Diabetes and other endocrine-metabolic abnormalities in the long-term follow-up of pancreas transplantation

Increase in lumbar spine but not distal radius bone mineral density in adults after pancreas kidney transplantation

Osteoporosis occurs in every third individual after simultaneous pancreas kidney transplantation (SPKT). Currently used bone measures insufficiently predict their fracture risk. Lumbar spine Trabecular bone score (TBS) and distal radius areal and volumetric bone mineral density (BMD) were monitored for the first time in patients with type 1 diabetes and chronic renal failure after SPKT with steroid-sparing protocol. In 33 subjects (mean age 43.4 ± 9.8 years), dual-energy X-ray absorptiometry and peripheral quantitative computed tomography were performed just after SPKT (baseline) and one and three years later. While TBS Z-scores increased (-1.1 ± 1.2 and -0.3 ± 1.0; p˂0.001, at baseline and year three, respectively), trabecular volumetric BMD Z-scores at distal radius metaphysis did not change during the study (-1.3 ± 1.3 and -1.3 ± 1.0; p = 0.38). Similarly, areal BMD Z-scores increased at lumbar spine, total hip and femoral neck (all p < 0.01), but not at the distal radius. SPKT induced bone measures' improvement at lumbar spine and hip but not at distal radius. Before suggesting changes in current clinical care, predictive value of individual bone measures or its combination for fracture risk assessment remains to be elucidated.

Impact of early corticosteroid withdrawal on simultaneous pancreas-kidney transplant long-term outcomes: Single center experience and comparison to the International Pancreas Transplant Registry

BACKGROUND

There remains a paucity of modern data comparing early steroid withdrawal (ESW) versus chronic corticosteroid (CCS) immunosuppression in simultaneous pancreas kidney (SPK) transplant recipients with long-term follow-up. Therefore, the purpose of this study is to assess the effectiveness and tolerability of ESW compared to CCS post-SPK.

METHODS

This was a retrospective single-center matched comparison with the International Pancreas Transplant Registry (IPTR). Patients from University of Illinois Hospital (UIH) represented the ESW group and were compared to those matched CCS patients from the IPTR. Included patients were adult recipients of a primary SPK transplant between 2003 and 2018 within the US receiving rabbit anti-thymocyte globulin induction. Patients were excluded if they had early technical failures, missing IPTR data, graft thrombosis, re-transplant, or positive crossmatch SPK.

RESULTS

A total of 156 patients were matched and included in the analysis. Patients were predominantly African American (46.15%) males (64.1%) with Type 1 diabetes etiology (92.31%). Overall pancreas allograft survival (hazard ratio [HR] = .89, 95% confidence interval [CI] .34-2.30, p = .81) and kidney allograft survival (HR = .80, 95%CI .32-2.03, p = .64) were similar between the two groups. Immunologic pancreas allograft loss was statistically similar at 1-year (ESW 1.3% vs. CCS 0%, p = .16), 5-year (ESW 1.3% vs. CCS 7.7%, p = .16), and 10-year (ESW 11.0% vs. CCS 7.7%, p = .99). The 1-year (ESW 2.6% vs. CCS 0%, p > .05), 5-year (ESW 8.3% vs. CCS 7.0%, p > .05), and 10-year (ESW 22.7% vs. CCS 9.9%, p = .2575) immunologic kidney allograft loss were also statistically similar. There was no difference in 10-year overall patient survival (ESW 76.2% vs. CCS 65.6%, p = .63).

CONCLUSIONS

No differences were found between allograft or patient survival post-SPK when comparing an ESW or CCS protocol. Future assessment is needed to determine differences in metabolic outcomes.

Simultaneous pancreas-kidney transplantation for end-stage renal failure in type 1 diabetes mellitus: Current perspectives

Type 1 diabetes mellitus (T1DM) is one of the important causes of chronic kidney disease (CKD) and end-stage renal failure (ESRF). Even with the best available treatment options, management of T1DM poses significant challenges for cli nicians across the world, especially when associated with CKD and ESRF. Substantial increases in morbidity and mortality along with marked rise in treatment costs and marked reduction of quality of life are the usual consequences of onset of CKD and progression to ESRF in patients with T1DM. Simultaneous pancreas-kidney transplant (SPK) is an attractive and promising treatment option for patients with advanced CKD/ESRF and T1DM for potential cure of these diseases and possibly several complications. However, limited availability of the organs for transplantation, the need for long-term immunosuppression to prevent rejection, peri- and post-operative complications of SPK, lack of resources and the expertise for the procedure in many centers, and the cost implications related to the surgery and postoperative care of these patients are major issues faced by clinicians across the globe. This clinical update review compiles the latest evidence and current recommendations of SPK for patients with T1DM and advanced CKD/ESRF to enable clinicians to care for these diseases.

Biomedical importance of the ubiquitin-proteasome system in diabetes and metabolic transdifferentiation of pancreatic duct epithelial cells into β-cells

The ubiquitin-proteasome system (UPS) is a major pathway for cellular protein degradation. The molecular function of the UPS is the removal of damaged proteins, and this function is applied in many biological processes, including inflammation, proliferation, and apoptosis. Accumulating evidence also suggests that the UPS also has a key role in pancreatic β-cell transdifferentiation in diabetes and can be targeted for treatment of diabetic diseases. In this review, we summarized the mechanistic roles of the UPS in the biochemical activities of pancreatic β-cells, including the role of the UPS in insulin synthesis and secretion, as well as β-cell degradation. Also, we discuss how the UPS mediates the transdifferentiation of pancreatic duct epithelial cells into β-cells as the experimental basis for the development of new strategies for the treatment of diabetes in regenerative medicine.

Bone mineral density progression following long-term simultaneous pancreas-kidney transplantation in type-1 diabetes

INTRODUCTION

Simultaneous pancreas-kidney transplantation (SPKT) has demonstrated favorable impact on the progression of chronic complications in type-1 diabetes (T1D) and terminal chronic kidney disease (CKD). However, some CKD mineral and bone disorders (CKD-MBD) may persist, even after transplantation. There are only a few studies addressing the long-term progression of bone mineral density (BMD) in these patients. Our aim was to assess baseline BMD and long-term progression and consequences in patients with T1D undergoing SPKT.

METHODS

A retrospective cohort included patients undergoing SPKT in our tertiary center between 2000 and 2017. BMD progression was assessed on dual X-ray absorptiometry (DXA). Only patients with baseline data and a minimum follow-up of 2 years were included.

RESULTS

Seventy-three patients were included, 53.4% male, with a median age at SPKT of 35 years (interquartile range [IQR] 31; 39). At transplantation, the median T-scores for the lumbar spine (LS) and femoral neck (FN) were -1.6 (IQR -2.6; -1.1) and --2.1 (IQR -2.7; -1.6), respectively. Seventy-five percent of patients presented low BMD (osteopenia or osteoporosis) in the LS and 90% in the FN, with 33% osteoporosis in the LS and 36% in the FN. On multivariate analysis, male gender (odds ratio [OR] 10.82, 95% confidence interval (CI) 2.88-40.70) and low body-mass index (BMI) (OR 0.73, 95% CI 0.55-0.97) were significantly associated with lumbar but not femoral osteoporosis. At long-term follow-up, BMD significantly improved in the LS (ΔT-score +0.41, P<0.001) and FN (ΔT-score +0.29, P=0.01), at a median 4 years after SPKT. Twelve (16.4%) and 9 (12.3%) patients showed persistent FN and LS osteoporosis, respectively. Multivariate linear regression showed that high BMI was predictive of improvement in BMD.

CONCLUSIONS

This study demonstrated severe skeletal fragility in T1D patients with terminal CKD undergoing SPKT, more than a quarter of whom showed osteoporosis. The significant improvement in BMD may result from metabolic correction by SPKT and from physiological skeleton mineralization, which continues in this age group. BMD progression was positively associated with BMI, due to improved nutritional balance after transplantation.

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.