Pancreatic transplantation: surgical technique, normal radiological appearances and complications

Ultrasound of pancreatic transplant complications: a primer for radiologists

Pancreatic transplantation is an established treatment for patients with type 1 diabetes patients and select type 2 diabetes patients, with excellent survival rates as graft health is evaluated through regular imaging and early detection of complications. Amongst the various imaging methods that may aid in diagnosis of pancreatic transplant complications, ultrasound is a widely available, quick, portable, and cost-effective technique, often used as the sole method to assess for pancreatic transplant complications. When assessing a patient with a pancreatic transplant, the radiologist should be methodical in assessing the vasculature, the pancreatic parenchyma, and the peripancreatic regions. Complications can be categorised based on time from transplant and type of complications, and include vascular, parenchymal, and enteric/anastomotic complications. Doppler has a major role in the diagnosis of vascular complications including arterial and venous thrombosis, arterial stenosis, pseudoaneurysms, and haematomas. Pancreatic complications include rejections and pancreatitis, and are often diagnosed through a combination of clinical, laboratory, and imaging findings, such as pancreatic heterogeneity or the presence of pancreatic pseudocysts. Enteric/anastomotic complications include leaks and bowel obstructions, and may require cross-sectional imaging in addition to ultrasound. This review covers the most common and high-impact vascular, parenchymal, and enteric/anastomotic complications that should be considered in every radiologist's search pattern when assessing a pancreatic graft, as well as their respective postoperative timeframes.

Novel technique for arterial reconstruction in simultaneous pancreas-kidney transplantation, a randomized clinical trial

INTRODUCTION

Simultaneous pancreas kidney (SPK) transplantation is an invaluable procedure to enhance the quality of life of insulin-dependent patients with advanced renal disease. The creation of vascular anastomoses of the donor's pancreas vessels to the recipient's, is of utmost importance to predict the graft outcome and surgical complications. In the study we introduce a novel technique for arterial reconstruction during SPK transplantation.

METHODS

Conventionally, during the SPK transplantation, a so-called Y-graft is anastomosed between donor's superior mesenteric and splenic artery to the recipient's right iliac artery. In the study we adopted a new technique by preparing an extra extension using the donor's carotid artery, to be anastomosed to the Y-graft and the iliac artery. In this non-blinded randomized clinical trial we compared the surgical complications and early outcomes between the 2 groups of patients with the traditional and new arterial reconstruction techniques during 3 months after transplantation.

RESULTS

Thirty adult patients were included in the study. The incidence of pancreatitis, vascular thrombosis and surgical site infection was lower in the new Y-graft and extension technique, which was not statistically significant. However, the calculated Cohen's d index showed the medium effect of new Y-graft and extension technique on complication after SPK transplantations.

CONCLUSION

The post-operative complications tend to be lower in the novel arterial reconstruction technique, however a study on a larger patient group is encouraged to confirm our primary results.

TRIAL REGISTRATION

The study was registered at the Iranian Registry of Clinical Trials on 12/05/2022; IRCT 20210625051701N2; ( http://www.irct.ir/ ).

Pancreatic Transplantation: Surgical Anatomy and Complications

Pancreatic transplantation is a complex surgical procedure performed for patients with chronic severe diabetes, often performed in combination with renal transplantation. Vascular and exocrine drainage anatomy varies depending on the surgical technique. Radiology plays a critical role in the diagnosis of postoperative complications, requiring an understanding of grayscale/Doppler ultrasound as well as computed tomography and MR imaging. In this review, we detail usual surgical methods and normal postoperative imaging appearances. We then review the most common complications following pancreatic transplants, emphasizing diagnostic features of vascular (arterial/venous), surgical, and diffuse parenchymal pathologic conditions on multiple imaging modalities.

The Presence of Activated T Cell Subsets prior to Transplantation Is Associated with Increased Rejection Risk in Pancreas Transplant Recipients

Pancreas and islet transplantation (PTx) are currently the only curative treatment options for type 1 diabetes. CD4⁺ and CD8⁺ T cells play a pivotal role in graft function, rejection, and survival. However, characterization of immune cell status from patients with and without rejection of the pancreas graft is lacking. We performed multiparameter immune phenotyping of T cells from PTx patients prior to and 1 y post-PTx in nonrejectors and histologically confirmed rejectors. Our results suggest that rejection is associated with presence of elevated levels of activated CD4⁺ and CD8⁺ T cells with a gut-homing phenotype both prior to and 1 y post-PTx. The CD4⁺ and CD8⁺ T cells were highly differentiated, with elevated levels of type 1 inflammatory markers (T-bet and INF-γ) and cytotoxic components (granzyme B and perforin). Furthermore, we observed increased levels of activated FOXP3⁺ regulatory T cells in rejectors, which was associated with a hyporesponsive phenotype of activated effector T cells. Finally, activated T and B cell status was correlated in PTx patients, indicating a potential interplay between these cell types. In vitro treatment of healthy CD4⁺ and CD8⁺ T cells with tacrolimus abrogated the proliferation and cytokine (INF-γ, IL-2, and TNF-α) secretion associated with the type 1 inflammatory phenotype observed in pre- and post-PTx rejectors. Together, our results suggest the presence of activated CD4⁺ and CD8⁺ T cells prior to PTx confer increased risk for rejection. These findings may be used to identify patients that may benefit from more intense immunosuppressive treatment that should be monitored more closely after transplantation.

The effect of immunosuppressive therapy after liver transplantation on activities of daily living and fear of death during the COVID-19 pandemic

BACKGROUND

In our study, we aimed to investigate the effect of immunosuppressive therapy after liver transplantation on activities of daily living and fear of death during the COVID-19 pandemic.

METHODS

This study was conducted as a cross-sectional study with the participation of 213 liver transplant patients hospitalized in the liver transplant center of a university hospital. The data analysis was performed with IBM SPSS (Statistical Package for the Social Sciences) Statistics 25.

RESULTS

Katz's Activities of Daily Living (ADL) were semi-independent and the total score was 11.07 ± 1.59, and the Death Attitude Profile-Revised (DAP-R) total score was 152.23 ± 5.34. It was determined that the DAP-R score was around 150 points in the minimum and maximum score ranges of Katz ADL after liver transplantation.

CONCLUSIONS

High fear of death threatens resilience and can make patients feel lonely, helpless, sad, abandoned and stressed. Clinicians should spend more time with their patients.

The effect of immunosuppression therapy on activities of daily living and comfort level after liver transplantation

OBJECTIVES

This study was carried out to investigate the effect of immunosuppression therapy on activities of daily living and comfort level after liver transplantation.

MATERIALS AND METHODS

This study was conducted in a descriptive and correlational type with the participation of 148 liver transplant patients hospitalized in the liver transplant center of a university hospital. Personal Information Form, Katz Activities of Daily Living Scale and General Comfort Questionnaire were used in data collection. The data analysis was performed with IBM SPSS (Statistical Package for the Social Sciences) Statistics 25.

RESULTS

According to the results obtained from the study, it was determined that 31.1% of the patients were 58 years old and over, 20.9% of them were between 48- and 57 years old, and 81.8% of them were male. It was found that 61.5% of the patients were between the 11th and 21st days after transplantation and 26.4% of them were given oxygen with a non-invasive catheter. It was determined that the patients were semi-independent in activities of daily living and had a moderate comfort level.

CONCLUSIONS

It is not always possible for liver transplant patients to effectively deal with their condition. The low comfort level and quality of life of patients who have undergone liver transplantation should be noticed, and social, economic and psychological support should be provided.

Critical presentation and management of an acute gastrointestinal haemorrhage as a result of an arterioenteric fistula secondary to a failed pancreatic allograft

We present a case of a 60-year-old woman status post failed pancreatic transplant, presenting with right lower extremity pain and large volume rectal bleeding. The team initiated a massive transfusion protocol. Investigations revealed an arterioenteric (AE) fistula between the right external iliac artery and terminal ileum. The patient was then emergently sent for right iliac artery stent placement, successfully stopping the active arterial haemorrhage. Afterwards, the surgical team transected the pancreatic jejunal anastomosis, subsequently resecting 7 cm of jejunum. On postoperative day 1, the patient became unstable, going into disseminated intravascular coagulation evidenced by low platelet count, elevated prothrombin time and bloody output from multiple sites. Resuscitation with pressors and blood product transfusion was unsuccessful. She was made comfort measures only and expired shortly after extubation. Although a rare aetiology, it is important to consider AE fistulas in patients presenting with vascular and gastrointestinal symptoms in the setting of a failed allograft.

Lotus-root-shaped cell-encapsulated construct as a retrieval graft for long-term transplantation of human iPSC-derived β-cells

Cell therapy using human-stem-cell-derived pancreatic beta cells (hSC-βs) is a potential treatment method for type 1 diabetes mellitus (T1D). For therapeutic safety, hSC-βs need encapsulation in grafts that are scalable and retrievable. In this study, we developed a lotus-root-shaped cell-encapsulated construct (LENCON) as a graft that can be retrieved after long-term hSC-β transplantation. This graft had six multicores encapsulating hSC-βs located within 1 mm from the edge. It controlled the recipient blood glucose levels for a long-term, following transplantation in immunodeficient diabetic mice. LENCON xenotransplanted into immunocompetent mice exhibited retrievability and maintained the functionality of hSC-βs for over 1 year after transplantation. We believe that LENCON can contribute to the treatment of T1D through long-term transplantation of hSC-βs and in many other forms of cell therapy.

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A lotus-root-shaped cell-encapsulated construct as a retrieval graft

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Advantages in terms of FBR mitigation and mechanical strength as a graft

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Control the recipient blood glucose levels of NOD-Scid mice for up to half a year

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Retrieval without adhesion over 1 year after transplantation

Management of vascular and nonvascular complications following pancreas transplantation with interventional radiology

Pancreas transplantation exposes to high rates of complications, either vascular (thrombosis, stenosis, pseudoaneurysm, arteriovenous fistula) or nonvascular (fluid collection, graft rejection). With advances in percutaneous and endovascular techniques, interventional radiologists are increasingly involved in the management of these complications. In this article, we review the anatomical considerations relevant to pancreas transplantation, the techniques used for image-guided interventions for vascular and nonvascular complications, and the expected outcomes of these interventions.

Incidence and Outcomes of Significant Weight Changes After Pancreas Transplant Alone

Background.

Weight change, primarily weight gain, is a common problem among solid organ transplant recipients. The incidence of weight gain or loss after successful pancreas transplant alone (PTA) and the effect on graft survival is unknown.

Methods.

This was a single-center observational study among PTA recipients, transplanted at our center between January 1, 2005, and July 31, 2017, who had a functional pancreas graft for at least 1 year and documented weight change at the 1-year clinic visit.

Results.

In this cohort study of 105 PTA recipients, 28 had significant weight gain, 27 had significant weight loss, and the remaining 50 did not have significant weight change at 1-year posttransplant. When comparing the weight gain and no weight change groups, the weight gain cohort started to gain weight at 3 months posttransplant to 5 years or last follow up. Similarly, the weight loss group lost weight at 3 months posttransplant up to last follow up. Clinically significant weight gain or weight loss were not associated with uncensored or death censored graft failure in univariate regression and Kaplan-Meier survival analysis. Also, there were no significant differences between the groups in the glycated hemoglobin at last follow up.

Conclusions.

Approximately 50% of PTA recipients had a significant weight change at 1-year posttransplant, of which 25% gained significant weight and 25% loss. There was no significant difference in graft survival due to the significant weight changes. Further research is needed in this field.

Challenges of pancreas transplantation in developing countries, exploring the Turkey example

Pancreas transplantation significantly improves the quality of life for people with type 1 diabetes, primarily by eliminating the need for insulin and frequent blood glucose measurements. Despite the growing numbers of solid organ transplantations worldwide, number of pancreas transplantations in the developing countries` remain significantly low. This difference of pancreas transplantation practices was striking among the participating countries at the 1st International Transplant Network Meeting which was held in Turkey on 2018. In this meeting more than 40 countries were represented. Most of these counties were developing countries located in Africa, Middle East or Asia. The aim of this article is to identify the challenges and limiting factors for pancreas transplantations in these developing countries, by exploring the Turkish example. The challenges faced by the developing countries are broadly classified in four categories; wait-listing, donor pool, team work and follow up. Under these categorical titles, issues are further discussed in detail, giving examples from Turkish practice of pancreas transplantation. Additionally, several solutions to these challenges have been proposed- some of which have already been undertaken by the Turkish Ministry of Health. With the insight and methods presented in this article, pancreas transplantation should be made possible for the potential recipients in the developing countries.

Effects of Periodic Intensive Insulin Therapy: An Updated Review

Background

Traditional insulin treatment for diabetes mellitus with insulin administered subcutaneously yields nonpulsatile plasma insulin concentrations that represent a fraction of normal portal vein levels. Oral hypoglycemic medications result in the same lack of pulsatile insulin response to blood glucose levels. Intensive treatments of significant complications of diabetes are not recommended due to complicated multidrug regimens, significant weight gain, and the high risk of hypoglycemic complications. Consequently, advanced complications of diabetes do not have an effective treatment option because conventional therapy is not sufficient. Intensive insulin therapy (IIT) simulates normal pancreatic function by closely matching the periodicity and amplitude of insulin secretion in healthy subjects; however, the mechanisms involved with the observed improvement are not clearly understood.

Objective

The current review aims to analyze the pathophysiology of insulin secretion, discuss current therapies for the management of diabetes, provides an updates on the recent advancements of IIT, and proposes its mechanism of action.

Methods

A literature search on PubMed, MEDLINE, Embase, and CrossRef databases was performed on multiple key words regarding the history and current variations of pulsatile and IIT for diabetes treatment. Articles reporting the physiology of insulin secretion, advantages of pulsatile insulin delivery in patients with diabetes patients, efficacy and adverse effects of current conventional insulin therapies for the management of diabetes, benefits and shortcomings of pancreas and islet transplantation, or clinical trials on patients with diabetes treated with pulsed insulin therapy or advanced IIT were included for a qualitative analysis and categorized into the following topics: mechanism of insulin secretion in normal subjects and patients with diabetes and current therapies for the management of diabetes, including oral hypoglycemic agents, insulin therapy, pancreas and islet transplantation, pulsed insulin therapy, and advances in IIT.

Results

Our review of the literature shows that IIT improves the resolution of diabetic ulcers, neuropathy, and nephropathy, and reduces emergency room visits. The likely mechanism responsible for this improvement is increased insulin sensitivity from adipocytes, as well as increased insulin receptor expression.

Conclusions

Recent advancements show that IIT is an effective option for both type 1 diabetes mellitus and type 2 diabetes mellitus patient populations. This treatment resembles normal pancreatic function so closely that it has significantly reduced the effects of relatively common complications of diabetes in comparison to standard treatments. Thus, this new treatment is a promising advancement in the management of diabetes. (Curr Ther Res Clin Exp. 2019; 80:XXX–XXX).

An unusual presentation of gastric fistula following peptic perforation repair: A case report

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Late onset Gastrocutaneous fistulas are rare following the peptic perforation repair.

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A non-healing burst abdominal wound should be thoroughly investigated. It can be because of an underlying fistula.

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CT fistulogram is the investigation of choice to confirm the diagnosis.

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Operative intervention is difficult but the only method of cure in most of the circumstances.

Introduction

Peptic perforation repair is a common stomach surgery. This surgery has not been associated with delayed onset gastrocutaneous fistula formation. However such a complication has been reported following a variety of other stomach surgeries. We are reporting this case as it is a rare complication. Also its diagnosis and management is challenging.

Case summary

We are presenting a case of peptic perforation repair where burst abdomen happened in the immediate post-operative period. The patient was put on conservative management. He responded well to it but his abdominal wound was not healing. After a wait of four months the wound was covered with a skin graft. The graft uptake was satisfactory but a discharging ulcer appeared on it. This condition persisted for one month. Finally a computed tomography Fistulogram (CT Fistulogram) was performed. It revealed an underlying complex gastric fistula. A repeat surgery was performed.

Conclusion

A gastrocutaneous fistula diagnosed at sixth month following the peptic perforation repair and causing minimal discomfort to the patient is a rare presentation. The abdominal wound following the surgery was possibly not healing because of the underlying fistula.

Immunosuppression following organ transplantation. Part 1: mechanisms and immunosuppressive agents

Solid organ transplantation has revolutionised medical care by providing a definitive cure for a wide spectrum of end-stage medical conditions. This treatment, however, does not come without complications and poses the risks of rejection, life-threatening infection, malignancies and recurrent organ failure, with significant impacts on patient outcomes. One of the major challenges involved in optimising post-transplant outcomes is managing the immune system's response to the transplanted graft and preventing organ rejection. This is mainly accomplished through the use of immunosuppressant agents, which have become a mainstay of treatment for a majority of post-transplant patients. This article, the first of two parts, discusses the concept of immunosuppression and its importance in the care of patients who have received an organ transplant. It focuses on the pathophysiologic mechanisms involved in transplant rejection and discusses the pharmacologic aspects of immunosuppression and its implications for patient care.

Gastrointestinal Bleeding Secondary to Iliac Artery Pseudoaneurysm in a Patient With Remote Pancreas Transplant: A Case Report

BACKGROUND

Vascular complications represent the most common cause of early graft failure after pancreatic transplantation (PT). Pseudoaneurysms are uncommon vascular complications that usually present within the first year post transplantation.

CASE REPORT

A 49-year-old man with history of type 1 diabetes mellitus presented for evaluation with a 2-day history of painless hematochezia. He had undergone PT 4 years prior to presentation, which failed due to acute cellular rejection after 1 year. Both extended upper endoscopy and colonoscopy did not identify an active bleeding source. After an episode of massive hematochezia, he became hemodynamically unstable with peritoneal signs noted on physical examination. An abdominal angiogram was unable to identify active hemorrhage, and the patient was transferred to the operating room for open laparotomy. Exploration revealed a right common iliac artery pseudoaneurysm eroding into the pancreatic-ileal anastomosis, which required initial digital compression for initial hemostasis. After combined endovascular procedure with ballooning and stenting of the right iliac artery, optimal hemostasis was achieved without further episodes of hematochezia.

DISCUSSION

Gastrointestinal bleeding (GIB) has been reported to occur in 11% of enteric-drained PT. Even though infectious causes have been reported, culprits are more commonly associated with vascular or enteric surgical anastomosis and usually occur within the early postoperative course. Here we report an uncommon cause of GIB, a late complication of PT, and review important points associated with the management of GIB, anatomy of PT, and potential etiologies for early and late GIB in the setting of PT.

Imaging in pancreas transplantation complications: Temporal classification

Pancreatic transplantation is a therapeutic option for both poorly controlled cases of diabetes mellitus and patients with advanced diabetic nephropathy. It is important for radiologists to know the different surgical techniques as well as the typical radiological appearance after pancreatic transplantation, in order to accurately identify the complications. These complications can be classified according to the period of time after the transplantation in which they typically occur: immediate (first 24 hours), early (24-72 hours), intermediate (72 hours to weeks) and late (months). An accurate and early diagnosis of pancreas transplantation complications is essential to start the adequate treatment and increase the chances of graft survival.

Imaging of Pancreas Transplantation and Its Complications

Whole pancreas transplantation is an effective treatment for obtaining euglycemic status in patients with insulin-dependent diabetes mellitus, and is usually performed concurrent with renal transplantation in the affected patient. This article discusses complex surgical anatomical details of pancreas transplantation including surgical options for endocrine and exocrine drainage pathways. It then describes several possible complications related to surgical factors in the immediate post operative period followed by other complications related to systemic issues, vasculature, and the pancreatic parenchyma.

Conservative Pancreas Graft Preservation at the Extreme

Because of the value some patients place in remaining insulin-independent after pancreas transplantation, they may be reluctant to undergo graft pancreatectomy, even in the face of extreme complications, such as graft thrombosis and duodenal segment leak. Partly, for this reason, a variety of complex salvage techniques have been described to save the graft in such circumstances. We report a case of a series of extreme complications related to a leak from the duodenal segment after a simultaneous pancreas and kidney transplant. These included infected thrombosis of the inferior vena cava associated with a graft venous thrombosis and a retroperitoneal fistula. The patient retained graft function with insulin independence and repeatedly declined graft pancreatectomy against the advice of the transplant team. Conservative treatment with percutaneous drainage, antibiotics, and anticoagulation was eventually successful. This outcome is unique in our experience and may be instructive to teams caring for pancreas transplant recipients.

The use of venous jump grafts in pancreatic transplantation - no difference in patient or allograft outcomes - an update of the UNOS database

Venous jump grafts are used in pancreas transplantation to salvage a pancreas with a short portal vein or to facilitate an easier anastomosis. There have been no large studies evaluating the safety of venous jump grafts in pancreas transplantation. We analyzed the UNOS database to determine whether venous jump grafts are associated with graft loss or patient death. Data from UNOS on all adult pancreas transplant recipients 1996-2012 were analyzed. Venous extension grafts were used in 2657 cases; they were not in 18 124. Kaplan-Meier/product-limit estimates analysis demonstrated similar patient survival (p < 0.641) and death-censored graft survival (p < 0.351) at one, three, five,10, and 15 yr between subjects with and without venous jump grafts. There was a statistically significant difference in one-yr unadjusted patient survival between the venous extension graft (94.9%) and the no-venous extension graft (95.8%) groups (p < 0.045) and a borderline difference in one-yr graft survival between the venous extension graft (84.1%) and the no-venous extension graft (82.6%) groups (p < 0.055). There was no significant difference in patient survival or allograft survival at the three-, five-, 10-, and 15-yr intervals. The use of venous jump grafts is not associated with increased graft loss or mortality.