Pancreas transplantation after bariatric surgery

Modern indications for referral for kidney and pancreas transplantation

PURPOSE OF REVIEW

Pancreas transplantation (PTx) is currently the only therapy that can predictably achieve sustained euglycemia independent of exogenous insulin administration in patients with insulin-dependent diabetes mellitus. This procedure involves a complex abdominal operation and lifetime dependence on immunosuppressive medications. Therefore, PTx is most frequently performed in combination with other organs, usually a kidney transplant for end stage diabetic nephropathy. Less frequently, solitary PTx may be indicated in patients with potentially life-threatening complications of diabetes mellitus. There remains confusion and misperceptions regarding indications and timing of patient referral for PTx.

RECENT FINDINGS

In this review, the referral, evaluation, and listing process for PTx is described, including a detailed discussion of candidate assessment, indications, contraindications, and outcomes.

SUMMARY

Because the progression of diabetic kidney disease may be less predictable than other forms of kidney failure, early referral for planning of renal and/or pancreas transplantation is paramount to optimize patient care and allow for possible preemptive transplantation.

Pancreas Transplantation in Minorities including Patients with a Type 2 Diabetes Phenotype

Background: Prior to year 2000, the majority of pancreas transplants (PTx) were performed as simultaneous pancreas-kidney transplants (SPKTs) in Caucasian adults with end stage renal failure secondary to type 1 diabetes mellitus (T1DM) who were middle-aged. In the new millennium, improving outcomes have led to expanded recipient selection that includes patients with a type 2 diabetes mellitus (T2DM) phenotype, which excessively affects minority populations. Methods: Using PubMed® to identify appropriate citations, we performed a literature review of PTx in minorities and in patients with a T2DM phenotype. Results: Mid-term outcomes with SPKT in patients with uremia and circulating C-peptide levels (T2DMphenotype) are comparable to those patients with T1DM although there may exist a selection bias in the former group. Excellent outcomes with SPKT suggests that the pathophysiology of T2DM is heterogeneous with elements consisting of both insulin deficiency and resistance related to beta-cell failure. As a result, increasing endogenous insulin (Cp) production following PTx may lead to freedom checking blood sugars or taking insulin, better metabolic counter-regulation, and improvements in quality of life and life expectancy compared to other available treatment options. Experience with solitary PTx for T2DM or in minorities is limited but largely mirrors the trends reported in SPKT. Conclusions: PTx is a viable treatment option in patients with pancreas endocrine failure who are selected appropriately regardless of diabetes type or recipient race. This review will summarize data that unconventional patient populations with insulin-requiring diabetes may gain value from PTx with an emphasis on contemporary experiences and appropriate selection in minorities in the new millennium.

Sleeve gastrectomy enables simultaneous pancreas and kidney transplantation in severely obese recipients

BACKGROUND

Obesity adversely affects wait-listing and precludes patients with concomitant end-stage renal disease and type 1 diabetes mellitus from getting a simultaneous pancreas and kidney transplantation (SPK).

OBJECTIVE

To analyze safety and efficacy of laparoscopic sleeve gastrectomy (LSG) before SPK in severely obese type I diabetics.

METHODS

We assessed weight curve, complications, and graft function of three patients who underwent LSG before SPK.

RESULTS

LSG was uneventful in all patients. Body mass index dropped from 38.4 (range 35.7 - 39.9) before LSG to 28.5 (26.8 - 30.9) until SPK, with a mean loss of 25.8% (22.4 - 32.3). Interval between LSG and SPK was 364.3 (173 - 587) days. Pancreas and kidney graft function was excellent, with 100% insulin-free and dialysis-free survival over a mean follow-up of 3.6 (2.9 - 4.5) years. A1C dropped from 7% (6.3 - 8.2) before LSG to 4.9% (4.7 - 5.3) and 4.8% (4.5 - 5.1) 1 and 2 years after SPK, respectively.

CONCLUSION

LSG before SPK is safe and effective to enable severely obese type I diabetics to receive a lifesaving transplant. This is the first study analyzing the role of bariatric surgery before simultaneous pancreas and kidney transplantation.

Pancreas transplantation in type 2 diabetes: expanding the criteria

PURPOSE OF REVIEW

Pancreas transplantation in type 2 diabetes mellitus (T2DM) candidates remains disproportionately lower than in type 1 diabetes mellitus (T1DM); however, outcomes in carefully selected patients mirrors that of T1DM. Despite the 2014 United Network for Organ Sharing (UNOS) eligibility criteria for simultaneous pancreas/kidney transplant (SPK) transplantation in T2DM patients, an expected increase in the number of transplants was not observed.

RECENT FINDINGS

In an updated International Pancreas and Transplant Registry (IPTR) analysis, 1514 primary deceased donor pancreas transplants were performed in T2DM recipients [1995-2015, SPK 88%, pancreas after kidney (PAK) 9%, pancreas transplant alone (PTA) 3%]. In contrast to the declining number of SPK transplants for T1DM, the number of primary SPK transplants in T2DM patients is increasing over time in the USA. Improvement over time was noted for T2DM SPK patient and graft survival, and the rate of technical failures decreased, paralleling similar overall trends for pancreas transplants in general. Long-term follow-up data of pancreas outcomes in C-peptide positive vs. negative demonstrate noninferior outcomes. BMI does not appear to impact outcomes in carefully selected T2DM candidates.

SUMMARY

The current UNOS regulations that currently limit access of T2DM to pancreas transplantation based on strict BMI criteria and C-peptide levels need to be liberated.

Protracted Hypocalcemia following 3.5 Parathyroidectomy in a Kidney Pancreas Recipient with a History of Robotic-Assisted Roux-en-Y Gastric Bypass

Background

Hypocalcemia is a frequent complication of parathyroidectomy for secondary/tertiary hyperparathyroidism. In patients with a history of prior Roux-en-Y gastric bypass (RYGBP), changes in nutritional absorption make management of hypocalcemia after parathyroidectomy difficult.

Case Report

A 41-old-year morbidly obese female with c-peptide negative diabetes mellitus and renal failure had RYGBP. Following significant weight loss she underwent simultaneous pancreas-kidney transplantation. She had excellent transplant graft function but developed tertiary hyperparathyroidism with calciphylaxis. She underwent resection of 3.5 glands leaving a small, physiologic remnant remaining in situ at the left inferior position. She was discharged on postoperative day one in good condition, asymptomatic with serum calcium of 7.6 mg/dL and intact PTH of 12 pg/mL. The patient had to be readmitted on postoperative day #14 for severe hypocalcemia of 5.0 mg/dl and ionized calcium 2.4 mg/dl. She required intravenous calcium infusion to achieve calcium levels of >6.5 mg/dl. Long-term treatment includes 5 g of elemental oral calcium TID, vitamin D, and hydrochlorothiazide. She remains in the long term on high-dose medical therapy with normal serum calcium levels and PTH levels around 100 pg/mL.

Discussion

Our patient's protracted hypocalcemia originates from a combination of 3.5 gland parathyroidectomy, altered intestinal anatomy post-RYGBP, and potentially her pancreas transplant causing additional metabolic derangement. Alternative bariatric procedures such as sleeve gastrectomy may be more suitable for patients with renal failure or organ transplants in whom adequate absorption of vitamins, minerals, and drugs such as immunosuppressants is essential.

Pancreas transplantation in unconventional recipients

PURPOSE OF REVIEW

Advances in surgical technique and immunosuppression have significantly improved outcomes after pancreas transplantation, and as a result pancreas transplants increasingly are being performed for indications other than type 1 diabetes mellitus. This review summarizes the current literature on pancreas transplantation in unconventional recipient populations.

RECENT FINDINGS

An increasing body of work suggests that pancreas transplantation can be performed with good outcomes in patients with type 2 diabetes mellitus and those 50 years of age and older. Obesity appears detrimental to patient and pancreas graft survival, and bariatric surgery prior to transplantation may be of increasing interest and relevance. There are limited data yielding mixed outcomes on pancreas transplantation in patients with HIV or hepatitis C virus. However, rapidly improving antiviral therapies are prolonging survival in patients with HIV and chronic hepatitis C virus infections and may increase the number of candidates available for pancreas transplantation in these populations in the future.

SUMMARY

Despite limited literature in these patient populations, pancreas transplantation may be a viable treatment option for endocrine pancreas failure in appropriately selected patients regardless of disease cause or age.

Robotic pancreas transplantation in a type 1 diabetic patient with morbid obesity: A case report

RATIONALE

Obesity is considered a relative contraindication to pancreas transplantation due to increased risks of wound-related complications. Robotic surgeries have never been applied for pancreas transplantation in obese recipients though robotic kidney transplantation did and already proved its value in reducing wound-related complications in obese recipients.

PATIENT CONCERNS & DIAGNOSES

We performed the first robotic pancreas after kidney transplantation for a 34-year-old Hispanic type 1 diabetic male with class III obesity (BMI = 41 kg/m).

INTERVENTIONS

The pancreas graft was procured and benched in the standard fashion. Methylene blue was used to detect any vascular leaks. The operation was completed via two 12-mm ports (camera, laparoscopic bed-side assistance), two 8-mm ports for robotic arms, and a 7-cm epigastric incision for hand port. The portal vein and arterial Y-graft of the pancreas were anastomosed to the recipient's left external iliac vein and artery, respectively. Duodenum-bladder drainage was performed with a circular stapler.

OUTCOMES

Duration of warm and cold ischemia was: 45 minutes and 7 hours, respectively. The patient was discharged uneventfully without wound-related complications. Excellent metabolic control was achieved with hemoglobin A1c lowering from 9% before transplantation to 4.4% on day 120. The patient remained in nondiabetic status in 1-year follow-up.

LESSONS

In conclusion, robotic pancreas transplantation is feasible in patients with morbid obesity.

Two-stage surgery to repair a dissecting abdominal aortic aneurysm in a severely obese patient: Open bifurcated graft replacement after laparoscopic sleeve gastrectomy

With the increasing prevalence of severe obesity worldwide, surgical treatment for severely obese patients is becoming more popular. Bariatric surgery has occasionally been performed as a precursor to major operations for serious diseases to make these difficult surgeries safer for severely obese patients. We present the case of a severely obese patient with a dissected abdominal aortic aneurysm and left iliac artery aneurysm. Initially, we performed bariatric surgery on this patient to reduce perioperative risk and then subsequently performed bifurcated graft replacement. A 54-year-old man presented at our hospital for bariatric surgery before open abdominal aortic aneurysm repair. Laparoscopic sleeve gastrectomy was performed; 15 months later, the patient's weight and BMI had decreased from 139.0 kg to 97.6 kg and from 48.7 kg/m(2) to 34.2 kg/m(2) , respectively. Bifurcated graft replacement was performed safely without postoperative complications. Bariatric surgery was also effective in controlling the patient's blood pressure during the interval between surgeries.

Impact of recipient body mass index on short-term and long-term survival of pancreatic grafts

BACKGROUND

The impact of recipient body mass index on graft and patient survival after pancreas transplantation is not well known.

METHODS

We have analyzed data from all pancreas transplant recipients reported in the Scientific Registry of Transplant Recipients between 1987 and 2011. Recipients were categorized into BMI classes, as defined by the World Health Organization. Short-term (90 days) and long-term (90 days to 5 years) patient and graft survivals were analyzed according to recipient BMI class using Kaplan-Meier estimates. Hazard ratios were estimated using Cox proportional hazard models.

RESULTS

A total of 21,075 adult recipients were included in the analysis. Mean follow-up was 5 ± 1.1 years. Subjects were overweight or obese in 39%. Increasing recipient BMI was an independent predictor of pancreatic graft loss and patient death in the short term (P<0.001), especially for obese class II patient survival (hazard ratio, 2.07; P=0.009). In the long term, obesity, but not overweight, was associated with higher risk of graft failure (P=0.01). Underweight was associated with a higher risk of long-term death (P<0.001).

CONCLUSION

These results question the safety of pancreas transplantation in obese patients and suggest that they may be directed to alternate therapies, such as behavioral modifications or bariatric surgery, before pancreas transplantation is considered.

Transplant options for patients with type 2 diabetes and chronic kidney disease

Chronic kidney disease (CKD) has become a real epidemic around the world, mainly due to ageing and diabetic nephropathy. Although diabetic nephropathy due to type 1 diabetes mellitus (T1DM) has been studied more extensively, the vast majority of the diabetic CKD patients suffer from type 2 diabetes mellitus (T2DM). Renal transplantation has been established as a first line treatment for diabetic nephropathy unless there are major contraindications and provides not only a better quality of life, but also a significant survival advantage over dialysis. However, T2DM patients are less likely to be referred for renal transplantation as they are usually older, obese and present significant comorbidities. As pre-emptive renal transplantation presents a clear survival advantage over dialysis, all T2DM patients with CKD should be referred for early evaluation by a transplant center. The transplant center should have enough time in order to examine their eligibility focusing on special issues related with diabetic nephropathy and explore the best options for each patient. Living donor kidney transplantation should always be considered as the first line treatment. Otherwise, the patient should be listed for deceased donor kidney transplantation. Recent progress in transplantation medicine has improved the “transplant menu” for T2DM patients with diabetic nephropathy and there is an ongoing discussion about the place of simultaneous pancreas kidney (SPK) transplantation in well selected patients. The initial hesitations about the different pathophysiology of T2DM have been forgotten due to the almost similar short- and long-term results with T1DM patients. However, there is still a long way and a lot of ethical and logistical issues before establishing SPK transplantation as an ordinary treatment for T2DM patients. In addition recent advances in bariatric surgery may offer new options for severely obese T2DM patients with CKD. Nevertheless, the existing data for T2DM patients with advanced CKD are rather scarce and bariatric surgery should not be considered as a cure for diabetic nephropathy, but only as a bridge for renal transplantation.

Obesity and organ transplantation: successes, failures, and opportunities

The increasing rate of societal obesity is also affecting the transplant world through obesity in candidates and donors as well as its posttransplant repercussions. Being overweight and obese has been shown to have significant effects on both short- and long-term complications as well as patient and graft survival. However, much of the comorbidity can be controlled or prevented with careful patient selection and aggressive management. A team approach to managing obesity and its comorbidities both pre- and posttransplant is essential for successful transplant outcomes. Complicating understanding the results of obesity research is the inclusion different weight categories, use of listing vs transplant weights, patient populations large enough for statistical power, and changes in transplant management, especially immunosuppression protocols, anti-infection protocols, and operative techniques. Much more research is needed regarding many elements, including safe weight loss before transplantation, prevention of weight gain after transplant, genomic influences, and the role of bariatric surgery in the transplant process.

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.