Effects of kidney-pancreas transplantation on atherosclerotic risk factors and endothelial function in patients with uremia and type 1 diabetes

Hyperglycemia and Hyperlipidemia with Kidney or Liver Transplantation: A Review

Although solid organ transplantation in persons with diabetes mellitus is often associated with hyperglycemia, the risk of hyperlipidemia in all organ transplant recipients is often underestimated. The diagnosis of diabetes often predates transplantation; however, in a moderate percentage of allograft recipients, perioperative hyperglycemia occurs triggered by antirejection regimens. Post-transplant prescription of glucocorticoids, calcineurin inhibitors and mTOR inhibitors are associated with increased lipid concentrations. The existence of diabetes mellitus prior to or following a liver transplant is associated with shorter times of useful allograft function. A cycle involving Smad, TGF beta, m-TOR and toll-like receptors has been identified in the contribution of rejection and aging of allografts. Glucocorticoids (prednisone) and calcineurin inhibitors (cyclosporine and tacrolimus) induce hyperglycemia associated with insulin resistance. Azathioprine, mycophenolate and prednisone are associated with lipogenesis. mTOR inhibitors (rapamycin) are used to decrease doses of atherogenic agents used for immunosuppression. Post-transplant medication management must balance immune suppression and glucose and lipid control. Concerns regarding rejection often override those relative to systemic and organ vascular aging and survival. This review focuses attention on the underlying mechanism of relationships between glycemia/lipidemia control, transplant rejection and graft aging.

Pre-operative ankle-brachial index for cardiovascular risk assessment in simultaneous pancreas-kidney transplant recipients: a simple and elegant strategy!

Background

Patients with insulin-dependent diabetes mellitus type 1 (IDDM1) and end-stage kidney disease (ESKD) undergoing simultaneous pancreas kidney transplantation (SPKT) are a population with diffuse atherosclerosis and elevated risk of cardio- and cerebrovascular morbidity and mortality. We aimed to investigate the feasibility of preoperative screening for peripheral arterial disease (PAD), specifically ankle-brachial index (ABI) testing, to predict peri- and postoperative outcomes in SPKT recipients.

Methods

Medical data (2000–2016) from all patients with IDDM and ESKD undergoing SPKT at our transplant center were retrospectively analyzed. The correlation between PAD (defined by an abnormal ABI before SPKT and graft failure and mortality rates as primary end points, and the occurrence of acute myocardial infarction, cerebrovascular and peripheral vascular complications as secondary end points were investigated after adjustment for known cardiovascular risk factors.

Results

Among 101 SPKT recipients in our transplant population who underwent structured physiological arterial studies, 17 patients (17%) were diagnosed with PAD before transplantation. PAD, as defined by a low ABI index, was an independent and significant predictor of death (HR, 2.99 (95% CI 1.00–8.87), p = 0.049) and pancreas graft failure (HR, 4.3 (95% CI 1.24–14.91), p = 0.022). No significant differences were observed for kidney graft failure (HR 1.85 (95% CI 0.76–4.50), p = 0.178). In terms of the secondary outcomes, patients with PAD were more likely to have myocardial infarction, stroke, limb ischemia, gangrene or amputation (HR, 2.90 (95% CI 1.19–7.04), p = 0.019).

Conclusions

Pre-transplant screening for PAD and cardiovascular risk factors with non-invasive ABI testing may help to reduce perioperative complications in high-risk patients. Future research on long-term outcomes might provide more in depth insights in optimal treatment strategies for PAD among SPKT recipients.

Endothelial function after pancreas transplantation-A single-center observational study

BACKGROUND

Patients with diabetes mellitus treated with successful pancreas transplantation (PTX) normalize hyperglycemia, but are exposed to immunosuppressive drugs that may impair endothelial function. This study aimed to evaluate endothelial function in single PTX recipients.

METHODS

Flow-mediated dilatation (FMD) in the brachial artery was measured by ultrasound 8 weeks after transplantation in single PTX (n = 27) and compared with healthy controls (n = 58), simultaneous pancreas and kidney recipients (n = 9), and kidney transplant recipients with (n = 41) and without (n = 95) diabetes mellitus. Adjustments for age, gender, blood pressure, and body mass index were included in a linear regression model. Changes in FMD from before to 1 year after transplantation were assessed in a subgroup of PTX recipients (n = 9).

RESULTS

Flow-mediated dilatation% in PTX recipients was not inferior to healthy controls (8.7 ± 3.6 vs 7.7 ± 3.3, P = .06) and simultaneous pancreas and kidney recipients (6.7 ± 4.5, P = .24) in an adjusted model, and superior to kidney recipients with and without diabetes (3.0 ± 3.0 and 4.8 ± 3.3, respectively, both P < .005). FMD% improved significantly from eight weeks to one year after PTX, mean 7.9 ± 4.2% vs 11.8 ± 4.8% (N = 9; P = .03).

CONCLUSION

Flow-mediated dilatation is well preserved in patients undergoing pancreas transplantation and is not impaired when immunosuppressive drugs are introduced.

Citrate anion improves chronic dialysis efficacy, reduces systemic inflammation and prevents Chemerin-mediated microvascular injury

Systemic inflammation and uremic toxins (UT) determine the increased cardiovascular mortality observed in chronic hemodialysis (HD) patients. Among UT, the adipokine Chemerin induces vascular dysfunction by targeting both endothelial and vascular smooth muscular cells (EC and VSMC). As Citrate anion modulates oxidative metabolism, systemic inflammation and vascular function, we evaluated whether citrate-buffered dialysis improves HD efficiency, inflammatory parameters and chemerin-mediated microvascular injury. 45 patients were treated in sequence with acetate, citrate and, again, acetate-buffered dialysis solution (3 months per interval). At study admission and after each treatment switch, we evaluated dialysis efficacy and circulating levels of chemerin and different inflammatory biomarkers. In vitro, we stimulated EC and VSMC with patients’ plasma and we investigated the role of chemerin as UT. Citrate dialysis increased HD efficacy and reduced plasma levels of CRP, fibrinogen, IL6 and chemerin. In vitro, patients’ plasma induced EC and VSMC dysfunction. These effects were reduced by citrate-buffered solutions and paralleled by the decrease of chemerin levels. Consistently, chemerin receptor knockdown reduced EC and VSMC dysfunction. In conclusion, Switching from acetate to citrate improved dialysis efficacy and inflammatory parameters; in vitro, chemerin-induced EC and VSMC injury were decreased by using citrate as dialysis buffer.

Retrospective Analysis of Bone Metabolism in Patients on Waiting List for Simultaneous Pancreas-Kidney Transplantation

Posttransplant osteoporosis, which evolves from preexisting bone pathologies, represents a serious complication with deteriorating consequences. The aim of our study was to evaluate epidemiological data on bone mineral density (BMD) in subjects with type 1 diabetes (T1DM) in advanced stages of diabetic nephropathy indicated for simultaneous pancreas-kidney transplantation (SPK). We retrospectively compiled biochemical and densitometrical data from 177 patients with T1DM at CKD (chronic kidney disease) stages G4-G5 (115 men, 62 women, median age 40 yr, diabetes duration 23 yr) enrolled on waiting list for SPK for the first time between the years 2011 and 2016. Median Z-scores were as follows: lumbar spine (LS): -0.8 [interquartile range -1.75 to 0.1]; total hip (TH): -1.2 [-1.75 to -0.6]; femoral neck (FN): -1.2 [-1.9 to -0.7]; and distal radius (DR): -0.8 [-1.4 to -0.1]. We noted a gender difference in LS, with worse results for men (-1.1 vs. -0.3) even after adjusting for BMI (body mass index) and glomerular filtration (p < 0.001). Osteoporotic and osteopenic ranges (based on T-scores) for all major sites were 27.7% and 56.5%, respectively, with similar results across both genders. Women had a significantly higher proportion of normal BMD in LS than men (67.7 vs. 49.4%, p < 0.05). Patients with T1DM at CKD stages G4-G5 exhibited serious BMD impairment despite their young age. Men surprisingly displayed lower Z-scores and higher percentages of pathological BMD values in LS than women did. The introduction of adequate preventive measures during the advanced stages of diabetic nephropathy to prevent bone loss is recommended.

Pancreas Transplantation: Indications, Techniques, and Outcomes

Pancreas transplantation treats insulin-dependent diabetes with or without concurrent end-stage renal disease. Pancreas transplantation increases survival versus no transplant, increases survival when performed as simultaneous pancreas-kidney versus deceased-donor kidney alone, and improves quality of life. Careful donor and recipient selection are paramount to good outcomes. Several technical variations exist for implantation: portal versus systemic vascular drainage and jejunal versus duodenal versus bladder exocrine drainage. Complications are most frequently technical in the first year and immunologic thereafter. Graft rejection is challenging to diagnose and is treated selectively. Islet cell transplantation currently has inferior outcomes to whole-organ pancreas transplantation.

Renopancreatic Transplantation: Evaluation of 15 Years in 131 Patients

BACKGROUND

The most common multiple-organ transplant is the simultaneous pancreas-kidney transplantation (SPK). It is usually offered to patients who have insulin-dependent diabetes mellitus and those with diabetic nephropathy and renal failure that has already been established. In this study we present the results of 15 years of SPK in a transplant hospital center in Paraná, Brazil, and evaluated survival, immunosuppression, and transplant-related problems.

METHODS

This study was a retrospective analysis of 131 SPK transplants performed at the Angelina Caron Hospital between January 2001 and December 2015.

RESULTS

The mean age of SPK recipients was 34 years, with slight a predominance of males (50.4%). Mean graft ischemia time was 11 hours. Exocrine drainage was predominantly vesical, but this approach was abandoned after 2011. As for immunosuppression, induction was performed with basiliximab or thymoglobulin and maintained with prednisone, mycophenolate mofetil, tacrolimus, and/or sirolimus. Patient survival increased from 68.1% in 2001 to 2005 to 77.6% in 2011 to 2015. Graft survival at the end of the period was 85.7% for kidney and 75.5% for pancreas. The main surgery-derived problems for pancreas and kidney was thrombosis (15% and 6%, respectively). The main clinical problems were rejection of the pancreas (18.3%) and urinary infection of the kidney (33.3%). The main cause of death was intra-abdominal sepsis (11.4%).

CONCLUSION

There was an improvement in survival rates over the time frame observed, but it remains necessary to adopt measures to reduce transplant-derived problems, including review of the antibiotic therapy protocol and measures to avoid graft thrombosis.

Type 1 diabetic patients have better endothelial function after simultaneous pancreas-kidney transplantation than after kidney transplantation with continued insulin therapy

The purpose of this study was to analyse the influence of simultaneous pancreas-kidney or kidney transplantation on endothelial function and systemic inflammation in type 1 diabetic patients with end-stage renal disease. In 39 simultaneous pancreas-kidney, 39 type 1 diabetic kidney and 52 non-diabetic kidney recipients, flow-mediated dilatation was measured. Additionally, blood glycated haemoglobin, serum creatinine and lipids, plasma nitrites [Formula: see text] and nitrates, asymmetric dimethylarginine, soluble vascular cell adhesion molecule-1, intercellular adhesion molecule-1, and E-selectin, high-sensitivity C-reactive protein, tumour necrosis factor-α, interleukin 1β and interleukin 6 concentrations were assessed. During 58 ± 31 months follow-up period, flow-mediated dilatation and [Formula: see text] were greater in simultaneous pancreas-kidney than in type 1 diabetic kidney recipients [10.4% ± 4.7% vs 7.7% ± 4.2%, p < 0.05 and 0.94 (0.74-1.34) vs 0.24 (0.20-0.43) μmol/L, p < 0.01, respectively]. In type 1 diabetic patients after simultaneous pancreas-kidney or kidney transplantation, [Formula: see text] correlated with flow-mediated dilatation (r = 0.306, p < 0.05) and with blood glycated haemoglobin (r = -0.570, p < 0.001). The difference in [Formula: see text] was linked to blood glycated haemoglobin and estimated glomerular filtration rate, whereas the difference in flow-mediated dilatation was linked to [Formula: see text]. The levels of inflammatory markers (except soluble vascular cell adhesion molecule-1) were similar in simultaneous pancreas-kidney and type 1 diabetic kidney recipients. Improved endothelial function in type 1 diabetic patients with end-stage renal disease after simultaneous pancreas-kidney compared to kidney transplantation is associated with normalisation of glucose metabolism but not with improvement in plasma pro-inflammatory cytokines.

Cardiovascular disease and type 1 diabetes: prevalence, prediction and management in an ageing population

Cardiovascular disease (CVD) is a major cause of mortality in type 1 diabetes mellitus (T1D). However, evidence of its risks and management is often extrapolated from studies in type 2 diabetic (T2D) patients or the general population. This approach is unsatisfactory given that the underlying pathology, demographics and natural history of the disease differ between T1D and T2D. Furthermore, with a rising life expectancy, a greater number of T1D patients are exposed to the cardiovascular (CV) risk factors associated with an ageing population. The aim of this review is to examine the existing literature around CVD in T1D. We pay particular attention to CVD prevalence, how well we manage risk, potential biomarkers, and whether the studies included the older aged patients (defined as aged over 65). We also discuss approaches to the management of CV risk in the older aged. The available data suggest a significant CVD burden in patients with T1D and poor management of CV risk factors. This is underpinned by a poor evidence base for therapeutic management of CV risk specifically for patients with T1D, and in the most relevant population - the older aged patients. We would suggest that important areas remain to be addressed, particularly exploring the risks and benefits of therapeutic approaches to CVD management in the older aged.

Circulating IGF-I and IGFBP3 Levels Control Human Colonic Stem Cell Function and Are Disrupted in Diabetic Enteropathy

The role of circulating factors in regulating colonic stem cells (CoSCs) and colonic epithelial homeostasis is unclear. Individuals with long-standing type 1 diabetes (T1D) frequently have intestinal symptoms, termed diabetic enteropathy (DE), though its etiology is unknown. Here, we report that T1D patients with DE exhibit abnormalities in their intestinal mucosa and CoSCs, which fail to generate in vitro mini-guts. Proteomic profiling of T1D+DE patient serum revealed altered levels of insulin-like growth factor 1 (IGF-I) and its binding protein 3 (IGFBP3). IGFBP3 prevented in vitro growth of patient-derived organoids via binding its receptor TMEM219, in an IGF-I-independent manner, and disrupted in vivo CoSC function in a preclinical DE model. Restoration of normoglycemia in patients with long-standing T1D via kidney-pancreas transplantation or in diabetic mice by treatment with an ecto-TMEM219 recombinant protein normalized circulating IGF-I/IGFBP3 levels and reestablished CoSC homeostasis. These findings demonstrate that peripheral IGF-I/IGFBP3 controls CoSCs and their dysfunction in DE.

GTP cyclohydrolase I gene polymorphisms are associated with endothelial dysfunction and oxidative stress in patients with type 2 diabetes mellitus

BACKGROUND

The genetic background of atherosclerosis in type 2 diabetes mellitus (T2DM) is complex and poorly understood. Studying genetic components of intermediate phenotypes, such as endothelial dysfunction and oxidative stress, may aid in identifying novel genetic components for atherosclerosis in diabetic patients.

METHODS

Five polymorphisms forming two haplotype blocks within the GTP cyclohydrolase 1 gene, encoding a rate limiting enzyme in tetrahydrobiopterin synthesis, were studied in the context of flow and nitroglycerin mediated dilation (FMD and NMD), intima-media thickness (IMT), and plasma concentrations of von Willebrand factor (vWF) and malondialdehyde (MDA).

RESULTS

Rs841 was associated with FMD (p = 0.01), while polymorphisms Rs10483639, Rs841, Rs3783641 (which form a single haplotype) were associated with both MDA (p = 0.012, p = 0.0015 and p = 0.003, respectively) and vWF concentrations (p = 0.016, p = 0.03 and p = 0.045, respectively). In addition, polymorphism Rs8007267 was also associated with MDA (p = 0.006). Haplotype analysis confirmed the association of both haplotypes with studied variables.

CONCLUSIONS

Genetic variation of the GCH1 gene is associated with endothelial dysfunction and oxidative stress in T2DM patients.

Subclinical diastolic dysfunction in young adults with Type 2 diabetes mellitus: a multiparametric contrast-enhanced cardiovascular magnetic resonance pilot study assessing potential mechanisms

AIMS

To assess the cardiac, vascular, anthropometric, and biochemical determinants of subclinical diastolic dysfunction in younger adults with Type 2 diabetes mellitus (T2DM) using multiparametric contrast-enhanced cardiovascular magnetic resonance (CMR) imaging.

METHODS AND RESULTS

Twenty adults <40 years with T2DM [mean age 31.8(6.6) years, T2DM duration 4.7(4.0) years] and 20 age and sex-matched controls [10 obese non-diabetic controls and 10 lean controls (LC)] were studied. Cardiac volumes and function, circumferential strain and peak early diastolic strain rate (PEDSR), myocardial perfusion reserve, aortic stiffness (distensibility, pulse-wave velocity), focal fibrosis on late gadolinium enhancement, and pre- and post-contrast T1 mapping for contrast agent partition coefficient (subset, n = 26) were determined by CMR. In the T2DM cohort, mean aortic distensibility correlated with PEDSR (r = 0.564, P = 0.023) and diabetes duration correlated inversely with PEDSR (r = -0.534, P = 0.015) on univariate analysis. There was a close association between PEDSR and peak systolic strain (r = -0.580, P = 0.007).

CONCLUSION

In young adults with T2DM, diabetes duration and aortic distensibility were associated with diastolic dysfunction. Interventional studies are required to assess whether cardiac dysfunction can be reversed in this phenotype of patients.

Examination of carbohydrate metabolism parameters after simultaneous pancreas-kidney transplantation

End-stage renal failure, a frequent complication of type 1 diabetes mellitus, requires renal replacement therapy. Our team examined the laboratory parameters of carbohydrate metabolism in 18 patients with type 1 diabetes at 10 to 89 months after simultaneous pancreas-kidney transplantation. We compared these results with those of 17 patients with type 1 diabetes who had formerly received kidney-alone transplantations, and were undergoing insulin treatment, as well as with those of 16 metabolically healthy controls. The hemoglobin A1c (HbA1c) and blood glucose levels of the pancreas-kidney transplant recipients were within the normal ranges, not differing significantly from those of the healthy controls. In contrast, the HbA1c and glucose levels were significantly elevated among kidney transplanted diabetic subjects. However, fasting and 2-hour insulin levels of pancreas-kidney transplant patients were significantly higher than those of the controls, indicating insulin resistance. According to these results, the insulin secretion by the pancreas graft sufficiently compensated for insulin resistance. Thus 10 to 89 months after successful pancreas-kidney transplantation, carbohydrate metabolism by type 1 diabetic patients was well controlled without antidiabetic therapy.

Follow-up of secondary diabetic complications after pancreas transplantation

PURPOSE OF REVIEW

Successful pancreas transplantation restores physiologic glycemic and metabolic control. Its effects on overall patient survival (especially for simultaneous pancreas-kidney transplantation) are clear-cut. We herein review the available literature to define the impact of pancreas transplantation on chronic complications of diabetes mellitus.

RECENT FINDINGS

With longer-term follow-up, wider patient populations, and more accurate investigational tools (clinical and functional tests, noninvasive imaging, histology, and molecular biology), growing data show that successful pancreas transplantation may slow the progression, stabilize, and even favor the regression of secondary complications of diabetes, both microvascular and macrovascular, in a relevant proportion of recipients.

SUMMARY

Patients who are referred for pancreas transplantation usually suffer from advanced chronic complications of diabetes, which have classically been deemed irreversible. A successful pancreas transplantation is often able to slow the progression, stabilize, and even reverse many microvascular and macrovascular complications of diabetes. Growing clinical evidence shows that the expected natural history of long-term diabetic complications can be significantly modified by successful pancreas transplantation.

Transplantation of the pancreas

Pancreas transplantation consistently induces insulin-independence in beta-cell-penic diabetic patients, but at the cost of major surgery and life-long immunosuppression. One year after grafting, patient survival rate now exceeds 95 % across recipient categories, while insulin independence is maintained in some 85 % of simultaneous pancreas and kidney recipients and in nearly 80 % of solitary pancreas transplant recipients. The half-life of the pancreas graft currently averages 16.7 years, being the longest among extrarenal grafts, and substantially matching the one of renal grafts from deceased donors. The difference between expected (100 %) and actual insulin-independence rate is mostly explained by technical failure in the postoperative phase, and rejection in the long-term period. Death with a functioning graft remains a further major issue, especially in uremic patients who have undergone prolonged periods of dialysis. Refinements in graft preservation, surgical techniques, immunosuppression, and prophylactic treatments are expected to further improve the results of pancreas transplantation.

Immunological applications of stem cells in type 1 diabetes

Current approaches aiming to cure type 1 diabetes (T1D) have made a negligible number of patients insulin-independent. In this review, we revisit the role of stem cell (SC)-based applications in curing T1D. The optimal therapeutic approach for T1D should ideally preserve the remaining β-cells, restore β-cell function, and protect the replaced insulin-producing cells from autoimmunity. SCs possess immunological and regenerative properties that could be harnessed to improve the treatment of T1D; indeed, SCs may reestablish peripheral tolerance toward β-cells through reshaping of the immune response and inhibition of autoreactive T-cell function. Furthermore, SC-derived insulin-producing cells are capable of engrafting and reversing hyperglycemia in mice. Bone marrow mesenchymal SCs display a hypoimmunogenic phenotype as well as a broad range of immunomodulatory capabilities, they have been shown to cure newly diabetic nonobese diabetic (NOD) mice, and they are currently undergoing evaluation in two clinical trials. Cord blood SCs have been shown to facilitate the generation of regulatory T cells, thereby reverting hyperglycemia in NOD mice. T1D patients treated with cord blood SCs also did not show any adverse reaction in the absence of major effects on glycometabolic control. Although hematopoietic SCs rarely revert hyperglycemia in NOD mice, they exhibit profound immunomodulatory properties in humans; newly hyperglycemic T1D patients have been successfully reverted to normoglycemia with autologous nonmyeloablative hematopoietic SC transplantation. Finally, embryonic SCs also offer exciting prospects because they are able to generate glucose-responsive insulin-producing cells. Easy enthusiasm should be mitigated mainly because of the potential oncogenicity of SCs.

Evolution of β-Cell Replacement Therapy in Diabetes Mellitus: Pancreas Transplantation

Diabetes mellitus remains one of the leading causes of morbidity and mortality worldwide. According to the Centers for Disease Control and Prevention, approximately 23.6 million people in the United States are affected. Of these individuals, 5-10% have been diagnosed with type 1 diabetes mellitus (TIDM), an autoimmune disease. Although it often appears in childhood, T1DM may manifest at any age. The effects of T1DM can be devastating, as the disease often leads to significant secondary complications, morbidity, and decreased quality of life. Since the late 1960s, surgical treatment for diabetes mellitus has continued to evolve and has become a viable alternative to chronic insulin administration. In this review, the historical evolution, current status, graft efficacy, benefits, and complications of pancreas transplantation are explored.

Islet versus pancreas transplantation in type 1 diabetes: competitive or complementary?

Whole organ pancreas and pancreatic islet transplantation are currently the only forms of clinically available β-cell replacement. Both therapeutic options can provide good glycemic control and prevention or stabilization of diabetic complications, but at the price of permanent immunosuppression. Therefore, the indication for transplantation of type 1 diabetes patients must be balanced carefully and should be restricted to a subgroup of patients with extreme lability of metabolic control and frequent hypoglycemia despite optimal medical therapy.

Transplantation in diabetic kidney failure patients: modalities, outcomes, and clinical management

Diabetes mellitus (DM) is a common and devastating disease, affecting up to 19.3 million Americans. It is the leading cause of chronic kidney disease (CKD) and end-stage renal disease (ESRD) in the United States. Diabetic patients with ESRD have a high incidence of cardiovascular disease and death. For those kidney transplant patients with no history of DM prior to transplantation, the development of new onset diabetes after transplantation (NODAT) also poses a serious threat to both graft and patient survival. Kidney transplantation is the best renal replacement option for diabetic ESRD and has the potential to halt the progression of cardiovascular diseases. Early referral for transplant evaluation is essential for pre-emptive or early kidney transplantation in this cohort of patients. In type 1 DM patients with ESRD, simultaneous pancreas and kidney transplantation (SPK) should be encouraged; and in patients facing prolonged waiting time for SPK transplantation but with an available living donor, living donor kidney transplantation followed by pancreas after kidney transplantation (PAK) is a suitable alternative. Islet transplantation in type 1 diabetics is deemed experimental by Medicare, and easy access to this modality remains restricted to qualified patients enrolled in clinical trials or with private insurance. The optimal management of kidney transplant patients with pre-existent DM or NODAT involves a multi-pronged approach consisting of pharmacological and nonpharmacological intervention to address all potential cardiovascular risk factors such as glycemic and lipid control, blood pressure control, weight loss, and smoking cessation. Finally, re-transplantation should be recommended in suitable kidney transplant patients when the kidney allograft demonstrates continuous and progressive decline in function.

Proteomics reveals novel oxidative and glycolytic mechanisms in type 1 diabetic patients' skin which are normalized by kidney-pancreas transplantation

BACKGROUND

In type 1 diabetes (T1D) vascular complications such as accelerated atherosclerosis and diffused macro-/microangiopathy are linked to chronic hyperglycemia with a mechanism that is not yet well understood. End-stage renal disease (ESRD) worsens most diabetic complications, particularly, the risk of morbidity and mortality from cardiovascular disease is increased several fold.

METHODS AND FINDINGS

We evaluated protein regulation and expression in skin biopsies obtained from T1D patients with and without ESRD, to identify pathways of persistent cellular changes linked to diabetic vascular disease. We therefore examined pathways that may be normalized by restoration of normoglycemia with kidney-pancreas (KP) transplantation. Using proteomic and ultrastructural approaches, multiple alterations in the expression of proteins involved in oxidative stress (catalase, superoxide dismutase 1, Hsp27, Hsp60, ATP synthase delta chain, and flavin reductase), aerobic and anaerobic glycolysis (ACBP, pyruvate kinase muscle isozyme, and phosphoglycerate kinase 1), and intracellular signaling (stratifin-14-3-3, S100-calcyclin, cathepsin, and PPI rotamase) as well as endothelial vascular abnormalities were identified in T1D and T1D+ESRD patients. These abnormalities were reversed after KP transplant. Increased plasma levels of malondialdehyde were observed in T1D and T1D+ESRD patients, confirming increased oxidative stress which was normalized after KP transplant.

CONCLUSIONS

Our data suggests persistent cellular changes of anti-oxidative machinery and of aerobic/anaerobic glycolysis are present in T1D and T1D+ESRD patients, and these abnormalities may play a key role in the pathogenesis of hyperglycemia-related vascular complications. Restoration of normoglycemia and removal of uremia with KP transplant can correct these abnormalities. Some of these identified pathways may become potential therapeutic targets for a new generation of drugs.

Persistent arterial stiffness and endothelial dysfunction following successful pancreas-kidney transplantation in Type 1 diabetes

OBJECTIVE

Successful simultaneous pancreas-kidney transplantation (SPK) in Type 1 diabetic (T1DM) patients results in improved cardiovascular outcome and survival. However, it is doubtful whether the impairment of cardiovascular and endothelial function in T1DM can be completely reversed.

METHODS

Pulse-wave velocity, stroke volume, heart rate, serological markers of endothelial dysfunction (soluble intercellular, vascular cell-adhesion molecules, E-selectin, and plasminogen-activator-inhibitor-1) were measured in 10 T1DM patients after SPK with non-diabetic glucose levels, 10 T1DM patients with poor [T1DM>8; glycated haemoglobin (HbA1c)>8%], and 10 with good glucose control (T1DM<7, HbA1c<7%), in 6 non-diabetic patients after kidney transplantation (KT) and 9 non-diabetic control subjects (CON), matching for major anthropometric characteristics.

RESULTS

Pulse-wave velocity was increased in SPK (P < 0.02 vs. CON, KT, T1DM<7) and in T1DM>8 (P < 0.02 vs. T1DM<7). Systolic blood pressure was increased in SPK (P < 0.05 vs. CON). Stroke volume was reduced in SPK, T1DM>8 and T1DM<7 and KT (P < 0.01 vs. CON). Heart rate was elevated in SPK and in T1DM>8 (P < 0.0003 vs. CON and T1DM<7). In SPK, soluble intercellular and vascular cell-adhesion molecules were 100% and 44% higher (P < 0.03 vs. CON), respectively, while plasminogen-activator-inhibitor-1 was decreased in SPK (P < 0.02 vs. CON).

CONCLUSION

T1DM patients after SPK experience arterial stiffness, a higher heart-rate and blood pressure, reduced stroke volume and serological signs of endothelial dysfunction. Thus, functional and structural cardiovascular alterations as a result of glucotoxicity, uraemia and hypertension in T1DM might not be completely resolved by SPK.

Simultaneous pancreas kidney transplantation: a critical appraisal of the risks and benefits compared with other treatment alternatives

Advances in technical aspects of pancreas transplantation and improvements in immunosuppression over the last decade have led to significant improvements in pancreas transplant outcomes in the short-term. Simultaneous kidney pancreas transplantation remains an attractive option for patients with type 1 diabetes (T1DM) and late chronic kidney disease (CKD), with 1-year pancreas graft survival rates of 86% in 2004. For the individual patient with T1DM and CKD, the various transplant options must be considered carefully, with attention to the timing of surgery relative to the need for dialysis, the challenge in managing diabetes with noninvasive medical therapy, and the assumption of risks attendant to each surgical option. This review summarizes the current status of simultaneous pancreas kidney transplantation and compares and contrasts outcomes with other potential treatment options.

Twelve-month pancreas graft function significantly influences survival following simultaneous pancreas-kidney transplantation

BACKGROUND AND OBJECTIVES

Simultaneous pancreas-kidney transplantation (SPK) is regarded as the treatment of choice for type 1 diabetes (T1DM) and kidney dysfunction, despite the morbidity associated with pancreas transplantation. These morbidities often influence selection of SPK versus living-donor kidney alone (LD KA) transplant. This study quantifies the impact of pancreas graft function on outcomes following SPK.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Using the SRTR database, SPK wait-listed patients transplanted from 1997 to 2005 were evaluated and segregated as: (1) SPK recipients with functioning pancreas graft 12 mo posttransplant (SPK, P+); (2) SPK recipients with loss of pancreas graft function within 12 mo posttransplant (SPK, P-); (3) recipients of deceased donor (DD) KA; (4) recipients of LD KA. The study compared patient and kidney graft survival to 84 mo posttransplant.

RESULTS

Patient survival for SPK, P+ was significantly better than the LD KA; SPK, P-; and DD KA cohorts (88.6% versus 80.0%, 73.9% and 64.8%, respectively [P < 0.001]), a finding confirmed by multivariate analysis and not influenced by pancreas-after-kidney transplantation (PAK) rates and outcomes. Unadjusted graft survival was also highest in the SPK, P+ cohort (72.0% versus 63.6%, 59.8%, 49.7%, P = 0.015 versus LD KA).

CONCLUSIONS

SPK recipients with functioning pancreas grafts have superior survival compared with LD KA and DD KA, including in the setting of PAK. Early pancreas graft failure results in kidney and patient survival rates similar to KA. These data help further clarify the decision-making of SPK versus KA transplant options for patients and providers.

The impact of functioning pancreas-kidney transplantation and pancreas alone transplantation on the lipid metabolism of statin-naïve diabetic patients

OBJECTIVE

To compare the lipid profile (total cholesterol - TC, triglycerides - TG, high density lipoprotein cholesterol - HDL-c, low density lipoprotein cholesterol - LDL-c and non-HDL cholesterol - NHDL-c) of patients with functioning pancreas-kidney transplantation (PKT) or pancreas transplantation alone (PTA) after one (T1) and two yr (T2) following their pre-transplantation data (T0).

METHODS

Fifty-three type 1 diabetic patients underwent pancreas transplantation (42 PKT and 11 PTA) remaining euglycemic after transplantation were evaluated before and one and two yr after the procedures. They were using predominantly tacrolimus-mycophenolate mofetil-based immunosuppression and low glucocorticoid dose with systemic venous drainage of the pancreatic graft. None of them used hypolipidemic agents for economical reasons. Lipids were reported as means +/- standard error of the mean. Data obtained in T0 were compared with T1 and T2 using ANOVA followed by Student's t-test.

RESULTS

TC, LDL-c, NHDL-c and TG were lower in T1 and T2 when compared with T0 (p < 0.05) in PKT, while no change was observed for HDL-c (p > 0.05). PTA group showed no significant changes in lipids.

CONCLUSION

In spite of the known side effects of tacrolimus-based immunosuppression to lipids, our study with a statin-naïve sample showed improvements (PKT) or stabilization (PTA) in the serum lipid profile after pancreas transplantation.

Long-term benefits of pancreas transplantation

PURPOSE OF REVIEW

Pancreas transplantation has emerged as an effective treatment for patients with diabetes mellitus, especially those with established end-stage renal disease. Surgical and immunosuppressive advances have significantly improved allograft survival. With more recipients enjoying normoglycemia for longer periods of time, the opportunity to study more closely the effects of pancreas transplantation has arisen. This review will focus on these long-term benefits.

RECENT FINDINGS

The field of pancreas transplantation has been limited by a lack of randomized, controlled trials and relatively poor graft survival rates historically, however we can still glean many important points from the existing literature. The procedure reduces mortality compared with diabetic kidney transplant recipients and waitlisted patients. Improvements in diabetic nephropathy and retinopathy have also been demonstrated. Pancreas transplantation can improve cardiovascular risk profiles, improve cardiac function and decrease cardiovascular events. Lastly, improvements in diabetic neuropathy and quality of life can result from pancreas transplantation.

SUMMARY

Pancreas transplantation remains the most effective method to establish durable normoglycemia for patients with diabetes mellitus. Well designed clinical studies to assess outcomes and adverse events will be of paramount importance in providing optimal care to patients with diabetes mellitus.

Evaluation of polyneuropathy markers in type 1 diabetic kidney transplant patients and effects of islet transplantation: neurophysiological and skin biopsy longitudinal analysis

OBJECTIVE

The purpose of this study was to evaluate whether islet transplantation may stabilize polyneuropathy in uremic type 1 diabetic patients (end-stage renal disease [ESRD] and type 1 diabetes), who received a successful islet-after-kidney transplantation (KI-s).

RESEARCH DESIGN AND METHODS

Eighteen KI-s patients underwent electroneurographic tests of sural, peroneal, ulnar, and median nerves: the nerve conduction velocity (NCV) index and amplitudes of both sensory action potentials (SAPs) and compound motor action potentials (CMAPs) were analyzed longitudinally at 2, 4, and 6 years after islet transplantation. Skin content of advanced glycation end products (AGEs) and expression of their specific receptors (RAGE) were also studied at the 4-year follow-up. Nine patients with ESRD and type 1 diabetes who received kidney transplantation alone (KD) served as control subjects.

RESULTS

The NCV score improved in the KI-s group up to the 4-year time point (P = 0.01 versus baseline) and stabilized 2 years later, whereas the same parameter did not change significantly in the KD group throughout the follow-up period or when a cross-sectional analysis between groups was performed. Either SAP or CMAP amplitudes recovered in the KI-s group, whereas they continued worsening in KD control subjects. AGE and RAGE levels in perineurium and vasa nervorum of skin biopsies were lower in the KI-s than in the KD group (P < 0.01 for RAGE).

CONCLUSIONS

Islet transplantation seems to prevent long-term worsening of polyneuropathy in patients with ESRD and type 1 diabetes who receive islets after kidney transplantation. No statistical differences between the two groups were evident on cross-sectional analysis. A reduction in AGE/RAGE expression in the peripheral nervous system was shown in patients receiving islet transplantation.

Impact of simultaneous pancreas and kidney transplantation on cardiovascular risk factors in patients with type 1 diabetes mellitus

We retrospectively investigated the impact of pancreas transplantation on cardiovascular disease risk factors in patients with type 1 diabetic end-stage renal disease (ESRD). Two cohorts of patients, 44 simultaneous pancreas and kidney transplant patients (SPK) and 30 kidney transplant-alone patients (KTA), were included. Univariate and multivariate analyses were performed. Compared with KTA patients, SPK patients had significantly lower mean arterial pressure (88.5+/-12.7 vs. 98.2+/-13.0 mmHg, P=0.002), lower pulse pressure (51.6+/-15.1 vs. 61.4+/-15.6 mmHg, P=0.008), lower low-density lipoprotein cholesterol (83.5+/-20.6 vs. 99.2+/-32.5 mg/dl, P=0.02), and required fewer lipid-lowering medications (31.8% vs. 60.0%, P=0.02). Compared with pretransplant values, only SPK patients showed significant improvement in both blood pressure and total cholesterol. We conclude that SPK significantly improves blood pressure and dyslipidemia compared with KTA in type 1 diabetic ESRD patients.

The long-term management of pancreas transplantation

Diabetes mellitus (DM) is a major health problem worldwide, which affects 18.2 million individuals (6.3% of the population) in the United States. Currently, the prevalence of Type 1 DM in the United States is estimated to be 1,000,000 individuals, and 30,000 new cases are diagnosed each year. In addition to end-stage renal disease (ESRD), DM is associated with blindness, accelerated atherosclerosis, dyslipidemia, cardio- and cerebrovascular disease, amputation, poor quality of life, and overall lifespan reduction. It accounts for more than 160,000 deaths per year in the United States alone. In 2002, the annual national direct and indirect costs of Types 1 and 2 DM exceeded $130 billion, which included hospital and physician care, laboratory tests, pharmaceutical products, and patient workdays lost because of disability or premature death. Hyperglycemia alone or in concert with hypertension is the primary factor influencing the development of major diabetic complications. From 1990 to 2001, the number of existing ESRD cases to DM increased by more than 300%, while the rate per million populations increased from 167% to 491%. The number is expected to grow 10-fold by 2030 to 1.3 million accounting for 60% of ESRD population. To date, DM is the leading indication for transplantation and is the cause of ESRD in more than 40% of all transplant recipients each year.

Quality of life after organ transplantation in type 1 diabetics with end-stage renal disease

Quality of life (QOL) should be an important consideration while choosing therapeutic options for patients with type 1 diabetes mellitus (DM) and end-stage renal disease (ESRD) including dialysis, cadaver (CKT) or living kidney transplant (LKT) or simultaneous pancreas-kidney (SPK) transplant.

METHODS

QOL was assessed in four groups of patients with history of type 1 DM and ESRD: recipients of SPK (n = 43), CKT (n = 43), LKT (n = 11) and wait listed (WL) patients (n = 23). Diabetes Quality of Life (DQOL), Short Form-36 (SF-36) and Quality of Well-Being (QWB) questionnaires were utilized. A subset of SPK (n = 19) and CKT (n = 12) recipients underwent longitudinal QOL evaluation.

RESULTS

On DQOL questionnaire, SPK group had better satisfaction subscore compared with CKT (1.8 +/- 0.5 vs. 2.2 +/- 0.6, p < 0.01) LKT (1.8 +/- 0.5 vs. 2.4 +/- 0.7, p < 0.05) and WL (1.8 +/- 0.5 vs. 2.6 +/- 0.6, p < 0.001) groups and better impact subscore compared with CKT (1.7 +/- 0.6 vs. 2.1 +/- 0.6, p < 0.05) and WL (1.7 +/- 0.6 vs. 2.3 +/- 0.6, p < 0.01) groups. There were no significant differences on physical/mental composite scores of SF-36. QWB score was better in SPK group vs. WL group (0.62 +/- 0.11 vs. 0.55 +/- 0.04, p < 0.05). Longitudinal decline in satisfaction (2.3 +/- 0.5 vs. 2.6 +/- 0.9, p = 0.058) and impact (2.0 +/- 0.5 vs. 2.2 +/- 0.5, p = 0.019) subscores of DQOL were noted in CKT group. There were no significant changes in the composite scores of SF-36 in both groups. QWB scores declined in the CKT group (0.67 +/- 0.10 vs. 0.61 +/- 0.05, p = 0.01).

CONCLUSION

QOL was better in type 1 diabetics with ESRD following transplantation when compared with remaining on WL. SPK transplantation had significant positive effect on diabetes-related QOL which was sustained longitudinally but it was difficult to show an overall improvement in general QOL.

The effect of whole organ pancreas transplantation and PIT on diabetic complications

Diabetes mellitus is a leading cause of morbidity and mortality in the Western world. Currently, the only forms of beta-cell replacement are whole organ pancreas transplantation and pancreatic islet transplantation. Whole organ transplantation has demonstrated benefits in prevention and reversal of diabetic complications with sustainable long-term outcomes. Pancreatic islet transplantation continues to be a field that needs further study to ascertain the true benefit of islet transplantation for diabetic complications. This can only be achieved with improvement in long-term islet allograft survival.

Simultaneous Pancreas-Kidney Transplantation: Five-Year Results From a Single Center

We report the 5-year results of our simultaneous pancreas-kidney transplantation (SPKT) program, started on May 2, 2000. Forty-two SPKT were performed on 42 type I diabetic patients with chronic renal failure. The procedure was performed with enteric diversion and vascular anastomosis to the iliac vessels. Immunosuppressive protocol included antithymocyte globulin, tacrolimus, mycophenolate mofetil, and steroids. The 24 women and 18 men had a mean age of 33.5 +/- 6.3 years and mean 22.8 +/- 14.2 years time of diabetes evolution. Forty patients had been on dialysis for 34.3 +/- 24.1 months, and two were preemptive transplantations. Acute rejection episodes were treated in eight patients (19.1%): in three cases they affected both organs; in two only the kidney was affected; and the other three were pancreas graft rejections. The incidence of postoperative complications requiring re-operation was 42.9%, mostly pancreas graft related. Two patients died, one due to cardiovascular disease; the other was transplant related. Three kidney grafts were lost, and the causes were immunologic, thrombosis, and patient death. Pancreas graft loss occurred in seven patients: thrombosis (n = 3); infection (n = 3); immunologic (n = 1). The patients with surviving grafts were doing well, with normal kidney and pancreas function: serum creatinine = 0.89 +/- 0.15 mg/dL; fasting blood glucose = 79 +/- 16 mg/dL; HbA1c = 4.7 +/- 1.1%. The 1-year patient, kidney, and pancreas survival rates were 97.3%, 94.6%, and 83.8% and 5-year values, 91.7%, 89.2%, and 78.7%, respectively. In conclusion, these results are similar to the most recent UNOS/IPTR reports, leading us to consider our experience with SPKT very positive.

Cross-sectional assessment of the effect of kidney and kidney-pancreas transplantation on resting left ventricular energy metabolism in type 1 diabetic-uremic patients: a phosphorous-31 magnetic resonance spectroscopy study

OBJECTIVES

To test whether left ventricular (LV) dysfunction affecting type 1 diabetic-uremic patients was associated with abnormal heart high-energy phosphates (HEPs) and to ascertain whether these alterations were also present in recipients of kidney or kidney-pancreas transplantation.

BACKGROUND

Heart failure is the major determinant of mortality in patients with diabetic uremia. Both uremia and diabetes induce alterations of cardiac HEPs metabolism.

METHODS

Magnetic resonance imaging and phosphorous magnetic resonance spectroscopy of the LV were performed in the resting state by means of a 1.5-T clinical scanner. Eleven diabetic-uremic patients, 5 nondiabetic patients with uremia, 11 diabetic recipients of kidney transplantation, and 16 diabetic recipients of combined kidney-pancreas transplantation were studied in a cross-sectional fashion. Eleven nondiabetic recipients of kidney-only transplant and 13 healthy subjects served as control groups.

RESULTS

Uremic patients had higher LV mass, diastolic dysfunction, and lower phosphocreatine (PCr)/adenosine triphosphate (ATP) ratio in comparison with recipients of kidney-pancreas or nondiabetic recipients of kidney transplant. In diabetic recipients of kidney transplant the PCr/ATP ratio was higher than in uremic patients but was lower than in the controls. Recipients of combined kidney-pancreas transplant had a higher ratio than uremic patients but no difference was found in comparison with controls.

CONCLUSIONS

Altered resting myocardial HEPs metabolism may contribute to LV dysfunction in diabetic-uremic patients. In diabetic recipients of kidney transplantation, a certain degree of LV metabolic and functional impairment was found. In combined kidney-pancreas recipients the resting LV metabolism and function were not different than in controls.

Improved Cardiovascular Risk Profile of Patients With Type 1 Diabetes Mellitus and Renal Failure After Simultaneous Pancreas–Kidney Transplantation

INTRODUCTION

The prognosis of patients with type 1 diabetes mellitus and chronic renal failure improves after simultaneous pancreas-kidney (SPK) transplantation. Good control of glycemia and other cardiovascular risk factors may positively influence prognosis. The objective of this study was to evaluate changes in cardiovascular risk factors after SKP.

PATIENTS AND METHODS

We studied 13 patients (aged 36 +/- 8 years, 7 women) before and 12 months after SPK transplantation. All were treated with thymoglobulin, prednisone, tacrolimus, and mycophenolate mofetil. We compared the following pre- and post-SPK parameters: glycemia, HbA(1)c, total cholesterol, HDL, LDL, triglycerides, systolic (sBP), diastolic blood pressure (dBP), and body mass index (BMI).

RESULTS

Twelve months after SPK transplantation, glycemia, HbA(1)c and triglycerides significantly decreased (P < .001; P < .001, and P < .002, respectively), as did sBP (P < .002) and dBP (P < .001). No changes were found for BMI or total, HDL and LDL cholesterol values. The number of patients requiring antihypertensive therapy fell (13 versus 3; P < .002), as did the number of drugs (2.3 +/- 0.8 versus 0.4 +/- 0.7; P < .001). The number of patients requiring statins also fell (11 versus 3; P < .002). At 12 months, all patients had normal renal function (creatinine clearance 85 +/- 10 mL/min) and required no insulin; four had microalbuminuria.

CONCLUSION

These interim results show an improved cardiovascular risk profile 12 months after SPK transplantation, which lays the basis for a more favorable long-term prognosis.

Islet transplantation is associated with an improvement of cardiovascular function in type 1 diabetic kidney transplant patients

OBJECTIVE

Cardiovascular mortality and morbidity are major problems in type 1 diabetic patients with end-stage renal disease (ESRD). The aim of this study was to determine whether islet transplantation can improve cardiovascular function in these patients.

RESEARCH DESIGN AND METHODS

We assessed various markers of cardiac function at baseline and 3 years later in a population of 42 type 1 diabetic patients with ESRD who received a kidney transplant. Seventeen patients then received an islet transplant that had persistent function as defined by long-term C-peptide secretion (kidney-islet group). Twenty-five patients did not receive a functioning islet transplant (kidney-only group).

RESULTS

GHb levels were similar in the two groups, whereas the exogenous insulin requirement was lower in the kidney-islet group with persistent C-peptide secretion. Overall, cardiovascular parameters improved in the kidney-islet group, but not in the kidney-only group, with an improvement of ejection fraction (from 68.2 +/- 3.5% at baseline to 74.9 +/- 2.1% at 3 years posttransplantation, P < 0.05) and peak filling rate in end-diastolic volume (EDV) per second (from 3.87 +/- 0.25 to 4.20 +/- 0.37 EDV/s, P < 0.05). Time to peak filling rate remained stable in the kidney-islet group but worsened in the kidney-only group (P < 0.05). The kidney-islet group also showed a reduction of both QT dispersion (53.5 +/- 4.9 to 44.6 +/- 2.9 ms, P < 0.05) and corrected QT (QTc) dispersion (67.3 +/- 8.3 to 57.2 +/- 4.6 ms, P < 0.05) with higher erythrocytes Na(+)-K(+)-ATPase activity. In the kidney-islet group only, both atrial natriuretic peptide and brain natriuretic peptide levels decreased during the follow-up, with a stabilization of intima-media thickness.

CONCLUSIONS

Our study showed that type 1 diabetic ESRD patients receiving a kidney transplant and a functioning islet transplant showed an improvement of cardiovascular function for up to 3 years of follow-up compared with the kidney-only group, who experienced an early failure of the islet graft or did not receive an islet graft.

Gastrointestinal bleeding from enterically drained transplanted pancreas

Gastrointestinal bleeding has been described as related complication of pancreas transplantation. Of 166 simultaneous pancreas kidney transplantations, 61 were enteric-drained pancreas transplants (eight done with and 53 without Roux-en-Y loop). The patients were divided into two groups according to Roux (group I, n = 8) or no Roux (group II, n = 53) technique. Seven patients experienced anastomotic hemorrhage between the jejunum and duodenal stump (11%), five cases in group I and two in group II (P < 0.001). No relationships between gastrointestinal bleeding duodenal stump and recipient jejunum blood flow, mean pancreatic cold ischemia time, platelet count, and prothrombin time were observed. Donor age over 40 years and abnormal activated partial thromboplastin time constituted risk factors for hemorrhage from the duodenojejunal anastomosis. There were no significant differences in pancreas graft and patient survival rates between the two groups. Anastomotic hemorrhage did not influence patient and graft survival.

Pancreas transplantation: indications and consequences

Pancreas transplantation continues to evolve as a strategy in the management of diabetes mellitus. The first combined pancreas-kidney transplant was reported in 1967, but pancreas transplant now represents a number of procedures, each with different indications, risks, benefits, and outcomes. This review will summarize these procedures, including their risks and outcomes in comparison to kidney transplantation alone, and how or if they affect the consequences of diabetes: hyperglycemia, hypoglycemia, and microvascular and macrovascular complications. In addition, the new risks introduced by immunosuppression will be reviewed, including infections, cancer, osteoporosis, reproductive function, and the impact of immunosuppression medications on blood pressure, lipids, and glucose tolerance. It is imperative that an endocrinologist remain involved in the care of the pancreas transplant recipient, even when glucose is normal, because of the myriad of issues encountered post transplant, including ongoing management of diabetic complications, prevention of bone loss, and screening for failure of the pancreas graft with reinstitution of treatment when indicated. Although long-term patient and graft survival have improved greatly after pancreas transplant, a multidisciplinary team is needed to maximize long-term quality, as well as quantity, of life for the pancreas transplant recipient.

Normalization of multiple hemostatic abnormalities in uremic type 1 diabetic patients after kidney-pancreas transplantation

To evaluate the effects of kidney-pancreas transplantation on hemostatic abnormalities in uremic type 1 diabetic patients, we conducted a cross-sectional study involving 12 type 1 diabetic patients, 30 uremic type 1 diabetic patients, 27 uremic type 1 diabetic patients who had a kidney-pancreas transplant, 12 uremic type 1 diabetic patients who had a kidney-alone transplant, and 13 healthy control subjects. We evaluated platelet and clotting system. Platelets in the group of uremic type 1 diabetic patients were significantly larger than platelets in the other groups. Resting calcium levels were significantly higher in the uremic type 1 diabetic patients and uremic type 1 diabetic patients who had a kidney-alone transplant than in the type 1 diabetic patients who had a kidney-pancreas transplant and control subjects. CD41 expression was significantly reduced in platelets from the uremic type 1 diabetic patients compared with the other groups. Levels of hypercoagulability markers in the type 1 diabetic patients who had a kidney-pancreas transplant and, to a lesser extent, the uremic type 1 diabetic patients who had a kidney-alone transplant but not the uremic type 1 diabetic patients were similar to those of the control subjects. A reduction in natural anticoagulants was evident in the uremic type 1 diabetic patients, whereas near-normal values were observed in the type 1 diabetic patients who had a kidney-pancreas transplant and uremic type 1 diabetic patients who had a kidney-alone transplant. Hemostatic abnormalities were not observed in type 1 diabetic patients who had a kidney-pancreas transplant. This finding might explain the lower cardiovascular death rate observed in type 1 diabetic patients who had a kidney-pancreas transplant compared with uremic type 1 diabetic patients who had a kidney-alone transplant or uremic type 1 diabetic patients.

Risks and side effects of islet transplantation

Islet transplantation can deliver stable glycemic control, relief from recurrent severe hypoglycemia, and insulin independence. Accessing the portal vein via the percutaneous hepatic approach carries the risk of bleeding, and the infusion of islets a risk of portal vein thrombosis. In the long term, common minor problems with immunosuppression are mouth ulcers, diarrhea, and acne. Longer-term risks include malignancy and serious infection, both rare to date in clinical islet transplantation. Sensitization to donor antigens may also occur. The long-term diabetes complications may stabilize, but of this aspect little is known to date. In the short term, there may be some elevation of serum cholesterol and blood pressure, in some patients there has been a decline in renal function, and in a few, acute retinal bleeds. For most, improvement in glucose control with resolution of glycemic lability and hypoglycemia has been a net benefit.

[Pancreatic transplantation: 1. Indications and results]

In the face of a rising incidence of diabetes, pancreatic transplantation seems to be the only treatment capable of normalizing glycosylated hemoglobin and stabilizing or improving the complications of diabetes. To date, more than 19,000 pancreatic transplantations have been done worldwide. Surgical indications must take into account the constraints and risks specific to the diabetic illness, the risks of a complex surgical procedure, and the absolute necessity for long term immunosuppression. Combined kidney/pancreas transplantation is the most common procedure (90% of cases) and is the most effective treatment for renal insufficiency due to diabetes. Results have improved significantly over the last ten Years due to improvements in the surgical technique and to improvement of immunosuppressive regimens. Results are at least as good and perhaps better than those achieved in the transplantation of other solid organs; patient survival, renal graft survival, and pancreatic graft survival are respectively 95%, 92%, and 85% at one Year. Results of pancreatic transplantation alone have improved and now seem equal to those of combined organ transplantation. Transplantation seems to be cost-effective in the overall care of advanced diabetes, particularly in those patients on chronic dialysis or having degenerative complications.

Pancreas transplantation improves vascular disease in patients with type 1 diabetes

OBJECTIVE

Pancreas transplantation (PTX) normalizes glucose and improves microvascular complications, but its impact on macrovascular disease is still debated.

RESEARCH DESIGN AND METHODS

Carotid intima-media thickness (IMT), shown to correlate with cardiovascular disease (CVD) risk and events, was determined prospectively by ultrasonography in successful pancreas transplant recipients to evaluate the effect of PTX on CVD risk. Carotid IMT and CVD risk factors of pancreas transplant recipients (n = 25) were compared with three groups: individuals with type 1 diabetes without significant nephropathy (n = 20), nondiabetic kidney transplant recipients (n = 16), and normal control subjects (n = 32). Mean age of pancreas transplant recipients at the time of transplantation was 42.4 +/- 1.2 years (mean +/- SE) and duration of diabetes was 25.9 +/- 1.4 years.

RESULTS

After PTX, HbA(1c) level (P < 0.0001) decreased to normal and, whereas creatinine level (P = 0.0002) decreased, it remained elevated compared with normal control subjects (P < 0.05). Blood pressure, BMI, fasting lipid levels, smoking frequency, and use of hypolipidemic agents were unchanged. Mean carotid IMT was increased in pancreas transplant candidates but decreased by 1.8 +/- 0.1 year after PTX (P = 0.0068), no longer different from that in normal control subjects or patients with type 1 diabetes.

CONCLUSIONS

Carotid IMT improves after successful PTX within 2 years of the procedure, with normalization of HbA(1c) and improved renal function, independent of changes in lipid levels, BMI, blood pressure, smoking, or use of hypolipidemic agents. This study suggests that CVD risk, future events, and mortality should improve after PTX in the absence of other significant, untreated CVD risk factors.

Impact of kidney transplantation on the progression of cardiovascular disease

Kidney transplantation, of all the treatment modalities for end-stage renal disease, affords the greatest potential for prolonged survival and improved quality of life. Great strides in immunosuppressant therapy have improved graft survival and forced clinicians to consider other health-care needs of kidney transplant recipients. Chief among these needs is the prevention and treatment of cardiovascular disease. Cardiovascular disease is the most common cause of death among patients with a working renal allograft. Because therapies for primary and secondary prevention are successful in the general population, transplant clinicians are increasingly focused on preventing or limiting the progression of cardiovascular disease. Initiation of aggressive management of conventional atherosclerotic risk factors and uremia-related risk factors, ideally during the early stages of chronic kidney disease (CKD) or after kidney transplantation, and efforts to delay the progression of kidney disease will hopefully reduce the cardiovascular burden in transplant recipients.

L-arginine-induced vasodilation of the renal vasculature is preserved in uremic type 1 diabetic patients after kidney and pancreas but not after kidney-alone transplantation

OBJECTIVE

In uremic type 1 diabetic patients, kidney and pancreas transplantation (KP) and kidney-alone transplantation (KD) provide full restoration of normal renal function; however, only KP, i.e., curing diabetes, is expected to prevent endothelial damages. Our aim was to study L-arginine-induced vasodilation of the renal vasculature in uremic type 1 diabetic patients after KP or KD using magnetic resonance (MR).

RESEARCH DESIGN AND METHODS

MR quantitative flow measurements were performed in 15 KP patients (mean age 39.0 +/- 1.7 years, 10 men and 5 women), in 11 KD patients (mean age 47.3 +/- 1.9 years, 7 men and 4 women), and in 8 nondiabetic kidney transplant patients (mean age 44.0 +/- 4.8 years, 7 men and 1 woman), who were used as control subjects, to measure renal blood flow and velocity and renal vascular resistance before and immediately after infusion of L-arginine.

RESULTS

Renal blood flow and velocity were not different at baseline in KP, KD, and control subjects. In contrast, during L-arginine administration renal blood flow increased significantly in KP subjects (basal 8.4 +/- 0.6 vs. post 9.6 +/- 0.8 ml/s, Delta 14.3 +/- 4.4%, P < 0.05) and in control subjects (basal 9.3 +/- 0.8 vs. post 9.1 +/- 0.8 ml/s, Delta 17.3 +/- 6.2%, P < 0.01), while it remained unchanged in KD subjects (basal 10.0 +/- 0.8 vs. post 11.6 +/- 0.9 ml/s, Delta -1.36 +/- 6.9%, NS). Parallel results have been achieved for renal blood velocity (KP subjects: 20.1 +/- 4.9%, P < 0.01; control subjects: 23.0 +/- 7.99%, P < 0.01; and KD subjects: -0.3 +/- 6.5%; NS). A reduction in renal vascular resistance in response to L-arginine was evident in KP and control subjects but not in KD patients.

CONCLUSIONS

L-Arginine vasodilatory response was successfully assessed with MR quantitative flow measurements. KP patients and control subjects, but not those with KD, showed a preserved L-arginine-induced vasodilation of the renal vasculature.

Pancreas transplant alone determines early improvement of cardiovascular risk factors and cardiac function in type 1 diabetic patients1

BACKGROUND

The effects of pancreas transplant alone (PTA) on cardiovascular risk factors (CRF) and cardiac function in type 1 diabetes mellitus (T1DM) patients are still unsettled.

METHODS

We studied 13 T1DM patients who received PTA with portal drainage and 11 matched control patients. Parameters of glucose and lipid metabolism and several additional classic CRF were assessed before and up to 6 months posttransplant. Cardiac morphology and function were assessed by Doppler echocardiographic examination.

RESULTS

Insulin independence was promptly achieved and then maintained after PTA. Total and low-density lipoprotein cholesterol levels were significantly lower after transplantation, whereas high-density lipoprotein cholesterol and triglyceride concentrations did not change. Both systolic and diastolic blood pressure values and fibrinogen levels improved significantly. In addition, PTA determined a significant amelioration of several morphologic and functional cardiac indices. None of the measured parameters changed in the control patients.

CONCLUSIONS

PTA with portal drainage induces an early improvement of CRF and ameliorates cardiac function in patients with T1DM.

Macrovascular events after kidney-pancreas transplantation in type 1 diabetic patients

BACKGROUND

There are few studies concerning the effect of kidney-pancreas transplantation (KPTx) on the progression of macrovascular disease in type 1 diabetic patients. The aim of our study was to retrospectively evaluate the incidence of macrovascular events after functioning KPTx.

MATERIALS AND METHODS

We studied 146 patients (96 men and 50 women) who had undergone KPTx from February 1983 to September 2001, with more than 1 year of evolution of both grafts functioning normally. The mean follow-up of the patients after KPTx was 5+/-3 years.

RESULTS

Before KPTx, 29 patients displayed 42 macrovascular events. During the follow-up after transplantation, intermittent claudication remained in 25 patients (86.2%) with 11 new macrovascular events (1 stroke, 1 angina pectoris, 1 myocardial infarction, and 8 minor amputations) in 10 patients (34%). Among the 117 patients without antecedent macrovascular events prior to KPTx, 38 (32.5%) experienced a total of 63 macrovascular events (26 intermittent claudication, 4 stroke, 8 angina pectoris, 7 myocardial infarction, 11 minor amputations, and 7 major amputations). Before transplantation, 88.4% of the patients presented with hypertension, 42.5% a history of smoking, and 14.4% previous treatment for dyslipidmia. After transplantation, we observed an important reduction in the percentage of patients with hypertension (48.6%) and smoking (25.5%), without a change in the prevalence of dyslipemia (19.9%). Hypertension after transplantation was clearly associated with the appearance or persistence of macrovascular events.

CONCLUSION

In our experience, 43% of the transplant recipients present with macrovascular events. It is important to note the elevated prevalence of cardiovascular risk factors in the patients who underwent KPTx.