Stabilisation of diabetic retinopathy following simultaneous pancreas and kidney transplant

Intravenous injection of cyclosporin A loaded lipid nanocapsules fights inflammation and immune system activation in a mouse model of diabetic retinopathy

Inflammation and immune system activation are key pathologic events in the onset and escalation of diabetic retinopathy (DR). Both are driven by cytokines and complement originating from the retinal pigment epithelium (RPE). Despite the RPE's pivotal role, there is no therapeutic tool to specifically interfere with the RPE-related pathomechanism. A therapy that addresses RPE cells and counteracts inflammation and immune response would be of paramount value for the early treatment of DR, where currently are no specific therapies available. Here, we utilized lipoprotein-mimetic lipid nanocapsules to deliver the anti-inflammatory and immunosuppressive drug cyclosporin A (CsA) to RPE cells. Using a mouse model of DR that mirrors all pathologic aspects of human DR, we demonstrate that intravenously applied CsA-loaded lipid nanocapsules comprehensively counteract inflammation and immune system activation. One single injection suppressed the expression of pro-inflammatory cytokines, dampened macrophage infiltration, and prevented macrophage and microglia activation in eyes with DR. This work shows that CsA-loaded lipid nanocapsules can offer new avenues for the treatment of DR.

Comparing Outcomes and Cost Between Pancreas Transplant and Standard of Care in Patients With Type 1 Diabetes

OBJECTIVES

Pancreas transplant is the only treatment that establishes normal glucose levels for patients diagnosed with diabetes. We analyzed the outcome of pancreas transplant alone (PTA) versus standard of care in the United States from 2008 to 2018. We also developed an economic model to analyze the cost-effectiveness of pancreas transplant versus continuing standard of care.

METHODS

We used the Scientific Registry of Transplant Recipients database and analyzed PTA recipient survival. Using those results, we developed a Markov model that followed a cohort of 40-year-old patients with type 1 diabetes over a 10-year time horizon. The primary outcomes were (i) the survival benefit of a pancreas transplant, (ii) quality-adjusted life-years (QALYs), and (iii) total costs.

RESULTS

We found no difference in survival advantage of PTA compared with standard of care (hazard ratio, 1.09; 95% confidence interval, 0.56-2.14). However, pancreas transplant ($172,823, 6.87 QALY) was cost-saving compared with standard of care ($232,897, 6.04 QALY) for type 1 diabetes. Pancreas transplantation was cost-effective in 95% of 10,000 simulations in probabilistic sensitivity analysis, using a $100,000/QALY willingness-to-pay threshold.

CONCLUSIONS

Although there is no difference in survival for PTA compared with standard of care, PTA is a cost-saving therapy for type 1 diabetes.

Hemoperfusion and functional state of the macula after simultaneous pancreas and kidney transplantation

Simultaneous pancreas and kidney transplantation (SPK) provides effective treatment in patients with type 1 diabetes mellitus (T1DM) and end-stage renal failure (ESRF), mitigating the hyperglycemia and uremic syndrome. The study aimed at the assessment of morphofunctional status of the macula and macular hemodynamics in patients with T1DM after SPK. The study enrolled 45 patients subdivided into three groups: Group A — patients with T1DM after SPK; Group B — patients with T1DM and ESRF, maintained on programmed hemodialysis (PH), on waiting list for SPK; and Group C — individuals without ophthalmic or systemic pathologies. All patients were subject to the standard ophthalmological examination complemented by measurements of the central retinal thickness (CRT) and the average perfusion density (PD) in four vascular layers: superficial capillary plexus of the retina (SCP), deep capillary plexus of the retina (DCP), choriocapillaris, and choroid. The patients after SPK had significantly lower CRT (241 ± 33 µm in Group A, 309±10 µm in Group B; p < 0.05) and significantly higher PD of the macular region in both the retina (Group A: SCP — 19.0 ± 1.6%, DCP — 10.7 ± 1.3%; Group B: SCP — 11.7 ± 0.8%, DCP — 4.8 ± 0.8%; p < 0.05) and the choroid (Group A: choriocapillaris — 28.1 ± 1.8%, choroid — 31.3 ± 1.6%; Group B: choriocapillaris — 20.4 ± 1.6%, choroid — 21.8 ± 1.3%; p < 0.05), as well as significantly higher visual acuity (Group A: 0.7 ± 0.1; Group B: 0.5 ± 0.1; p < 0.05) and macular light threshold (Group A: 25.9 ± 1.4 dB; Group B: 22.3 ± 1.1 dB; p < 0.05) compared with the patients on PH. Thus, the normalization of carbohydrate metabolism and the mitigation of uremic syndrome in patients with T1DM and ESRF after SPK favorably affect the functional condition of the macular area, as indicated by the improvement in macular blood flow and visual functions.

EYE DISEASE IN KIDNEY TRANSPLANTATION: CLINICAL CHALLENGES IN A UNIQUE PATIENT POPULATION

Eye disease is common among kidney transplant recipients and their management is challenging. Chronic kidney disease is associated with ocular complications, both independently and in the context of various systemic disorders. In addition, chronic immunosuppression predisposes kidney transplant recipients to an array of long-term ocular issues. This may be broadly categorized into infections, malignancies, and other immunosuppression-specific side effects. The interdependence of kidney disease, transplant pharmacotherapy and ocular health therefore requires a multispecialty approach. Although the kidney transplant population has grown along with the burden of associated oculopathies, systematic guidelines targeting this patient group are lacking. This evidenced-based narrative review summarizes the pertinent issues that may present in the ophthalmic and optometric clinical settings, with emphasis on collaborative management and directions for future research.

Recent Advancements in the Medical Treatment of Diabetic Retinal Disease

Diabetic retinal disease remains one of the most common complications of diabetes mellitus (DM) and a leading cause of preventable blindness. The mainstay of management involves glycemic control, intravitreal, and laser therapy. However, intravitreal therapy commonly requires frequent hospital visits and some patients fail to achieve a significant improvement in vision. Novel and long-acting therapies targeting a range of pathways are warranted, while evidence to support optimal combinations of treatments is currently insufficient. Improved understanding of the molecular pathways involved in pathogenesis is driving the development of therapeutic agents not only targeting visible microvascular disease and metabolic derangements, but also inflammation and accelerated retinal neurodegeneration. This review summarizes the current and emerging treatments of diabetic retinal diseases and provides an insight into the future of managing this important condition.

Early worsening of diabetic retinopathy after simultaneous pancreas and kidney transplantation-Myth or reality?

Early worsening of diabetic retinopathy due to sudden glucose normalization is a feared complication of pancreas transplantation; however, its rate or severity has not been studied prospectively. We followed up 43 pancreas and kidney recipients for a composite endpoint comprising new need for laser therapy, newly diagnosed proliferation, macular edema, visual acuity worsening, and blindness over 12 months. Although 37% of patients met this primary endpoint, its severity was rather low. Mean central retinal thickness and proportion of patients with subclinical macular edema increased significantly, with spontaneous resolution in half of them. Visual acuity did not change. There was no significant difference in the absolute glycated hemoglobin (HbA1c) drop, age, and diabetes duration between the patients who met and those who did not meet the primary endpoint, but a higher proportion of patients with worsening had a recent history of laser treatment. Retinopathy remained stable in 62.8% of patients. In 26%, the visual acuity significantly improved. Although retinopathy worsening was documented in more than one-third of patients, its evolution was not related to the magnitude of metabolic change; rather, it corresponded to the expected natural course of retinopathy. Nonetheless, comprehensive ophthalmologic care should be a substantial component of the recipient management.

Pancreas Retransplant After Pancreas Graft Failure in Simultaneous Pancreas-kidney Transplants Is Associated With Better Kidney Graft Survival

Background.

Simultaneous pancreas-kidney (SPK) transplant is usually the best option for the diabetic end-stage renal disease patient. There is limited information about kidney graft outcomes in SPK recipients with isolated pancreas graft failure who do versus do not undergo pancreas retransplantation.

Methods.

Patients were divided into 2 groups based on whether they underwent pancreas retransplant (ReTx⁺) or not (ReTx⁻). Kidney graft function and survival were the primary endpoints.

Results.

One hundred and nine patients satisfied our selection criteria, 25 in ReTx⁺ and 84 in ReTx⁻. Mean interval from SPK to pancreas failure was significantly shorter in the ReTx⁺ compared with the ReTx⁻ group, 19.3 ± 36.7 versus 45.7 ± 47.0 months (P = 0.01), respectively. There was no significant difference in kidney graft follow-up post SPK between 2 groups (P = 0.48). At last follow-up, 15 of the 25 (60%) of the repeat pancreas graft had failed, with a mean graft survival among these failed pancreas graft of 2.6 ± 2.7 years, ranging from 0 to 8.1 years. Uncensored kidney graft failure was significantly lower in the ReTx⁺ group compared with the ReTx⁻ group, 44% versus 67% (P = 0.04). Death-censored kidney graft failure was also lower in the ReTx⁺ group, 24% versus 48% (P = 0.04). The difference in patient survival did not reach statistical significance. In adjusted Cox regression analysis, rejection as a cause of pancreas failure was associated with increased risk of death-censored kidney graft failure, and pancreas retransplantation was associated with decreased risk of kidney graft failure. A similar pattern was seen after 1:1 matching for the interval between SPK and pancreas graft failure.

Conclusions.

Even though ReTx⁺ patients accept the risks associated with repeat pancreas surgery, providers should consider this option in suitable otherwise healthy patients.

Understanding the mechanisms of reversal of type 2 diabetes

Clinical and pathophysiological studies have shown type 2 diabetes to be a condition mainly caused by excess, yet reversible, fat accumulation in the liver and pancreas. Within the liver, excess fat worsens hepatic responsiveness to insulin, leading to increased glucose production. Within the pancreas, the β cell seems to enter a survival mode and fails to function because of the fat-induced metabolic stress. Removal of excess fat from these organs via substantial weight loss can normalise hepatic insulin responsiveness and, in the early years post-diagnosis, is associated with β-cell recovery of acute insulin secretion in many individuals, possibly by redifferentiation. Collectively, these changes can normalise blood glucose levels. Importantly, the primary care-based Diabetes Remission Clinical Trial (DiRECT) showed that 46% of people with type 2 diabetes could achieve remission at 12 months, and 36% at 24 months, mediated by weight loss. This major change in our understanding of the underlying mechanisms of disease permits a reassessment of advice for people with type 2 diabetes.

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.

Long-term Effects of Pancreas Transplantation on Diabetic Retinopathy and Incidence and Predictive Risk Factors for Early Worsening

BACKGROUND

Limited data are available regarding the long-term effects of pancreas transplantation on the progression of diabetic retinopathy (DR) and the incidence and associated risk factors for early worsening of DR.

METHODS

Patients who underwent successful pancreas transplantation between January 2007 and October 2015 and were followed for 1 year or longer were consecutively enrolled. Variables regarding demographic, systemic, metabolic, and surgical factors were reviewed for each patient. DR progression was defined as (i) development or aggravation of macular edema requiring intravitreal anti-VEGF injections and/or (ii) progression of DR severity requiring panretinal photocoagulation (PRP) and/or pars planar vitrectomy (PPV). Early worsening was defined as progression within 1 year of posttransplant.

RESULTS

Three hundred three eyes of 153 patients were included in the analysis. At the pretransplant ocular evaluation, 221 eyes (72.9%) showed advanced DR with history of PRP and/or PPV. During a mean follow-up period of 4.2 years, 62 eyes (20.5%) experienced DR progression, and early worsening was noted in 57 eyes (18.8%). DR with recent PRP within pretransplant 1 year and pancreas transplant alone were significant risk factors for early worsening.

CONCLUSIONS

In 4 of 5 patients who received pancreas transplant, the degree of DR remained stable over time after transplantation. Meanwhile, early worsening of DR could occur in patients at risk, particularly within the first posttransplant year. We suggest that physicians should have a high index of suspicion and carefully monitor for early worsening of DR and timely manage possible ocular deterioration.

Retinal changes in solid organ and bone marrow transplantation patients

Objective

To evaluate retinal changes in patients who underwent solid organ or bone marrow transplantation.

Methods

A retrospective analysis of medical records of patients evaluated from February 2009 to December 2016. All patients included underwent funduscopy. Clinical and demographic data regarding transplantation and ophthalmological changes were collected.

Results

A total of 126 patients were analyzed; of these, 108 underwent transplantation and 18 were in the waiting list. Transplantation modalities were heart, lung, kidney, liver, pancreas, combined pancreas and kidney and bone marrow transplantation. The main pre-transplantation comorbidities were diabetes and arterial hypertension. Of the 108 transplanted patients, 82 (76%) had retinal changes. All patients who underwent pancreas or combined pancreas and kidney transplantation had diabetic retinopathy. The main retinal changes found were diabetic retinopathy, hypertensive retinopathy, retinal vascular occlusions, chorioretinal infections and central serous chorioretinopathy.

Conclusion

Retinal changes were either related to preexisting conditions, mainly diabetic retinopathy, or developed postoperatively as a complication of the surgical procedure, or as an infection related to the immunosuppressive status, or due to drug toxicity. These patients may present with complex ophthalmological changes and should be carefully evaluated prior to surgery and further followed by an ophthalmologist skilled in the management of diabetic retinopathy and posterior pole infections.

Heparin infusion in simultaneous pancreas and kidney transplantation reduces graft thrombosis and improves graft survival

INTRODUCTION

Thrombosis of the pancreas after transplantation is the most common cause of relaparotomy and resultant graft loss. There is currently no standard protocol consistently proven to prevent thrombosis following transplantation. Our objective was to determine whether our protocol of post-operative low-dose intravenous (IV) heparin infusion would prevent graft thrombosis without additional complications in our patients.

METHODS

A total of 66 simultaneous pancreas kidney (SPK) transplants were performed at our institution from 2004 to 2014. Patients were divided into 2 retrospective cohort groups. Group 1 patients received only acetylsalicylic acid (ASA) 81 mg/d started on post-operative day 1. Group 2 patients received IV heparin infusion beginning in the recovery room at a rate of 500 IU/h for the first 24 hours, reduced by 100 IU/h every day to stop on day 5, and then received ASA 81 mg/d afterward. Outcome and complication rates were compared between the two groups for 5 years post-transplant.

RESULTS

We observed a significant reduction in graft thrombosis and graft loss with (0/29) patients in the heparin group vs (7/33) 25.7% from the non-heparin (P<.01) with no differences in complication rates.

CONCLUSIONS

We present a heparin infusion protocol which may help prevent graft thrombosis and graft loss in SPK transplantation.

The Role of Systemic Risk Factors in Diabetic Retinopathy

Diabetic retinopathy is an increasingly common medical issue in the United States. The risk of developing the disease or having the disease progress is caused by many systemic health factors. This article examines the existing literature on the links between glycemic control, arterial hypertension, high cholesterol and hyperlipidemia, obesity, inflammatory markers, sleep-disordered breathing, and exercise with risk of diabetic retinopathy development and prevention. The literature shows benefit for good glycemic and blood pressure control. The effects of cholesterol, and lipid control, inflammatory markers, sleep-disordered breathing, obesity, and exercise are less well established.

Pancreas Transplantation in the Modern Era

The field of pancreas transplantation has evolved from an experimental procedure in the 1980s to become a routine transplant in the modern era. With short- and long-term outcomes continuing to improve and the significant mortality, quality-of-life, and end-organ disease benefits, pancreas transplantation should be offered to more patients. In this article, we review current indications, patient selection, surgical considerations, complications, and outcomes in the modern era of pancreas transplantation.

Glycemic Control in Simultaneous Islet-Kidney Versus Pancreas-Kidney Transplantation in Type 1 Diabetes: A Prospective 13-Year Follow-up

OBJECTIVE

In patients with type 1 diabetes and end-stage renal disease, combined transplantation of a kidney together with a pancreas or isolated pancreatic islets are options to improve glycemic control. The aim of this study was to compare their long-term outcome with regard to metabolic control and surgical complication rate, as well as function of the transplanted kidney.

RESEARCH DESIGN AND METHODS

We conducted a prospective cohort study in consecutive patients receiving either a pancreas or islet transplant simultaneously with or after kidney transplantation (simultaneous pancreas-kidney [SPK]/pancreas-after-kidney [PAK] or simultaneous islet-kidney [SIK]/islet-after-kidney [IAK] transplantation).

RESULTS

Ninety-four patients who had undergone SPK/PAK transplantation were compared with 38 patients who had undergone SIK/IAK transplantation over a period of up to 13 years. HbA1c levels declined from 7.8 ± 1.3% (62 ± 14 mmol/mol) to 5.9 ± 1.1% (41 ± 12 mmol/mol), and from 8.0 ± 1.3% (64 ± 14 mmol/mol) to 6.5 ± 1.1% (48 ± 12 mmol/mol), respectively, in the SPK/PAK and SIK/IAK groups (P < 0.001 for both) and remained stable during follow-up, despite a reduction in the rate of severe hypoglycemia by >90%. The 5-year insulin independence rate was higher in the SPK/PAK group (73.6 vs. 9.3% in the SIK/IAK group), as was the rate of relaparotomy after transplantation (41.5 vs. 10.5% in the SIK/IAK group). There was no difference in the rate of kidney function decline.

CONCLUSIONS

During a long-term follow-up, SPK/PAK transplantation as well as SIK/IAK transplantation resulted in a sustained improvement of glycemic control with a slightly higher glycated hemoglobin level in the SIK/IAK group. While insulin independence is more common in whole-organ pancreas recipients, islet transplantation can be conducted with a much lower surgical complication rate and no difference in kidney function decline.

The effects of renal transplantation on diabetic retinopathy: clinical course and visual outcomes

PURPOSE

To elucidate the clinical course of diabetic retinopathy (DR) after renal transplantation (RT) in a hospital based cohort.

DESIGN

Retrospective study.

MATERIALS AND METHODS

A total of 56 eyes of 28 patients, who had DR and end stage renal disease (ESRD) due to diabetes and had undergone RT, were included in this study. Diagnosis and management of DR was carried out according to early treatment of diabetic retinopathy study (ETDRS) guidelines. DR outcome was defined as worsening if there was >2 step increase in the grade of DR or need for intervention such as laser (macular or pan retinal) or vitreoretinal surgery, improvement for <2 step change while stabilization was defined if DR remained within these two limits.

RESULTS

The mean age of the patients were 48.9 years. The mean duration of diabetes in the study group was 12.7 years. The patients were followed-up for a mean period of 52.2 ± 43.6 months. The pre-transplant mean Best corrected visual acuity (BCVA) was 0.4876 log MAR units and post-transplant mean BCVA was 0.4858 (P = 0.05). However, there was a significant visual improvement in first 20 months of renal transplant (P = 0.03). Worsening of DR was noted in 16 (32%) eyes whereas improvement was seen in 4 (8%). However, majority of eyes 30 (60%) had stable retinopathy at the final follow-up.

CONCLUSIONS

RT stabilized the retinopathy status in the majority of patients although in a minor subset the disease course was unpredictable.

Long-term outcomes after organ transplantation in diabetic end-stage renal disease

Patients with type 1 diabetic end-stage renal disease (ESRD) may be offered single kidney transplantation from a live donor (LDK) or a deceased donor (DDK) to replace the lost kidney function. In the latter setting the patient may also receive a simultaneous pancreas together with a kidney from the same donor (SPK). Also in some cases a pancreas after kidney may be offered to those who have previously received a kidney alone (PAK). The obvious benefit of a successful SPK transplantation is that the patients not only recover from uremia but also obtain normal blood glucose control without use of insulin or other hypoglycemic agents. Accordingly, this combined procedure has become an established treatment for type 1 diabetic patients with ESRD. Adequate long-term blood glucose control may theoretically lead to reduced progression or even reversal of microvascular complications. Another potential beneficial effect may be improvement of patient and kidney graft survival. Development of diabetic complications usually takes a decade to develop and accordingly any potential benefits of a pancreas transplant will not easily be disclosed during the first decade after transplantation. The purpose of the review is to assess the present literature of outcomes after kidney transplantation in patients with diabetic ESRD, with our without a concomitant pancreas transplantation. The points of interest given in this review are microvascular complications, graft outcomes, cardiovascular outcomes and mortality.

Simultaneous pancreas-kidney transplantation: The role in the treatment of type 1 diabetes and end-stage renal disease

Type 1 diabetes mellitus (DM) is one of the most common and debilitating diseases to affect the world. Many patients are afflicted by microvascular and macrovascular complications, and succumb to end-stage renal disease (ESRD). Although dialysis and insulin therapy provides better glycemic control, it nonetheless significantly decreases a patient's quality of life. Moreover, they cannot reverse ESRD or alleviate complications. Simultaneous pancreas-kidney (SPK) transplantation has revolutionized the way we manage type 1 DM; it provides a physiological means of achieving normoglycemia while rendering patients free of dialysis. Understanding this procedure is important because it is becoming a more common management strategy for patients with type 1 DM. In this review, we will begin with a brief summary of type 1 DM, followed by a comprehensive description of SPK procedure, including the history and technique. We will then present the outcomes of transplantation.

Type 2 diabetes: is pancreas transplantation an option?

Transplantation of the whole vascularized pancreas can provide insulin secretion in patients with insulin-dependent, type 1 diabetes mellitus (T1D). It restores euglycemia in most patients, with the potential to impact the chronic diabetic complications and quality of life. Pancreas transplantation (PT) is presently controversial for type 2 diabetes mellitus (T2D). For those patients with severe glycemic dysregulation, T2D can be associated with the same life-threatening sequelae as T1D such as severe hypoglycemia and kidney failure that could be corrected by pancreas (and kidney) transplantation. Thus, clinical indications and patient selection criteria are very important. This chapter will review the current status of PT for T2D and discuss the options and evolution of transplant perspectives.

Microvascular damage in type 1 diabetic patients is reversed in the first year after simultaneous pancreas-kidney transplantation

Simultaneous pancreas-kidney transplantation (SPK) is an advanced treatment option for type 1 diabetes mellitus (DM) patients with microvascular disease including nephropathy. Sidestreamdarkfield (SDF) imaging has emerged as a noninvasive tool to visualize the human microcirculation. This study assessed the effect of SPK in diabetic nephropathy (DN) patients on microvascular alterations using SDF and correlated this with markers for endothelial dysfunction. Microvascular morphology was visualized using SDF of the oral mucosa in DN (n = 26) and SPK patients (n = 38), healthy controls (n = 20), DM1 patients (n = 15, DM ≥ 40 mL/min) and DN patients with a kidney transplant (KTx, n = 15). Furthermore, 21 DN patients were studied longitudinally up to 12 months after SPK. Circulating levels of angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2) and soluble thrombomodulin (sTM) were measured using ELISA. Capillary tortuosity in the DN (1.83 ± 0.42) and DM ≥ 40 mL/min (1.55 ± 0.1) group was increased and showed reversal after SPK (1.31 ± 0.3, p < 0.001), but not after KTx (1.64 ± 0.1). sTM levels were increased in DN patients and reduced in SPK and KTx recipients (p < 0.05), while the Ang-2/Ang-1 ratio was normalized after SPK and not after KTx alone (from 0.16 ± 0.04 to 0.08 ± 0.02, p < 0.05). Interestingly, in the longitudinal study, reversal of capillary tortuosity and decrease in Ang-2/Ang-1 ratio and sTM was observed within 12 months after SPK. SPK is effective in reversing the systemic microvascular structural abnormalities in DN patients in the first year after transplantation.

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.

Whole-organ pancreas transplantation at Baylor Regional Transplant Institute: a chance to cure diabetes

The success of pancreas transplantation has improved over the past several decades with advancements in surgical technique, immunosuppressive medicines, and immunologic testing. We retrospectively reviewed our experience with pancreas transplantation from 1995 to 2008. At the Baylor Regional Transplant Program, 151 pancreas transplants were performed in 147 patients: 135 were simultaneous pancreas-kidney transplants, 10 were pancreas transplants after kidney transplants, and 6 were pancreas transplants alone. Follow-up information was available for 138 patients. The 1-year acute cellular rejection rate was 31.6%; the 30-day surgical reexploration rate was 10%; and the technical failure rate was 5.3%. Five-year pancreas graft survival rates were 67% for simultaneous pancreas and kidney transplants and 50% for pancreas transplants after kidney transplants. These outcomes exceed expected results as calculated by the Scientific Registry of Transplant Recipients. In addition, the median time to transplant was 3.8 months, compared with a US median of 14.1 months. Pancreas transplantation is currently the closest thing to a cure for diabetes and should be given as an option for diabetic patients with or without end-stage renal disease.

Reduced progression of diabetic microvascular complications with islet cell transplantation compared with intensive medical therapy

BACKGROUND

The effect of islet cell transplantation (ICT) on the progression of diabetic microvascular complications is not well understood.

METHODS

We have conducted a prospective, crossover, cohort study comparing ICT with intensive medical therapy on the progression of diabetic nephropathy, retinopathy, and neuropathy.

RESULTS

The rate of decline in glomerular filtration rate is slower after ICT than on medical therapy. There was significantly more progression of retinopathy in medically treated patients than post-ICT. There was a nonsignificant trend for improved nerve conduction velocity post-ICT.

CONCLUSIONS

ICT is associated with less progression of microvascular complications than intensive medical therapy. Multicenter, randomized trials are needed to further study the role of ICT in slowing the progression of diabetic complications.

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.

The role of kidney-pancreas transplantation in diabetic kidney disease

For patients with type 1 diabetes, innovations in insulin formulations and delivery have improved the ability to achieve excellent blood glucose control. However, it is uncommon to achieve euglycemia, particularly while avoiding complications arising from hypoglycemia. Pancreas transplantation remains the only broadly applied treatment strategy that can result in normalization of blood glucose, but this must be weighed against the risks of a surgical procedure and subsequent immunosuppression. To improve this risk/benefit ratio, pancreas transplantation is typically performed in patients with kidney failure who are to undergo kidney transplantation and immunosuppression (simultaneous pancreas-kidney transplant) or who have undergone kidney transplant and are obligated to the use of immunosuppressive medications (pancreas after kidney transplant). The purpose of this review is to clarify the benefit of an added pancreas transplant in these clinical settings and formulate an approach to the patient with type 1 diabetes as they approach kidney failure.

Quality of life in simultaneous pancreas-kidney transplant recipients

BACKGROUND

Simultaneous pancreas-kidney transplantation (SPK Tx) allows dialysis and insulin therapy to be discontinued and improves the complications of diabetes mellitus type 1 (DM1). This study measure quality of life (QoL) in SPK transplant recipients and determine if there are differences in QoL between these patients and those with DM1 in renal replacement therapy (RRT).

METHODS

Short Form Health Survey 36-Item (SF-36) was administered to 69 SPK transplant recipients and 34 patients with DM1 under RRT. A descriptive analysis, multiple linear regression, ANOVA, and ordinal regression (PLUM) models were constructed.

RESULTS

QoL was higher in SPK transplant recipients than in patients receiving RRT. The best results were in the recently transplanted patients. Respect to Spanish population the men with SPK transplants scored higher on vitality and lower on general health, role limitations-physical and role limitations-emotional. Women with SPK transplants scored lower on general health. Among patients under RRT, men scored lower on the general health, physical functioning, vitality, and bodily pain while women scored lower on all dimensions. In both groups, greater age was associated with better mental health.

CONCLUSION

Positive predictive factors of QoL are SPK Tx and age while negative predictive factors are female sex and RRT.

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.

[C-peptide residual secretion makes difference on type 1 diabetes management?]

Type 1 diabetes is a chronic disease characterized by progressive destruction of the pancreatic beta cells, what leads to insulin deficiency and hyperglycemia. However, a significant secretory function may persist for long periods in a few patients, what is clinically evident through the detection of serum C peptide. This phenomenon might reduce the risk of chronic complications, severe hypoglycemias and allow easier metabolic control. It is possible that these advantages are caused, at least partially, by C peptide itself, acting directly in its target tissues.

A multi-year analysis of islet transplantation compared with intensive medical therapy on progression of complications in type 1 diabetes

BACKGROUND

We hypothesized that transplantation of islets into type 1 diabetics could improve outcomes of glucose metabolism, renal function, retinopathy, and neuropathy compared with intensive medical therapy.

METHODS

We conducted a prospective, crossover, cohort study of intensive medical therapy (group 1) versus islet cell transplantation (group 2) in 42 patients. All were enrolled in group 1 then 31 crossed over with group 2 when islet donation became available. Transplantation was performed by portal venous embolization of more than 12,000 islet equivalents/kg body weight under cover of immunosuppression with antithymocyte globulin, tacrolimus, and mycophenolate. Outcome measures were HbA1c, change in glomerular filtration rate (GFR), progression of retinopathy, and change in nerve conduction velocity. This report details interim analysis of outcomes after 34+/-18 months (group 1) and 38+/-18 months (group 2).

RESULTS

HbA1c (%) in group 1 was 7.5+/-0.9 versus 6.6+/-0.7 in group 2 (P<0.01). GFR (mL/min/month) declined in both groups (group 1 -0.45+/-0.7 vs. group 2 -0.12+/-0.7, P=0.1). Slope of the GFR decline in group 1 was significantly more than 0. Retinopathy progressed in 10 of 82 eyes in group 1 versus 0 of 51 in group 2 (P<0.01). Nerve conduction velocity (m/sec) remained stable in group 1 (47.8+/-5 to 47.1+/-5 m/sec) and group 2 (47.2+/-4.5 to 47.7+/-3.5).

CONCLUSION

Islet transplantation yields improved HbA1c and less progression of retinopathy compared with intensive medical therapy during 3 years follow-up.

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.

Diabetic retinopathy: an update

Diabetes mellitus is a major cause of avoidable blindness in both the developing and the developed countries. Significant technological advances have taken place to improve the diagnostic accuracy of diabetic retinopathy. In the last three decades, the treatment strategies have been revised to include, besides laser photocoagulation, early surgical interventions and pharmacotherapies.

Transplantation for the treatment of type 1 diabetes

Transplantation of pancreatic tissue, as either the intact whole pancreas or isolated pancreatic islets has become a clinical option to be considered in the treatment of patients with type 1 insulin-dependant diabetes mellitus. A successful whole pancreas or islet transplant offers the advantages of attaining normal or near normal blood glucose control and normal hemoglobin A1c levels without the risks of severe hypoglycemia associate with intensive insulin therapy. Both forms of transplants are also effective at eliminating the occurrence of significant hypoglycemic events (even with only partial islet function evident). Whereas whole pancreas transplantation has also been shown to be very effective at maintaining a euglycemic state over a sustained period of time, thus providing an opportunity for a recipient to benefit from improvement of their blood glucose control, it is associated with a significant risk of surgical and post-operative complications. Islet transplantation is attractive as a less invasive alternative to whole pancreas transplant and offers the future promise of immunosuppression-free transplantation through pre-transplant culture. Islet transplantation however, may not always achieve the sustained level of tight glucose control necessary for reducing the risk of secondary diabetic complications and exposes the patient to the adverse effects of immunosuppression. Although recent advances have led to an increased rate of obtaining insulin-independence following islet transplantation, further developments are needed to improve the long-term viability and function of the graft to maintain improved glucose control over time.

Transplantation for the treatment of type 1 diabetes

Transplantation of pancreatic tissue, as either the intact whole pancreas or isolated pancreatic islets has become a clinical option to be considered in the treatment of patients with type 1 insulin-dependant diabetes mellitus. A successful whole pancreas or islet transplant offers the advantages of attaining normal or near normal blood glucose control and normal hemoglobin A1c levels without the risks of severe hypoglycemia associate with intensive insulin therapy. Both forms of transplants are also effective at eliminating the occurrence of significant hypoglycemic events (even with only partial islet function evident). Whereas whole pancreas transplantation has also been shown to be very effective at maintaining a euglycemic state over a sustained period of time, thus providing an opportunity for a recipient to benefit from improvement of their blood glucose control, it is associated with a significant risk of surgical and post-operative complications. Islet transplantation is attractive as a less invasive alternative to whole pancreas transplant and offers the future promise of immunosuppression-free transplantation through pre-transplant culture. Islet transplantation however, may not always achieve the sustained level of tight glucose control necessary for reducing the risk of secondary diabetic complications and exposes the patient to the adverse effects of immunosuppression. Although recent advances have led to an increased rate of obtaining insulin-independence following islet transplantation, further developments are needed to improve the long-term viability and function of the graft to maintain improved glucose control over time.

Pancreas-kidney and pancreas transplantation for the treatment of diabetes mellitus

Kidney transplantation is the treatment of choice for end-stage diabetic nephropathy, but the ultimate treatment today for type 1 diabetes mellitus is the whole vascularized pancreas transplant. Although its use is increasing, pancreas transplantation remains an uncommonly used therapeutic option that normalizes glucose levels and results in stabilization or improvement in secondary complications far better than any other strategy available for treatment of type 1 diabetes. These documented benefits of a simultaneous kidney and pancreas transplant are the basis for its acceptance as an appropriate therapy for patients who have type 1 diabetes mellitus and end-stage renal disease.

Pancreas transplant alone has beneficial effects on retinopathy in type 1 diabetic patients

AIMS/HYPOTHESIS

The effects of successful pancreas transplant alone (PTA) on chronic complications of diabetes, in particular diabetic retinopathy, remain disputed. We prospectively studied the course of diabetic retinopathy in PTA recipients and in non-transplanted (non-PTA) type 1 diabetic patients.

METHODS

The PTA and non-PTA groups consisted respectively of 33 (follow-up: 30 +/- 11 months) and 35 patients (follow-up: 28 +/- 10 months). Best corrected visual acuity, slit lamp examination, intraocular pressure measurement, ophthalmoscopy, retinal photographs, and in selected cases angiography were performed. Diabetic retinopathy and its improvement/deterioration were assessed according to criteria proposed by the Eurodiab Study.

RESULTS

At baseline, 9% of PTA and 6% of non-PTA patients had no diabetic retinopathy, 24 and 29% had non-proliferative diabetic retinopathy (NPDR), whereas 67 and 66% had laser-treated and/or proliferative diabetic retinopathy (LT/PDR), respectively. No new case of diabetic retinopathy occurred in either group during follow-up. In the NPDR PTA group, 50% of patients improved by one grading, and 50% showed no change. In the LT/PDR PTA, stabilisation was observed in 86% of cases, whereas worsening of retinopathy occurred in 14% of patients. In the NPDR non-PTA group, diabetic retinopathy improved in 20% of patients, remained unchanged in 10%, and worsened in the remaining 70%. In the LT/PDR non-PTA group, retinopathy did not change in 43% and deteriorated in 57% of patients. Overall, the percentage of patients with improved or stabilised diabetic retinopathy was significantly higher in the PTA group. No differences were found between the two groups with regard to cataract lesions and intraocular pressure values.

CONCLUSIONS/INTERPRETATION

Despite a relatively short follow-up, our study shows that successful PTA can positively affect the course of diabetic retinopathy.

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.

Diabetic retinopathy before and after renal transplantation: a longitudinal study

Retinal evaluation was performed in 20 consecutive type 2 diabetics before and after renal transplantation. This included 19 men and 1 woman of mean age 52 years (range 30 to 60 years). Before renal transplantation, 95% of these patients showed diabetic retinopathy (50% nonproliferative and 45% proliferative diabetic retinopathy). There was no change in retinopathy at 3 months after renal transplantation. At 1 year, two patients (10%) showed deterioration in their diabetic retinopathy, while the remaining 90% did not show any change. Also 25% of renal allograft recipients developed posterior capsular cataracts.