Pancreatic and biliary stents

Pilot study on cultural and metagenomic analysis of bile and biliary stentslead to unveiling the key players in stent occlusion

Endoscopic Retrograde Cholangio-Pancreatography (ERCP) with biliary stenting is a minimally invasive medical procedure employed to address both malignant and benign obstructions within the biliary tract. Benign biliary strictures (BBSs), typically arising from surgical interventions such as liver transplants and cholecystectomy, as well as chronic inflammatory conditions, present a common clinical challenge. The current gold standard for treating BBSs involves the periodic insertion of plastic stents at intervals of 3-4 months, spanning a course of approximately one year. Unfortunately, stent occlusion emerges as a prevalent issue within this treatment paradigm, leading to the recurrence of symptoms and necessitating repeated ERCPs. In response to this clinical concern, we initiated a pilot study, delving into the microbial composition present in bile and on the inner surfaces of plastic stents. This investigation encompassed 22 patients afflicted by BBSs who had previously undergone ERCP with plastic stent placement. Our preliminary findings offered promising insights into the microbial culprits behind stent occlusion, with Enterobacter and Lactobacillus spp. standing out as prominent bacterial species known for their biofilm-forming tendencies on stent surfaces. These revelations hold promise for potential interventions, including targeted antimicrobial therapies aimed at curtailing bacterial growth on stents and the development of advanced stent materials boasting anti-biofilm properties.

Lumen-apposing metal stents versus traditional self-expanding metal stents for endoscopic ultrasound-guided drainage of pancreatic fluid collections: a systematic review and meta-analysis

BACKGROUND

Endoscopic drainage has become the preferred treatment for pancreatic fluid collections (PFCs). There is still a lack of reliable evidence to prove which metal stent is the best choice for endoscopic ultrasound (EUS)-guided drainage of PFCs. In this study, we aimed to evaluate the efficacy and safety of lumen-apposing metal stents (LAMS) compared to traditional self-expanding metal stents (SEMS) in meta-analysis.

METHODS

We systematically searched PubMed, Embase, Web of Science, and Cochrane Library up to July 15, 2023. Relevant publications that compared LAMS with traditional SEMS for drainage of patients' PFCs under EUS-guidance were included. This meta-analysis assessed endpoints using Review Manager 5.3 and Stata 14.0 statistical software.

RESULT

Nine citations comprising 707 patients with PFCs were included. The clinical success rate of LAMS tended to be higher than that of SEMS (RR = 1.07, 95%CI [1.00, 1.15], P = 0.05). LAMS had a lower technical success rate (RR = 0.97, 95%CI [0.94, 0.99], P = 0.02) and faster procedure time (minutes) (MD =  - 24.29, 95%CI [- 25.59, - 22.99], P < 0.00001) compared to SEMS. In addition, LAMS had fewer overall adverse events (RR = 0.64, 95%CI [0.48, 0.87], P = 0.004). For specific adverse events, LAMS had fewer migration (RR = 0.37, 95%CI [0.19, 0.72], P = 0.003), occlusion (RR = 0.43, 95%CI [0.22, 0.82], P = 0.01) and infection (RR = 0.38, 95%CI [0.20, 0.70], P = 0.002). There was no significant difference in bleeding and perforation between the two stents. For hospital stay (days), LAMS group was similar to SEMS group (MD =  - 3.34, 95%CI [- 7.71, - 1.03], P = 0.13). Regarding recurrence, LAMS group was fewer than SEMS group (RR = 0.41, 95%CI [0.21, 0.78], P = 0.007).

CONCLUSION

Compared to traditional SEMS, LAMS has a higher clinical success rate, faster procedure time, fewer adverse events, similar hospital stay and lower recurrence rate in EUS-guided drainage of PFCs. LAMS is a good choice with a high technical success rate over 95%, and using a shorter length or "one-step" operation can further improve it. Richer placement experience is required for LAMS placement under EUS-guidance.

A clinician's guide to gallstones and common bile duct (CBD): A study protocol for a systematic review and evidence-based recommendations

Background and Aims

Gallstones are one of the most common and costly diseases of the gastrointestinal tract and occur when a combination of deposits consisting of fat or minerals accumulate in the gallbladder or common bile duct (CBD). This paper provides a comprehensive review of gallstone epidemiology, diagnosis, and management, focusing on current clinical guidelines and evidence-based approaches.

Methods

A systematic literature review gathered information from various sources, including PubMed, Trip, Google Scholar, Clinical Key, and reputable medical association websites. Keywords related to gallstones, CBD stones, cholelithiasis, choledocholithiasis, and guidelines were used to extract relevant recommendations. Expert consultations and consensus meetings localized the recommendations based on the target population and available resources.

Results

The paper discusses demographic factors, dietary habits, and lifestyle influences contributing to gallstone formation. Gallstones are categorized into cholesterol and pigment types, with varying prevalences across regions. Many individuals with gallstones remain asymptomatic, but complications can lead to serious and potentially life-threatening conditions. Diagnosis relies on history, physical examination, laboratory tests, and transabdominal ultrasound. Specific predictive factors help categorize patients into high, moderate, or low probability groups for CBD stones.

Conclusion

Evidence-based recommendations for gallstone diagnosis and management are presented, emphasizing individualized treatment plans. Surgical interventions, nonsurgical treatments like oral litholysis with UDCA, and stenting are discussed. The management of gallstones in pregnant women is also addressed, considering the potential risks and appropriate treatment options during pregnancy.

Drainage Approach for Malignant Biliary Obstruction: A Changing Paradigm

Endoscopic retrograde cholangiopancreatography (ERCP) is the standard of care in the management of unresectable malignant biliary obstruction. However, endoscopic ultrasound (EUS)-guided biliary drainage has become widely accepted over the past several years for complicated biliary drainage in cases when ERCP is unsuccessful or not feasible. Recent emerging evidence suggests EUS-guided hepaticogastrostomy and EUS-guided choledochoduodenostomy are noninferior, and possibly even superior to conventional ERCP for primary palliation of malignant biliary obstruction. This article reviews the procedural techniques and considerations of the different techniques as well as comparative literature on safety and efficacy between techniques.

MRI safety screening of children with implants: updates and challenges

MRI is the imaging modality of choice for assessing many pediatric medical conditions. Although there are several inherent potential safety risks associated with the electromagnetic fields exploited for MRI, they are effectively mitigated through strict adherence to established MRI safety practices, enabling the safe and effective use of MRI in clinical practice. The potential hazards of the MRI environment may be exacerbated by/in the presence of implanted medical devices. Awareness of the unique MRI safety and screening challenges associated with these implanted devices is critical to ensuring MRI safety for the affected patients. In this review article, we will discuss the basics of MRI physics as they relate to MRI safety in the presence of implanted medical devices, strategies for assessing children with known or suspected implanted medical devices, and the particular management of several well-established common, as well as recently developed, implanted devices encountered at our institution.

Endoscopic luminal stenting: Current applications and future perspectives

Endoscopic luminal stenting (ELS) represents a minimally invasive option for the management of malignant obstruction along the gastrointestinal tract. Previous studies have shown that ELS can provide rapid relief of symptoms related to esophageal, gastric, small intestinal, colorectal, biliary, and pancreatic neoplastic strictures without compromising cancer patients’ overall safety. As a result, in both palliative and neoadjuvant settings, ELS has largely surpassed radiotherapy and surgery as a first-line treatment modality. Following the abovementioned success, the indications for ELS have gradually expanded. To date, ELS is widely used in clinical practice by well-trained endoscopists in managing a wide variety of diseases and complications, such as relieving non-neoplastic obstructions, sealing iatrogenic and non-iatrogenic perforations, closing fistulae and treating post-sphincterotomy bleeding. The abovementioned development would not have been achieved without corresponding advances and innovations in stent technology. However, the technological landscape changes rapidly, making clinicians’ adaptation to new technologies a real challenge. In our mini-review article, by systematically reviewing the relevant literature, we discuss current developments in ELS with regard to stent design, accessories, techniques, and applications, expanding the research basis that was set by previous studies and highlighting areas that need to be further investigated.

Fully Covered Metal Stents Safely Facilitate Extraction of Difficult Bile Duct Stones

BACKGROUND

Ten to 15% of the common bile duct (CBD) stones require advanced endoscopic extraction techniques during endoscopic retrograde cholangiopancreatography. The study aimed to evaluate the efficacy and safety of fully covered self-expandable metal stents (FC-SEMS) for facilitating the extraction of difficult bile duct stones.

METHODS

Patients who received FC-SEMS for the extraction of difficult CBD stones were retrospectively reviewed. Group 1 included patients with extrahepatic stones above a distal CBD stricture, Group 2 included patients with intrahepatic stones above a hilar stricture, and Group 3 included patients with complex stone(s) and no biliary stricture. Complete stone clearance rate and complications of FC-SEMS treatment were evaluated.

RESULTS

The study group included 33 procedures on 32 patients (mean age: 55±17, 56.3% male). FC-SEMS was placed as a primary treatment in 15 (45.5%) procedures. Complete stone clearance was achieved in 84.6% of the procedures in Group 1, 100% in Group 2, and 87.5% in Group 3 ( P =0.23). Overall, complete stone clearance was achieved in 30 of the 33 procedures (90.9%). None of the patients developed pancreatitis, cholecystitis, or cholangitis. Stent migration occurred in 4 procedures (12.1%), and all were clinically insignificant.

CONCLUSION

FC-SEMS is effective and safe for facilitating treatment of difficult bile duct stones.

Potential significance of uncovered self‐expandable metal stents for distal malignant biliary obstruction: A propensity score‐adjusted competing risk regression analysis

Objectives

Selection criteria for self‐expandable metal stents (SEMSs) with or without cover during palliative treatment of distal malignant biliary obstruction (DMBO) remain unclear. We evaluated factors associated with time to recurrent biliary obstruction (TRBO) in fully covered SEMSs (FCSEMSs) and uncovered SEMSs (UCSEMSs).

Methods

We retrospectively analyzed consecutive patients with DMBO who received a SEMS. TRBO was determined using the Kaplan–Meier analysis, and complications were compared between the FCSEMS and UCSEMS groups. After TRBO‐associated factors were extracted using multivariate competing‐risks regression (CRR), propensity score‐adjusted CRRs were performed to verify their robustness.

Results

There were 180 patients (66 FCSEMSs and 114 UCSEMSs) enrolled in this study. There was no significant difference between median TRBO in the FCSEMS and UCSEMS groups (275 vs. 255 days, p = 0.67). Complications were more frequent in the FCSEMS than UCSEMS group (21.2% vs. 8.8%; p = 0.023). Multivariate CRR for TRBO‐associated factors revealed that “pancreatic ductal carcinoma (PDAC) treated with UCSEMS” was the only independent predictor of TRBO (p = 0.03). Similarly, the propensity score‐adjusted CRRs showed no significant difference in TRBO in “FCSEMS” vs “UCSEMS” (p = 0.96); however, there was a significant difference in “PDAC using UCSEMS” vs “other” (p = 0.043). In the palliative care group including any DMBO without chemotherapy, the first quartile of the TRBO of UCSEMS was 100 days.

Conclusions

UCSEMSs are a possible option for both patients with DMBO arising from PDAC and for patients with any DMBO receiving palliative care who should avoid SEMS‐related complications.

A Rare Case of Biliary Cryptococcosis Clinical Pharmacist Participation in Treatment and Pharmaceutical Care and Literature Review

Biliary cryptococcosis infection is extremely rare and difficult for preoperative diagnosis. We report a rare case of 61-year-old woman with biliary cryptococcal infection. To explore the general rule and case characteristics of biliary cryptococcal infection and provide a reference for future diagnosis and treatment, we consulted the PubMed database for reported biliary cryptococcal infection from 1985 to 2021. Including the present one, we collected 12 reports, among which half were male and five were younger than 18 years old. Clinical manifestations were mainly jaundice, while in vitro examination revealed bile duct dilatation and bile duct stenosis. In 8 cases (66.67%), symptoms improved or healed after antifungal treatment. Although preoperative misdiagnosis of cryptococcal infection is high, the antifungal treatment is quite effective. Thus, early accurate diagnosis can effectively improve the cure rate of biliary cryptococcosis infected patients.

Prolonged patency of fully covered self-expandable metal stents with an externally anchored plastic stent in distal malignant biliary obstruction

BACKGROUND : Fully covered self-expandable metal stents (FCSEMSs) are widely used for endoscopic treatment of distal malignant biliary obstruction (dMBO). We aimed to assess the efficacy of anchoring an external plastic stent to an FCSEMS in dMBO. METHODS : A multicenter retrospective cohort study was performed in patients with dMBO to compare stent patency between FCSEMSs and FCSEMSs with an externally anchored plastic stent (EPS). For external anchoring, a 7-Fr double-pigtail plastic stent (DPPS) was placed first in the bile duct, then an FCSEMS was deployed side-by-side. RESULTS : Among a total of 185 patients, 65 had an FCSEMS alone and 120 had an FCSEMS with an EPS. The median stent patency was significantly longer in the FCSEMS with an EPS group than in the FCSEMS only group (342 vs. 240 days; P = 0.04). The rate of stent migration was significantly lower in the FCSEMS with an EPS group than in the FCSEMS only group (10.8 % vs. 27.7 %; P = 0.01). There were no significant differences in the rates of stent occlusion and adverse events between the two groups. CONCLUSIONS : A novel and simple technique of anchoring an external plastic stent may decrease the risk of FCSEMS migration and prolong stent patency, without significantly increasing the adverse events rate in dMBO.

Complications of biliary stenting versus T-tube insertion after common bile duct exploration: A systematic review and meta-analysis

BACKGROUND

Complications following the insertion T-tube or stent after common bile duct exploration (CBDE) remain problematic in nowadays surgical era. Based on our knowledge, we did not find any meta-analysis intentionally evaluating the complications between both groups. At this moment, we aimed to analyze and compare both procedures' complications, efficacy, efficiency, and feasibility.

METHODS

We searched literature from four databases (EuroPMC, PubMed, Scopus, and ClinicalTrials.gov) up to June 2022 to compile the randomized controlled trials and pro-/retrospective cohort studies. Review Manager 5.4 was used to statistically analyze each outcome measured between biliary stenting and T-tube insertion.

RESULTS

Sixteen studies with 1,080 patients (534 biliary stents and 546 T-tube) were included for qualitative and quantitative analysis. The pooled risk ratio (RR) of the overall postoperative complications rate was significantly lower in the biliary stent group compared to the T-tube group 0.43 [95% confidence interval (CI) 0.23-0.80, p = 0.007]. In terms of the operation time, length of hospital stay, and readmission rate was also decreased in stenting as biliary drainage over T-tube placement 1.02 minutes [95% CI -1.53, -0.52, p < 0.0001], 1.96 days [95% CI -2.63, -1.29, p < 0.00001], and RR 0.39 [95% CI 0.15-0.97, p = 0.04], respectively.

CONCLUSIONS

Stenting as biliary drainage after CBDE was superior to T-tube insertion. A shorter operation time and hospital stay in biliary drainage resulted in a lower overall postoperative complication rate. Other influences, including the complexity and shorter learning curve, might also affect the superiority of biliary stenting.

Esophageal Dilation in Children: A State of the Art Review

Esophageal dilations in children are performed by several pediatric and adult professionals. We aim to summarize improvements in safety and new technology used for the treatment of complex and refractory strictures, including triamcinolone injection, endoscopic electro-incisional therapy, topical mitomycin-C application, stent placement, functional lumen imaging probe assisted dilation, and endoscopic vacuum-assisted closure in the pediatric population.

Do We Need to Use a Stent in Biliary Reconstruction to Decrease the Incidence of Biliary Complications in Liver Transplantation? A Systematic Review and Meta-Analysis

BACKGROUND AND AIM

Biliary complications are a significant cause of morbidity post-transplantation, and the routine use of biliary stents in liver transplantation to reduce these complications remains controversial. This study aimed to compare the incidence of biliary complications with and without the use of trans anastomotic biliary stent in liver transplantation.

METHOD

PubMed, Scopes, Web of Science, and Cochrane library were searched for eligible studies from inception to February 2022, and a systematic review and meta-analysis were done to compare the incidence of biliary complications in the two groups.

RESULTS

Seventeen studies with a total of 2623 patients were included. The pooled results from the included studies showed an equal rate of biliary complications (i.e., strictures, leaks and cholangitis) in stented and non-stented patients after liver transplantation. However, the cost and biliary intervention rates are higher in stented patients. In addition to that, our sub-group analysis showed no significant decrease in the incidence of biliary complications after using trans anastomotic biliary stent in living donor liver transplant (LDLT), deceased donor liver transplant (DDLT), Roux-en-Y hepaticojejunostomy (RYHJ), and duct-to-duct anastomosis, pediatric, and adult liver transplantation.

CONCLUSION

No added benefit on the routine use of endobiliary stent in liver transplantation. However, stented patients are at higher risk of needing multiple ERCPs.

Role of ERCP in Benign Biliary Strictures

Benign biliary strictures (BBS) can be associated with several causes, with postoperative and inflammatory strictures representing the most common ones. Endoscopy represents nowadays the first-line treatment in the management of BBS. Endoscopic balloon dilatation, plastic stents placement, fully covered metal stent placement, and magnetic compression anastomosis are the endoscopic techniques available for the treatment of BBS. The aim of this study is to perform a review of the literature to assess the role of endoscopy in the management of BBS and to evaluate the application of the different procedures in the different clinical settings.

Safety and Efficacy of a Large-Bore Biliary Metallic Stent for Malignant Biliary Obstruction

Self-expandable metallic stents (SEMSs) are typically inserted in patients with unresectable malignant biliary obstruction. However, SEMSs are susceptible to occlusion. To overcome this issue, we developed a large-bore, dumbbell-shaped, fully covered SEMS (FCSEMS-L) and compared its efficacy and safety with those of a conventional FCSEMS (FCSEMS-C) in patients with malignant biliary obstruction. Methods: Patients with unresectable distal malignant biliary obstruction were retrospectively enrolled between January 2011 and February 2021. All patients underwent endoscopic insertion of FCSEMSs. Recurrent biliary obstruction (RBO), patient survival time, complications, and prognosis were analyzed. Results: RBO occurred in 31 patients (35.6%) who received an FCSEMS-L, and in 34 (45.9%) who received an FCSEMS-C. Stent occlusion occurred in 19 patients (21.8%) who received an FCSEMS-L, and in 22 (29.7%) who received an FCSEMS-C. Stent migration occurred in 12 patients (13.8%) with an FCSEMS-L and 12 (16.2%) with an FCSEMS-C. The median time to RBO (TRBO) was 301 days with an FCSEMS-L and 203 days with an FCSEMS-C. The median survival time was 479 days with an FCSEMS-L and 523 days with an FCSEMS-C. The TRBO and patient survival time did not significantly differ between the two groups. Conclusions: There were no significant differences in efficacy and complication rates between the fully covered large bore SEMSs and conventional fully covered SEMSs.

Endoscopic Management of Pancreatobiliary Malignancies

Pancreatobiliary malignancies have poor prognosis, and many patients are inoperable at the time of diagnosis. When surgical resection is impossible, systemic chemotherapy or radiotherapy is traditionally conducted with trial of immunotherapy or gene therapy lately. With the rapid development of endoscopic instruments and accessories in recent years, not only endoscopic early detection, characterization, and staging but also endoscopic palliative management of the pancreatobiliary malignancies is expanding the horizons. Endoscopic management is often preferred due to similar efficacy to surgical management with less morbidity. Here, we review the methodology and treatment outcome of various endoscopic management strategies in pancreatobiliary malignancies including endoscopic complication management, local palliative therapy, endoscopy-assisted therapy, and pain control utilizing endoscopic retrograde cholangiopancreatography or endoscopic ultrasound.

Post-cholecystectomy Mirizzi Syndrome

Post-cholecystectomy Mirizzi syndrome (PCMS) is characterized by symptoms of recurrent abdominal pain, jaundice, and fever in patients who underwent cholecystectomy. Imaging is crucial in the diagnosis of PCMS and Mirizzi syndrome. Imaging modalities have evolved over the years with abdominal ultrasonography, computed tomography of the abdomen, and magnetic resonance cholangiopancreatography being used in the diagnosis of PCMS and Mirizzi syndrome. The imaging findings show obstruction of the common hepatic duct due to impingement by a stone in the cystic duct or gallbladder infundibulum. PCMS management has evolved over the years with the current first-line management being endoscopic intervention. This case describes a 61-year-old male presenting with recurrent right upper quadrant pain two years after undergoing cholecystectomy due to cholelithiasis. The patient was later diagnosed with PCMS, and endoscopic management was performed with complete resolution of the symptoms.

Palliation in Gallbladder Cancer: The Role of Gastrointestinal Endoscopy

Gallbladder cancer is a rare malignancy burdened by poor prognosis with an estimated 5-year survival of 5% to 13% due to late presentation, early infiltration of surrounding tissues, and lack of successful treatments. The only curative approach is surgery; however, more than 50% of cases are unresectable at the time of diagnosis. Endoscopy represents, together with surgery and chemotherapy, an available palliative option in advanced gallbladder cancers not eligible for curative treatments. Cholangitis, jaundice, gastric outlet obstruction, and pain are common complications of advanced gallbladder cancer that may need endoscopic management in order to improve the overall survival and the patients’ quality of life. Endoscopic biliary drainage is frequently performed to manage cholangitis and jaundice. ERCP is generally the preferred technique allowing the placement of a plastic stent or a self-expandable metal stent depending on the singular clinical case. EUS-guided biliary drainage is an available alternative for patients not amenable to ERCP drainage (e.g., altered anatomy). Gastric outlet obstruction is another rare complication of gallbladder malignancy growing in contact with the duodenal wall and causing its compression. Endoscopy is a less invasive alternative to surgery, offering different options such as an intraluminal self-expandable metal stent or EUS-guided gastroenteroanastomosis. Abdominal pain associated with cancer progression is generally managed with medical treatments; however, for incoercible pain, EUS-guided celiac plexus neurolysis has been described as an effective and safe treatment. Locoregional treatments, such as radiofrequency ablation (RFA), photodynamic therapy (PDT), and intraluminal brachytherapy (IBT), have been described in the control of disease progression; however, their role in daily clinical practice has not been established yet. The aim of this study is to perform a review of the literature in order to assess the role of endoscopy and the available techniques in the palliative therapy of advanced gallbladder malignancy.

Characterization and preliminary in vivo evaluation of a self-expandable hydrogel stent with anisotropic swelling behavior and endoscopic deliverability for use in biliary drainage

We demonstrate the potential of a novel self-expandable biliary stent comprised of poly(vinyl alcohol) (PVA) hydrogel with anisotropic swelling behavior and endoscopic deliverability in vivo, using a porcine stent model. The mechanism underlying the anisotropic swelling behavior and endoscopic deliverability (i.e., flexibility) was investigated by scanning electron microscopy (SEM), small-angle X-ray scattering (SAXS), evaluation of the water content and swelling ratio, and three-point bending tests. The in vivo experiment using a porcine stent model indicated that the tube-shaped PVA hydrogel could effectively expand the biliary tract, without disturbing bile flow. SEM and SAXS showed that PVA hydrogels prepared by drying under extension showed structural orientation along the extension axis, leading to anisotropic swelling. The water content of the PVA hydrogel was found to be crucial for maintaining flexibility as well as endoscopic deliverability. In conclusion, this study demonstrated the novel concept of using a hydrogel stent as a self-expandable biliary stent.

Superiority of Self-Expandable Metallic Stents Over Plastic Stents in Treatment of Malignant Distal Biliary Strictures

BACKGROUND & AIMS

Treatment of malignant biliary strictures with endoscopic retrograde cholangiopancreatography (ERCP) guided stent placement is highly effective. Our objective was to compare the efficacy and adverse outcomes between plastic stents (PS) and self-expandable metallic stents (SEMS).

METHODS

A cohort study was performed of all consecutive patients who underwent ERCP with stent placement for the management of malignant biliary stricture. Comparisons on clinical success, patency duration, stent dysfunction, unplanned reintervention and adverse outcomes were performed. Univariate and multivariable analyses were performed to identify factors associated with clinical success, need for reintervention, and stent dysfunction.

RESULTS

From 2012 to 2019, 1139 patients underwent ERCP with PS placement while 1008 patients received SEMS for the management of malignant biliary stricture. In distal strictures, SEMS reported a significantly higher rate of clinical success compared with PS (94.1% vs 87.4%, P < 0.001) and a lower rate of unplanned reintervention (17.1% vs 27.4%, P < 0.001). In hilar strictures, the rates of clinical success and unplanned intervention were comparable. The patency duration and time to unplanned reintervention were significantly longer with SEMS than PS, irrespective of stricture location. In distal stricture, PS was associated with a significantly higher rate of cholangitis than SEMS (6.9% vs 2.4%; P < .001) but a lower rate of pancreatitis (3.6% vs 6%; P = 0.021).

CONCLUSION

Given superior efficacy, durability and lower rates of cholangitis, SEMS should be offered as the first line endoscopic treatment option for malignant distal biliary stricture. For malignant hilar stricture, SEMS is an attractive alternative to PS in some cases by offering a comparable efficacy with a superior durability.

Prevention of pancreatitis after stent implantation for distal malignant biliary strictures: systematic review and meta-analysis

INTRODUCTION

Biliary stent placement remains a palliative treatment for patients with unresectable distal malignant biliary strictures (DMBS). The incidence of post-ERCP-pancreatitis (PEP) significantly increases in patients receiving fully covered self-expandable metal stents (FCSEMS) who undergo endoscopic retrograde cholangiopancreatography (ERCP).

AREAS COVERED

This review provides an overview of prevention of PEP after stent implantation for DMBSs. The following operational variables were evaluated: (1) stent type (plastic or metal stent); (2) stent location (above or across the sphincter of Oddi); (3) prophylactic pancreatic duct stent placement; (4) endoscopic sphincterotomy (EST). PubMed, EMBASE, and Cochrane database were searched to identify eligible studies up to October 2021. The odds ratio (OR) with 95% confidence intervals (CI) were pooled using fixed- or random- effects models.

EXPERT OPINION

1. PEP occurs more frequently in DMBS patients with self-expandable metal stents (SEMS) compared to that plastic stent (PS). 2. The PEP incidence is higher in covered stents than that in uncovered self-expandable metal stents (USEMS), but not significantly. 3. PEP incidence increases in patients receiving transpapillary FCSEMS placement, particularly when there is an absence of pancreatic duct dilation, and prophylactic pancreatic stenting is recommended for these patients. 4. Limited studies with small sample indicate that there is no significant difference in PEP incidence between transpapillary and suprapapillary stents placement for DMBS. 5. Limited studies indicate that EST does not significantly affect the incidence of pancreatitis in DMBS patients.

Emerging Trends in Biliary Stents: A Materials and Manufacturing Perspective

Biliary stent technology has come a long way since its inception. There have been significant advancements in materials used, designs, and deployment strategies. Options have expanded from thermoplastic and metallic...

Fully covered metal biliary stents: A review of the literature

Fully covered self-expandable metal stents (FCSEMS) represent the latest advancement of metal biliary stents used to endoscopically treat a variety of obstructive biliary pathology. A large stent diameter and synthetic covering over the tubular mesh prolong stent patency and reduce risk for tissue hyperplasia and tumor ingrowth. Additionally, FCSEMS can be easily removed. All these features address issues faced by plastic and uncovered metal stents. The purpose of this paper is to comprehensively review the application of FCSEMS in benign and malignant biliary strictures, biliary leak, and post-sphincterotomy bleeding.

Evaluation of post-ERCP pancreatitis after biliary stenting with self-expandable metal stents vs. plastic stents in benign and malignant obstructions

Background and study aims  There are conflicting data regarding the risk of post-ERCP pancreatitis (PEP) with self-expandable metallic stents (SEMS) compared to polyethylene stents (PS) in malignant biliary obstructions and limited data related to benign obstructions. Patients and methods  A retrospective cohort study was performed of 1136 patients who underwent ERCP for biliary obstruction and received SEMS or PS at a tertiary-care medical center between January 2011 and October 2016. We evaluated the association between stent type (SEMS vs PS) and PEP in malignant and benign biliary obstructions. Results  Among the 1136 patients included in our study, 399 had SEMS placed and 737 had PS placed. Patients with PS were more likely to have pancreatic duct cannulation, pancreatic duct stent placement, double guidewire technique, sphincterotomy and sphincteroplasty as compared to the SEMS group. On multivariate analysis, PEP rates were higher in the SEMS group (8.0 %) versus the PS group (4.8 %) (OR 2.27 [CI, 1.22, 4.24]) for all obstructions. For malignant obstructions, PEP rates were 7.8 % and 6.6 % for SEMS and plastic stents, respectively (OR 1.54 [CI, 0.72, 3.30]). For benign obstructions the PEP rate was higher in the SEMS group (8.8 %) compared to the PS group (4.2 %) (OR 3.67 [CI, 1.50, 8.97]). No significant differences between PEP severity were identified based on stent type when stratified based on benign and malignant. Conclusions  PEP rates were higher when SEMS were used for benign obstruction as compared to PS. For malignant obstruction, no difference was identified in PEP rates with use of SEMS vs PS.

Efficacy of an internal anchoring plastic stent to prevent migration of a fully covered metal stent in malignant distal biliary strictures: a randomized controlled study

BACKGROUND

Two types of self-expandable metal stents (SEMS) are available for malignant distal biliary obstruction: fully covered SEMS (FCSEMS) and uncovered SEMS. FCSEMS can prevent stent ingrowth, but a major concern is spontaneous migration. This study aimed to determine whether the additional insertion of a double-pigtail plastic stent to anchor the FCSEMS can prevent migration.

METHODS

68 patients with unresectable, malignant, distal, biliary obstruction were included in this multicenter, randomized, superiority trial. The patients were randomly assigned to receive either the FCSEMS plus an anchoring plastic stent (n = 33) or an FCSEMS alone (n = 35). After placement of the FCSEMS, the anchoring stent was inserted inside the FCSEMS. The primary outcome was the rate of stent migration during the 6-month follow-up. The secondary outcomes were stent-related adverse events, stent patency, and survival rates.

RESULTS

The baseline characteristics were similar between the two groups. The rate of stent migration at 6 months was significantly lower in patients with the FCSEMS plus anchoring stent (15 % vs. 40 %; P = 0.02). The mean stent patency was significantly longer in the FCSEMS plus anchoring group (237 days [95 % confidence interval [CI] 199 to 275] vs. 173 days [95 %CI 130 to 217]; P = 0.048). There were no significant differences in stent-related adverse events and overall survival rates at 6 months between the two groups.

CONCLUSIONS

Our data suggest that the additional double-pigtail plastic stent anchored the FCSEMS to prevent migration and prolonged patency without any serious adverse events.

Proximal Migration of Pancreatic Duct Stent in Pancreas Divisum: Challenges in Retrieval and Review of the Literature

Pancreas divisum is the most common congenital malformation of the pancreas. Sometimes it is considered an etiology when patients present with recurrent episodes of pancreatitis. Endoscopic retrograde pancreatography (ERP) with selective cannulation of the minor papilla with sphincterotomy and stent placement are performed in these patients. Proximal migration of pancreatic stents in pancreas divisum is rare and challenging to manage. We describe a case of proximal migration of a pancreatic stent in a patient with pancreas divisum and perform a review of literature.

Newer Stents for Unresectable Malignant Distal Biliary Obstruction: Striving for Perfection!

Endoscopic biliary stenting is one of the most commonly used palliative procedure in patients with unresectable malignant distal biliary obstruction. Biliary stenting can be performed with either plastic or metallic stents. Stent occlusion and migration are important limitations of currently available stents. Variety of newer stents with varying designs and stent materials like stents with antimigratory properties, antireflux stents, drug-eluting stents, radioactive stents, and bioabsorbable stents are being developed to overcome the limitations of currently available stents. In this article, we are discussing two articles on the newer stent designs (plastic and metal stents) for biliary drainage in patients with unresectable malignant distal biliary obstruction.

Comparing the 14-mm uncovered and 10-mm covered metal stents in patients with distal biliary obstruction caused by unresectable pancreatic cancer: a multicenter retrospective study

BACKGROUND

Endoscopic biliary drainage using metal stent (MSs) is an established palliative treatment for patients with unresectable malignant distal biliary obstruction (MDBO). However, a major drawback of MS is recurrent biliary obstruction (RBO). Uncovered MSs with a diameter of 14 mm (UMS-14) were developed to overcome this. We aimed to compare the clinical outcomes of UMS-14 with those of conventional covered MSs having a diameter of 10 mm (CMS-10).

METHODS

Consecutive patients with MDBO caused by unresectable pancreatic cancer, who underwent UMS-14 or CMS-10 placement at two tertiary-care centers, were retrospectively examined according to the Tokyo Criteria 2014.

RESULTS

Two hundred and thirty-eight patients who underwent UMS-14 (the UMS-14 group, n = 80) or CMS-10 (the CMS-10 group, n = 158) over a 62-month period were included. The technical and clinical success rates were similar between the two groups. RBO occurred in 20 (25%) and 59 (37%) patients of the UMS-14 and CMS-10 groups, respectively (p = 0.06). Median time till RBO was significantly longer in the UMS-14 group than in the CMS-10 group (not reached vs. 290 days, p = 0.04). Multivariate analysis revealed that CMS-10 placement was an independent risk factor for RBO (hazard ratio: 1.66, 95% confidence interval: 1.00-2.76). The incidence of early complications, including pancreatitis, and the overall survival (UMS-14 vs. CMS-10: 169 vs. 167 days, p = 0.83) were comparable between the two groups.

CONCLUSIONS

UMS-14 stents were safe and effective for treating patients with MDBO secondary to unresectable pancreatic cancer. The insertion of UMS-14 is recommended, because it is less likely to get occluded as compared to CMS-10.

Personalized Endoscopy in Complex Malignant Hilar Biliary Strictures

Malignant hilar biliary obstruction (HBO) represents a complex clinical condition in terms of diagnosis, surgical and medical treatment, endoscopic approach, and palliation. The main etiology of malignant HBO is hilar cholangiocarcinoma that is considered an aggressive biliary tract's cancer and has still today a poor prognosis. Endoscopy plays a crucial role in malignant HBO from the diagnosis to the palliation. This technique allows the collection of cytological or histological samples, direct visualization of the suspect malignant tissue, and an echoendoscopic evaluation of the primary tumor and its locoregional staging. Because obstructive jaundice is the most common clinical presentation of malignant HBO, endoscopic biliary drainage, when indicated, is the preferred treatment over the percutaneous approach. Several endoscopic techniques are today available for both the diagnosis and the treatment of biliary obstruction. The choice among them can differ for each clinical scenario. In fact, a personalized endoscopic approach is mandatory in order to perform the proper procedure in the singular patient.

Cholecystitis after Placement of Covered Self-Expandable Metallic Stents in Patients with Distal Malignant Biliary Obstructions

Background/Aims

Cholecystitis can occur after the placement of covered self-expandable metallic stents for distal malignant biliary obstructions. We aimed to identify risk factors for cholecystitis following covered self-expandable metallic stent placement.

Methods

We investigated risk factors related to cholecystitis following covered self-expandable metallic stent placement in 118 patients with distal malignant biliary obstructions between January 1, 2015 and April 30, 2019. Endoscopic assessments and tumor invasion to the arteries feeding the gallbladder were determined by a pancreaticobiliary endoscopist and a radiologist, respectively.

Results

The median patient age was 72 years (men, 61.0%). The flow of the contrast agent into the gallbladder and tumor involvement in the orifice of the cystic duct were observed in 35 (29.7%) and 35 (29.7%) patients, respectively. During the observation period (median, 179 days), cholecystitis occurred in 18 (15.3%) patients. Multivariate analysis revealed the flow of the contrast agent into the gallbladder (p=0.023) and tumor involvement in the orifice of the cystic duct (p=0.005) as significant independent risk factors associated with cholecystitis.

Conclusions

The flow of the contrast agent into the gallbladder and tumor involvement in the orifice of the cystic duct are potential independent risk factors for cholecystitis following the placement of covered self-expandable metallic stents. A follow-up prospective study is warranted to validate their influence.

Endoscopic devices and techniques for the management of bariatric surgical adverse events (with videos)

BACKGROUND AND AIMS

As the prevalence of obesity continues to rise, increasing numbers of patients undergo bariatric surgery. Management of adverse events of bariatric surgery may be challenging and often requires a multidisciplinary approach. Endoscopic intervention is often the first line of therapy for management of these adverse events. This document reviews technologies and techniques used for endoscopic management of adverse events of bariatric surgery, organized by surgery type.

METHODS

The MEDLINE database was searched through May 2018 for articles related to endoscopic management of adverse events of bariatric interventions by using relevant keywords such as adverse events related to "gastric bypass," "sleeve gastrectomy," "laparoscopic adjustable banding," and "vertical banded sleeve gastroplasty," in addition to "endoscopic treatment" and "endoscopic management," among others. Available data regarding efficacy, safety, and financial considerations are summarized.

RESULTS

Common adverse events of bariatric surgery include anastomotic ulcers, luminal stenoses, fistulae/leaks, and inadequate initial weight loss or weight regain. Devices used for endoscopic management of bariatric surgical adverse events include balloon dilators (hydrostatic, pneumatic), mechanical closure devices (clips, endoscopic suturing system, endoscopic plication platform), luminal stents (covered esophageal stents, lumen-apposing metal stents, plastic stents), and thermal therapy (argon plasma coagulation, needle-knives), among others. Available data, composed mainly of case series and retrospective cohort studies, support the primary role of endoscopic management. Multiple procedures and techniques are often required to achieve clinical success, and existing management algorithms are evolving.

CONCLUSIONS

Endoscopy is a less invasive alternative for management of adverse events of bariatric surgery and for revisional procedures. Endoscopic procedures are frequently performed in the context of multidisciplinary management with bariatric surgeons and interventional radiologists. Treatment algorithms and standards of practice for endoscopic management will continue to be refined as new dedicated technology and data emerge.

Best period to replace or change plastic stents with self-expandable metallic stents using multivariate competing risk regression analysis

In endoscopic biliary drainage (EBD) for various benign and malignant biliary disorders, the appropriate timing to replace or change a plastic stent (PS) with a self-expandable metallic stent (SEMS) remains unclear. This study aimed to define the best period to replace or change a PS with a SEMS. Between January 1, 2012, and December 31, 2018, 1,887 consecutive EBD procedures, including 170 SEMS placements, were retrospectively identified. The period to recurrent biliary obstruction (PRBO) was estimated and compared between the malignant and benign groups and according to each disease using time to event analysis and competing risk analysis. Compared with the benign group, the malignant group had significantly shorter median PRBO with interquartile range (IQR) after PS placement [108 (39 – 270) vs. 613 (191 – 1,329) days, P < 0.001], even on multivariate analysis, with a subdistribution hazard ratio (SHR) of 3.58 (P < 0.001). The shortest PRBO distribution from the first quartile of the non-RBO period was seen in Mirizzi syndrome cases (25 days, P = 0.030, SHR = 3.32) in the benign group and in cases of pancreatic cancer (32 days, P = 0.041, SHR = 2.06); perihilar bile duct cancer (27 days, P = 0.006, SHR = 2.69); and ampullary cancer (22 days, P = 0.001, SHR = 3.78) in the malignant group. Our study supports that stent replacement for the benign group is feasible after 6 months, and the best period to replace or change a PS with a SEMS should be decided on the basis of the underlying disease to prevent RBO.

A newly designed uncovered biliary stent for palliation of malignant obstruction: results of a prospective study

Background

Biliary decompression can reduce symptoms and improve quality of life in patients with malignant biliary obstruction. Endoscopically placed stents have become the standard of care for biliary drainage with the aim of improving hepatic function, relieving jaundice, and reducing adverse effects of obstruction. The purpose of this study was to evaluate the performance characteristics of a newly-designed, uncovered metal biliary stent for the palliation of malignant biliary obstruction.

Methods

This post-market, prospective study included patients with biliary obstruction due to a malignant neoplasm treated with a single-type, commercially available uncovered self-expanding metal stent (SEMS). Stents were placed as clinically indicated for palliation of jaundice and to potentially facilitate neo-adjuvant chemotherapy. The main outcome measure was freedom from recurrent biliary obstruction (within the stent) requiring re-intervention within 1, 3, and 6 months of stent insertion. Secondary outcome measures included device-related adverse events and technical success of stent deployment.

Results

SEMS were placed in 113 patients (73 men; mean age, 69); a single stent was inserted in 106 patients, and 2 stents were placed in 7 patients. Forty-eight patients survived and/or completed the 6 month study protocol. Freedom from symptomatic recurrent biliary obstruction requiring re-intervention was achieved in 108 of 113 patients (95.6, 95%CI = 90.0–98.6%) at study exit for each patient. Per interval analysis yielded the absence of recurrent biliary obstruction in 99.0% of patients at 1 month (n = 99; 95%CI = 97.0–100%), 96.6% of patients at 3 months (n = 77; 95%CI = 92.7–100%), and 93.3% of patients at 6 months (n = 48; 95%CI = 86.8–99.9%). In total, only 5 patients (4.4%) were considered failures of the primary endpoint. Most of these failures (4/5) were due to stent occlusion from tumor ingrowth or overgrowth. Overall technical success rate of stent deployment was 99.2%. There were 2 cases of stent-related adverse events (1.8%). There were no cases of post-procedure stent migration, stent-related perforation, or stent-related deaths.

Conclusions

This newly designed and marketed biliary SEMS system appears to be effective at relieving biliary obstruction and preventing re-intervention within 6 months of insertion in the overwhelming majority of patients. The device has an excellent safety profile, and associated high technical success rate during deployment.

Trial registration

The study was registered on clinicaltrials.gov on 14 October 2013 and the study registration number is NCT01962168. University of Massachusetts Medical School did not participate in the study.

[Mechanisms and prevention of biliary stent occlusion]

One of significant achievements of modern endoscopy is development of retrograde biliary stenting for obstructive jaundice. This method ensured widespread application of endoscopic decompression in the treatment of patients with malignant biliary obstruction as preparation before radical surgery and final palliative care. Endoscopic retrograde transpapillary stenting firmly took its place together with antegrade and percutaneous stenting. There are certain advantages of this technique including minimally invasiveness and favorable quality of life. However, this approach is associated with some drawbacks associated with stent occlusion and difficult correction of this complication. The maximum diameter of the plastic stent (PS) is determined by the width of the working channel of the duodenoscope. In this regard, self-expandable metal stents (SEMS) were developed to increase the diameter of bile drainage channel. SEMS are associated with prolonged function. However, there is another problem. It is a germination of SEMS followed by impossible removal of the stent for its subsequent replacement. A further step in development of endoscopic biliary stents was the use of special SEMS coating to exclude tumor or granulation ingrowth. The problem of biliary stent occlusion remains relevant despite some improvement of stenting results. Mechanisms of occlusion of biliary stents and prevention of these events are discussed in this review.

Management of Post-Transplant Anastomotic Stricture Using Self-Expandable Metal Stent

Anastomotic stricture (AS) is one of the complications of liver transplantation (LT) and can occur in up to 40% of living-donor LTs. Endoscopic management has become the first-line treatment of AS, and multiple plastic stents insertion has been mainly used in the past. Recently, many treatments utilizing fully covered self-expandable metal stents (cSEMSs) have been attempted, and results showing adequate treatment outcome have been reported. In this review, we look into the treatment performance and cautionary steps needed when using cSEMS as a treatment for AS.

Risk factors for distal migration of biliary plastic stents and related duodenal injury

BACKGROUND

The risk factors of duodenal injury from distal migrated biliary plastic stents remain uncertain. The aim of this study was to determine the risk factors of distal migration and its related duodenal injury in patients who underwent placement of a single biliary plastic stent for biliary strictures.

METHODS

We retrospectively reviewed all patients with biliary strictures who underwent endoscopic placement of a single biliary plastic stent from January 2006 to October 2017.

RESULTS

Two hundred forty-eight patients with 402 endoscopic retrograde cholangiopancreatography procedures were included. The incidence of distal migration was 6.2%. The frequency of duodenal injury was 2.2% in all cases and 36% in cases with distal migration. Benign biliary strictures (BBS), length of the stent above the proximal end of the stricture (> 2 cm), and duration of stent retention (< 3 months) were independently associated with distal migration (p = 0.018, p = 0.009, and p = 0.016, respectively). Duodenal injury occurred more commonly in cases with larger angle (≥ 30°) between the distal end of the stent and the centerline of the patient's body (p = 0.018) or in cases with stent retention < 3 months (p = 0.031).

CONCLUSIONS

The risk factors of distal migration are BBS and the length of the stent above the proximal end of the stricture. The risk factor of duodenal injury due to distal migration is large angle (≥ 30°) between the distal end of the stent and the centerline of the patient's body. Distal migration and related duodenal injury are more likely to present during the early period after biliary stenting.

Biliary spontaneous dislodgement spiral stent for patients who underwent mechanical lithotripsy

BACKGROUND

The incidence of post-endoscopic retrograde cholangiopancreatography (ERCP) cholangitis (PEC) in patients who underwent mechanical lithotripsy (ML) for large stone removal is high (up to 13.3%). One of the main causes is remaining small fragments or sludge that can impair normal biliary drainage. Endoscopic placement of a nasobiliary tube or a conventional plastic biliary stent has been commonly used under such conditions, but the patient may suffer from significant discomfort after the placement of a nasobiliary tube, while additional endoscopy is required for stent removal. We developed a biliary spontaneous dislodgement spiral stent (BSDSS) to overcome those shortcomings.

AIM

To evaluate the feasibility, safety, and effectiveness of inserting a BSDSS for patients who underwent ML for large stone removal.

METHODS

We conducted a single-center, retrospective, cohort study at West China Hospital, Sichuan University. A total of 91 consecutive patients with large biliary stones (≥ 10 mm) in the common bile duct who underwent ML between November 2017 and July 2018 were included. The 49 eligible patients were divided into the BSDSS group and the nasobiliary tube group. Technical success, post-ERCP adverse events (including PEC, post-ERCP pancreatitis, stone recurrence, BSDSS retention, self-extraction and dislocation of the nasobiliary tube), drainage time, and postoperative stay were measured and compared.

RESULTS

Twenty-one patients in the BSDSS group and 28 patients in the nasobiliary tube group were included in the analyses. The baseline characteristics and clinical information were similar in the two groups. Insertions of BSDSS and nasobiliary tube were technically successful in all 49 patients. There was no significant difference in the incidence of overall post-ERCP adverse events between the two groups (4.8% in the BSDSS group vs 17.9% in the nasobiliary tube group, P = 0.219). The median duration of drainage time (3 d in the BSDSS group vs 4 d in the nasobiliary tube group) and length of postoperative stay (4 d in the BSDSS group vs 5 d in the nasobiliary tube group) also did not differ (P = 0.934, and P = 0.223, respectively).

CONCLUSION

Endoscopic placement of a BSDSS appears to be feasible, safe and effective for patients who underwent ML for large stone removal.

Self-Expandable Metallic Stent Is More Cost Efficient Than Plastic Stent in Treating Anastomotic Biliary Stricture

BACKGROUND

Anastomotic bile duct stricture (ABS) is one of the most common complications after liver transplantation. Current practice of endoscopic retrograde cholangiopancreatography (ERCP) with multiple plastic stent (MPS) insertion often requires multiple sessions before achieving stricture resolution. We aimed to compare the efficacy of fully covered self-expandable metallic stent (FCSEMS) with MPS method while simultaneously analyzing the relative healthcare cost between the two methods in the management of ABS.

METHODS

Liver transplant patients with ABS who received ERCP with stent placement were identified by query of our endoscopic database. Comparative analyses between the group of patients treated with ERCP with MPS and the group treated with FCSEMS were performed. The costs to achieve stricture resolution, and the rates of stricture resolution, recurrence and complications were also compared.

RESULTS

A total of 158 patients underwent ERCP with stent insertion for the management of ABS. Of those, 49 patient received FCSEMS for their ABS while 109 patients were treated with MPS only. Our cost analysis showed early utilization of FCSEMS can deliver up to 25% savings in the total procedure cost while providing comparable rates of stricture resolution. The rates of technical success, stricture recurrence and adverse outcomes, and stricture free durations were also comparable between the two groups.

CONCLUSION

While providing efficacy and safety rates comparable to ERCP-MPS, the incorporation of FCSEMS at early stage of ABS management could provide a substantial savings by reducing the number of ERCP session to achieve stricture resolution. Optimization of the timing and duration of FCSEMS indwelling time needs further validation.

Endoscopic Retrograde Cholangiopancreatography-Related Complications and Their Management Strategies: A "Scoping" Literature Review

Endoscopic retrograde cholangiopancreatography (ERCP) is a well-known procedure with both diagnostic and therapeutic utilities in managing pancreaticobiliary conditions. With the advancements of endoscopic techniques, ERCP has become a relatively safe and effective procedure. However, as ERCP is increasingly being utilized for different advanced techniques, newer complications have been noticed. Post-ERCP complications are known, and mostly include pancreatitis, infection, hemorrhage, and perforation. The risks of these complications vary depending on several factors, such as patient selection, endoscopist's skills, and the difficulties involved during the procedure. This review discusses post-ERCP complications and management strategies with new and evolving concepts.

Trends and risk factors for 30-day readmissions in patients with acute cholangitis: analysis from the national readmission database

INTRODUCTION

Acute cholangitis (AC) can be associated with significant mortality and high risk of readmissions, if not managed promptly. We used national readmission database (NRD) to identify trends and risk factors associated with 30-day readmissions in patients with AC.

METHODS

We conducted a retrospective cohort study of adult patients admitted with AC from 2010-2014 and Q1-Q3 of 2015 by extracting data from NRD. Initial admission with a primary diagnosis of acute cholangitis (ICD-9 code: 576.1) was considered as the index admission and any admission after index admission was considered a readmission regardless of the primary diagnosis. Multivariable regression analyses were performed to assess the association.

RESULTS

From 52,906 AC index admissions, overall 30-day readmission rate was 21.48% without significant differences in the readmission rates across the study period. There was significant increase in the overall hospital charges for readmissions, while a significant reduction in the death rate was observed during the first readmission. Recurrent cholangitis (14%), septicemia (6.4%), and mechanical complication of bile duct prosthesis (3%) were the most common reasons for readmissions. The risk of readmission was significantly higher in patients with pancreatic neoplasm (OR 1.6, 95% CI 1.4-1.8), those who underwent percutaneous biliary procedures (OR 1.4, 95% CI 1.2-1.6), and who had an acute respiratory failure (OR 1.2, 95% CI 1.0-1.15). Other factors contributing to increased risk of readmissions included patients with Charleston comorbidity index > 3, diabetes, and length of stay > 3 days. Readmission risk was significantly lower in patients who underwent ERCP (OR 0.80, 95% CI 0.73-0.88) or cholecystectomy (OR 0.54, 95% CI 0.43-0.69).

CONCLUSIONS

AC is associated with a high 30-day readmission rate of over 21%. Patients with malignant biliary obstruction, increased comorbidities, and those who undergo percutaneous drainage rather than ERCP seem to be at the highest risk.

Biomaterials in Gastroenterology: A Critical Overview

In spite of the large diversity of diagnostic and interventional devices associated with gastrointestinal endoscopic procedures, there is little information on the impact of the biomaterials (metals, polymers) contained in these devices upon body tissues and, indirectly, upon the treatment outcomes. Other biomaterials for gastroenterology, such as adhesives and certain hemostatic agents, have been investigated to a greater extent, but the information is fragmentary. Much of this situation is due to the paucity of details disclosed by the manufacturers of the devices. Moreover, for most of the applications in the gastrointestinal (GI) tract, there are no studies available on the biocompatibility of the device materials when in intimate contact with mucosae and other components of the GI tract. We have summarized the current situation with a focus on aspects of biomaterials and biocompatibility related to the device materials and other agents, with an emphasis on the GI endoscopic procedures. Procedures and devices used for the control of bleeding, for polypectomy, in bariatrics, and for stenting are discussed, particularly dwelling upon the biomaterial-related features of each application. There are indications that research is progressing steadily in this field, and the establishment of the subdiscipline of "gastroenterologic biomaterials" is not merely a remote projection. Upon the completion of this article, the gastroenterologist should be able to understand the nature of biomaterials and to achieve a suitable and beneficial perception of their significance in gastroenterology. Likewise, the biomaterialist should become aware of the specific tasks that the biomaterials must fulfil when placed within the GI tract, and regard such applications as both a challenge and an incentive for progressing the research in this field.

Biocompatible Polymer Materials with Antimicrobial Properties for Preparation of Stents

Biodegradable polymers are promising materials for use in medical applications such as stents. Their properties are comparable to commercially available resistant metal and polymeric stents, which have several major problems, such as stent migration and stent clogging due to microbial biofilm. Consequently, conventional stents have to be removed operatively from the patient's body, which presents a number of complications and can also endanger the patient's life. Biodegradable stents disintegrate into basic substances that decompose in the human body, and no surgery is required. This review focuses on the specific use of stents in the human body, the problems of microbial biofilm, and possibilities of preventing microbial growth by modifying polymers with antimicrobial agents.

Identification of research trends concerning application of stent implantation in the treatment of pancreatic diseases by quantitative and biclustering analysis: a bibliometric analysis

OBJECTIVES

In recent years, with the development of biological materials, the types and clinical applications of stents have been increasing in pancreatic diseases. However, relevant problems are also constantly emerging. Our purpose was to summarize current hotspots and explore potential topics in the fields of the application of stent implantation in the treatment of pancreatic diseases for future scientific research.

METHODS

Publications on the application of stents in pancreatic diseases were retrieved from PubMed without language limits. High-frequency Medical Subject Headings (MeSH) terms were identified through Bibliographic Item Co-Occurrence Matrix Builder (BICOMB). Biclustering analysis results were visualized utilizing the gCLUTO software. Finally, we plotted a strategic diagram.

RESULTS

A total of 4,087 relevant publications were obtained from PubMed until May 15th, 2018. Eighty-three high-frequency MeSH terms were identified. Biclustering analysis revealed that these high-frequency MeSH terms were classified into eight clusters. After calculating the density and concentricity of each cluster, strategy diagram was presented. The cluster 5 "complications such as pancreatitis associated with stent implantation" was located at the fourth quadrant with high centricity and low density.

CONCLUSIONS

In our study, we found eight topics concerning the application of stent implantation in the treatment of pancreatic diseases. How to reduce the incidence of postoperative complications and improve the prognosis of patients with pancreatic diseases by stent implantation could become potential hotspots in the future research.

Post-Cholecystectomy Mirizzi Syndrome: A Case Report and Review of the Literature

Patient: Female, 44

Final Diagnosis: Post-cholecystectomy Mirizzi syndrome

Symptoms: Abdominal pain • nausea • vomiting

Medication: Tramadol • hydromorphone • prochlorperazine

Clinical Procedure: US • MRCP • ERCP• choledochoscopy

Specialty: Gastroenterology and Hepatology

Partially Covered Versus Uncovered Self-Expandable Metal Stents: Coating Nor Diameter Affect Clinical Outcomes

INTRODUCTION

Jaundice is a common initial presentation of malignant biliary stricture. In patients with life expectancies that are greater than 3 months, self-expanding metal stents (SEMS) offer a larger diameter stent with longer patency and fewer complications compared to plastic stents. There have been conflicting results in the published literature as to efficacy and safety between the various SEMS types and diameters. We compared stent coating (PCSEMS vs USEMS) and diameter on clinical outcomes regarding management of malignant biliary obstruction.

METHODS

A retrospective cohort study was conducted using a database of consecutive patients who underwent an ERCP with biliary SEMS placement (only 8 and 10 mm) between 2009 and 2017.

RESULTS

In total, 278 patients who had SEMS at ERCP for malignant biliary obstruction were included (213 PCSEMS vs 65 USEMS). The groups were demographically evenly matched. Clinical success rates and patency duration were not statistically significant between PCSEMS and USEMS (98.1% vs 95.5%, P = 0.36, and 302.5 vs 225.5 days, P = 0.72, respectively). Adverse event rates were similar between both PCSEMS and USEMS with regard to overall adverse events. Stent diameter did not have an impact on overall clinical success (98.9% vs 95.3%, P = 0.11) or patency duration (239 days vs 336 days, P = 0.51).

CONCLUSIONS

Our comparison of PCSEMS versus USEMS and 8 mm versus 10 mm showed no difference in clinical efficacy or adverse events between the two SEMS coatings and diameter, illustrating that coating and size do not matter in regard to stent choice, despite prior suggestive data.

Risk Factors for the Development of Stent-Associated Cholangitis Following Endoscopic Biliary Stent Placement

BACKGROUND AND AIM

To elucidate the overall risk and risk factors for developing cholangitis following biliary stent placement by endoscopic retrograde cholangiopancreatography (ERCP) and to determine the clinical outcomes of these individuals.

METHODS

We performed a retrospective review of 796 patients who had undergone 1127 ERCPs with biliary stent placement between 2007 and 2015 at a single tertiary care center. There were 91 episodes of stent-associated cholangitis (SAC) during the study period. Data obtained through the medical records included ERCP indication, patient factors (biliary anatomy, demographics, and comorbidities), stent characteristics (material, length, and design), change in serum bilirubin, stent indwelling time, rates and etiologies of bacteremia, and the mortality rate.

RESULTS

Those with SAC were more likely to have an anatomic biliary stricture (13.1% vs. 2.3%, p < .0001), with hilar and multiple strictures having the highest risk (19.1% vs. 11.6%, p = .04). The ERCP indication of malignant biliary obstruction was associated with higher rates of SAC (15.6% vs. 3.4%, p = < .0001). Rates of SAC were higher in those who failed to normalize total bilirubin (16.9% vs. 7.8%, p = .0005), and these episodes occurred earlier compared to those who normalized total bilirubin (median 30.5 days vs. 140.5 days, p < .0001).

CONCLUSIONS

Patients at increased risk of SAC include those with an anatomic stricture, malignant biliary obstruction, and those who fail to normalize total bilirubin after biliary stent placement. Future protocols should be designed to reduce the risk of cholangitis in these populations.