Phase 3 Trial of Transplantation of Human Islets in Type 1 Diabetes Complicated by Severe Hypoglycemia

OBJECTIVE

Impaired awareness of hypoglycemia (IAH) and severe hypoglycemic events (SHEs) cause substantial morbidity and mortality in patients with type 1 diabetes (T1D). Current therapies are effective in preventing SHEs in 50-80% of patients with IAH and SHEs, leaving a substantial number of patients at risk. We evaluated the effectiveness and safety of a standardized human pancreatic islet product in subjects in whom IAH and SHEs persisted despite medical treatment.

RESEARCH DESIGN AND METHODS

This multicenter, single-arm, phase 3 study of the investigational product purified human pancreatic islets (PHPI) was conducted at eight centers in North America. Forty-eight adults with T1D for >5 years, absent stimulated C-peptide, and documented IAH and SHEs despite expert care were enrolled. Each received immunosuppression and one or more transplants of PHPI, manufactured on-site under good manufacturing practice conditions using a common batch record and standardized lot release criteria and test methods. The primary end point was the achievement of HbA1c <7.0% (53 mmol/mol) at day 365 and freedom from SHEs from day 28 to day 365 after the first transplant.

RESULTS

The primary end point was successfully met by 87.5% of subjects at 1 year and by 71% at 2 years. The median HbA1c level was 5.6% (38 mmol/mol) at both 1 and 2 years. Hypoglycemia awareness was restored, with highly significant improvements in Clarke and HYPO scores (P > 0.0001). No study-related deaths or disabilities occurred. Five of the enrollees (10.4%) experienced bleeds requiring transfusions (corresponding to 5 of 75 procedures), and two enrollees (4.1%) had infections attributed to immunosuppression. Glomerular filtration rate decreased significantly on immunosuppression, and donor-specific antibodies developed in two patients.

CONCLUSIONS

Transplanted PHPI provided glycemic control, restoration of hypoglycemia awareness, and protection from SHEs in subjects with intractable IAH and SHEs. Safety events occurred related to the infusion procedure and immunosuppression, including bleeding and decreased renal function. Islet transplantation should be considered for patients with T1D and IAH in whom other, less invasive current treatments have been ineffective in preventing SHEs.

Effect of Immigration Status on Outcomes in Pediatric Kidney Transplant Recipients

Kidney transplantation is the optimal treatment for children with end-stage renal disease. For children with undocumented immigration status, access to kidney transplantation is limited, and data on transplant outcomes in this population are scarce. The goal of the present retrospective single-center study was to compare outcomes after kidney transplantation in undocumented children with those of US citizen children. Undocumented residency status was identified in 48 (17%) of 289 children who received a kidney transplant between 1998 and 2010. In undocumented recipients, graft survival at 1 and 5 years posttransplantation was similar, and mean estimated glomerular filtration rate at 1 year was higher than that in recipients who were citizens. The risk of allograft failure was lower in undocumented recipients relative to that in citizens at 5 years posttransplantation, after adjustment for patient age, donor age, donor type, and HLA mismatch (p < 0.04). In contrast, nearly one in five undocumented recipients who reached 21 years of age lost their graft, primarily because they were unable to pay for immunosuppressive medications once their state-funded insurance had ended. These findings support the ongoing need for immigration policies for the undocumented that facilitate access to work-permits and employment-related insurance for this disadvantaged group.

A Multicenter Study: North American Islet Donor Score in Donor Pancreas Selection for Human Islet Isolation for Transplantation

Selection of an optimal donor pancreas is the first key task for successful islet isolation. We conducted a retrospective multicenter study in 11 centers in North America to develop an islet donor scoring system using donor variables. The data set consisting of 1,056 deceased donors was used for development of a scoring system to predict islet isolation success (defined as postpurification islet yield >400,000 islet equivalents). With the aid of univariate logistic regression analyses, we developed the North American Islet Donor Score (NAIDS) ranging from 0 to 100 points. The c index in the development cohort was 0.73 (95% confidence interval 0.70-0.76). The success rate increased proportionally as the NAIDS increased, from 6.8% success in the NAIDS < 50 points to 53.7% success in the NAIDS ≥ 80 points. We further validated the NAIDS using a separate set of data consisting of 179 islet isolations. A comparable outcome of the NAIDS was observed in the validation cohort. The NAIDS may be a useful tool for donor pancreas selection in clinical practice. Apart from its utility in clinical decision making, the NAIDS may also be used in a research setting as a standardized measurement of pancreas quality.

Expanded indications for bariatric surgery: should patients on chronic steroids be offered bariatric procedures?

BACKGROUND

Patients who take chronic corticosteroids are increasingly referred for bariatric surgery. Little is known about their clinical outcomes.

OBJECTIVE

Determine whether chronic steroid use is associated with increased morbidity and mortality after stapled bariatric procedures.

SETTING

American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database.

METHODS

All patients who underwent laparoscopic sleeve gastrectomy or laparoscopic Roux-en-Y gastric bypass and were reported to the ACS-NSQIP from 2011 to 2013 were reviewed. Patients were grouped based on type of surgery and history of chronic steroid use. Primary outcome measures were mortality and serious morbidity in the first 30 days. Regression analyses were used to determine predictors of outcome.

RESULTS

Of 23,798 patients who underwent laparoscopic sleeve gastrectomy and 38,184 who underwent Roux-en-Y gastric bypass, 385 (1.6%) and 430 (1.1%), respectively, were on chronic steroids. Patients on chronic steroids had a 3.4 times increased likelihood of dying within 30 days (95% confidence interval 1.4-8.1, P = .007), and 2-fold increased odds of serious complications (95% confidence interval 1.2-2.3, P = .008), regardless of surgery type. In multivariate regression, steroid usage remained an independent predictor of mortality and serious complications.

CONCLUSION

In a large, nationally representative patient database, steroid use independently predicted mortality and serious postoperative complications after stapled bariatric procedures. Surgeons should be cautious about offering stapled bariatric procedures to patients on chronic steroids.

Intestinal Calcium Absorption Decreases Dramatically After Gastric Bypass Surgery Despite Optimization of Vitamin D Status

Roux-en-Y gastric bypass (RYGB) surgery has negative effects on bone, mediated in part by effects on nutrient absorption. Not only can RYGB result in vitamin D malabsorption, but the bypassed duodenum and proximal jejunum are also the predominant sites of active, transcellular, 1,25(OH)2 D-mediated calcium (Ca) uptake. However, Ca absorption occurs throughout the intestine, and those who undergo RYGB might maintain sufficient Ca absorption, particularly if vitamin D status and Ca intake are robust. We determined the effects of RYGB on intestinal fractional Ca absorption (FCA) while maintaining ample 25OHD levels (goal ≥30 ng/mL) and Ca intake (1200 mg daily) in a prospective cohort of 33 obese adults (BMI 44.7 ± 7.4 kg/m(2)). FCA was measured preoperatively and 6 months postoperatively with a dual stable isotope method. Other measures included calciotropic hormones, bone turnover markers, and BMD by DXA and QCT. Mean 6-month weight loss was 32.5 ± 8.4 kg (25.8% ± 5.2% of preoperative weight). FCA decreased from 32.7% ± 14.0% preoperatively to 6.9% ± 3.8% postoperatively (p < 0.0001), despite median (interquartile range) 25OHD levels of 41.0 (33.1 to 48.5) and 36.5 (28.8 to 40.4) ng/mL, respectively. Consistent with the FCA decline, 24-hour urinary Ca decreased, PTH increased, and 1,25(OH)2 D increased (p ≤ 0.02). Bone turnover markers increased markedly, areal BMD decreased at the proximal femur, and volumetric BMD decreased at the spine (p < 0.001). Those with lower postoperative FCA had greater increases in serum CTx (ρ = -0.43, p = 0.01). Declines in FCA and BMD were not correlated over the 6 months. In conclusion, FCA decreased dramatically after RYGB, even with most 25OHD levels ≥30 ng/mL and with recommended Ca intake. RYGB patients may need high Ca intake to prevent perturbations in Ca homeostasis, although the approach to Ca supplementation needs further study. Decline in FCA could contribute to the decline in BMD after RYGB, and strategies to avoid long-term skeletal consequences should be investigated.

Changes in vertebral bone marrow fat and bone mass after gastric bypass surgery: A pilot study

Bone marrow fat may serve a metabolic role distinct from other fat depots, and it may be altered by metabolic conditions including diabetes. Caloric restriction paradoxically increases marrow fat in mice, and women with anorexia nervosa have high marrow fat. The longitudinal effect of weight loss on marrow fat in humans is unknown. We hypothesized that marrow fat increases after Roux-en-Y gastric bypass (RYGB) surgery, as total body fat decreases. In a pilot study of 11 morbidly obese women (6 diabetic, 5 nondiabetic), we measured vertebral marrow fat content (percentage fat fraction) before and 6 months after RYGB using magnetic resonance spectroscopy. Total body fat mass declined in all participants (mean ± SD decline 19.1 ± 6.1 kg or 36.5% ± 10.9%, p<0.001). Areal bone mineral density (BMD) decreased by 5.2% ± 3.5% and 4.1% ± 2.6% at the femoral neck and total hip, respectively, and volumetric BMD decreased at the spine by 7.4% ± 2.8% (p<0.001 for all). Effects of RYGB on marrow fat differed by diabetes status (adjusted p=0.04). There was little mean change in marrow fat in nondiabetic women (mean +0.9%, 95% CI -10.0 to +11.7%, p=0.84). In contrast, marrow fat decreased in diabetic women (-7.5%, 95% CI -15.2 to +0.1%, p=0.05). Changes in total body fat mass and marrow fat were inversely correlated among nondiabetic (r=-0.96, p=0.01) but not diabetic (r=0.52, p=0.29) participants. In conclusion, among those without diabetes, marrow fat is maintained on average after RYGB, despite dramatic declines in overall fat mass. Among those with diabetes, RYGB may reduce marrow fat. Thus, future studies of marrow fat should take diabetes status into account. Marrow fat may have unique metabolic behavior compared with other fat depots.

Human islet viability and function is maintained during high-density shipment in silicone rubber membrane vessels

BACKGROUND

The shipment of human islets (IE) from processing centers to distant laboratories is beneficial for both research and clinical applications. The maintenance of islet viability and function in transit is critically important. Gas-permeable silicone rubber membrane (SRM) vessels reduce the risk of hypoxia-induced death or dysfunction during high-density islet culture or shipment. SRM vessels may offer additional advantages: they are cost-effective (fewer flasks, less labor needed), safer (lower contamination risk), and simpler (culture vessel can also be used for shipment).

METHOD

IE were isolated from two manufacturing centers and shipped in 10-cm(2) surface area SRM vessels in temperature- and pressure-controlled containers to a distant center after at least 2 days of culture (n = 6). Three conditions were examined: low density (LD), high density (HD), and a microcentrifuge tube negative control (NC). LD was designed to mimic the standard culture density for IE preparations (200 IE/cm(2)), while HD was designed to have a 20-fold higher tissue density, which would enable the culture of an entire human isolation in 1-3 vessels. Upon receipt, islets were assessed for viability (measured by oxygen consumption rate normalized to DNA content [OCR/DNA)]), quantity (measured by DNA), and, when possible, potency and function (measured by dynamic glucose-stimulated insulin secretion measurements and transplants in immunodeficient B6 Rag(+/-) mice). Postshipment OCR/DNA was not reduced in HD vs LD and was substantially reduced in the NC condition. HD islets exhibited normal function postshipment. Based on the data, we conclude that entire islet isolations (up to 400,000 IE) may be shipped using a single, larger SRM vessel with no negative effect on viability and ex vivo and in vivo function.

Laparoscopic sleeve gastrectomy is safe and efficacious for pretransplant candidates

BACKGROUND

Morbid obesity is a relative contraindication for organ transplant because it is associated with higher postoperative morbidity and mortality. The safety and efficacy of laparoscopic sleeve gastrectomy (LSG) as a weight loss method for patients awaiting transplant has not been examined.

METHODS

A retrospective review was performed on morbidly obese patients awaiting liver or kidney transplant who underwent LSG from 2006 to 2012. Data included patient demographic characteristics, operative details, 30-day complications, percentage of excess weight loss, postoperative laboratory data, and status of transplant candidacy.

RESULTS

Twenty-six pretransplant patients underwent LSG. The mean age was 57 years, and 17 (65%) were women. Six patients had end-stage renal disease, and 20 patients had end-stage liver disease. The preoperative mean body mass index was 48.3 kg/m(2) (range 38-60.4 kg/m(2)). There were no deaths, and there were 6 postoperative complications: 2 superficial wound infections, 1 staple line leak, 1 postoperative bleed requiring blood transfusion, 1 transient encephalopathy, and 1 temporary renal insufficiency. The mean percentage of excess weight loss at 1, 3, and 12 months was 17% (n = 24/26), 26% (n = 23/26), and 50% (n = 18/20), respectively. All patients met our institution's body mass index cutoffs for transplantation by 12 months after the procedure. One patient's renal function stabilized, and he was taken off the transplant list. Eight patients eventually underwent solid organ transplant. Six received liver transplants, 1 patient received a combined liver and kidney transplant, and 1 received a kidney transplant. The mean time between LSG and transplant was 16.6 months.

CONCLUSIONS

This is the largest case series involving LSG in patients awaiting solid organ transplantation. LSG is well tolerated, is technically feasible, and improves candidacy for transplantation.

Experience with laparoscopic donor nephrectomy among more than 1000 cases: low complication rates, despite more challenging cases

HYPOTHESIS

Despite the overall acceptance of laparoscopic donor nephrectomy (LDNX), concern remains about the application of this technique in certain complex situations, such as right-sided nephrectomies and in donors with complex kidney anatomy and obese donors. This study was designed to determine if complication rates have remained stable as we have offered LDNX to all medically acceptable donors and to analyze the results of cases in each of the complex categories. We hypothesized that complication rates in the 3 complex categories would be equivalent to those among more straightforward cases.

DESIGN

Retrospective medical record review.

SETTING

Academic medical center.

PATIENTS

A total of 1045 patients who underwent LDNX between November 3, 1999, and August 28, 2009.

MAIN OUTCOMES MEASURES

Operative times, lengths of hospital stay, overall complications, major complications, conversions to open surgery, blood transfusions, readmissions, and reoperations.

RESULTS

The outcomes of the first 250 patients (when LDNX was selectively offered) were compared with the outcomes of the last 795 patients (when LDNX was offered to all medically acceptable donors). Overall operative times significantly improved (212 vs 176 minutes), overall complication rates did not change (6.4% vs 5.5%), and major complication rates significantly declined (4.0% vs 1.4%). Among the last 795 patients, 1 conversion to open surgery and 1 blood transfusion occurred. There were no deaths in the series. Moreover, no differences in overall or major complication rates were seen when cases involving 200 right-sided nephrectomies, 204 donors with complex kidney anatomy, and 148 obese donors were analyzed independently.

CONCLUSIONS

Low complication rates persist for LDNX, even when applied to more technically challenging cases. This procedure is offered to all medically acceptable donors, with an excellent safety profile, and should be considered the standard of care for kidney donation.

Islet transplantation in type 1 diabetic patients using calcineurin inhibitor-free immunosuppressive protocols based on T-cell adhesion or costimulation blockade

BACKGROUND

The applicability of islet transplantation as treatment for type 1 diabetes is limited by long-term graft dysfunction, immunosuppressive drug toxicity, need for multiple donors, and increased risk of allosensitization. We describe two immunosuppressive regimens based on the costimulation blocker belatacept (BELA) or the antileukocyte functional antigen-1 antibody efalizumab (EFA), which permit long-term islet allograft survival and address some of these concerns.

METHODS

Ten patients with type 1 diabetes with hypoglycemic unawareness received intraportal allogeneic islet transplants. Immunosuppression consisted of antithymocyte globulin induction and maintenance with sirolimus or mycophenolate and BELA (n=5) or EFA (n=5).

RESULTS

All five BELA-treated patients achieved independence after single transplants; one resumed partial insulin use 305 days after transplant but is now independent after a second transplant. All five patients treated with EFA achieved independence after one (3/5) or two (2/5) islet transplants and remained independent while on EFA (392-804 days). After EFA was discontinued because of withdrawal of the drug from the market, two patients resumed intermittent insulin use; the others remain independent. No patient in either group developed significant side effects related to the study drugs, and none have been sensitized to alloantigens. All have stable renal function.

CONCLUSIONS

These two novel immunosuppressive regimens are effective, well tolerated, and the first calcineurin inhibitor/steroid-sparing islet protocols resulting in long-term insulin independence. Although EFA is no longer available for clinical use, these early results demonstrate that a regimen using BELA may be an effective alternative to improve graft function and longevity while minimizing renal and β-cell toxicity.

Islet transplantation in type 1 diabetics using an immunosuppressive protocol based on the anti-LFA-1 antibody efalizumab

The applicability of islet transplantation as treatment for type 1 diabetes is limited by renal and islet toxicities of currently available immunosuppressants. We describe a novel immunosuppressive regimen using the antileukocyte functional antigen-1 antibody efalizumab which permits long-term islet allograft survival while reducing the need for corticosteroids and calcineurin inhibitors (CNI). Eight patients with type 1 diabetes and hypoglycemic unawareness received intraportal allogeneic islet transplants. Immunosuppression consisted of antithymocyte globulin induction followed by maintenance with efalizumab and sirolimus or mycophenolate. When efalizumab was withdrawn from the market in mid 2009, all patients were transitioned to regimens consisting of mycophenolate and sirolimus or mycophenolate and tacrolimus. All patients achieved insulin independence and four out of eight patients became independent after single-islet transplants. Insulin independent patients had no further hypoglycemic events, hemoglobin A1c levels decreased and renal function remained stable. Efalizumab was well tolerated and no serious adverse events were encountered. Although long-term follow-up is limited by discontinuation of efalizumab and transition to conventional imunnosuppression (including CNI in four cases), these results demonstrate that insulin independence after islet transplantation can be achieved with a CNI and steroid-free regimen. Such an approach may minimize renal and islet toxicity and thus further improve long-term islet allograft survival.

Clinical islet transplantation at the University of California, San Francisco

The UCSF clinical islet transplant program has evolved to utilize immunosuppressive strategies that do not rely on CNIs or other nephro- and beta-cell-toxic immunosuppressive agents. These novel strategies depend on lymphocyte-depleting induction immunotherapy and maintenance immunosuppression with novel agents that focus on co-stimulation and/or lymphocyte migration blockade. These drugs are well tolerated, frequently allow establishment of insulin independence after single islet infusions, and minimize allosensitization. Our early results suggest these regimens will be attractive immunosuppressive agents for future protocols in allogeneic islet transplantation as well as protocols utilizing stem-cell-derived beta cells.

Portomesenteric venous thrombosis after laparoscopic surgery: a systematic literature review

BACKGROUND

Portomesenteric venous thrombosis (PVT) is an uncommon but potentially lethal condition reported after several laparoscopic procedures. Its presentation, treatment, and outcomes remain poorly understood, and possible etiologic factors include venous stasis from increased intra-abdominal pressure, intraoperative manipulation, or damage to the splanchnic endothelium and systemic thrombophilic states.

DESIGN

Systematic literature review.

SETTING

Academic research.

SUBJECTS

We summarized the clinical presentation and outcomes of PVT after laparoscopic surgery other than splenectomy in 18 subjects and reviewed the treatment strategies.

MAIN OUTCOME MEASURES

Systematic review of the literature on PVT after laparoscopic procedures other than splenectomy.

RESULTS

Eighteen cases of PVT following laparoscopic procedures were identified after Roux-en-Y gastric bypass (n = 7), Nissen fundoplication (n = 5), partial colectomy (n = 3), cholecystectomy (n = 2), and appendectomy (n = 1). The mean patient age was 42 years (age range, 20-74 years). Systemic predispositions toward venous thrombosis were identified in 11 patients. Clinical symptoms consisted primarily of abdominal pain manifested, on average, 14 days (range, 3-42 days) after surgery. Thrombus location varied, but 8 patients had a combination of portal and superior mesenteric venous thrombosis. Sixteen patients were treated with anticoagulation therapy. Ten patients underwent major interventions, including exploratory laparotomy in 6 patients and thrombolytic therapy in 4 patients. Six patients had complications, and 2 patients died.

CONCLUSIONS

Portomesenteric venous thrombosis following laparoscopic surgery usually manifests as nonspecific abdominal pain. Computed tomography can readily provide the diagnosis and demonstrate the extent of the disease. Treatment should be individualized based on the extent of thrombosis and the presence of bowel ischemia but should include anticoagulation therapy. Venous stasis from increased intra-abdominal pressure, intraoperative manipulation of splanchnic vasculature, and systemic thrombophilic states likely converges to produce this potentially lethal condition.

Long-term renal function and cardiovascular disease risk in obese kidney donors

BACKGROUND AND OBJECTIVES

Increasing demand for live-donor kidneys has encouraged the use of obese donors despite the absence of long-term outcome data and evidence that obesity can adversely affect renal function. We wished to determine whether obesity increased the risk for renal dysfunction and other medical comorbidities in donors several years after donation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Ninety-eight patients who donated a kidney 5 to 40 years previously were stratified according to body mass index (BMI) at donation and evaluated for renal dysfunction and risk factors for cardiovascular disease. Patients who were from the 2005 through 2006 National Health and Nutrition Examination Survey database; did not have renal disease; and were matched for age, gender, race, and BMI served as two-kidney control subjects.

RESULTS

Renal function in obese (BMI > or =30) and nonobese (BMI <30) donors was similar, and both donor groups had reduced renal function compared with BMI-matched two-kidney control subjects. Obesity was associated with more hypertension and dyslipidemias in both donors and two-kidney control subjects; however, there were no significant differences between the two groups within each BMI category.

CONCLUSIONS

These results indicate that obese donors are not at higher risk for long-term reduced renal function compared with nonobese donors and that the increased incidence of hypertension and other cardiovascular disease risk factors in obese donors is due to their obesity and is not further exacerbated by nephrectomy. These findings support the current practice of using otherwise healthy overweight and obese donors but emphasize the need for more intensive preoperative education and postoperative health care maintenance in this donor group.

A clinical scoring system for predicting nonalcoholic steatohepatitis in morbidly obese patients

Nonalcoholic steatohepatitis (NASH) is common in morbidly obese persons. Liver biopsy is diagnostic but technically challenging in such individuals. This study was undertaken to develop a clinically useful scoring system to predict the probability of NASH in morbidly obese persons, thus assisting in the decision to perform liver biopsy. Consecutive subjects undergoing bariatric surgery without evidence of other liver disease underwent intraoperative liver biopsy. The outcome was pathologic diagnosis of NASH. Predictors evaluated were demographic, clinical, and laboratory variables. A clinical scoring system was constructed by rounding the estimated regression coefficients for the independent predictors in a multivariate logistic model for the diagnosis of NASH. Of 200 subjects studied, 64 (32%) had NASH. Median body mass index was 48 kg/m(2) (interquartile range, 43-55). Multivariate analysis identified six predictive factors for NASH: the diagnosis of hypertension (odds ratio [OR], 2.4; 95% confidence interval [CI], 1-5.6), type 2 diabetes (OR, 2.6; 95% CI, 1.1-6.3), sleep apnea (OR, 4.0; 95% CI, 1.3-12.2), AST > 27 IU/L (OR, 2.9; 95% CI, 1.2-7.0), alanine aminotransferase (ALT) > 27 IU/L (OR, 3.3; 95% CI, 1.4-8.0), and non-Black race (OR, 8.4; 95% CI, 1.9-37.1). A NASH Clinical Scoring System for Morbid Obesity was derived to predict the probability of NASH in four categories (low, intermediate, high, and very high).

CONCLUSION

The proposed clinical scoring can predict NASH in morbidly obese persons with sufficient accuracy to be considered for clinical use, identifying a very high-risk group in whom liver biopsy would be very likely to detect NASH, as well as a low-risk group in whom biopsy can be safely delayed or avoided.

Laparoscopic bariatric surgery improves candidacy in morbidly obese patients awaiting transplantation

BACKGROUND

To evaluate, at a university tertiary referral center, the safety and efficacy of laparoscopic Roux-en-Y gastric bypass (LRYGB) in patients with end-stage renal disease (ESRD) and laparoscopic sleeve gastrectomy (LSG) in patients with cirrhosis or end-stage lung disease (ESLD); and to determine whether these procedures help patients become better candidates for transplantation.

METHODS

A retrospective review was performed of selected patients with end-stage organ failure who were not eligible for transplantation because of morbid obesity who underwent LRYGB or LSG. The prospectively collected data included demographics, operative details, complications, percentage of excess weight loss, postoperative laboratory data, and status of transplant candidacy.

RESULTS

Of the 15 patients, 7 with ESRD underwent LRYGB and 6 with cirrhosis and 2 with ESLD underwent LSG. Complications developed in 2 patients (both with cirrhosis); no patient died. The mean follow-up was 12.4 months, and the mean percentage of excess weight loss at > or =9 months was 61% (ESRD), 33% (cirrhosis), and 61.5% (ESLD). Obesity-associated co-morbidities improved or resolved in all patients. Serum albumin and other nutritional parameters at > or =9 months after surgery were similar to the preoperative levels in all 3 groups. At the most recent follow-up visit, 14 (93%) of 15 patients had reached our institution's body mass index limit for transplantation and were awaiting transplantation; 1 patient with ESLD underwent successful lung transplant.

CONCLUSION

The results of this pilot study have provided preliminary evidence that LRYGB in patients with ESRD and LSG in patients with cirrhosis or ESLD is safe, well-tolerated, and improves their candidacy for transplantation.

The impact of roux limb length on weight loss after gastric bypass

BACKGROUND

Extending the length of the Roux limb (RL) in gastric bypass (GBP) may improve weight loss in super obese patients (body mass index [BMI] > 50 kg/m(2)), but no consensus exists about the optimal length of the RL. We sought to determine the impact of RL length on weight loss in super obese patients 1 year after GBP.

MATERIALS AND METHODS

One-year weight loss outcomes were analyzed in all super obese patients who underwent consecutive and primary laparoscopic or open GBP between January 2003 and June 2006. Patients were divided into two groups according to RL length (100 vs. 150 cm). The RL length was at the discretion of the attending surgeon. Baseline and follow-up data were collected prospectively. Multiple linear regression was used to adjust for potential confounders in the weight loss outcomes.

RESULTS

Twelve-month follow-up data were available in 137 (85%) of 161 patients with a BMI >or= 50 who underwent GBP during the study period. An RL of 100 or 150 cm was used in 102 (74.5%) and 35 patients (25.5%), respectively. In multivariate analysis, patients with the 150-cm RL lost more weight (68.5 vs. 55.3 kg, p < 0.01), had a greater change in BMI (25 vs. 21 kg/m(2), p = 0.01), and had greater excess weight loss (64 vs. 53%, p < 0.01).

CONCLUSION

A 150-cm RL provides better weight loss outcomes in super obese patients at 1-year follow-up.

Predictors, treatment, and outcomes of gastrojejunostomy stricture after gastric bypass for morbid obesity

BACKGROUND

The aims of this study were to determine the rate of gastrojejunostomy (GJ) stricture following Roux-en-Y gastric bypass (RYGBP), the independent predictors of stricture, and clinical outcomes with and without a stricture.

METHODS

Univariate and multivariate analysis of peri-operative and outcomes data were prospectively collected from 379 morbidly obese patients who underwent consecutive open or laparoscopic RYGBP from January 2003 to August 2006. Predictors studied were age, gender, BMI, co-morbidities, surgical technique (hand-sewn vs linear stapler vs 21-mm vs 25-mm circular stapler; open vs laparoscopic; retrocolic retrogastric vs antecolic antegastric Roux limb course, and Roux limb length), and surgeon experience. Outcomes studied consisted of occurrence of GJ strictures, technical details and outcomes after endoscopic therapy, and excess weight loss (EWL) at 12 months.

RESULTS

15 patients (4.1%) developed a GJ stricture. The use of a 21-mm circular stapler was identified as the only independent predictor of a GJ stricture (odds ratio 11.3; 95% CI 2.2-57.4, P = 0.004). Endoscopic dilation relieved stricture symptoms in all patients (60% one dilation only). There was no significant difference in %EWL at 12 months between the patients with a stricture (median EWL 54%, IQR 49-63) vs. those without a stricture (median EWL 61%, ent predictor of GJ stricture. Endoscopic dilation relieved symptoms in all patients. Weight loss is independent of the anastomotic technique used and occurrence of a GJ stricture.

Catheter-directed therapy for DVT after pancreas transplantation

INTRODUCTION

Iliac vein deep venous thrombosis (DVT) ipsilateral to the pancreas transplant can lead to severe leg edema and compromise graft function. Treatment modalities for iliac vein DVT in the pancreas transplant recipient are limited.

METHODS

Medical records of patients receiving pancreas transplants at a single center from November 1989 to July 2003 were reviewed retrospectively, identifying patients with iliac vein DVT. There were 287 pancreas transplants performed during this time. Pancreas transplantation in all recipients was performed in the right iliac fossa with the arterial supply consisting of a donor iliac artery Y interposition graft. Systemic venous drainage was to the iliac vein. Exocrine drainage was enteric or to the bladder.

RESULTS

Four (1.4%) cases of iliac DVT were identified. All patients manifested lower extremity edema ipsilateral to the pancreas transplant. DVT was detected by ultrasound on days 4, 5, 13, and 60 post-transplant. In all cases, the iliac vein caudad to the pancreatic venous anastomosis was noted to be stenotic. Management involved balloon dilatation and endovascular stent placement in one patient, thrombolysis with tissue plasma antigen (t-PA) followed by stent placement in one patient, and percutaneous mechanical thrombectomy in two patients. All patients had improvement in leg edema and two patients continue to have good pancreatic allograft function.

CONCLUSIONS

Iliac DVT is a rare complication of pancreas transplantation that usually develops in an area of stenosis caudad to the pancreatic venous anastomosis. Catheter-based treatment modalities with use of endovascular stents for treatment of underlying stenoses can serve as an adjunct in treating these complications.

Spectrum and risk factors of complications after gastric bypass

OBJECTIVE

To study the spectrum of and risk factors for complications after gastric bypass (GBP).

DESIGN

Prospective cohort study.

SETTING

Academic tertiary referral center.

PATIENTS

All morbidly obese patients who underwent open or laparoscopic GBP between January 2003 and December 2006.

MAIN OUTCOME MEASURES

Complications were stratified by grade: grade I, only bedside procedure; grade II, therapeutic intervention but without lasting disability; grade III, irreversible deficits; and grade IV, death. Data were analyzed using logistic regression to identify independent risk factors of complications after GBP. Predictors investigated were age, race, sex, marital and insurance status, body mass index, obesity-associated comorbidities, American Society of Anesthesiologists Physical Status Class, operating room time, open or laparoscopic approach, and surgeon experience.

RESULTS

Of the 404 morbidly obese patients who underwent consecutive open (n = 72) or laparoscopic (n = 332) GBP, 74 (18.3%) experienced 107 complications. Grade I and II complications were more frequent after open GBP (grade I, 19.4% after open vs 3.9% after laparoscopic operations, P < .001; grade II, 20.8% after open vs 8.4% after laparoscopic operations, P < .001), and 55% were wound related. Grades III and IV complications occurred in only 4 patients (1%), and frequency was similar for open and laparoscopic cases. Three factors were independently predictive of complications: diabetes mellitus (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.1-3.3; P = .02), early surgeon experience (OR, 2.5; 95% CI, 1.4-4.2; P = .001), and open approach (OR, 3.9; 95% CI, 2.1-7.3; P < .001).

CONCLUSIONS

Complications occurred in 18.3% of patients, but 95% were treated without leading to lasting disability. Presence of diabetes, early surgeon experience, and an open approach are risk factors of complications.

Routine upper GI series after gastric bypass does not reliably identify anastomotic leaks or predict stricture formation

BACKGROUND

Many surgeons who perform Roux-en-Y gastric bypass (RYGB) for morbid obesity routinely obtain an upper gastrointestinal (GI) series in the early postoperative period to search for anastomotic leaks and signs of stricture formation at the gastrojejunostomy. We hypothesized that this practice is unreliable.

METHODS

We analyzed 654 consecutive RYGBs, of which 63% were completed laparoscopically. An upper GI series was obtained in 634 (97%) patients. The radiographic findings (leak or delayed emptying) were compared with clinical outcomes (leak or stricture formation) to calculate the sensitivity and specificity. Univariate analysis identified risk factors for leaks or stricture formation; events were too few for multivariate analysis.

RESULTS

Of 634 routine upper GI series, anastomotic leaks at the gastrojejunostomy were diagnosed in 5 (0.8%); 2 of these 5 were later reinterpreted as artifacts. Four leaks were not seen on the initial upper GI series, yielding an overall sensitivity of 43% and a positive predictive value (PPV) of 60%. Univariate analysis showed that cases done early (odds ratio [OR] 5.4 for the first 100 cases, p = 0.02) and prolonged operating time (OR 7.8 for cases >or= 300 min, p = 0.01) were associated with leaks. Emptying into the Roux-en-Y limb was delayed in 127 (20%) of the upper GI series. Strictures requiring dilatation developed in 16 (2.4%) patients. The PPV of delayed emptying for stricture formation was 6%. Risk factors for stricture formation included stapled anastomosis (OR 7.8, p = 0.002), surgeon inexperience (OR 2.9 for first 50 cases, p = 0.04), and delayed emptying (OR 3.3; p = 0.02).

CONCLUSIONS

Because the incidence of anastomotic complications and the sensitivity of upper GI series were both low, routine upper GI series did not reliably identify leaks or predict stricture formation. A selective approach, whereby imaging is reserved for patients with clinical evidence of a leak or stricture, may be more appropriate.

Antibody-mediated rejection of a pancreas allograft

The role of antibody-mediated rejection (AMR) in pancreas transplantation is poorly understood. Here, we report on a patient who developed AMR of his pancreas allograft after receiving a simultaneous pancreas-kidney transplant. Pre-operative enhanced cytotoxicity and flow cytometry T-cell crossmatches were negative; B-cell crossmatches were not performed as per institutional protocol. The patient's post-operative course was significant for elevated serum amylase levels and development of hyperglycemia approximately 1 month after transplantation. A pancreatic biopsy at this time showed no cellular infiltrate but strong immunofluorescent staining for C4d in the interacinar capillaries. Analysis of the patient's serum identified donor-specific HLA-DR alloantibodies. He received intravenous immunoglobulin (IVIg), rituximab and plasmapheresis, and his pancreatic function normalized. We conclude that clinically significant AMR can develop in a pancreas allograft and recommend that pancreatic biopsies be assessed for C4d deposition if the patient has risk factors for AMR and/or the pathologic evidence for cell-mediated rejection is underwhelming.

Laparoscopic procurement of kidneys with multiple renal arteries is associated with increased ureteral complications in the recipient

This study investigates the effect of renal artery multiplicity on donor and recipient outcomes after laparoscopic donor nephrectomy. Three-hundred and sixty-one sequential procedures were performed over a 4-year period. Forty-nine involved accessory renal arteries; of these, 36 required revascularization and 13 were small polar vessels and ligated. The 312 remaining kidneys with single arteries served as controls. Study variables included operative times, blood loss, hospital stay, graft function and donor and recipient complications. Kidneys with multiple revascularized arteries had a longer mean warm ischemia time (35.3 vs. 29.2 min, p = 0.0003), and more ureteral complications (6/36 vs. 10/312, p = 0.0013) than single-artery controls. In contrast, ligation of a small superior accessory artery had no significant effect on donor operative time, blood loss, or complication rate while providing similar recipient graft function compared to single-artery controls. Renal artery number is important in selecting the appropriate kidney for laparoscopic procurement. Given the current excellent results with right-sided donor nephrectomy, kidneys with single arteries should be preferentially procured, irrespective of side.

BKV in simultaneous pancreas-kidney transplant recipients: a leading cause of renal graft loss in first 2 years post-transplant

With the introduction of more potent immunosuppressive agents, rejection has decreased in simultaneous pancreas/kidney transplant (SPK) recipients. However, as a consequence, opportunistic infections have increased. The purpose of this report is to outline the course of SPK patients who developed polyomavirus-associated nephropathy (PVAN). A retrospective review of 146 consecutive SPK recipients from January 1, 1996 to December 31, 2002 was performed. Immunosuppression, rejection and development of PVAN were reviewed. Nine patients were identified. All received induction with either OKT3 or thymoglobulin. Immunosuppression included tacrolimus/cyclosporine, MMF/azathioprine and sirolimus/prednisone. Two patients were treated for kidney rejection prior to the diagnosis of PVAN. Time to diagnosis was an average of 359.3 days post-transplantation. Immunosuppression was decreased but five ultimately lost function. However, none developed pancreatic abnormalities as demonstrated by normal glucose and amylase. Two underwent renal retransplantation after PVAN diagnosis and both have normal kidney function. PVAN was the leading cause of renal loss in SPK patients in the first 2 years after transplantation and is a serious concern for SPK recipients. The pancreas, however, is spared from evidence of infection, and no pancreatic rejection occurred when immunosuppression was decreased.