Posttransplantation diabetes: a systematic review of the literature

Hyperglycemia after renal transplantation: frequency and risk factors

BACKGROUND

Chronic renal failure is an important and common complication of diabetes mellitus; hence, renal transplantation is a frequent and the acceptable treatment in patients with diabetic nephropathy requiring renal replacement therapy. On the other hand, renal transplantation and its conventional treatment can lead to increased diabetes outbreak in normoglycemic recipients. Also, uncontrolled hyperglycemia may be increased and allograft lost thus decreasing patient survival.

OBJECTIVES

We aimed to assess the frequency of hyperglycemia in transplant patients and its risk factors.

PATIENTS AND METHODS

A large retrospective study was performed on 3342 adult kidney transplant recipients between 2008 and 2010. Demographic and laboratory data were gathered for each patient. All tests were done in a single laboratory and hyperglycemia was defined as a fasting plasma glucose of > 125 mg/dL. Univariate and multivariate logistic regression analyses were used to determine the risk factors of hyperglycemia following kidney transplantation.

RESULTS

There were 2120 (63.4%) males and 1212 (36.3%) females. Prevalence of hyperglycemia was 22.5%. By univariate linear regression, hyperglycemia was significantly higher in patients with CMV infection (P = 0.001), elevated serum creatinine (P = 0.000), low HDL (P = 0.01), and increased blood levels of cyclosporine (P = 0.000). After adjusting for covariates by multivariate logistic regression, the hyperglycemia rate was significantly higher for patients with Cyclosporine trough level > 250 (P = 0.000), serum creatinine > 1.5 (P = 0.000) and HDL < 45 (P = 0.03).

CONCLUSIONS

This study indicated that hyperglycemia is a common metabolic disorder in Iranian kidney transplant patients. Risk factors for hyperglycemia were higher Cyclosporine level, impaired renal function, and reduced HDL value.

New-onset diabetes after kidney transplantation: prevalence, risk factors, and management

New-Onset Diabetes After Transplantation (NODAT) is an increasingly recognized severe metabolic complication of kidney transplantation causing lower graft function and survival and reduced long-term patient survival mainly due to cardiovascular events. The real incidence of NODAT after kidney transplantation is difficult to establish, because different classification systems and definitions have been employed over the years. Several risk factors, already present before or arising after transplantation, in particular the employed immunosuppressive regimens, have been related to the development of NODAT. However the responsible pathogenic mechanisms are still far to be perfectly known. Awareness of NODAT and of the NODAT-related factors is of paramount importance for the clinicians in order to individuate higher risk patients and arrange screening strategies. The risk of NODAT can be reduced by planning preventive measures and by tailoring immunosuppressive regimens according to the patient characteristics. Once NODAT has been diagnosed, the administration of specific anti-hyperglycemic therapy is mandatory to reach a tight glycemic control, which contributes to significantly reduce posttransplant mortality and morbidity.

Ablation of calcineurin Aβ reveals hyperlipidemia and signaling cross-talks with phosphodiesterases

Insulin resistance, hyperlipidemia, and cardiovascular complications are common dysregulations of metabolic syndrome. Transplant patients treated with immunosuppressant drugs such as cyclosporine A (CsA), an inhibitor of calcineurin phosphatase, frequently develop similar metabolic complications. Although calcineurin is known to mediate insulin sensitivity by regulating β-cell growth and adipokine gene transcription, its role in lipid homeostasis is poorly understood. Here, we examined lipid homeostasis in mice lacking calcineurin Aβ (CnAβ(-/-)). We show that mice lacking calcineurin Aβ are hyperlipidemic and develop age-dependent insulin resistance. Hyperlipidemia found in CnAβ(-/-) mice is, in part, due to increased lipolysis in adipose tissues, a process mediated by β-adrenergic G-protein-coupled receptor signaling pathways. CnAβ(-/-) mice also exhibit additional pathophysiological phenotypes caused by the potentiated GPCR signaling pathways. A cell autonomous mechanism with sustained cAMP/PKA activation is found in CnAβ(-/-) mice or upon CsA treatment to inhibit calcineurin. Increased PKA activation and cAMP accumulation in CnAβ(-/-) mice, however, are sensitive to phosphodiesterase inhibitor. Indeed, we show that calcineurin regulates degradation of phosphodiesterase 3B, in addition to phosphodiesterase 4D. These results establish a role for calcineurin in lipid homeostasis. These data also indicate that potentiated cAMP signaling pathway may provide an alternative molecular pathogenesis for the metabolic complications elicited by CsA in transplant patients.

Management of post-transplant diabetes

New onset diabetes mellitus after transplant (NODAT) refers to the development of diabetes post-transplant in previously non-diabetic patients and is associated with increased rates of acute transplant rejection, infection, late cardiovascular events, and decreased survival. NODAT is primarily due to the immunosuppressive drug regimen but the standard predisposing risk factors for diabetes also pertain. NODAT is diagnosed by the standard ADA criteria, once prednisone doses are less than 10 mg per day and in the absence of acute illness. Sulfonylureas, metformin, DPP-4 inhibitors, GLP-1 agonists, and insulin can be used in treatment, but when there is impaired kidney or hepatic function, special precautions are necessary. In addition, those drugs interacting with P450 enzymes require additional consideration because of possible interaction with immunosuppressive drug metabolism.

Characteristics of diabetes after pediatric liver transplant

Studies of DALT in pediatric recipients describe incidence and risk factors, but diagnostic criteria varied. This study reports characteristics and course of pediatric DALT by established diabetes criteria. Retrospective chart review of pediatric LT recipients evaluated for hyperglycemia (1/1/1997-12/30/2009) and matched, non-diabetic controls. DALT: random blood glucose >11.1 mm, ≥ 2 times, with insulin treatment. DALT diagnosed in 8.0% (24/300) included 7/24 (29.2%) with severe hyperglycemia (>27.7 mm), ketoacidosis in 2/24 (8.3%). At diagnosis, age was ≥ 11 yr old in 22/24 (91.7%); body mass was lean (BMIz -0.2 ± 1.5). Mean blood glucose was 24.6 mm with negative diabetes autoantibodies (19/19) and elevated C-peptide (2.3 nm). DALT onset median 5.0 months included 29.1% >12 months. Insulin duration median 4.6 months included 41.7% >6 months. DALT resolved in 83.3% over 4.9 (0.9-9.1) yr. DALT differed from controls by increased preceding rejections, prednisolone dose, tacrolimus level, and triple immunosuppression (all p < 0.01). In conclusion, pediatric DALT occurred in non-obese adolescents with insulin resistance, distinct from diabetes types 1 or 2. DALT was associated with preceding rejection and increased immunosuppression. Blood glucose monitoring, especially during increased immunosuppression following LT, could allow early diagnosis and reduce morbidity.

The immunosuppressive agents rapamycin, cyclosporin A and tacrolimus increase lipolysis, inhibit lipid storage and alter expression of genes involved in lipid metabolism in human adipose tissue

Cyclosporin A (CsA), tacrolimus and rapamycin are immunosuppressive agents (IAs) associated with insulin resistance and dyslipidemia, although their molecular effects on lipid metabolism in adipose tissue are unknown. We explored IAs effects on lipolysis, lipid storage and expression of genes involved on lipid metabolism in isolated human adipocytes and/or adipose tissue obtained via subcutaneous and omental fat biopsies. CsA, tacrolimus and rapamycin increased isoproterenol-stimulated lipolysis and inhibited lipid storage by 20-35% and enhanced isoproterenol-stimulated hormone-sensitive lipase Ser552 phosphorylation. Rapamycin also increased basal lipolysis (~20%) and impaired insulin's antilipolytic effect. Rapamycin, down-regulated the gene expression of perilipin, sterol regulatory element-binding protein 1 (SREBP1) and lipin 1, while tacrolimus down-regulated CD36 and aP2 gene expression. All three IAs increased IL-6 gene expression and secretion, but not expression and secretion of TNF-α or adiponectin. These findings suggest that CsA, tacrolimus and rapamycin enhance lipolysis, inhibit lipid storage and expression of lipogenic genes in adipose tissue, which may contribute to the development of dyslipidemia and insulin resistance associated with immunosuppressive therapy.

Hyperglycemia related to high-dose glucocorticoid use in noncritically ill patients

BACKGROUND

Glucocorticoids commonly cause drug-induced diabetes. This association is well recognized but available evidence does not answer clinically relevant issues in subjects without diabetes.

METHODS

Thirty-five individuals without diabetes with a recent diagnosis of acute lymphoblastic leukemia or non-Hodgkin's lymphoma on high-dose glucocorticoid therapy were studied. Close systematic monitoring of fasting and postprandial glycemia and fasting insulin determinations, HOMA-insulin resistance and HOMA β-cell function were performed. The primary objective was to define the incidence of secondary diabetes in patients treated with high-dose glucocorticoids. Secondary objectives were to specify the intensity, the moment it appears and the evolution of hyperglycemia, in addition to the risk factors, mechanisms and impact of continuous and cyclical glucocorticoids on the development of hyperglycemia.

RESULTS

Mean age of patients was 38.4 ± 18.7 years. The incidence of diabetes was 40.6% and was found after the first week; half the time it occurred between the second and fourth. Two-thirds spontaneously normalized by eight weeks. Continuous glucocorticoid administration had a higher incidence of fasting hyperglycemia (P = 0.003). Mean peak insulin levels were significantly higher in cases of diabetes.

CONCLUSIONS

High-dose prednisone for 2 to 3 months produced an elevated incidence of diabetes, usually with mild hyperglycemia occurring between the second and fourth week, normalizing spontaneously in all cases. Hyperglycemia was more frequent with continuous doses and occurred in cases with increased insulin resistance. The clinical and therapeutic characteristics of our participants, who were otherwise healthy, could represent the clinical setting of many patients with illness from other medical areas that might require high doses of GC for six to twelve weeks.

In vitro effects of mycophenolic acid on survival, function, and gene expression of pancreatic beta-cells

Post-transplant diabetes mellitus represents an important complication of prolonged immunosuppressive treatment after solid organ transplantation. The immunosuppressive toxicity, responsible for a persistent impairment of glucose metabolism in pancreatic islet-transplanted patients, is mainly attributed to calcineurin inhibitors and steroids, while other immunosuppressive molecules (azathioprine and mycophenolic acid, MPA) are considered not to have a toxic effect. In the present study, in vitro effects of MPA have been investigated in mouse beta-cell lines (βTC-1 and βTC-6) and in purified human pancreatic islets. βTC-1, βTC-6, and human pancreatic islets were exposed to various concentrations of MPA for different times. Consequently, we evaluated the viability, the induction of apoptosis, the glucose-stimulated insulin secretion, and the expression of β-cell function genes (Isl1, Pax6, Glut-2, glucokinase) and apoptosis-related genes (Bax and Bcl2). βTC-1, βTC-6, and human islets treated, respectively, for 48 and 72 h with 15-30 nM MPA showed altered islet architecture, as compared with control cells. We observed for βTC-1 and βTC-6 almost 70% reduction in cell viability; three to sixfold induction of TUNEL/apoptotic-positive cells quantified by FACS analysis. A twofold increase in apoptotic cells was observed in human islets after MPA exposure associated with strong inhibition of glucose-stimulated insulin secretion. Furthermore, we showed significant down-regulation of gene expression of molecules involved in β-cell function and increase rate between Bax/Bcl2. Our data demonstrate that MPA has an in vitro diabetogenic effect interfering at multiple levels with survival and function of murine and human pancreatic β-cells.

The impact of calcineurin inhibitors on insulin sensitivity and insulin secretion: a randomized crossover trial in uraemic patients

AIMS

The calcineurin inhibitors cyclosporine and tacrolimus are implicated in post-transplant complications such as new-onset diabetes after transplantation. The relative contribution of each calcineurin inhibitor to new-onset diabetes after transplantation remains unclear. We sought to compare the impact of cyclosporine and tacrolimus on glucose metabolism in humans.

METHODS

Eight haemodialysis patients received 8-10 days of oral treatment followed by 5-h infusions with cyclosporine, tacrolimus and saline in a randomized, investigator-blind, crossover study. Glucose metabolism and β-cell function was investigated through: a hyperinsulinaemic-euglycaemic clamp, an intravenous glucose tolerance test and insulin concentration time series.

RESULTS

Cyclosporine and tacrolimus decreased insulin sensitivity by 22% (P = 0.02) and 13% (P = 0.048), respectively. The acute insulin response and pulsatile insulin secretion were not significantly affected by the drugs.

CONCLUSION

In conclusion, 8-10 days of treatment with cyclosporine and tacrolimus impairs insulin sensitivity to a similar degree in haemodialysis patients, while acute insulin responses and pulsatile insulin secretion remain unaffected.

Diabetes and kidney transplantation: past, present, and future

Diabetes mellitus is the most common etiology for end stage renal disease (ESRD) worldwide and in the United States. The incidence of morbidity and mortality is higher in diabetic patients with ESRD due to increased cardiovascular events. Patients with type 2 diabetes who receive a renal allograft have a higher survival rate compared with patients who are maintained on chronic hemodialysis therapy, but there is scarcity of data on long-term graft outcomes. Most recently the development of new onset diabetes after transplantation (NODAT) poses a serious threat to patient and allograft survival. Pre-emptive transplantation and the use of living donors have improved overall survival. In addition, critical management of glucose, blood pressure, and cholesterol are some of the factors that can help minimize adverse outcomes in both patients with pre-existing diabetes and patients who develop NODAT. Future clinical trials are warranted to improve therapeutic medical management of these patients thus influencing graft attrition.

Post-transplant diabetes mellitus - risk factors and effects on the function and morphology of the allograft

The incidence of post-transplant diabetes mellitus and its effects on the kidney allograft function and morphology were assessed. Patients were divided into three groups according to their glucose metabolism. Risk factors for diabetes were first assessed, and then changes in renal function were checked. Morphological changes in the allografts were examined by protocol biopsies. The overall incidence of diabetes was 16%. The development of diabetes was influenced significantly by the body mass index, the body weight and the age of the recipient. The incidence of diabetes was 8.6% in patients on cyclosporine A therapy and 28.8% in those on tacrolimus (p < 0.05). As to the morphology of the kidney, a significantly higher proportion of the biopsies showed severe interstitial fibrosis/tubular atrophy (p = 0.0004) and subclinical acute rejection ( p = 0.001) in the diabetic group compared to the normal one. This clinical study has revealed that the adverse effect of diabetes on the allograft can be detected with protocol biopsy before the manifestation of a functional deterioration.

Long-term outcome after liver transplantation

Liver transplantation is a life-saving therapy for patients with end-stage liver disease, acute liver failure, and liver tumors. Over the past 4 decades, improvements in surgical techniques, peritransplant intensive care, and immunosuppressive regimens have resulted in significant improvements in short-term survival. Focus has now shifted to addressing long-term complications and improving quality of life in liver recipients. These include adverse effects of immunosuppression; recurrence of the primary liver disease; and management of diabetes, hypertension, dyslipidemia, obesity, metabolic syndrome, cardiovascular disease, renal dysfunction, osteoporosis, and de novo malignancy. Issues such as posttransplant depression, employment, sexual function, fertility, and pregnancy must not be overlooked, as they have a direct impact on the liver recipient's quality of life. This review summarizes the latest data in long-term outcome after liver transplantation.

Diabetes before and after lung transplantation in patients with cystic fibrosis and other lung diseases

AIMS

The aims of the study are to investigate the prevalence of diabetes in patients with cystic fibrosis compared with patients without cystic fibrosis, and its impact on the outcome after lung transplantation.

METHODS

Data were reviewed from 77 lung transplantation recipients in our centre between 2001 and 2010; 43 patients had cystic fibrosis and 34 patients had other lung diseases (no cystic fibrosis). To define diabetes, we used the American Diabetes Association definition.

RESULTS

Before lung transplantation, diabetes was diagnosed in 63% of patients with cystic fibrosis and 6% of patients without cystic fibrosis (P<0.001). In both groups, approximately 60% of the patients at risk developed new-onset diabetes after transplantation. The mortality in patients with cystic fibrosis was higher in patients with diabetes diagnosed before lung transplantation compared with those without (44 vs. 6%, P=0.04). Diabetes remained an independent factor in multivariate analyses.

CONCLUSIONS

Diabetes diagnosed before lung transplantation has a negative effect on survival after lung transplantation in patients with cystic fibrosis. Pre-existing diabetes is common in patients with cystic fibrosis, in contrast to patients without cystic fibrosis. Development of new-onset diabetes after transplantation is similar in both groups.

Metabolic syndrome after liver transplantation: Preventable illness or common consequence?

The metabolic syndrome is common after liver transplant being present in approximately half of recipients. It has been associated with adverse outcomes such as progression of hepatitis C and major vascular events. As the United States population ages and the rate of obesity increases, prevention of the metabolic syndrome in the post-transplant population deserves special consideration. Currently, the metabolic syndrome after transplant appears at least two times more common than observed rates in the general population. Specific guidelines for patients after transplant does not exist, therefore prevention rests upon knowledge of risk factors and the presence of modifiable elements. The current article will focus on risk factors for the development of the metabolic syndrome after transplant, will highlight potentially modifiable factors and propose potential areas for intervention. As in the non-transplant population, behavioral choices might have a major role. Opportunities exist in this regard for health prevention studies incorporating lifestyle changes. Other factors such as the need for immunosuppression, and the changing characteristics of wait listed patients are not modifiable, but are important to know in order to identify persons at higher risk. Although immunosuppression after transplant is unavoidable, the contribution of different agents to the development of components of the metabolic syndrome is also discussed. Ultimately, an increased risk of the metabolic syndrome after transplant is likely unavoidable, however, there are many opportunities to reduce the prevalence.

Cellular and physiological mechanisms of new-onset diabetes mellitus after solid organ transplantation

New-onset diabetes after transplantation is recognized as one of the metabolic consequences which may increase the risk of morbidity and mortality after solid organ transplantation. The pathophysiology of new-onset diabetes after transplantation has not been clearly defined and may resemble that of Type 2 diabetes, characterized by predominantly insulin resistance or defective insulin secretion, or both. This review aims to summarize the current state of knowledge regarding the prevalence, consequences, pathogenesis, and management of new-onset diabetes after transplantation, with a major focus on the possible mechanisms involved in the pathogenesis of the disorder. The aetiology of new-onset diabetes after transplantation is multifactorial, with diabetogenic immunosuppressive drugs playing a major role. Multiple cellular and physiologic mechanisms are involved in the process. Selection of an appropriate maintenance immunosuppressive regimen should involve balancing the risk of patient and graft survival vs. the potential for new-onset diabetes after transplantation.

Calcineurin inhibitors acutely improve insulin sensitivity without affecting insulin secretion in healthy human volunteers

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

New onset diabetes after transplantation is related to treatment with immunosuppressive medications. Clinical studies have shown that risk of new onset diabetes is greater with tacrolimus compared with ciclosporin. The diabetogenicity of ciclosporin and tacrolimus has been attributed to both beta cell dysfunction and impaired insulin sensitivity.

WHAT THIS STUDY ADDS

This is the first trial to investigate beta cell function and insulin sensitivity using gold standard methodology in healthy human volunteers treated with clinically relevant doses of ciclosporin and tacrolimus. We document that both drugs acutely increase insulin sensitivity, while first phase and pulsatile insulin secretion remain unaffected. This study demonstrates that ciclosporin and tacrolimus have similar acute effects on glucose metabolism in healthy humans. AIM The introduction of calcineurin inhibitors (CNIs) ciclosporin (CsA) and tacrolimus (Tac) has improved the outcome of organ transplants, but complications such as new onset diabetes mellitus after transplantation (NODAT) cause impairment of survival rates. The relative contribution of each CNI to the pathogenesis and development of NODAT remains unclear. We sought to compare the impact of CsA and Tac on glucose metabolism in human subjects.

METHODS

Ten healthy men underwent 5 h infusions of CsA, Tac and saline in a randomized, double-blind, crossover study. During infusion glucose metabolism was investigated using following methods: a hyperinsulinaemic-euglycemic clamp, an intravenous glucose tolerance test (i.v.GTT), glucose-stimulated insulin concentration-time series and indirect calorimetry.

RESULTS

Clamp derived insulin sensitivity was increased by 25% during CsA (P < 0.0001) and 13% during Tac administration (P = 0.047), whereas first phase and pulsatile insulin secretion were unaffected. Coinciding with the CNI induced improved insulin sensitivity, glucose oxidation rates increased, while insulin clearance rates decreased, only non-significantly. Tac singularly lowered hsCRP concentrations, otherwise no changes were observed in circulating glucagon, FFA or adiponectin concentrations. Mean blood concentrations of CNIs were 486.9 ± 23.5 µg l(-1) for CsA and 12.8 ± 0.5 µg l(-1) for Tac.

CONCLUSIONS

Acute effects of i.v. CsA, and to a lesser degree Tac infusions, in healthy volunteers include increased insulin sensitivity, without any effect on first phase or pulsatile insulin secretion.

Analysis of common type 2 diabetes mellitus genetic risk factors in new-onset diabetes after transplantation in kidney transplant patients medicated with tacrolimus

Purpose

New-onset diabetes after transplantation (NODAT) is a major complication after kidney transplantation. The risk factors for NODAT include the use of calcineurin inhibitors as part of the immunosuppressive regimen, among which tacrolimus has the most pronounced diabetogenic effect. Both NODAT and type 2 diabetes mellitus (T2DM) share several risk factors. Recent studies have identified a number of common genetic variants associated with increased risk of T2DM. Here we report the results of our study on the potential effect of single nucleotide polymorphisms (SNPs) previously associated with T2DM on the risk of NODAT in kidney transplant patients medicated with tacrolimus.

Methods

Seven SNPs in six genes known to increase the risk of T2DM in Caucasians were genotyped by means of TaqMan assays in 235 kidney transplant patients medicated with tacrolimus: rs4402960 and rs1470579 in IGF2BP2; rs1111875 in HHEX; rs10811661 upstream of CDKN2A/B; rs13266634 in SLC30A8; rs1801282 in PPARG; rs5215 in KCNJ11. The TCF7L2 rs7903146 SNP was also included in the multivariate analysis.

Results

None of the analyzed SNPs was significantly associated with the risk of NODAT. However, the IGF2BP2 rs4402960 T allele was present significantly more frequently among patients diagnosed with NODAT more than 2 weeks after transplantation (p = 0.048). Mean (± standard deviation) number of the analyzed alleles tended to be lower in patients without NODAT (6.19 ± 1.71) than in NODAT patients (6.58 ± 1.1.95; p = 0.09) and significantly lower compared to late-onset NODAT patients (7.03 ± 1.88; p = 0.018). Multivariate analysis confirmed the significance of ‘diabetogenic’ allele number in late-onset NODAT development [odds ratio (OR) 1.37, 95 % confidence interval (CI) 1.05–1.78; p = 0.017]. Additionally, individuals carrying >7 of the analyzed ‘diabetogenic’ alleles were at a significantly higher risk of NODAT (OR 2.17, 95 % CI 1.18–3.99; p = 0.015).

Conclusions

Complex analysis of genotypes increasing the risk of diabetes may lead to the identification of NODAT susceptibility predictors.

New onset diabetes after kidney transplantation in autosomal dominant polycystic kidney disease: a retrospective cohort study

BACKGROUND

New onset diabetes after transplantation (NODAT) is a common adverse outcome of organ transplantation that increases the risk of cardiovascular disease, infection and graft rejection. In kidney transplantation, apart from traditional risk factors, autosomal dominant polycystic kidney disease (ADPKD) has also been reported by several authors as a predisposing factor to the development of NODAT, but any rationale for an association between ADPKD and NODAT is unclear. We examined the cumulative incidence of NODAT in or own transplant population comparing ADPKD patients with non-ADPKD controls.

METHODS

A retrospective cohort study to determine the cumulative incidence of patients developing NODAT (defined by World Health Organization-based criteria and/or use of hypoglycaemic medication) was conducted in 79 patients with ADPKD (79 transplants) and 423 non-ADPKD controls (426 transplants) selected from 613 sequential transplant recipients over 8 years. Patients with pre-existing diabetes as a primary disease or comorbidity and/or with minimal follow up or early graft loss/death were excluded.

RESULTS

Of the 502 patients (505 transplants) studied, 86 (17.0%) developed NODAT. There was no significant difference in the cumulative incidence of NODAT in the ADPKD (16.5%; CI 13.6-20.7%) compared with the non-ADPKD (17.1%; CI 8.3-24.6%) control group. Of the 13 patients in the ADPKD group with NODAT, three required treatment with insulin with or without oral hypoglycaemic agents. Among the 73 NODAT patients in the non-ADPKD group, eight received insulin with or without oral hypoglycaemics. Furthermore, of the patients that did develop NODAT, there was no difference in the time to its development in patients with and without ADPKD.

CONCLUSION

There was no evidence of an increased incidence of NODAT in ADPKD kidney transplant recipients.

Implication of mitochondrial cytoprotection in human islet isolation and transplantation

Islet transplantation is a promising therapy for type 1 diabetes mellitus; however, success rates in achieving both short- and long-term insulin independence are not consistent, due in part to inconsistent islet quality and quantity caused by the complex nature and multistep process of islet isolation and transplantation. Since the introduction of the Edmonton Protocol in 2000, more attention has been placed on preserving mitochondrial function as increasing evidences suggest that impaired mitochondrial integrity can adversely affect clinical outcomes. Some recent studies have demonstrated that it is possible to achieve islet cytoprotection by maintaining mitochondrial function and subsequently to improve islet transplantation outcomes. However, the benefits of mitoprotection in many cases are controversial and the underlying mechanisms are unclear. This article summarizes the recent progress associated with mitochondrial cytoprotection in each step of the islet isolation and transplantation process, as well as islet potency and viability assays based on the measurement of mitochondrial integrity. In addition, we briefly discuss immunosuppression side effects on islet graft function and how transplant site selection affects islet engraftment and clinical outcomes.

Glutathione S-transferase gene polymorphisms are not major risks for susceptibility to posttransplantation diabetes mellitus in Taiwan renal transplant recipients

Glutathione S-transferase (GST) M1 null genotype has been reported playing a significant role in the diabetes mellitus (DM) susceptibility in Turkish population. We investigated whether the GSTM1, GSTA1, and GSTP1 gene polymorphisms are associated with posttransplantation diabetes mellitus (PTDM) in Taiwan. There were 283 renal transplant recipients (RTRs) enrolled. Polymerase chain reaction-restriction fragment length polymorphism was used for the measurement of GSTA1, M1, and P1 genetic polymorphisms. PTDM was diagnosed according to the American Diabetes Association guidelines. Eight-five patients (30%) were diagnosed with PTDM. The averaged posttransplant follow-up period was 77.9 ± 27.2 months. Duration from transplantat to diagnosis of PTDM ranged from 0.2 to 103.1 months (19.2 ± 26.3 months). There were significantly differences between non-DM and PTDM groups in age (50.6 ± 11.0 vs. 54.6 ± 9.36 years, P = 0.005), BMI (22.4 ± 3.6 vs. 24.3 ± 3.8, P<0.001). The distributions of GSTA1, GSTP1, and GSTM1 genotypes alleles were not significantly different between PTDM and non-DM group. Patients carrying the different GSTA1, GSTP1, and GSTM1 genetic and allelic polymorphisms had no differences for the development of PTDM. These overall results suggested a lack of strong association with GSTA1, GSTP1, and GSTM1 genetic polymorphisms to the susceptibility of PTDM in Taiwanese RTRs.

Prevalence and risk factors of pre-diabetes after renal transplantation: a single-centre cohort study in 200 consecutive patients

BACKGROUND

After renal transplantation, patients are prone to develop impairments in glucose metabolism. In 2005, the American Diabetes Association published new guidelines on the diagnosis of pre-diabetes [plasma glucose levels from 100 to 125 mg/dL fasting or from 140 to 199 mg/dL 2 h after an oral glucose tolerance test (OGTT)]. This study sought to evaluate the prevalence and the potentially associated factors of pre-diabetes in a cohort of renal transplant patients on maintenance immunosuppressive medication. Furthermore, the diagnostic value of HbA1-c measurements in predicting pre-diabetes in transplant patients is undetermined.

METHODS

Two hundred consecutive renal transplant patients of our outpatient transplant clinic were evaluated using a standard OGTT. On the day of testing, multiple factors presumably associated with pre-diabetes were assessed via a standardized questionnaire: daily steroid dosage, triglyceride levels, cholesterol levels, estimated glomerular filtration rate (eGFR) [abbreviated Modification of Diet in Renal Disease (MDRD) formula], systolic and diastolic blood pressure, pulse pressure, age, gender, body mass index (BMI), BMI <>30 and <>25, number of renal transplants, number of rejection episodes prior to testing, source of renal transplant, cause of renal failure and medications as related to the prescription of cyclosporine, tacrolimus, mycophenolate mophetil, angiotensin-converting enzyme inhibitors, AT1-blockers, statins, β-blockers and thiazide diuretics. Patients diagnosed with pre-diabetes were compared to subjects with normal test results. Fishers exact test and the Wilcoxon rank-sum test were applied to compare the two study populations, whereas multivariate logistic regression was used to seek potential risk factors as related to other covariates. Risk ratios (RRs) to develop pre-diabetes were calculated for significant variables.

RESULTS

Ten patients had results indicative of post-transplant diabetes whereas data sets of three other patients were incomplete and were thus not included in the analysis. From the remaining 187 patients, 130 (69.5%) displayed normal test results whereas 57 (30.5%) had results indicative of pre-diabetes. On multivariate regression analysis, patients with pre-diabetes were significantly older {55.3 ± 12.1 versus 47.7 ± 12.6 years, P = 0.0007, RRs per 5 years increase 1.28 [95% confidence interval (95% CI) 1.11-1.47]}, had more rejection episodes [0.26 ± 0.48 versus 0.12 ± 0.37, P = 0.0024, RRs per rejection episode 3.99 (95% CI 1.63-9.77)] and showed lower diastolic blood pressure readings [77 ± 10 mmHg versus 81 ± 10 mmHg, P = 0.0362, RR per 5 mmHg decrease 1.14 (95% CI 1.04-1.49)].

CONCLUSIONS

There is a high incidence of latent pre-diabetes among renal transplant recipients. Increasing age, rejection episodes and lower diastolic blood pressure proved to be associated with pre-diabetes. In contrast to post-transplant diabetes, tacrolimus use and HbA1-c levels were not prognostic of pre-diabetes.

Prednisone affects inflammation, glucose tolerance, and bone turnover within hours of treatment in healthy individuals

OBJECTIVE

Use of glucocorticoids for anti-inflammatory efficacy is limited by their side effects. This study examined, in the same individuals, prednisone's acute, dose-dependent effects on inflammation as well as biomarkers of glucose regulation and bone homeostasis.

DESIGN

In this randomized, double-blind, parallel-design trial of healthy adults demonstrating cutaneous allergen-induced hypersensitivity, patients received placebo or prednisone 10, 25 or 60 mg daily for 7 days.

METHODS

Effects on peripheral white blood cell (WBC) count, ex vivo whole blood lipopolysaccharide (LPS)-stimulated TNF-α release and response to cutaneous allergen challenge were assessed concurrently with biomarkers for glucose tolerance and bone turnover.

RESULTS

Differential peripheral WBC counts changed significantly within hours of prednisone administration. Ex vivo, LPS-stimulated TNF-α was significantly reduced by all prednisone doses on days 1 and 7. The late phase cutaneous allergen reaction was significantly reduced with prednisone 60 mg vs placebo on days 1 and 7. Oral glucose tolerance tests revealed significant increases in glycaemic excursion on days 1 and 7, whereas increases in insulin and C-peptide excursions were more notable on day 7 with all doses of prednisone. The bone formation markers osteocalcin, and procollagen I N- and C-terminal peptides decreased significantly on days 1 and 7 vs placebo.

CONCLUSIONS

In healthy young adults after single doses as low as 10 mg, prednisone treatment has significant effects on glucose tolerance and bone formation markers within hours of treatment, in parallel with anti-inflammatory effects.

Prediction at first year of incident new-onset diabetes after kidney transplantation by risk prediction models

OBJECTIVE

Our aim was to analyze the performance of two scores developed for predicting diabetes in nontransplant populations for identifying kidney transplant recipients with a higher new-onset diabetes mellitus after transplantation (NODAT) risk beyond the first year after transplantation.

RESEARCH DESIGN AND METHODS

We analyzed 191 kidney transplants, which had at least 1-year follow-up posttransplant. First-year posttransplant variables were collected to estimate the San Antonio Diabetes Prediction Model (SADPM) and Framingham Offspring Study-Diabetes Mellitus (FOS-DM) algorithm.

RESULTS

Areas under the receiver operating characteristic curve of FOS-DM and SADPM scores to predict NODAT were 0.756 and 0.807 (P < 0.001), respectively. FOS-DM and SADPM scores over 75 percentile (hazard ratio 5.074 and 8.179, respectively, P < 0.001) were associated with NODAT.

CONCLUSIONS

Both scores can be used to identify kidney recipients at higher risk for NODAT beyond the first year. SADPM score detects some 25% of kidney transplant patients with an eightfold risk for NODAT.

Renal resistive index as a new independent risk factor for new-onset diabetes mellitus after kidney transplantation

Pulse pressure and urinary albumin excretion were recently identified as risk factors of new-onset diabetes after renal transplantation (NODAT), suggesting that microvascular injury may be implicated in NODAT. However, the relationship between of microvascular injury and NODAT is unknown. In the present long-term (median follow-up: 5.7years; observation period: 4908 patient-years) retrospective study in 656 renal transplant recipients, the association between baseline renal resistance index (RI, used as a marker of widespread microvascular damage) and the incidence of NODAT was assessed. The incidence of NODAT was 11.2% and 14.6% at 5 and 10years, respectively, after transplantation. RI at 3months was a risk factor for NODAT [hazard ratio (HR) per 0.1: 2.19 (1.55-3.09), P<0.0001]. RI >0.75 (vs. 0≤0.75) was a potent a predictor of NODAT [HR: 3.29 (1.91-5.67), P<0.0001], even after adjustments [HR: 3.29 (1.50-7.24), P=0.0030] on age, weight, glucose, nephropathy, and arterial pressure. Similar results were observed when RI was measured at 1month [HR per 0.1:1.74 (1.33-2.27), P<0.0001] and 12months [HR per 0.1:1.74 (1.33-2.27), P<0.0001] after transplantation. High RI early after renal transplantation is a long-term risk factor for NODAT, and could be used to refine the individual risk of NODAT.

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.

Optimization of the use of Calcineurin inhibitors in liver transplantation

Calcineurin inhibitors (CNIs), such as cyclosporin A and tacrolimus, are the cornerstone of maintenance immunosuppressive regimens in liver transplantation. CNIs prevent rejection by inhibition of calcineurin, via which lymphocyte proliferation and interleukin (IL)-2 production is prevented. Tacrolimus is now the first-choice immunosuppressant after liver transplantation, since it is associated with fewer episodes of rejection than cyclosporin A. In this review we will discuss interindividual differences, which influence tacrolimus metabolism. Because of these factors and the narrow therapeutic index of tacrolimus, monitoring of drug trough levels is necessary. Furthermore, we will discuss studies concerning conversion from the tacrolimus twice daily to tacrolimus once daily formulation in stable LT patients. Due to adverse effects of CNIs, such as chronic renal failure, hypertension, de novo malignancy and new-onset diabetes mellitus, CNI minimization strategies have been developed, which will be discussed too.

Association of transcription factor 7-like 2 (TCF7L2) gene polymorphism with posttransplant diabetes mellitus in kidney transplant patients medicated with tacrolimus

New onset posttransplant diabetes mellitus (PTDM) has a high incidence after kidney transplantation in patients medicated with tacrolimus. PTDM can adversely affect patient and graft survival. The pathophysiology of PTDM closely mimics type 2 diabetes mellitus (T2DM). One of the possible genetic factors predisposing individuals to PTDM might be a polymorphism in the transcription factor 7-like 2 gene (TCF7L2). This polymorphism has previously been associated with increased risk of T2DM in the general population. Therefore, the present study aimed to evaluate TCF7L2 polymorphisms in PTDM in kidney transplant patients medicated with tacrolimus. Non-diabetic kidney transplant patients medicated with tacrolimus (n = 234) were genotyped for the presence of TCF7L2 gene variants (rs12255372 and rs7903146) using TaqMan probes. Of the 234 patients, 66 patients had developed PTDM and 168 had not. Frequencies of the studied single nucleotide polymorphisms (SNPs) did not differ significantly between the study groups. Moreover, haplotype analyses failed to detect any associations between TCF7L2 haplotypes and PTDM. However, in late-onset PTDM (developed later that 2 weeks from transplantation), frequencies of the rs7903146 TT genotype and T minor allele were significantly increased compared to non-PTDM controls (17.9% vs. 5.9%, p = 0.017, OR: 4.13, 95% CI: 1.19-14.33 for TT genotype, 39.3% vs. 25.9%, p = 0.038 for T allele). If the application of TCF7L2 rs7903146 SNPs as a marker for PTDM is confirmed by further independent studies, replacing tacrolimus with other immunosuppressants could be warranted in patients at high risk of PTDM, as diagnosed by TCF7L2 genotyping.

Perioperative management of the pediatric cardiac transplantation patient

OPINION STATEMENT

The major diagnoses carried by children undergoing cardiac transplantation worldwide are congenital heart defects, cardiomyopathies, and retransplantation. The leading diagnosis in infancy is congenital heart disease, whereas cardiomyopathy predominates in older children. In view of this wide spectrum of diagnoses, the perioperative management of these children requires medical, interventional, and surgical expertise in treatment of complex congenital heart defects, end-stage heart failure, and cardiac transplantation. According to the Pediatric Heart Transplantation Survey database, the majority of children listed for cardiac transplantation eventually require higher levels of cardiac support before transplantation. The team caring for these children should be prepared to escalate support in a timely fashion in order to avoid end-organ dysfunction or a catastrophic event that will remove the patient from the cardiac transplantation list. The first step is advanced hemodynamic monitoring in a specialized pediatric cardiac intensive care unit and initiation of inotropic support. Further escalation of care should be based on careful analysis of the hemodynamic profile, end-organ function, and biochemical markers of perfusion and myocardial stress. A patient who continues to deteriorate in spite of inotropic support requires positive pressure ventilation, and if deterioration continues, mechanical circulatory support is initiated. Cardiac transplantation is a challenging operation, and even more so in children with complex congenital heart defects. The abnormal cardiovascular anatomy requires planning and anticipation of possible pitfalls as hypoplasia of the aortic arch, abnormal pulmonary arteries, and abnormal systemic and pulmonary venous connections. The time required to remove adhesions in children with prior cardiac operations increases the ischemic time of the graft and the risk of primary graft dysfunction. Assessment of pulmonary vascular resistance in children with congenital heart defects is problematic, and even children with a normal transpulmonary gradient and pulmonary vascular resistance are at increased risk of postoperative pulmonary hypertension and right ventricular graft failure. The postoperative course is directly linked to the patient's preoperative physical condition and perioperative course. The induction of immunosuppression and the use of plasmapheresis in children with a positive cross-match may lead to further hemodynamic compromise. If severe primary graft dysfunction evolves, early initiation of extracorporeal membranous oxygenator is indicated to avoid irreversible end-organ dysfunction.

Prevention and management of transplant-associated diabetes

INTRODUCTION

New-onset diabetes after transplantation (NODAT) is considered to be a major cause of cardiovascular disease and death among patients with a functioning allograft. A major challenge is to reduce the incidence of NODAT and to treat it optimally once it has occurred.

AREAS COVERED

This review presents current data on how to prevent NODAT in patients at risk, with a focus on modifications in the immunosuppressive regimen. Current suggestions for detection and treatment of NODAT are also presented.

EXPERT OPINION

Prevention of NODAT is possible by assessing the patient's glycemic risk prior to transplantation and tailoring the treatment (e.g., choice and dosage of immunosuppressive agents) after transplantation. An oral glucose tolerance test is still the gold standard to detect NODAT in patients at risk (prediabetes) but algorithms can be used to select those who should be tested. The treatment of NODAT involves a broad approach on risk factors for cardiovascular events and graft loss. Future studies on the use of oral hypoglycemic agents in NODAT are still needed.

Adiponectin gene polymorphisms are associated with posttransplantation diabetes mellitus in Chinese renal allograft recipients

BACKGROUND

Posttransplantation diabetes mellitus (PTDM) is a well-recognized renal transplantation complication that is associated with increased graft loss, morbidity, and mortality. Adiponectin gene polymorphisms are associated with type 2 diabetes. However, it remains unknown whether these polymorphisms increase the risk for development of PTDM. Therefore, the aim of this study was to investigate the association between the adiponectin gene polymorphism and the risk of PTDM among Chinese renal allograft recipients.

METHODS

We genotyped 398 unrelated renal allograft recipients without a prior diagnosis of diabetes, including 97 PTDM and 301 without PTDM, for adiponectin gene variants: single nucleotide polymorphisms at position 45 and 276, that is, SNP-45: T/G, SNP-276: G/T, using the polymerase chain reaction-restriction fragment length polymorphism assay. No prisoners or organs from prisoners were used in the study.

RESULTS

The G allele of SNP-276 was significantly more frequent in PTDM than non-PTDM subjects (P = .041). For SNP-45 and SNP-276, the incidence of PTDM was significantly higher in patients with the GG genotype than those with the TG and TT genotypes (48.1% vs 21.5% and 23.6% and 30.7% vs 18.5% and 22.8%; (P = .011 and .024, respectively). Even after adjusting for age and sex, the effects of the SNP-45 genotypes for GG compared to TT (odds ratio [OR] = 3.108, P = .009) and GG compared to TG (OR = 3.620, P = .004) as well as for SNP-276 genotypes GG compared to TG (OR = 2.203, P = .002) and body mass index at transplantation (OR = 1.099, P = .024) remained significant.

CONCLUSIONS

These data suggested that SNP-45 and SNP-276 of the adiponectin gene were significantly associated with an increased risk for PTDM among Chinese renal allograft recipients.

Sirolimus therapy predisposes to new-onset diabetes mellitus after renal transplantation: a long-term analysis of various treatment regimens

PURPOSE

This retrospective analysis evaluated the impacts of sirolimus (SRL), cyclosporine (CsA), and steroids (S) on the occurrence, treatment, and complications of new-onset diabetes after transplantation (NODAT).

METHODS

We compared 4 groups: group 1, SRL plus full-exposure CsA/S (n = 118); group 2, full-exposure CsA/S/no SRL ± antiproliferative drug (n = 141); group 3, SRL plus reduced CsA exposure/S (n = 212); and group 4, no SRL/full-exposure CsA/S ± antiproliferative drug (n = 43).

RESULTS

NODAT rates reflected the level of CsA exposure; at 10 years 54% versus 30% for groups 1 versus 2 (P = .0001); at 5 years 30% versus 21% for Groups 3 versus 4 (P = .3); 81% of cases were detected within 1 year. The lower NODAT rate in group 3 reflected a benefit of reduced CsA exposure (P = .02; hazard ratio (HR), 1.006). Group 1 showed higher CsA (P = .0001) and lower SRL concentrations (P = .016) versus group 3. CsA exposure closely correlating with NODAT among group 1 (P = .0001) was the major difference between groups 1 and 3 (P = .04; HR, 0.97). Differences in steroid treatment did not play a significant role in NODAT. Comparing groups 1 and 2, SRL was an independent risk factor for NODAT (P = .004; HR, 3.5).

CONCLUSIONS

Our 10-year experience revealed SRL to be an etiologic agent for NODAT, displaying interactive, possibly pharmacokinetic, and pharmacodynamic effects with concomitant CsA in combination treatment.

New-onset diabetes after renal transplantation: diagnosis, incidence, risk factors, impact on outcomes, and novel implications

OBJECTIVE

New-onset diabetes after transplantation (NODAT) is a multifactorial, complex metabolic disorder associated with impaired long-term graft function, reduced recipient survival, and increased risks of cardiovascular disease and infectious complications. The impact of NODAT is generally underestimated partly due to the inconsistent criteria that have been previously used for its diagnosis and to the generally short observation periods. The aim of this article was to review the recent literature on NODAT and to highlight the novel implications.

FINDINGS

The 2010 American Diabetes Association guidelines provide useful, simplified criteria to unify the diagnosis including application of hemoglobin A1C levels. We sought to establish the impact of various modifiable and nonmodifiable risk factors. A vast number of papers have examined the effects of immunosuppressive medications on the development of NODAT: Neither calcineurin inhibitor nor sirolimus (SRL) or steroids seems to be innocent of contributing to it. Immunosuppressants account for 74% of the occurrence of NODAT. Among modifiable risk factors, obesity is independent and significant, with great prevalence in the population. In additional to lifestyle modifications, the role of bariatric surgery (BS) either before or after transplantation is highlighted herein as a strategy to reduce disease in the view of the results among overweight, nontransplanted patients.

SUMMARY

Because of the strong association between high glucose values in the early posttransplant period and the development of NODAT, the condition must be recognized early after (or even before) transplantation by intensive screening. Patients at risk for NODAT must modify appropriate risk factors and particularly undergo pretransplant planning and/or posttransplant adjustment individualizing immunosuppressive therapy to mitigate the risk of this serious complication.

Evaluation of weekly-reduction regimen of glucocorticoids in combination with cyclophosphamide for anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis in Japanese patients

The current therapeutic regimen recommended by the European League against Rheumatism (EULAR) for anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is continuation of initially administered doses of glucocorticoids (GCs) in combination with cyclophosphamide (CYC) for 1 month followed by gradual tapering. Considering the adverse effects of GCs, another tapering regimen of GCs with CYC, which was characterized by tapering GCs weekly, was reported by the British Society of Rheumatology (weekly-reduction regimen). The aim of the present study is to evaluate the safety and efficacy of this weekly-reduction regimen for Japanese AAV patients in comparison with the monthly-reduction regimen recommended by the EULAR. We retrospectively reviewed medical records of adult patients newly diagnosed with AAV during the period from April 2000 to December 2010. The outcome measures were rates of remission, relapse, infection, and GC-induced diabetes mellitus during the first 12 months. Clinical data in the two groups and categorial variables with a possible relation to the outcomes were compared by using the t test and chi-square test, respectively. Twenty-four patients were enrolled in our study. All of the patients achieved remission, and the rates of relapse during the first 12 months were not statistically different between the two groups (P = 0.16). Patients treated with the weekly-reduction regimen were less liable to have infection (P = 0.03) and impaired glucose tolerance (P = 0.017), compared with those treated with the monthly-reduction regimen. A therapeutic strategy using the weekly-reduction regimen of GCs would be effective and would have fewer side effects than the monthly-reduction regimen.

Long-term management of the liver transplant recipient: pearls for the practicing gastroenterologist

Liver transplantation is becoming more common and patients are surviving longer after transplantation. Special care must be paid to the long-term management of these patients because they are at increased risk for medical problems, malignancies, and adverse effects from immunosuppression. A stable and continuing relationship must be developed between the physician and the patient to optimize the long-term outcomes for these individuals.

Risk factors for medication-induced diabetes and type 2 diabetes

OBJECTIVE

To compare the prevalence of risk factors in children aged <18 years diagnosed with medication-induced diabetes mellitus versus those diagnosed with type 2 diabetes.

STUDY DESIGN

This retrospective observational study used data from a Canadian prospective surveillance study in which clinical features of new cases of type 2 diabetes (n = 225) and medication-induced diabetes (n = 58) were reported over a 2-year period. The presence of risk factors for type 2 diabetes (eg, obesity, family history of type 2 diabetes, ethnicity, acanthosis nigricans, hypertension, polycystic ovarian syndrome) was compared in the 2 groups using descriptive statistics and logistic regression.

RESULTS

Compared with the children with type 2 diabetes, the children with medication-induced diabetes were more likely to be Caucasian (P < .0001) and less likely to be obese (P < .0001), to have a positive family history of type 2 diabetes (P = .0001), to have acanthosis nigricans (P < .0001) on clinical examination, and to have an obesity-related comorbidity, such as polycystic ovarian syndrome (P = .04), dyslipidemia (P = .02), hypertension (P = .04), or an elevated alanine aminotransferase level (P = .05).

CONCLUSIONS

Evaluating for the typical risk factors for type 2 diabetes is not sufficient to identify all children at risk for developing medication-induced diabetes. Further studies are needed to help inform guidelines on screening for and prevention of medication-induced diabetes in children.

The long-term outcomes and costs of diabetes mellitus among renal transplant recipients: tacrolimus versus cyclosporine

Anti-rejection regimens for renal transplants have changed dramatically during the past 20 years, but there are few long-term studies relating cost, mortality, or graft failure simultaneously to disease-pharmacotherapy couplets. We analyzed US Renal Data System data on a matched-pair cohort of first, single organ kidney transplants from 1998 through 2002 over up to 5 years following transplantation for patients on tacrolimus or low-dose cyclosporine, stratifying by whether the recipient had pre-existing or new onset diabetes. Kaplan-Meier survival curves show mortality and survival differences associated with diabetes, but no additional incremental effects of immune suppression regimen. Significant cost increases are reported for patients receiving tacrolimus above and beyond the extra costs associated with diabetes.

Effect of different immunosuppressive regimens on the evolution of distinct metabolic parameters: evidence from the Symphony study

BACKGROUND

The metabolic syndrome (MS) is an important risk factor for graft dysfunction and patient death after renal transplantation. The aim of this sub-analysis of the Symphony study was to assess the progression of the laboratory parameters associated with MS in the first year after transplantation.

METHODS

Data collected from the Symphony study were used; 1645 patients were randomized to receive standard-dose cyclosporine (Stand-CsA), low-dose cyclosporine (Low-CsA), tacrolimus (Low-Tac) or sirolimus (Low-SRL), in addition to mycophenolate mofetil (MMF) and corticosteroids. Data were collected for levels and progression over the first year post-transplantation of systolic and diastolic blood pressure, uric acid, triglycerides, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol and fasting glucose levels by treatment arm.

RESULTS

The low-SRL group had significantly higher levels of triglycerides and LDL. The two CsA arms were associated with the highest uric acid levels at each time point. There were no significant differences in overall levels or changes in glucose or HDL. Patients in the standard-CsA arm had significantly higher diastolic blood pressure than those in the Low-SRL and Low-Tac arms. Systolic blood pressure was higher in the Low-CsA arm than in the Low-Tac arm. The use of antihypertensive and antidiabetic agents was similar between the treatment arms. In the Low-SRL arm, more patients were treated with lipid-lowering therapy. Mean daily steroid doses were the highest in the Low-SRL arm.

CONCLUSIONS

This sub-analysis demonstrates that there is a difference in metabolic parameters between immunosuppressive groups. CsA therapy was associated with the highest values of uric acid and systolic and diastolic blood pressure. Patients on SRL therapy had the worst lipaemic control. A possible effect of Tac on new-onset diabetes could not be excluded.

Unique cellular and mitochondrial defects mediate FK506-induced islet β-cell dysfunction

OBJECTIVE

To determine biological mechanisms involved in posttransplantation diabetes mellitus caused by the immunosuppressant tacrolimus (FK506).

METHODS

INS-1 cells and isolated rat islets were incubated with vehicle or FK506 and harvested at 24-hr intervals. Cells were assessed for viability, apoptosis, proliferation, cell insulin secretion, and content. Gene expression studies by microarray analysis, quantitative polymerase chain reaction, and motifADE analysis of the microarray data identified potential FK506-mediated pathways and regulatory motifs. Mitochondrial functions, including cell respiration, mitochondrial content, and bioenergetics were assessed.

RESULTS

Cell replication, viability, insulin secretion, oxygen consumption, and mitochondrial content were decreased (P<0.05) 1.2-, 1.27-, 1.77-, 1.32-, and 1.43-fold, respectively, after 48-hr FK506 treatment. Differences increased with time. FK506 (50 ng/mL) and cyclosporine A (800 ng/mL) had comparable effects. FK506 significantly decreased mitochondrial content and mitochondrial bioenergetics and showed a trend toward decreased oxygen consumption in isolated islets. Cell apoptosis and proliferation, mitochondrial DNA copy number, and ATP:ADP ratios were not significantly affected. Pathway analysis of microarray data showed FK506 modification of pathways involving ATP metabolism, membrane trafficking, and cytoskeleton remodeling. PGC1-α mRNA was down-regulated by FK506. MotifADE identified nuclear factor of activated T-cells, an important mediator of β-cell survival and function, as a potential factor mediating both up- and down-regulation of gene expression.

CONCLUSIONS

At pharmacologically relevant concentrations, FK506 decreases insulin secretion and reduces mitochondrial density and function without changing apoptosis rates, suggesting that posttransplantation diabetes induced by FK506 may be mediated by its effects on mitochondrial function.