Decoding spatiotemporal transcriptional dynamics and epithelial fibroblast crosstalk during gastroesophageal junction development through single cell analysis

The gastroesophageal squamocolumnar junction (GE-SCJ) is a critical tissue interface between the esophagus and stomach, with significant relevance in the pathophysiology of gastrointestinal diseases. Despite this, the molecular mechanisms underlying GE-SCJ development remain unclear. Using single-cell transcriptomics, organoids, and spatial analysis, we examine the cellular heterogeneity and spatiotemporal dynamics of GE-SCJ development from embryonic to adult mice. We identify distinct transcriptional states and signaling pathways in the epithelial and mesenchymal compartments of the esophagus and stomach during development. Fibroblast-epithelial interactions are mediated by various signaling pathways, including WNT, BMP, TGF-β, FGF, EGF, and PDGF. Our results suggest that fibroblasts predominantly send FGF and TGF-β signals to the epithelia, while epithelial cells mainly send PDGF and EGF signals to fibroblasts. We observe differences in the ligands and receptors involved in cell-cell communication between the esophagus and stomach. Our findings provide insights into the molecular mechanisms underlying GE-SCJ development and fibroblast-epithelial crosstalk involved, paving the way to elucidate mechanisms during adaptive metaplasia development and carcinogenesis.

Endoscopic Features of Post-COVID-19 Cholangiopathy and Its Management Using ERCP

INTRODUCTION

Despite growing awareness of post-coronavirus disease 2019 (COVID-19) cholangiopathy as one of the most serious long-term gastrointestinal consequences of COVID-19, the endoscopic features of this disease are still poorly characterized. This study aimed to more precisely define its endoscopic features and to outline the role of endoscopic retrograde cholangiopancreatography (ERCP) in the management of this entity.

METHODS

In this observational study, 46 patients with confirmed post-COVID-19 cholangiopathy were included.

RESULTS

Based on the endoscopic features observed in 141 ERCP procedures, post-COVID-19 cholangiopathy can be classified as a variant of secondary sclerosing cholangitis in critically ill patients. It appeared early in the course of intensive care treatment of patients with COVID-19 (cholestasis onset 4.5 days after intubation, median). This form of cholangiopathy was more destructive than stricturing in nature and caused irreversible damage to the bile ducts. A centripetal pattern of intrahepatic bile duct destruction, the phenomenon of vanishing bile ducts, the absence of extrahepatic involvement, and the presence of intraductal biliary casts (85% of patients) were typical cholangiographic features of post-COVID-19 cholangiopathy. This cholangiopathy was often complicated by small peribiliary liver abscesses with isolation of Enterococcus faecium and Candida spp. in bile culture. The prognosis was dismal, with a 1-year liver transplantation-free survival rate of 44%. In particular, patients with peribiliary liver abscesses or destruction of the central bile ducts tended to have a poor prognosis (n.s.). As shown by multivariate analysis, bilirubin levels (on intensive care unit day 25-36) negatively correlated with liver transplantation-free survival (hazard ratio 1.08, P < 0.001). Interventional endoscopy with cast removal had a positive effect on cholestasis parameters (gamma-glutamyl transpeptidase, alkaline phosphatase, and bilirubin); approximately 60% of all individual values decreased.

DISCUSSION

Gastrointestinal endoscopy makes an important contribution to the management of post-COVID-19 cholangiopathy. ERCP is not only of great diagnostic and prognostic value but also has therapeutic value and therefore remains indispensable.

Endoscopic and surgical treatment of necrotizing pancreatitis-a comparison of short- and long-term outcome

BACKGROUND

Acute necrotizing pancreatitis is still related to high morbidity and mortality rates. Minimal-invasive treatment options, such as endoscopic necrosectomy, may decrease peri-interventional morbidity and mortality. This study aims to compare the initial operative with endoscopic treatment on long-term parameters, such as endocrine and exocrine functionality, as well as mortality and recurrence rates.

METHODS

We included 114 patients, of whom 69 were treated with initial endoscopy and 45 by initial surgery. Both groups were further assessed for peri-interventional and long-term parameters.

RESULTS

In the post-interventional phase, patients in the group of initial surgical treatment (IST) showed significantly higher rates of renal insufficiency (p < 0.001) and dependency on invasive ventilation (p < 0.001). The in-house mortality was higher in the surgical group, with 22% vs. 10.1% in the group of patients following initial endoscopic treatment (IET; p = 0.077). In long-term follow-up, the overall mortality was 45% for IST and 31.3% for IET (p = 0.156). The overall in-hospital stay and intensive care unit (ICU) stay were significantly shorter after IET (p < 0.001). In long-term follow-up, the prevalence of endocrine insufficiency was 50% after IST and 61.7% after IET (p = 0.281). 57.1% of the patients following IST and 16.4% of the patients following IET had persistent exocrine insufficiency at that point (p =  < 0.001). 8.9% of the IET and 27.6% of the IST patients showed recurrence of acute pancreatitis (p = 0.023) in the long-term phase.

CONCLUSION

In our cohort, an endoscopic step-up approach led to a reduced in-hospital stay and peri-interventional morbidity. The endocrine function appeared comparable in both groups, whereas the exocrine insufficiency seemed to recover in the endoscopic group in the long-term phase. These findings advocate for a preference for endoscopic treatment of acute necrotizing pancreatitis whenever feasible.

Endoscopic ultrasound-guided ethanol ablation versus surgical resection of insulinomas

PURPOSE

Insulinoma is a rare tumor of the pancreas that can lead to hypoglycemia. To date, the standard therapy is surgical resection. After the first case report of successful endoscopic ultrasound-guided (EUS) ethanol injection 16 years ago, the need for establishing an alternative treatment method remains unchanged given the high morbidity rates of surgery and its unsuitability in some patients.

MATERIALS AND METHODS

Here, we provide retrospective data from 33 insulinoma patients that were treated at our center between 2010 and 2021. Of these, 9 patients were treated with EUS-guided ethanol injection and 24 underwent pancreatic surgery.

RESULTS

The ethanol group was older (ethanol: mean ± SE 67.8±11.2 years vs. surgery: 52.3±15.7, p=0.014) with a higher Charlson Comorbidity Index (3.0 (1.0;4.0) vs. 1.0 (0.0;2.0), p=0.008). The lowest glucose values were similar between groups before (ethanol: 2.09±0.17 mmol/l vs. surgery: 1.81±0.08, p=0.158) and after (4.95±0.74 vs. 5.41±0.28, p=0.581) the respective treatments. Complications occurred more frequently in the surgery group (11 % vs. 54 %, p=0.026). One patient after prior partial pancreatectomy died postoperatively. The hospitalization time was significantly shorter in the ethanol group (4.78±0.78 days vs. 19.88±4.07, p<0.001).

CONCLUSION

EUS-guided ethanol injection can be similarly effective for the treatment of hyperinsulinemic hypoglycemia compared with pancreatic surgery but seems to be associated with less severe complications. This implies the need for prospective randomized trials in insulinoma patients with a low risk for malignancy.

Hepatobiliary long-term consequences of COVID-19: dramatically increased rate of secondary sclerosing cholangitis in critically ill COVID-19 patients

BACKGROUND

Increasing evidence suggests that secondary sclerosing cholangitis (SSC), which can lead to cirrhosis or liver failure, may be a hepatobiliary long-term complication of COVID-19. The aim of this study was to estimate the frequency and outcome of this COVID-19 sequela and to identify possible risk factors.

METHODS

This observational study, conducted at University Hospital Charité Berlin and Unfallkrankenhaus Berlin, Germany, involved hospitalized patients with COVID-19 pneumonia, including 1082 ventilated COVID-19 patients. We compared COVID-19 patients who developed SSC with a COVID-19 control group by univariate and multivariate analyses.

RESULTS

SSC occurrence after COVID-19 was observed exclusively in critically ill patients with invasive ventilation, albeit with extreme clustering among them. One in every 43 invasively ventilated COVID-19 patients developed this complication. Risk factors preceding the development of secondary sclerosing cholangitis in critically ill COVID-19 patients (SSC-CIP) were signs of systemic reduced blood oxygen supply (e.g., low PaO2/FiO2, ischemic organ infarctions), multi-organ failure (high SOFA score) at admission, high fibrinogen levels and intravenous ketamine use. Multivariate analysis confirmed fibrinogen and increased plasma lactate dehydrogenase as independent risk factors associated with cholangiopathy onset. The 1-year transplant-free survival rate of COVID-19-associated SSC-CIP was 40%.

CONCLUSIONS

COVID-19 causes SSC-CIP in a substantial proportion of critically ill patients. SSC-CIP most likely develops due to severe tissue hypoxia and fibrinogen-associated circulatory disturbances. A significant increase of patients with SSC-CIP is to be expected in the post-COVID era.

Correction: Complication rates of direct puncture and pull-through techniques for percutaneous endoscopic gastrostomy: Results from a large multicenter cohort

[This corrects the article DOI: 10.1055/a-1924-3525.].

Complication rates of direct puncture and pull-through techniques for percutaneous endoscopic gastrostomy: Results from a large multicenter cohort

Background and study aims  Two different techniques for percutaneous endoscopic gastrostomy (PEG) have been developed: classical pull-through and direct puncture techniques. This study compared the complication rate for both techniques in a large retrospective patient cohort. Patients and methods  Clinical data from patients who received a PEG in four high-volume centers for endoscopy were included retrospectively between January 2016 and December 2018. Patient characteristics and complication rates were correlated in univariate and multivariate analyses. Results  Data from 1014 patients undergoing a PEG insertion by the pull-through technique were compared to 183 patients for whom the direct puncture technique was used. The direct puncture technique was associated with a 50 % reduction in minor and 85.7 % reduction in major complications when compared to the pull-through technique. Multivariate analysis of these data revealed an odds ratio of 0.067 (0.02-0.226; P  < 0.001) for major complications in the direct puncture group. Conclusions  Compared to the pull-through technique, the direct puncture technique resulted in a significant reduction in complications. Despite the retrospective design of this study, these results suggest that the direct puncture technique may be preferable to improve patient safety.

How to perform EUS-guided biliary drainage

EUS-guided biliary drainage (EUS-BD) has recently gained widespread acceptance as a minimally invasive alternative method for biliary drainage. Even in experienced endoscopy centers, ERCP may fail due to inaccessibility of the papillary region, altered anatomy (particularly postsurgical alterations), papillary obstruction, or neoplastic gastric outlet obstruction. Biliary cannulation fails at first attempt in 5%-10% of cases even in the absence of these factors. In such cases, alternative options for biliary drainage must be provided since biliary obstruction is responsible for poor quality of life and even reduced survival, particularly due to septic cholangitis. The standard of care in many centers remains percutaneous transhepatic biliary drainage (PTBD). However, despite the high technical success rate with experienced operators, the percutaneous approach is more invasive and associated with poor quality of life. PTBD may result in long-term external catheters for biliary drainage and carry the risk of serious adverse events (SAEs) in up to 10% of patients, including bile leaks, hemorrhage, and sepsis. PTBD following a failed ERCP also requires scheduling a second procedure, resulting in prolonged hospital stay and additional costs. EUS-BD may overcome many of these limitations and offer some distinct advantages in accessing the biliary tree. Current data suggest that EUS-BD is safe and effective when performed by experts, although SAEs have been also reported. Despite the high number of clinical reports and case series, high-quality comparative studies are still lacking. The purpose of this article is to report on the current status of this procedure and to discuss the tools and techniques for EUS-BD in different clinical scenarios.

OUP accepted manuscript

Background

Photochemical internalization (PCI) is a novel technology for light-induced enhancement of the local therapeutic effect of cancer drugs, utilizing a specially designed photosensitizing molecule (fimaporfin). The photosensitizing molecules are trapped in endosomes along with macromolecules or drugs. Photoactivation of fimaporfin disrupts the endosomal membranes so that drug molecules are released from endosomes inside cells and can reach their therapeutic target in the cell cytosol or nucleus. Compared with photodynamic therapy, the main cytotoxic effect with PCI is disruption of the endosomal membrane resulting in delivery of chemotherapy drug, and not to the photochemical reactions per se. In this study we investigated the effect of PCI with gemcitabine in patients with inoperable perihilar cholangiocarcinoma (CCA).

Methods

The in vitro cytotoxic effect of PCI with gemcitabine was studied on two CCA-derived cell lines. In a fimaporfin dose-escalation phase I clinical study, we administered PCI with gemcitabine in patients with perihilar CCA (n = 16) to establish a safe and tolerable fimaporfin dose and to get early signals of efficacy. The patients enrolled in the study had tumors in which the whole length of the tumor could be illuminated from the inside of the bile duct, using an optical fiber inserted via an endoscope (Fig. 1). Fimaporfin was administered intravenously at day 0; gemcitabine (i.v.) and intraluminal biliary endoscopic laser light application on day 4; followed by standard gemcitabine/cisplatin chemotherapy.

Results

Preclinical experiments showed that PCI enhanced the effect of gemcitabine. In patients with CCA, PCI with gemcitabine was well tolerated with no dose-limiting toxicities, and no unexpected safety signals. Disease control was achieved in 10 of 11 evaluable patients, with a clearly superior effect in the two highest dose groups. The objective response rate (ORR) was 42%, including two complete responses, while ORR at the highest dose was 60%. Progression-free survival at 6 months was 75%, and median overall survival (mOS) was 15.4 months, with 22.8 months at the highest fimaporfin dose.

Conclusion

Photochemical internalization with gemcitabine was found to be safe and resulted in encouraging response and survival rates in patients with unresectable perihilar CCA.

EUS-guided Transgastric Drainage to Manage a Postoperative Pancreatic Fistula After Distal Pancreatectomy and Splenectomy in Recurrent Ovarian Cancer: A Case Report

BACKGROUND/AIM

Postoperative pancreatic fistula after distal pancreatectomy represents the most frequent procedure-related complication; however, a standard treatment is currently not available.

CASE REPORT

We herein report a case of postoperative pancreatic fistula after distal pancreatectomy and splenectomy in a patient affected by a platinum-sensitive ovarian cancer recurrence. The 59-year-old patient developed a pancreatic fistula on postoperative day 4. An endoscopic transgastric double-pigtail drainage was placed on postoperative day 13. The patient was discharged after 5 days and referred to adjuvant medical treatment. A month later, computed tomography revealed complete resolution of the fistula, the drainage was removed, and the patient continued chemotherapy. She recovered uneventfully at a 3-month follow-up.

CONCLUSION

EUS-guided drainage is a viable option in the management of postoperative pancreatic fistula, which can lead to a rapid resolution of peripancreatic fluid collections and to initiation of adjuvant chemotherapy with the slightest delay in ovarian cancer patients.

PuraStat in gastrointestinal bleeding: results of a prospective multicentre observational pilot study

Background

A recently developed haemostatic peptide gel for endoscopic application has been introduced to improve the management of gastrointestinal bleeding. The aim of this pilot study was to evaluate the feasibility, safety, efficacy and indication profiles of PuraStat in a clinical setting.

Methods

In this prospective observational multicentre pilot study, patients with acute non-variceal gastrointestinal bleeding (upper and lower) were included. Primary and secondary application of PuraStat was evaluated. Haemoglobin, prothrombin time, platelets and transfusion behaviour were documented before and after haemostasis. The efficacy of PuraStat was assessed during the procedure, at 3 days and 1 week after application.

Results

111 patients with acute gastrointestinal bleeding were recruited into the study. 70 percent (78/111) of the patients had upper gastrointestinal bleeding and 30% (33/111) had lower gastrointestinal bleeding. After primary application of PuraStat, initial haemostatic success was achieved in 94% of patients (74/79, 95% CI 88–99%), and in 75% of the patients when used as a secondary haemostatic product, following failure of established techniques (24/32, 95% CI 59–91%). The therapeutic success rates (absence of rebleeding) after 3 and 7 days were 91% and 87% after primary use, and 87% and 81% in all study patients. Overall rebleeding rate at 30 day follow-up was 16% (18/111). In the 5 patients who finally required surgery (4.5%), PuraStat allowed temporary haemostasis and stabilisation.

Conclusions

PuraStat expanded the therapeutic toolbox available for an effective treatment of gastrointestinal bleeding sources. It could be safely applied and administered without complications as a primary or secondary therapy. PuraStat may additionally serve as a bridge to surgery in order to achieve temporary haemostasis in case of refractory severe bleeding, possibly playing a role in preventing immediate emergency surgery.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00464-021-08589-6.

De Novo Development of Distal Jejunal and Duodenal Adenomas After 41 Months of Teduglutide Treatment in a Patient With Short-Bowel Syndrome: A Case Report

The glucagon-like peptide-2 (GLP-2) analogue teduglutide is a medical treatment option for patients with short-bowel syndrome-associated chronic intestinal failure. Because studies in mice have shown that GLP-2 analogues may promote the growth of colonic neoplasms, surveillance colonoscopies before and during teduglutide therapy were recommended. The occurrence of small-intestinal neoplasms has not been reported so far, except for a recent report about de novo development of hamartomatous duodenal polyps. We report a case of de novo development of small-intestinal premalignant adenomatous polyps in both bulbar duodenum and distal jejunum in a patient treated with teduglutide for 41 months. Therefore, additional endoscopic surveillance of the upper gastrointestinal tract may be advised during teduglutide therapy for early detection and removal of potential small-bowel adenomas.

Growth of nanowire arrays from micron-feature templates

Here, we present a two-step annealing procedure to imprint nanofeatures on SiO₂ starting from metallic microfeatures. The first annealing transforms the microfeatures into gold nanoparticles and the second imprints these nanoparticles into the SiO₂ layer with nanometric control. The resulting nanohole arrays show a high ensemble uniformity. As a potential application, the nanohole mask is used as a selective mask for the Ga self-assisted growth of GaAs nanowires (NWs). Thus, for the first time, a successful implementation of nano-self-imprinting that links high-throughput microlithography with bottom-up NW growth is shown. The beneficial hole morphology of the SiO₂ mask promotes high Ga droplet contact angles with the silicon substrate and the formation of single droplets in the mask holes. This droplet predeposition configuration enables a high vertical yield of NWs. Thus, this article describes a new protocol to grow NW devices that combines simultaneously nanosized holes and parallel processing.

What should be known prior to performing EUS?

Direct referral of patients for EUS – instead of preprocedural consultation with the endosonographer – has become standard practice (like for other endoscopic procedures) as it is time- and cost-effective. To ensure appropriate indications and safe examinations, the endosonographer should carefully consider what information is needed before accepting the referral. This includes important clinical data regarding relevant comorbidities, the fitness of the patient to consent and undergo the procedure, and the anticoagulation status. In addition, relevant findings from other imaging methods to clarify the clinical question may be necessary. Appropriate knowledge and management of the patients’ anticoagulation and antiplatelet therapy, antibiotic prophylaxis, and sedation issues can avoid unnecessary delays and unsafe procedures. Insisting on optimal preparation, appropriate indications, and clear clinical referral questions will increase the quality of the outcomes of EUS. In this paper, important practical issues regarding EUS preparations are raised and discussed from different points of view.

What should be known prior to performing EUS exams? (Part II)

In “What should be known prior to performing EUS exams, Part I,” the authors discussed the need for clinical information and whether other imaging modalities are required before embarking EUS examinations. Herewith, we present part II which addresses some (technical) controversies how EUS is performed and discuss from different points of view providing the relevant evidence as available. (1) Does equipment design influence the complication rate? (2) Should we have a standardized screen orientation? (3) Radial EUS versus longitudinal (linear) EUS. (4) Should we search for incidental findings using EUS?

Endosonography-guided drainage of loculated malignant ascites using double-pigtail plastic stents

Background and study aims  Endoscopic ultrasound (EUS)-guided drainage is a well-established procedure for peripancreatic fluid collections (PFC) that develop in the context of acute pancreatitis or following pancreatic surgery. Malignant ascites can occur in a loculated form resembling PFC causing a variety of symptoms, with limited treatment options. There is a paucity of data about application of EUS-guided drainage for these kinds of fluid collections. So far, only one report exists describing clinical success in three cases, using fully-covered self-expanding metal stents (FCSEMS). FCSEMS, however, have possible drawbacks, particularly if they have to remain in place for an indeterminate period of time. Herein, we describe EUS-guided drainage of loculated malignant ascites using double-pigtail plastic stents in two patients severely symptomatic from esophagogastric obstruction symptoms. Technical and clinical success was achieved in both cases without clinically significant complications including one case, where ongoing symptom control could be observed after 6 months of follow-up.

Gastrointestinal Tract As Entry Route for Hantavirus Infection

Background: Hantaviruses are zoonotic agents that cause hemorrhagic fevers and are thought to be transmitted to humans by exposure to aerosolized excreta of infected rodents. Puumala virus (PUUV) is the predominant endemic hantavirus in Europe. A large proportion of PUUV-infected patients suffer from gastrointestinal symptoms of unclear origin. In this study we demonstrate that PUUV infection can occur via the alimentary tract. Methods: We investigated susceptibility of the human small intestinal epithelium for PUUV infection and analyzed the resistance of virions to gastric juice. As model for intestinal virus translocation we performed infection experiments with human intestinal Caco-2 monolayers. In animal experiments we infected Syrian hamsters with PUUV via the intragastric route and tested seroconversion and protective immunity against subsequent Andes virus challenge. Results: PUUV retained infectivity in gastric juice at pH >3. The virus invaded Caco-2 monolayers in association with endosomal antigen EEA1, followed by virus replication and loss of epithelial barrier function with basolateral virus occurrence. Cellular disturbance and depletion of the tight junction protein ZO-1 appeared after prolonged infection, leading to paracellular leakage (leak flux diarrhea). Moreover, animal experiments led to dose-dependent seroconversion and protection against lethal Andes virus challenge. Conclusions: We provide evidence that hantavirus can infect the organism via the alimentary tract and suggest a novel aspect of hantavirus infection and pathogenesis. Significance: Hantaviruses are zoonotic pathogens causing severe hemorrhagic fevers worldwide. They are transmitted to humans by small mammals. To date, these viruses were thought to infect exclusively through the airborne route by inhalation of aerosols from infectious animal droppings or by rodent bites. In our work we could show that the alimentary tract is an alternative path of infection for hantaviruses, meaning a new association of virus and disease. These findings have impact on current textbook knowledge and bring many implications for hantavirus epidemiology and outbreak prevention measures.

Photodynamic Therapy Plus Chemotherapy Compared with Photodynamic Therapy Alone in Hilar Nonresectable Cholangiocarcinoma

Background/Aims

Standard treatments are not available for hilar nonresectable cholangiocarcinoma (NCC). It is unknown whether combination therapy of photodynamic therapy (PDT) plus systemic chemotherapy is superior to PDT alone.

Methods

We retrospectively reviewed 68 patients with hilar NCC treated with either PDT plus chemotherapy (PTD-C) or PDT monotherapy (PDT-M). The primary endpoint was the mean overall survival rate. Secondary endpoints included the 1-year survival rate, risk of cholangitic complications, and outcomes, which were evaluated according to the chemotherapy protocol.

Results

More than 90% of the study population had advanced hilar NCC Bismuth type III or IV. In the PDT-M group (n=35), the mean survival time was 374 days compared with 520 days in the PDT-C group (n=33, p=0.021). The 1-year survival rate was significantly higher in the PDT-C group compared with the PDT-M group (88% vs 58%, p=0.001) with a significant reduction of mortality (hazard ratio, 0.20; 95% confidence interval, 0.07 to 0.58; p=0.003). Gemcitabine monotherapy resulted in a shorter survival time compared with the gemcitabine combination therapy (mean, 395 days vs 566 days; p=0.09). Cholangitic complications were observed at a similar frequency in the PDT-C and PDT-M groups.

Conclusions

Combining repeated PDT with a gemcitabine-based combination therapy might offer a significant survival benefit in patients with hilar NCC.

Flexible percutaneous endoscopic retroperitoneal necrosectomy as rescue therapy for pancreatic necroses beyond the reach of endoscopic ultrasonography: A case series

Minimally invasive or endoscopic transluminal drainage and necrosectomy are the standard of care for infected pancreatic fluid collections and necroses after pancreatitis. In an endoscopic treatment algorithm, necroses beyond the reach of safe endoscopic access are typically treated by percutaneous drainage. We aimed to evaluate percutaneous minimally invasive necrosectomy using a purely endoscopic technique in patients with extensive necrosis. In patients with necroses beyond safe transluminal reach, the percutaneous drainage canal was used for flexible endoscopic access and dilatation of the tract to 20 mm. Percutaneous endoscopic necrosectomy was carried out through this canal. We present a case series of 14 patients in whom between one and four necrosectomy (median two) sessions were done to remove solid necroses successfully in 13 out of 14 patients. There were no major complications apart from one patient with abdominal compartment syndrome secondary to delayed erosion of the splenic artery. Percutaneous flexible necrosectomy might evolve into an alternative to surgical minimally invasive necrosectomy in anatomical sites beyond transluminal endoscopic reach.

DNA Cytometry for Differentiation Between Low- and Medium-grade Dysplasia in Intraductal Papillary Mucinous Neoplasms

BACKGROUND/AIM

The indication for resection of cystic pancreatic lesions is usually performed by sectional imaging criteria, such as the Sendai criteria. The aim of this study was to analyze a possible correlation between DNA cytometry and Sendai criteria for the differentiation between low-grade intraductal papillary mucinous neoplasms (IPMN-A) and medium-grade dysplasia (IPMN-B).

MATERIALS AND METHODS

Histopathological analysis, DNA index and preoperative Sendai criteria were determined in 16 patients who underwent pancreatic resection for IPMN.

RESULTS

All patients with IPMN-B showed aneuploid histograms with DNA indices ≥1.3, whereas three out of four patients with IPMN-A had diploid DNA indices ≤1.3. All 11 patients with one or more high-risk stigmata and aneuploid histograms had IPMN-Bs, whereas both patients who were Sendai-negative and diploid in the DNA analysis had an IPMN-A.

CONCLUSION

DNA index may be an important diagnostic tool for the differentiation of different IPMN types beyond the traditional Sendai criteria.

Ultrasound imaging features of isolated pancreatic tuberculosis

Background and Objectives:

Isolated pancreatic tuberculosis (PTB) is extremely rare worldwide. The purpose of this multicenter retrospective study is to analyze imaging features of histologically confirmed isolated PTB in order to determine the diagnostic features of the new methods contrast enhanced ultrasound (CEUS), ultrasound elastography and contrast enhanced endoscopic ultrasound (CE-EUS).

Patients and Methods:

We report on a retrospective data collection of 12 cases of PTB confirmed by histology or cytology. All examinations were interpreted by two independent readers in consensus. CEUS, CE-EUS and ultrasound elastography were performed according to the European Federation of Societies for Ultrasound in Medicine and Biology guidelines.

Results:

In PTB patients the common bile duct was never dilated. Multiple retroperitoneal lymph nodes are the second important B-mode ultrasound feature detected in 75% of PTB patients. CE-EUS was performed in three PTB patients demonstrating hyperenhancement. On elastography, all PTB lesions were markedly stiffer than surrounding pancreatic parenchyma.

Conclusions:

Here we report the first time on CEUS and elastography features of PTB. PTB had some typical imaging features with iso- or hyperenhancement on CE(E) US. PTB is markedly stiffer on elastography. If clinicians are aware of clinical features of PTB and conduct appropriate investigations with multiple modalities including B-mode ultrasound, CEUS, and EUS guided fine needle aspiration, diagnosis of PTB without laparotomy is possible and the disease can be effectively treated with anti-tuberculous drugs.

Endoscopic endoluminal vacuum therapy is superior to other regimens in managing anastomotic leakage after esophagectomy: a comparative retrospective study

BACKGROUND

Anastomotic leakage after esophagectomy is a life-threatening complication. No comparative outcome analyses for the different treatment regimens are yet available.

METHODS

In a single-center study, data from all esophagectomy patients from January 1995 to January 2012, including tumor characteristics, surgical procedure, postoperative anastomotic leakage, leakage therapy regimens, APACHE II scores, and mortality, were collected, and predictors of patient survival after anastomotic leakage were analyzed.

RESULTS

Among 366 resected patients, 62 patients (16 %) developed an anastomotic leak, 16 (26 %) of whom died. Therapy regimens included surgical revision (n = 18), endoscopic endoluminal vacuum therapy (n = 17), endoscopic stent application (n = 12), and conservative management (n = 15). APACHE II score at the initiation of treatment for leakage was the strongest predictor of in-hospital mortality (p < 0.0017). Conservatively managed patients showed mild systemic illness (mean APACHE II score 5) and no mortality. In systemically ill patients matched for APACHE II scores (mean, 14.4), endoscopic endoluminal vacuum therapy patients had lower mortality (12 %) compared to surgically treated (50 %, p = 0.01) cases and patients managed by stent placement (83 %, p = 00014, log rank test). No other clinical or laboratory parameters significantly influenced patient survival.

CONCLUSIONS

Endoscopic endoluminal vacuum therapy was the best treatment of anastomotic leakage in systemically ill patients after esophagectomy in this retrospective analysis. It should therefore be considered an important instrument in the management of this disorder.

Prognostic relevance of gastric cancer staging by endoscopic ultrasound

BACKGROUND

Recent trials and guidelines have established the use of neoadjuvant chemotherapy for resectable UICC stage II to IV gastric cancers. In this setting, preoperative staging is pivotal for correct patient selection. This cohort study was designed to assess the accuracy of endoscopic ultrasound (EUS) and the ability to select correctly patients for neoadjuvant chemotherapy on the basis of survival outcome.

METHODS

Eighty-two consecutive Caucasian patients (46 male; median age 72 years) with gastric cancer underwent EUS staging and subsequent surgery without perioperative chemotherapy or radiotherapy. Patients were followed for a median of 800 days postoperatively. Pathology and EUS UICC and T stages were compared and evaluated as predictors of survival using Kaplan-Meier and Cox regression analysis.

RESULTS

The overall accuracy of EUS for UICC classification compared with pathology was 62 %, and the accuracy for delineation of UICC I was 89 %. For the therapeutically relevant differentiation of early gastric cancer (UICC stage I), EUS (mean survival, 2,298 days, R2 = 0.23) and pathology (2,461 days, R2 = 0.24) predicted survival equally well. Similar results were obtained for T staging by EUS (mean survival, 2,065 days for uT1/2, R2 = 0.24) or pathology (2,185 days, R2 = 0.22).

CONCLUSIONS

EUS identifies the low risk subgroup (uUICC stage I or uT1/2) with similar performance as pUICC stage I or stage pT1/2 in gastric cancer and very similar survival characteristics. EUS thus may be the noninvasive method of choice for preoperative selection of patients for immediate resection versus neoadjuvant chemotherapy.

Endoscopic ultrasound criteria to predict the need for intervention in pancreatic necrosis

Background

The natural course and treatment strategies for asymptomatic or oligosymptomatic pancreatic necrosis are still poorly defined. The aim of this retrospective study was to establish criteria for the need of intervention in patients with pancreatic necrosis.

Methods

A total of 31 consecutive patients (18 male, median age 58 yrs.) diagnosed with pancreatic necrosis by endoscopic ultrasound, in whom a decision for initial conservative treatment was made, were followed for the need of interventions such as endoscopic or surgical intervention, or death.

Results

After a median follow-up of 243 days, 21 patients remained well without intervention and in 10 patients an endpoint event occurred. In a multivariate logistic regression analysis of the clinical and endosonographic parameters, liquid content was the single independent predictor for intervention (p = 0.0006). The presence of high liquid content in the pancreatic necrosis resulted in a 64% predicted endpoint risk as compared to 2% for solid necrosis.

Conclusions

Pancreatic necrotic cavities with high liquid content are associated with a high risk of complications. Therefore, close clinical monitoring is needed and early elective intervention might be considered in these patients.

Endoscopic ultrasound-guided endoscopic necrosectomy of the pancreas: is irrigation necessary?

BACKGROUND

Findings have shown endoscopic necrosectomy to be beneficial for patients with symptomatic pancreatic necrosis accessible for an endoscopic approach. The available studies show that endoscopic necrosectomy requires a multitude of subsequent procedures including repeat irrigation for removal of the necrotic material. This study aimed to investigate the need for additional irrigation in patients with necrotizing pancreatitis treated by endoscopic necrosectomy.

METHODS

The study enrolled 35 consecutive patients (27 men) with a median age of 59 years who had pancreatic necrosis treated with endoscopic necrosectomy. Endoscopic ultrasound-guided internal drainage and consecutive endoscopic necrosectomy was combined with interval multistenting of the cavity. Neither endoscopic nor external irrigation was part of the procedure.

RESULTS

An average of 6.2 endoscopy sessions per patient were needed for access, necrosectomy, and stent management. The in-hospital mortality rate was 6% (2/35), including one procedure-related death resulting from postinterventional aspiration. The immediate morbidity rate was 9% (3/35). It was possible to achieve clinical remission for all the surviving patients with no additional surgery needed for management of the necroses. The median follow-up period was 23 months.

CONCLUSION

Neither endoscopic nor external flushing is needed for successful endoscopic treatment of symptomatic necroses. Even without irrigation, the outcome for patients treated with endoscopic necrosectomy is comparable to that described in the published data.

IL-1β and ADAM17 are central regulators of β-defensin expression in Candida esophagitis

Candida albicans resides on epithelial surfaces as part of the physiological microflora. However, under certain conditions, it may cause life-threatening infections, including Candida sepsis. We have recently shown that human β-defensins (hBDs) hBD-2 and hBD-3 are upregulated in Candida esophagitis and that this antifungal host response is distinctly regulated by NF-κB and MAPK/activator protein-1 (AP-1) pathways. Here, we show that C. albicans induces hBD-2 through an autocrine IL-1β loop and that activation of the epidermal growth factor receptor (EGFR) by endogenous transforming growth factor-α (TGF-α) is a crucial event in the induction of hBD-3. To further dissect upstream signaling events, we investigated expression of the central sheddases for EGFR ligands ADAM10 and ADAM17 in the healthy and infected esophagus. Next, we used pharmaceutical inhibitors and small-interfering RNA-mediated knock down of ADAM10 and ADAM17 to reveal that ADAM17-induced shedding of TGF-α is a crucial step in the induction of hBD-3 expression in response to Candida infection. In conclusion, we describe for the first time an autocrine IL-1β loop responsible for the induction of hBD-2 expression and an ADAM17-TGF-α-EGFR-MAPK/AP-1 pathway leading to hBD-3 upregulation in the course of a Candida infection of the esophagus.

Staging of rectal cancer by EUS: depth of infiltration in T3 cancers is important

BACKGROUND

EUS is an established method for staging of rectal cancer. Nevertheless, there are few data about the significance of infiltration depth measured by EUS.

OBJECTIVE

Assessment of accuracy of T and N staging by EUS with attention to infiltration depth as provided by EUS.

DESIGN

Part retrospective, part prospective study.

SETTING

Community and tertiary referral hospital, covering the period before neoadjuvant therapy for advanced rectal cancer was established.

PATIENTS

Eighty-three patients (60% men) with untreated rectal cancer.

INTERVENTION

EUS examination.

MAIN OUTCOME MEASUREMENTS

We examined the correlation between EUS findings and postoperative histology. T3 cancers as diagnosed by EUS were classified into minimally invasive (1-2 mm) or advanced (>2 mm) tumors depending on the depth of infiltration beyond the muscularis propria.

RESULTS

Accuracy of T staging and N status was 76% and 63%, respectively. Overstaging by EUS was more common in minimally invasive T3 by EUS (uT3) (8 of 16 [50%]) compared with advanced uT3 tumors (1 of 24 [4%]) (P=.01). Accuracy of EUS discrimination between T1/2 and T3/4 in rectal cancer for all but minimally invasive uT3 rectal tumors was 88%.

LIMITATIONS

Partly retrospective analysis.

CONCLUSIONS

EUS examination of rectal carcinoma determines T stage with high accuracy. Additionally, it provides information beyond T and N staging. The 50% probability of overstaging patients with minimally invasive uT3N0 by EUS may argue for managing these cancers as stage I disease, ie, to refer the patient for surgery without neoadjuvant therapy.

Transluminal endoscopic necrosectomy after acute pancreatitis: a multicentre study with long-term follow-up (the GEPARD Study)

BACKGROUND

As with endoscopic transmural drainage of peripancreatic fluid collections, the same transluminal access can be expanded to introduce an endoscope through the gastrointestinal wall into the retroperitoneum and remove infected pancreatic necroses under direct visual control. This study reports the first large series with long-term follow-up.

METHODS

Data for all patients undergoing transluminal endoscopic removal of (peri)pancreatic necroses between 1999 and 2005 in six different centres were collected retrospectively, and the patients were followed up prospectively until 2008. The initial patient and treatment outcome data were recorded, as were long-term results.

RESULTS

Ninety-three patients (63 men, 30 women; mean age 57 years) underwent a mean of six interventions starting at a mean of 43 days after an attack of severe acute pancreatitis. After establishment of transluminal access to the necrotic cavity and subsequent endoscopic necrosectomy, initial clinical success was obtained in 80% of the patients, with a 26% complication and a 7.5% mortality rate at 30 days. After a mean follow-up period of 43 months, 84% of the initially successfully treated patients had sustained clinical improvement, with 10% receiving further endoscopic and 4% receiving surgical treatment for recurrent cavities; 16% suffered recurrent pancreatitis.

CONCLUSIONS

Direct transluminal endoscopic removal of pancreatic necroses is associated with good long-term maintenance of the high initial efficacy; complications can occur, with an associated mortality of around 7.5%. Further studies are necessary in order to optimise endotherapy and define its role in relation to surgery in the clinical management of such patients.

[Role of endoscopic ultrasound (EUS) in the staging of rectal cancer]

Modern therapy of the rectal carcinoma is dependent on sophisticated preinterventional diagnostics, which is decisive with regard to the indication for neoadjuvant therapy and influences the decision concerning the method of surgery. Endoscopic ultrasound is an established part of this diagnostic process. It is characterised by a high accuracy in T and N staging. New therapeutic concepts and the rapid development of competing methods make a new assessment of its value necessary.

EUS-guided alcohol ablation of an insulinoma

BACKGROUND

Surgical resection is currently considered to be the criterion standard for treatment of insulinomas. Alternative treatments, despite medication with diazoxide, are lacking. EUS-guided ethanol ablation of endocrine tumors has not been reported before.

INTERVENTION

A 78-year-old woman was referred with typical symptoms of an insulinoma. Diagnosis was confirmed by laboratory findings, EUS, and EUS-guided FNA. Because of severe complications during several hypoglycemic episodes, a poor general condition, and strict refusal of surgical resection, the decision was made to ablate the insulinoma by EUS-guided alcohol injection. A total of 8 mL 95% ethanol was injected into the tumor.

RESULTS

The patient was discharged and exhibited no further hypoglycemic episodes, and her general condition improved rapidly. Based on clinical, morphologic, and biochemical criteria, we achieved a durable complete remission of the tumor.

CONCLUSIONS

EUS-guided ablation may become a minimally invasive alternative for patients with insulinomas in whom surgery is not feasible.

Cloning, expression and purification of recombinant streptokinase: partial characterization of the protein expressed in Escherichia coli

We cloned the streptokinase (STK) gene of Streptococcus equisimilis in an expression vector of Escherichia coli to overexpress the profibrinolytic protein under the control of a tac promoter. Almost all the recombinant STK was exported to the periplasmic space and recovered after gentle lysozyme digestion of induced cells. The periplasmic fraction was chromatographed on DEAE Sepharose followed by chromatography on phenyl-agarose. Active proteins eluted between 4.5 and 0% ammonium sulfate, when a linear gradient was applied. Three major STK derivatives of 47.5 kDa, 45 kDa and 32 kDa were detected by Western blot analysis with a polyclonal antibody. The 32-kDa protein formed a complex with human plasminogen but did not exhibit Glu-plasminogen activator activity, as revealed by a zymographic assay, whereas the 45-kDa protein showed a K(m) = 0.70 microM and kcat = 0.82 s-1, when assayed with a chromogen-coupled substrate. These results suggest that these proteins are putative fragments of STK, possibly derived from partial degradation during the export pathway or the purification steps. The 47.5-kDa band corresponded to the native STK, as revealed by peptide sequencing.

Clinical aspects of acute myeloid leukemias of the FAB types M3 and M4Eo. The AML Cooperative Group

Acute promyelocytic leukemia (AML FAB M3, APL) and acute myelomonocytic leukemia with abnormal eosinophils (AML M4Eo) are considered distinct entities with characteristic clinical, morphological, cytogenetic, and prognostic features. Promyelocytic leukemia is characterized by abnormal promyelocytes replacing normal hematopoiesis associated with a translocation between the long arms of chromosomes 15 and 17 t (15; 17), severe coagulopathy, and responsiveness to all-trans retinoic acid (tretinoin). Characteristic features of AML M4Eo are a myelomonocytic marrow infiltration, eosinophils with abnormal immature granules positive for chloroacetate esterase, an inversion or translocation of chromosome 16, and an increased risk of meningeal relapses. Prognosis of both types of AML has been reported to be better than prognosis of the other entities combined. Since most of the published data were collected from heterogeneous patient populations treated with various chemotherapeutic regimens, we have analyzed treatment outcome of AML M3 and M4Eo in the AMLCG-85 study for patients younger than 60 years. For the total population of 594 patients of this study, CR rate was 68.89%, early death rate 11.60%, and no or partial remission was achieved in 19.51% of the cases. Of 40 patients with AML M3 or M3 v complete remission was attained in 62.5%. Nine patients died within 42 days after the start of antileukemic therapy (22.5%). Of these nine, four died because of infection, five because of bleeding. Relapse-free survival rate was 59% after 3 years, significantly better than the respective curve of the other FAB types combined (35% after 3 years). In AML M4Eo, 91.7% of the 24 patients reached complete remission. The early death rate was 8.3%. No case of nonresponse was seen. Relapse-free survival rate was 49% after 3 years compared with 35% for the other types combined.