined. We report four pediatric renal transplant recipients with ARPKD who developed NODAT. We review the current pediatric NODAT literature and hypothesize that ARPKD may be an additional risk factor for NODAT.

Recent developments in kidney transplantation in children

PURPOSE OF REVIEW

Renal transplantation in childhood is a well established procedure with excellent short-term outcomes. However, waiting times for transplantation are still relatively long if living donation cannot be performed, and long-term outcomes after transplantation have not significantly improved during the last decade.

RECENT FINDINGS

This review describes alternative modalities to improve donation rates such as en bloc kidney transplantation from young donors, ABO-incompatible transplantation and kidney paired donation. This review also deals with long-term post-transplant morbidities, such as follows: first, medication side-effects (metabolic syndrome, cardiovascular disease) and with the benefits of steroid and calcineurin inhibitor drug minimization; second, the deleterious impact of viral infections and their management and third, chronic antibody-mediated rejection, its therapeutic and prevention possibilities.

SUMMARY

Donor shortage and long-term morbidities, after transplantation, are still relevant issues in paediatric renal transplantation medicine. Significant research and efforts have been made to advance the field and create novel approaches for improvement of transplantation rates and post-transplant graft or patient survival. These modalities are to be established in the routine setting.

Metabolic risk factors and long-term graft function after paediatric renal transplantation

The aim of this study was to evaluate metabolic risk factors and their impact on long-term allograft function in paediatric renal transplant (RTx) patients. We reviewed the medical records of 210 RTx patients who underwent transplantation at a median age of 4.5 years (range 0.7-18.2) and a median follow-up of 7.0 years (range 1.5-18.0). Data on lipid and glucose metabolism, uric acid levels, weight and blood pressure were collected up to 13 years post-RTx, and the findings were correlated with the measured glomerular filtration rate (GFR). Beyond the first year, GFR showed gradual deterioration with a mean decline of 2.4 ml/min/1.73 m(2)/year. Metabolic syndrome, overweight, hypertension and type 2 diabetes were diagnosed in 14-19%, 20-23%, 62-87% and 3-5% of the patients, respectively. These entities showed only mild association with the concomitant or long-term GFR values. Dyslipidaemia was common and hypertriglyceridaemia associated with a lower GFR at 1.5 and 5 years post-RTx (P = 0.008 and P = 0.017, respectively). Similarly, hyperuricaemia was frequent and associated significantly with GFR (P < 0.001). Except for hyperuricaemia and hypertriglyceridaemia, metabolic risk factors beyond the first postoperative year associated modestly with the long-term kidney graft function in paediatric RTx patients.

Left ventricular diastolic dysfunction by tissue Doppler echocardiography in pediatric chronic kidney disease

BACKGROUND

Myocardial dysfunction is common in chronic kidney disease (CKD) and related to poor outcomes. New non-invasive methods to assess cardiac function have been introduced, but comparative studies evaluating their clinical usefulness in pediatric CKD are lacking. We studied left ventricular (LV) function in pediatric CKD and renal transplant patients, comparing conventional pulse-wave Doppler echocardiography (cPWD) with newer tissue Doppler imaging (TDI) and relating the results to known cardiovascular risk factors.

METHODS

The study included 34 children/adolescents with CKD stages 2-5, 44 renal transplant patients and 19 patients with a normal renal function. The mean age was 11.4 (range 0.8-18.8) years.

RESULTS

Both patient groups had significantly lower LV diastolic function than those with a normal renal function. The most sensitive determinants were TDI E'/A' and cPWD E/TDI E' ratios. In a stepwise linear regression analysis, high blood pressure, young age and the presence of albuminuria all independently predicted LV diastolic function.

CONCLUSIONS

Our study confirms the high prevalence of LV diastolic dysfunction in pediatric CKD patients and following renal transplantation, where TDI appears to be more sensitive than cPWD in assessing early myocardial dysfunction. Our results also underline the importance of preventive measures, such as rigorous blood pressure control, in pediatric CKD.

Continuous glucose monitoring system (CGMS) in kidney-transplanted children

NODAT and IGT are well-known complications of immunosuppressive therapy after transplantation being a risk factor for cardiovascular disease affecting patient and graft survival. Therefore, early identification and treatment are of high importance. In this study, we examined the glycemic homeostasis of 20 renal-transplanted children using routine laboratory tests and the continuous glucose monitoring system (CGMS). Six patients (30%) had IGT, and one patient had NODAT (5%). The HOMA index was in an abnormal range in 35% of all patients and was abnormal in 67% of the IGT patients. CGMS analysis showed that IGT patients had higher "lowest glucose" level, and the incidence of hypoglycemic episodes was significantly lower compared with patients with normal OGTT result. In IGT patients, glucose variability tended to be lower. Furthermore, in the whole patient cohort, glucose variability significantly decreased with time after transplantation. Summarizing, these novel data show that "lowest glucose" level and hypoglycemic episodes are significantly influenced and altered in renal-transplanted patients with IGT. Furthermore, there is a decrease in glucose variability with time after transplantation. The mechanism and relevance of these data need further investigations.

Glucose intolerance: is it a risk factor for cardiovascular disease in children with chronic kidney disease?

A total of 66 children and adolescents with chronic kidney disease (CKD) (20 pre-dialysis patients and 46 chronic dialysis patients) were evaluated to address the prevalence of abnormalities in glucose and insulin metabolism and their association with cardiovascular disease. Glucose intolerance was assessed using an oral glucose tolerance test; insulin resistance was estimated by the homeostasis model assessment of insulin resistance (HOMA-IR). Carotid artery intima-media thickness (IMT) and left ventricular hypertrophy (LVH) were examined as early markers of cardiovascular disease. Thirty-four patients (7 pre-dialysis, 27 dialysis) exhibited an abnormal glucose tolerance; however, ten patients (7 pre-dialysis, 3 dialysis) were insulin-resistant. Height-specific standard deviation scores of carotid artery IMT were above normal in three of the pre-dialysis patients (15%) and in 34 of the dialysis patients (74%). LVH was present in seven pre-dialysis (35%) and 34 dialysis patients (74%). In addition, two of the pre-dialysis patients (10%) and 18 of the dialysis patients (39%) had severe LVH. The prevalence of both increased carotid artery IMT and LVH were similar in patients with or without glucose intolerance in both groups, but severe LVH was more prevalent in pre-dialysis patients with glucose intolerance (p = 0.042). The multivariate analyses showed that neither carotid artery IMT nor LVM index was predicted by serum glucose levels or HOMA-IR. In conclusion, children with CKD are at a high risk of glucose intolerance and also have a greater risk of subclinical cardiovascular disease (CVD). However, the presence of glucose intolerance does not appear to be an independent risk factor for increased carotid artery IMT or LVH.

The importance of different immunosuppressive regimens in the development of posttransplant diabetes mellitus

Solid-organ transplantation is the optimal long-term treatment for most patients with end-stage organ failure. After solid-organ transplantation, short-term graft survival significantly improved (1). However, due to chronic allograft nephropathy and death with functioning graft, long-term survival has not prolonged remarkably (2). Posttransplant immunosuppressive medications consist of one of the calcineurin inhibitors in combination with mycophenolate mofetil (MMF) or azathioprine (Aza) and steroids. All of them have different adverse effects, among which posttransplant diabetes mellitus (PTDM) is an independent risk factor for cardiovascular (CV) events and infections causing the death of many transplant patients and it may directly contribute to graft failure (3). According to the criteria of the American Diabetes Association (4), diabetes mellitus (DM) is defined by symptoms of diabetes (polyuria and polydipsia and weight loss) plus casual plasma glucose concentration ≥ 11.1 mmol/L or fasting plasma glucose (FPG) ≥ 7.0 mmol/L or 2-h plasma glucose level ≥ 11.1 mmol/L following oral glucose tolerance test (OGTT). This metabolic disorder occurring as a complication of organ transplantation has been recognized for many years. PTDM, which is a combination of decreased insulin secretion and increased insulin resistance, develops in 4.9/15.9% of liver transplant patients, in 4.7/11.5% of kidney recipients, and in 15/17.5% of heart and lung transplants [cyclosporine A (CyA)/tacrolimus (Tac)-based regimen, respectively] (5). Risk factors of PTDM can be divided into non-modifiable and modifiable ones (6), among which the most prominent is the immunosuppressive therapy being responsible for 74% of PTDM development (7). Emphasizing the importance of the PTDM, numerous studies have determined the long-term outcome. On the basis of these studies, graft and patient survival is tendentiously (8) or significantly (9, 10) decreased for those developing PTDM.

Solid-organ transplantation in childhood: transitioning to adult health care

Pediatric solid-organ transplantation is an increasingly successful treatment for solid-organ failure. With dramatic improvements in patient survival rates over the last several decades, there has been a corresponding emergence of complications attributable to pretransplant factors, transplantation itself, and the management of transplantation with effective immunosuppression. The predominant solid-organ transplantation sequelae are medical and psychosocial. These sequelae have a substantial effect on transition to adult care; as such, hurdles to successful transition of care arise from the patients, their families, and pediatric and adult health care providers. Crucial to successful transitioning is the ongoing development of a sense of autonomy and responsibility for one's own care. In this article we address the barriers to transitioning that occur with long-term survival in pediatric solid-organ transplantation. Although a particular transitioning model is not promoted, practical tools and strategies that contribute to successful transitioning of pediatric patients who have received a transplant are suggested.

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.

The synergistic effect of Tautomycetin on Cyclosporine A-mediated immunosuppression in a rodent islet allograft model

Most immunosuppressive drugs that support successful allograft survival act by inhibiting or depleting T lymphocytes. Tautomycetin (TMC) is a specific inhibitor of protein phosphatase 1, which has a role in cell-cycle control and T-cell activation and promotes T-cell-specific apoptosis. In this study, we investigated the effect on rat islet transplantation of TMC alone and in combination with cyclosporine A (CsA). TMC treatment inhibited splenocyte proliferation in mixed lymphocyte reactions (MLR) without affecting cell viability. When used alone in islet allograft recipients, TMC did not significantly increase the survival of grafted islets. However, cotreatment of TMC and subtherapeutic doses of CsA significantly prolonged islet graft survival from 5.1 d to more than 100 d (P<0.05). At 100 d, there was no evidence of specific organ toxicity, and histological analyses of grafted liver tissue revealed the presence of viable islets. CD4+ and CD8+ T-cell infiltration and interleukin (IL)-2 mRNA levels were decreased in TMC/CsA-cotreated rats, whereas IL-10 levels were increased. In addition, the number of FoxP3-expressing cells and FoxP3 mRNA levels were also increased. We suggest that CsA and TMC act synergistically to reduce the function of T-effector cells and enhance regulatory cell function in this islet allotransplantation model.

Investigation of impaired carbohydrate metabolism in pediatric liver transplant recipients

OGTT was performed in 28 liver transplants maintained with tacrolimus to investigate carbohydrate metabolism and assess risk factors for development of PTDM. None had PTDM that was detected by OGTT. Early PTDM in four cases (14.3%) resolved in follow-up. Five new cases (17.9%) demonstrated DCM (DCM = IGT +/- hyperinsulinemia). Fasting measurements were normal in two hyperinsulinemic cases. With one (20%, p > 0.05) exception none of the children with DCM were overweight or had a family history of diabetes. All five (100%) children with DCM had been given high cumulative dosage of steroids 18 (78.3%)--without DCM (p > 0.05). The median age of children with DCM was greater [4.3 (12.7-18.0) vs. 7.0 (2.3-18.0) yr, p < 0.01] and duration of follow-up longer [5.3 (2.3-7.0) vs. 2.5 (0.7-7.3) yr, p < 0.05]. Four children (80%) with DCM were pubertal (p < 0.05). However, neither age nor duration of follow-up or pubertal stage had significant effect on DCM development. Early PTDM is a transient phenomenon and is not predictive for future development of diabetes. DCM is frequently observed in liver transplanted children. Albeit the children with DCM were given high cumulative dose of steroids, were older, mostly were pubertal, and had longer duration of follow-up, we cannot draw firm conclusions on effects of the risk factors on carbohydrate metabolism because of the small sample size and relatively short duration of follow-up. Unlike fasting measurements, OGTT can detect all children with DCM.

Prevalence of metabolic syndrome and obesity in renal transplanted Mexican children

The purpose of the study was to evaluate the prevalence of MS and obesity in Mexican children with more than one yr post-renal transplantation. Thirty-two children transplanted between January 2004 and February 2006 were included in the study. The weight and height at the time of renal transplant were obtained. A fasting blood sample was drawn for serum creatinine, adiponectin, and complete lipid profile, and a three-h glucose tolerance test was also taken. A complete nutritional evaluation was performed including anthropometry. There was a statistically significant increase in BMI at one yr post-transplant that was maintained at two yr post-transplant. Three patients exhibited obesity and were overweight. Seventeen patients had hypertension, 14 patients had low HDL, 12 patients had hypertriglyceridemia, all had normal fasting glucose, six of them had glucose intolerance, and two had waist circumference higher than 90%. Eight patients (25%) had MS. Patients with MS had higher proportion of deceased donor grafts, acute rejection episodes, and received more methylprednisolone pulses; also they had a statistically significant higher pretransplant BMI than patients without MS. There was a significant relationship between BMI at one yr post-renal transplant and creatinine clearance estimated by Schwartz formula.

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.