The impact of bacterial colonization on graft success after total pancreatectomy with autologous islet transplantation: considerations for early definitive surgical intervention

A bioengineered artificial interstitium supports long-term islet xenograft survival in nonhuman primates without immunosuppression

Cell-based therapies hold promise for many chronic conditions; however, the continued need for immunosuppression along with challenges in replacing cells to improve durability or retrieving cells for safety are major obstacles. We subcutaneously implanted a device engineered to exploit the innate transcapillary hydrostatic and colloid osmotic pressure generating ultrafiltrate to mimic interstitium. Long-term stable accumulation of ultrafiltrate was achieved in both rodents and nonhuman primates (NHPs) that was chemically similar to serum and achieved capillary blood oxygen concentration. The majority of adult pig islet grafts transplanted in non-immunosuppressed NHPs resulted in xenograft survival >100 days. Stable cytokine levels, normal neutrophil to lymphocyte ratio, and a lack of immune cell infiltration demonstrated successful immunoprotection and averted typical systemic changes related to xenograft transplant, especially inflammation. This approach eliminates the need for immunosuppression and permits percutaneous access for loading, reloading, biopsy, and recovery to de-risk the use of "unlimited" xenogeneic cell sources to realize widespread clinical translation of cell-based therapies.

Effect of intraoperative fluid type on postoperative systemic inflammatory response and end organ dysfunction following total pancreatectomy with islet autotransplantation in children

PURPOSE

To evaluate the effect of intraoperative fluid type [half normal saline (0.45NS) or lactated Ringer's solution (LR)] on the risk of systemic inflammatory response syndrome (SIRS) and acute kidney injury after total pancreatectomy with islet autotransplantation in children.

METHODS

Retrospective review where demographics, operative details, systemic inflammatory response, and evaluation for end organ dysfunction over the first 5 postoperative days was obtained. Mixed effects Poisson regression compared risk of SIRS and acute kidney injury by intraoperative fluid type.

RESULTS

Forty three patients were included with no difference in demographic characteristics between groups. SIRS was observed in 95, 77, and 71% over post operative days 1, 3, and 5. Intraoperative fluid type was found to not be associated with postoperative SIRS (RR: 0.91, p = 0.23). However, female sex (RR: 1.30, p < 0.01), increased BMI (RR: 1.08, p < 0.01), and longer operative time (RR: 1.07, p < 0.01) were found to be factors that are associated with increased risk of postoperative SIRS. Intraoperative 0.45NS use was associated with increased acute kidney injury compared to LR on postoperative day 1 (52% vs 0%, p < 0.01), but not on postoperative days 3 or 5.

CONCLUSION

Intraoperative fluid type (0.45NS vs LR) does not increase the risk of postoperative SIRS in children after TPIAT. Predictive factors that are associated with an increased risk of eliciting postoperative SIRS includes female sex, increased BMI, and longer operative times.

LEVEL OF EVIDENCE

III.

Pharmacological management of patients undergoing total pancreatectomy with auto-islet transplantation

Chronic pancreatitis results in permanent parenchymal destruction of the pancreas gland leading to anatomical and physiological consequences for patients. Surgical management varies, and some patients require total pancreatectomy with autologous islet cell transplantation (TPIAT). Patients undergoing TPIAT require complex and diligent management after surgery. This encompasses the management of glucose control (endocrine function of the pancreas) and supplementing loss of exocrine function of the pancreas with digestive enzymes. Other areas of management include optimizing pain relief while reducing narcotic usage, providing antimicrobial prophylaxis, and reducing loss of islet cells by improving its integrity through anticoagulation and use of anti-inflammatory agents. Each aspect of care is unique to this population. However, comprehensive reviews on its pharmacological management are scarce. This review will discuss the available literature to date surrounding all aspects of pharmacological management of patients undergoing TPIAT.

Clinical Significance of Postoperative Antibiotic Treatment for Positive Islet Cultures After Total Pancreatectomy With Islet Autotransplantation

OBJECTIVES

Islet cultures are routinely performed in total pancreatectomy with islet autotransplantation (TPIAT), and the need for empiric antibiotic treatment based on culture results is unknown. We evaluated the effect of postoperative antibiotic treatment for positive islet cultures on clinical infection.

METHODS

Seventy-nine patients undergoing TPIAT were reviewed. Prophylactic perioperative ceftriaxone and metronidazole were administered, and transplanted islet preparations included ciprofloxacin. Postoperative antibiotics were not routinely given for positive cultures unless a clinical infection was suspected. The primary end point was 30-day infectious complications.

RESULTS

Fifty-one patients (65%) had a positive culture. Overall, 39 patients (87%) had organisms susceptible to our perioperative antibiotic regimen. There was no difference in the infectious complication rate between those with positive compared with negative cultures (16% vs 29%, P = 0.17). Patients with a positive culture had similar 30-day postoperative infectious complication rates whether receiving postoperative antibiotics (n = 7) or not (14% vs 16%, P = 0.91). Only 1 patient had a correlation of clinical and islet cultures.

CONCLUSIONS

Beyond prophylactic antibiotics, empiric antibiotic treatment for a positive culture is not warranted and provides a rationale for the abandonment of routine cultures in TPIAT.

Total Pancreatectomy with Autologous Islet Cell Transplantation-The Current Indications

Total pancreatectomy is a major complex surgical procedure involving removal of the whole pancreatic parenchyma and duodenum. It leads to lifelong pancreatic exocrine and endocrine insufficiency. The control of surgery-induced diabetes (type 3) requires insulin therapy. Total pancreatectomy with autologous islet transplantation (TPAIT) is performed in order to prevent postoperative diabetes and its serious complications. It is very important whether it is safe and beneficial for patients in terms of postoperative morbidity and mortality, and long-term results including quality of life. Small duct painful chronic pancreatitis (CP) is a primary indication for TPAIT, but currently the indications for this procedure have been extended. They also include hereditary/genetic pancreatitis (HGP), as well as less frequent indications such as benign/borderline pancreatic tumors (intraductal papillary neoplasms, neuroendocrine neoplasms) and “high-risk pancreatic stump”. The use of TPAIT in malignant pancreatic and peripancreatic neoplasms has been reported in the worldwide literature but currently is not a standard but rather a controversial management in these patients. In this review, history, technique, indications, and contraindications, as well as short-term and long-term results of TPAIT, including pediatric patients, are described.

Preoperative ERCP has no impact on islet yield following total pancreatectomy and islet autotransplantation (TPIAT): Results from the Prospective Observational Study of TPIAT (POST) cohort

BACKGROUND AND AIMS

Many patients undergoing total pancreatectomy with islet autotransplant (TPIAT) for severe, refractory chronic pancreatitis or recurrent acute pancreatitis have a history of endoscopic retrograde cholangiopancreatography (ERCP). Using data from the multicenter POST (Prospective Observational Study of TPIAT) cohort, we aimed to determine clinical characteristics associated with ERCP and the effect of ERCP on islet yield.

METHODS

Using data from 230 participants (11 centers), demographics, pancreatitis history, and imaging features were tested for association with ERCP procedures. Logistic and linear regression were used to assess association of islet yield measures with having any pre-operative ERCPs and with the number of ERCPs, adjusting for confounders.

RESULTS

175 (76%) underwent ERCPs [median number of ERCPs (IQR) 2 (1-4). ERCP was more common in those with obstructed pancreatic duct (p = 0.0009), pancreas divisum (p = 0.0009), prior pancreatic surgery (p = 0.005), and longer disease duration (p = 0.004). A greater number of ERCPs was associated with disease duration (p < 0.0001), obstructed pancreatic duct (p = 0.006), and prior pancreatic surgery (p = 0.006) and increased risk for positive islet culture (p < 0.0001). Mean total IEQ/kg with vs. without prior ERCP were 4145 (95% CI 3621-4669) vs. 3476 (95% CI 2521-4431) respectively (p = 0.23). Adjusting for confounders, islet yield was not significantly associated with prior ERCP, number of ERCPs, biliary or pancreatic sphincterotomy or stent placement.

CONCLUSIONS

ERCP did not appear to adversely impact islet yield. When indicated, ERCP need not be withheld to optimize islet yield but the risk-benefit ratio of ERCP should be considered given its potential harms, including risk for excessive delay in TPIAT.

Improved harmonization of critical characterization assays across cell therapies

The field of cell therapy has blossomed, providing exciting new options for treating a variety of diseases. While few cell therapy products have US FDA approval, there are thousands of cell treatments at various stages of development, pointing to a potential revolutionary shift in patient care. The expanding number and nature of cellular therapies necessitate greater standardization. Several international organizations are collaborating to pursue some level of global standardization, especially concerning cell banking. However, less harmonization surrounds assays used for critical quality characterization including: identity, purity, safety and potency. Frequently, there is divergence regarding the terms describing the characterization assays across regulatory authorities and guidances. This review summarizes the critical quality assays currently used for different categories of cell therapies. Areas of harmonization and an absence of standardization are highlighted. We propose potential solutions to facilitate harmonization of critical quality characterization assays and the language used to describe them.

Islet cell transplantation in children

This paper aims to provide an overview of islet cell transplantation in children, with specific attention to pediatric total pancreatectomy with islet autotransplantation (TPIAT). We will summarize the definition and causes of chronic pancreatitis in children, the TPIAT procedure and potential complications, the process of islet cell isolation and autotransplantation, and long-term results after TPIAT. Lastly, we will briefly discuss islet cell allotransplantation in the adult population and its potential role in treating children.

Impact of microbial contamination of the islet product during total pancreatectomy with islet autotransplantation

BACKGROUND

The combined use of interleukin-1β and tumor necrosis factor-α blockers in the peritransplant period has improved outcomes of total pancreatectomy with islet autotransplantation (TPIAT). However, these drugs may suppress the immune system, resulting in severe infection.

METHODS

We retrospectively investigated the impact of microbial-contaminated islet product on posttransplant complications and metabolic outcomes of TPIAT patients receiving the IL-1β and TNF-blockade treatment at our center.

RESULTS

Among 108 TPIAT patients, 37 patients (34%) received contaminated products. Preoperative stent treatment and fibrosis score were independent risk factors for the contamination. There were no significant differences between the contaminated and noncontaminated product groups in posttransplant infectious complication rate, length of hospitalization, or readmission rate. However, islet equivalents (P < .0001) and insulin independence rate (P = .036) at 6 months were significantly lower for patients receiving contaminated product.

CONCLUSIONS

These results suggest that combined anti-inflammatory drug use is safe and well tolerated in TPIAT patients who receive contaminated islet product and does not increase the rate of infectious complications; however, contaminated islet product is associated with poor metabolic outcomes.

Early Infectious Complications After Total Pancreatectomy with Islet Autotransplantation: a Single Center Experience

INTRODUCTION

We assessed whether positive microbiological cultures from the islet preparation had any effect on the risk of infectious complications (IC) after total pancreatectomy with islet autotransplantation (TPIAT) in our center.

METHODS

We analyzed preservation fluid and final islet product surveillance cultures with reference to clinical data of patients undergoing TPIAT. All patients received routine prophylactic broad-spectrum antibiotics.

RESULTS

The study involved 10 men and 18 women with a median age of 39 years. Over 30% of surveillance cultures during pancreas processing grew bacterial strains with predominantly polymicrobial contaminations (13 of 22 (59%)). At least one positive culture was identified in almost half of the patients (46%) undergoing TPIAT and a third had both surveillance cultures positive. Infectious complications affected 50% of patients. After excluding cases of PICC line-associated bacteremia/fungemia present on admission, incidence of IC was higher in cases of positive final islet product culture than in those with negative result (57% vs. 21%), which also corresponded with the duration of chronic pancreatitis (p = 0.04). Surgical site infections were the most common IC, followed by fever of unknown origin. There was no concordance between pathogens isolated from the pancreas and those identified during the infection.

CONCLUSIONS

While IC was common among TPIAT patients, we found no concordance between pathogens isolated from the pancreas and those identified during infection. Contamination of the final islet product was of clinical importance and could represent a surrogate marker for higher susceptibility to infection.

Microbial Contamination, Infection, and Antimicrobial Use During Total Pancreatectomy With Islet Autotransplantation

OBJECTIVES

Total pancreatectomy with islet autotransplantation can relieve pain associated with chronic pancreatitis while preserving islet function. Islet preparations are often contaminated by enteric flora. We assessed the impact of contaminated islet preparations on the prevalence of postoperative infection.

METHODS

Electronic health records for patients who underwent total pancreatectomy with islet autotransplantation from August 1, 2011, to November 15, 2017 were retrospectively reviewed to compare the prevalence of postoperative infection in patients with a positive islet culture and islet culture negative patients.

RESULTS

Sixty-one patients were included. Twenty-nine patients (47.5%) had a positive islet culture, and 23 (79.3%) of these patients received antimicrobial prophylaxis. The prevalence of postoperative infection did not differ between the islet culture positive and islet culture negative groups (41% vs 34%, P = 0.57). No infections occurred in the 6 islet culture positive patients who did not receive prophylaxis. No difference in intensive care unit or hospital length of stay or in 30-day or 90-day readmission rates were observed.

CONCLUSIONS

Despite the common use of postoperative systemic antimicrobials, we observed no difference in the prevalence of postoperative infection, length of stay, or hospital readmission in patients receiving a contaminated islet preparation. If prophylactic antimicrobials are used, the duration should be minimized.

Geographical variance in reporting of elective surgery for chronic pancreatitis

The selection of optimum surgical procedure from the range of reported operations for chronic pancreatitis (CP) can be difficult. The aim of this study is to explore geographical variation in reporting of elective surgery for CP. A systematic search of the literature was performed using the Scopus database for reports of five selected procedures for CP: duodenum-preserving pancreatic head resection, total pancreatectomy with islet autotransplantation (TPIAT), Frey pancreaticojejunostomy, thoracoscopic splanchnotomy and the Izbicki V-shaped resection. The keyword and MESH heading 'chronic pancreatitis' was used. Overall, 144 papers met inclusion criteria and were utilized for data extraction. There were 33 reports of duodenum-preserving pancreatic head resection. Twenty-one (64%) were from Germany. There were 60 reports of TPIAT, 53 (88%) from the USA. There are only two reports of TPIAT from outwith the USA and UK. The 34 reports of the Frey pancreaticojejunostomy originate from 12 countries. There were 20 reports of thoracoscopic splanchnotomy originating from nine countries. All three reports of the Izbicki 'V' procedure are from Germany. There is geographical variation in reporting of surgery for CP. There is a need for greater standardization in the selection and reporting of surgery for patients with painful CP.

Total pancreatectomy and islet autotransplantion for chronic and recurrent acute pancreatitis

PURPOSE OF REVIEW

We reviewed the current state of total pancreatectomy with islet autotransplantation (TPIAT) for chronic pancreatitis and recurrent acute pancreatitis (RAP).

RECENT FINDINGS

An increasing number of centers in the United States and internationally are performing TPIAT. In selected cases, TPIAT may be performed partially or entirely laparoscopically. Islet isolation is usually performed at the same center as the total pancreatectomy surgery, but new data suggest that diabetes outcomes may be nearly as good when a remote center is used for islet isolation. Ongoing clinical research is focused on patient and disease factors that predict success or failure to respond to TPIAT. Causes of persistent abdominal pain after TPIAT may include gastrointestinal dysmotility and central sensitization to pain. Several clinical trials are underway with anti-inflammatory or other islet protective strategies to better protect islets at the time of infusion and thereby improve the diabetes results of the procedure.

SUMMARY

In summary, there is an increasing body of literature emerging from multiple centers highlighting the benefits and persistent challenges of TPIAT for chronic pancreatitis and RAP. Ongoing study will be critical to optimizing the success of this procedure.

Pancreas preservation fluid microbial contamination is associated with poor islet isolation outcomes - a multi-centre cohort study

The microbiological safety of islet preparations is paramount. Preservation medium contamination is frequent, and its impact on islet yield and function remains unclear. Microbiological samples collected during islet isolations from 2006 to 2016 were analyzed and correlated to isolation and allo- and autotransplantation outcomes. Microbial contamination of preservation medium was found in 64.4% of processed donor pancreases (291/452). We identified 464 microorganisms including Staphylococcus (253/464, 54.5%), Streptococcus (31/464, 6.7%), and Candida species (25/464, 5.4%). Microbial contamination was associated with longer warm and cold ischemia times and lower numbers of postpurification islet equivalents, purity, transplant rate, and stimulation index (all P < 0.05). Six percent of the preparations accepted for transplantation showed microbial contamination after isolation (12/200); 9 of 12 were Candida species. Six patients were transplanted with a sample with late microbial growth discovered after the infusion. Insulin independence rate was not affected. This risk of transplanting a contaminated islets preparation was reduced by half following the implementation of an additional sampling after 24 h of islet culture. Pancreas preservation fluid microbial contamination is associated with lower transplant rate and poorer in vitro function, but not with changes in graft survival. Culture medium testing 1 day after isolation reduces the risk of incidental transplantation with contaminated islets.

Salvage Islet Auto Transplantation After Relaparatomy

BACKGROUND

To assess feasibility, safety, and metabolic outcome of islet auto transplantation (IAT) in patients undergoing completion pancreatectomy because of sepsis or bleeding after pancreatic surgery.

METHODS

From November 2008 to October 2016, approximately 22 patients were candidates to salvage IAT during emergency relaparotomy because of postpancreatectomy sepsis (n = 11) or bleeding (n = 11). Feasibility, efficacy, and safety of salvage IAT were compared with those documented in a cohort of 36 patients who were candidate to simultaneous IAT during nonemergency preemptive completion pancreatectomy through the pancreaticoduodenectomy.

RESULTS

The percentage of candidates that received the infusion of islets was significantly lower in salvage IAT than simultaneous IAT (59.1% vs 88.9%, P = 0.008), mainly because of a higher rate of inadequate islet preparations. Even if microbial contamination of islet preparation was significantly higher in candidates to salvage IAT than in those to simultaneous IAT (78.9% vs 20%, P < 0.001), there was no evidence of a higher rate of complications related to the procedure. Median follow-up was 5.45 ± 0.52 years. Four (36%) of 11 patients reached insulin independence, 6 patients (56%) had partial graft function, and 1 patient (9%) had primary graft nonfunction. At the last follow-up visit, median fasting C-peptide was 0.43 (0.19-0.93) ng/mL; median insulin requirement was 0.38 (0.04-0.5) U/kg per day, and median HbA1c was 6.6% (5.9%-8.1%). Overall mortality, in-hospital mortality, metabolic outcome, graft survival, and insulin-free survival after salvage IAT were not different from those documented after simultaneous IAT.

CONCLUSIONS

Our data demonstrate the feasibility, efficacy, and safety of salvage IAT after relaparotomy.

Total Pancreatectomy With Islet Autotransplantation for Acute Recurrent and Chronic Pancreatitis

PURPOSE OF REVIEW

The first total pancreatectomy and islet autotransplantation (TP-IAT) was performed for chronic pancreatitis in 1977 with the goal to ameliorate the pain and simultaneously preserve islet function. We reviewed the recent medical literature regarding indications, patient suitability, current outcomes, and challenges in TP-IAT.

RECENT FINDINGS

Current indications for TP-IAT include intractable pain secondary to chronic pancreatitis (CP) or acute recurrent pancreatitis (ARP) with failed medical and endoscopic/surgical management. Independent studies have shown that TP-IAT is associated with elimination or significant improvement in pain control and partial or full islet graft function in the majority of patients. In single-center cost analyses, TP-IAT has been suggested to be more cost-effective than medical management of chronic pancreatitis. While initially introduced as a surgical option for adults with long-standing chronic pancreatitis, TP-IAT is now often utilized in children with chronic pancreatitis and in children and adults with intractable acute recurrent pancreatitis. The surgical procedure has evolved over time with some centers offering minimally invasive operative options, although the open approach remains the standard. Despite many advances in TP-IAT, there is a need for further research and development in disease diagnosis, patient selection, optimization of surgical technique, islet isolation and quality assessment, postoperative patient management, and establishment of uniform metrics for data collection and multicenter studies. TP-IAT is an option for patients with otherwise intractable acute recurrent or chronic pancreatitis which presents potential for pain relief and improved quality of life, often with partial or complete diabetes remission.

Pediatric pancreas transplantation, including total pancreatectomy with islet autotransplantation

Unlike other solid-organ transplants, whole pancreas transplantation in children is relatively rare, and it occurs more frequently in the context of multivisceral or composite organ transplantation. Because children only infrequently suffer severe sequelae of type 1 diabetes mellitus, pancreas transplantation is rarely indicated in the pediatric population. More commonly, pediatric pancreas transplant occurs in the setting of incapacitating acute recurrent or chronic pancreatitis, specifically islet autotransplantation after total pancreatectomy. In this clinical scenario, total pancreatectomy removes the nidus of chronic pain and debilitation, while autologous islet transplantation aims to preserve endocrine function. The published experiences with pediatric total pancreatectomy with islet autotransplantation (TPIAT) in children has demonstrated excellent outcomes including liberation from chronic opioid use, as well as improved mental and physical quality of life with good glycemic control. Given the complexity of the operation, risk of postoperative complication, and long-term physiologic changes, appropriate patient selection and comprehensive multidisciplinary care teams are critical to ensuring optimal outcomes.