Asian consensus statements on endoscopic management of walled-off necrosis. Part 2: Endoscopic management

Comorbidity burden and outcomes of endoscopic ultrasound-guided treatment of pancreatic fluid collections: Multicenter study with nationwide data-based validation

OBJECTIVES

The appropriate holistic management is mandatory for successful endoscopic ultrasound (EUS)-guided treatment of pancreatic fluid collections (PFCs). However, comorbidity status has not been fully examined in relation to clinical outcomes of this treatment.

METHODS

Using a multi-institutional cohort of 406 patients receiving EUS-guided treatment of PFCs in 2010-2020, we examined the associations of Charlson Comorbidity Index (CCI) with in-hospital mortality and other clinical outcomes. Multivariable logistic regression analysis was conducted with adjustment for potential confounders. The findings were validated using a Japanese nationwide inpatient database including 4053 patients treated at 486 hospitals in 2010-2020.

RESULTS

In the clinical multi-institutional cohort, CCI was positively associated with the risk of in-hospital mortality (Ptrend < 0.001). Compared to patients with CCI = 0, patients with CCI of 1-2, 3-5, and ≥6 had adjusted odds ratios (95% confidence intervals) of 0.76 (0.22-2.54), 5.39 (1.74-16.7), and 8.77 (2.36-32.6), respectively. In the nationwide validation cohort, a similar positive association was observed; the corresponding odds ratios (95% confidence interval) were 1.21 (0.90-1.64), 1.52 (0.92-2.49), and 4.84 (2.63-8.88), respectively (Ptrend < 0.001). The association of higher CCI with longer length of stay was observed in the nationwide cohort (Ptrend < 0.001), but not in the clinical cohort (Ptrend = 0.18). CCI was not associated with the risk of procedure-related adverse events.

CONCLUSIONS

Higher levels of CCI were associated with a higher risk of in-hospital mortality among patients receiving EUS-guided treatment of PFCs, suggesting the potential of CCI in stratifying the periprocedural mortality risk.

TRIAL REGISTRATION

The research based on the clinical data from the WONDERFULcohort was registered with UMIN-CTR (registration number UMIN000044130).

WONDER-02: plastic stent vs. lumen-apposing metal stent for endoscopic ultrasound-guided drainage of pancreatic pseudocysts-study protocol for a multicentre randomised non-inferiority trial

BACKGROUND

Endoscopic ultrasound (EUS)-guided transluminal drainage has become a first-line treatment modality for symptomatic pancreatic pseudocysts. Despite the increasing popularity of lumen-apposing metal stents (LAMSs), plastic stents may resolve non-necrotic fluid collections effectively with lower costs and no LAMS-specific adverse events. To date, there has been a paucity of data on the appropriate stent type in this setting. This trial aims to assess the non-inferiority of plastic stents to a LAMS for the initial EUS-guided drainage of pseudocysts.

METHODS

The WONDER-02 trial is a multicentre, open-label, non-inferiority, randomised controlled trial, which will enrol pancreatic pseudocyst patients requiring EUS-guided treatment in 26 centres in Japan. This trial plans to enrol 80 patients who will be randomised at a 1:1 ratio to receive either plastic stents or a LAMS (40 patients per arm). In the plastic stent group, EUS-guided drainage will be performed using two 7-Fr double pigtail stents. In the LAMS group, the treatment will be performed in the same way except for LAMS use. The step-up treatment will be performed via endoscopic and/or percutaneous procedures at the trial investigator's discretion. The primary endpoint is clinical success, which is defined as a decrease in a pseudocyst size to ≤ 2 cm and an improvement in inflammatory indicators (i.e. body temperature, white blood cell count, and serum C-reactive protein). Secondary endpoints include technical success, adverse events including mortality, pseudocyst recurrence, and medical costs.

DISCUSSION

The WONDER-02 trial will investigate the efficacy and safety of plastic stents compared to a LAMS in EUS-guided treatment of symptomatic pancreatic pseudocysts with a particular focus on the non-inferior efficacy of plastic stents. The findings will help establish a new treatment algorithm for this population.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06133023 registered on 9 November 2023. UMIN000052647 registered on 30 October 2023. jRCT1032230444 registered on 7 November 2023.

Controversies in endoscopic ultrasonography-guided management of walled-off necrosis

Walled-off necrosis (WON) develops as local complications after acute necrotizing pancreatitis. Although less invasive interventions such as endoscopic ultrasonography (EUS)-guided drainage and endoscopic necrosectomy are selected over surgical interventions, delayed and step-up interventions are still preferred to avoid procedure-related adverse events. However, there is a controversy about the appropriate timing of drainage and subsequent necrosectomy. The advent of large-caliber lumen-apposing metal stents has also brought about potential advantages of proactive interventions, which still needs investigation in future trials. When step-up interventions of necrosectomy and additional drainage are necessary, a structured or protocoled approach for WON has been reported to improve safety and effectiveness of endoscopic and/or percutaneous treatment, but has not been standardized yet. Finally, long-term outcomes such as recurrence of WON, pancreatic endocrine, and exocrine function are increasingly investigated in association with disconnected pancreatic duct syndrome. In this review we discuss current evidence and controversy on EUS-guided management of WON.

Endoscopic ultrasound-guided pancreatic fluid collection drainage: Where are we?

Pancreatic fluid collections (PFCs) result from injury to the pancreas from acute or chronic pancreatitis, surgery, or trauma. Management of these collections has evolved over the last 2 decades. The choice of interventions includes percutaneous, endoscopic, minimally invasive surgery, or a combined approach. Endoscopic drainage is the drainage of PFCs by creating an artificial communication between the collection and gastrointestinal lumen that is maintained by placing a stent across the fistulous tract. In this editorial, we endeavored to update the current status of endoscopic ultrasound-guided drainage of PFCs.

Postponed endoscopic necrosectomy results in a lower rate of additional intervention for infected walled-off necrosis

Although endoscopic necrosectomy (EN) is more frequently used to manage walled-off necrosis (WON), there is still debate over how much time should pass between the initial stent placement and the first necrosectomy. This study aims to determine the effect of performing EN within different timings after placing the initial stent on clinical outcomes for WON. A retrospective study on infected WON patients compared an early necrosectomy within one week after the initial stent placement with a necrosectomy that was postponed after a week. The primary outcomes compared the rate of clinical success and the need for additional intervention after EN to achieve WON resolution. 77 patients were divided into early and postponed necrosectomy groups. The complete resolution of WON within six months of follow-up was attained in 73.7% and 74.3% of patients in both the early and postponed groups. The early group tended to a greater need for additional intervention after EN (26.8% early necrosectomy vs. 8.3% postponed necrosectomy, P = 0.036). Our study does not demonstrate that early necrosectomy is superior to postponed necrosectomy in terms of clinical success rate, total count of necrosectomy procedures, procedure-related complications, length of hospitalization and prognosis. Conversely, patients in the postponed group received fewer additional interventions.

Risk factors for adverse outcomes at various phases of endoscopic ultrasound-guided treatment of pancreatic fluid collections: Data from a multi-institutional consortium

OBJECTIVES

No comprehensive study has examined short- and long-term adverse outcomes of endoscopic ultrasound (EUS)-guided treatment of pancreatic fluid collections (PFCs) including walled-off necrosis (WON) and pseudocysts.

METHODS

In a multi-institutional cohort of 357 patients receiving EUS-guided treatment of PFCs (228 with WON and 129 with pseudocysts), we examined PFC type-specific risk factors for procedure-related adverse events (AEs), clinical failure, and recurrence. Odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs) were computed using the logistic and Cox regression models, respectively, adjusting for potential confounders.

RESULTS

Adverse events were observed predominantly in WON, and risk factors were WON extension to the pelvis (OR 2.49; 95% CI 1.00-6.19) and endoscopic necrosectomy (OR 5.15; 95% CI 1.61-16.5). Risk factors for clinical failure in WON treatment included higher Charlson Comorbidity Index (OR for ≥3 vs. ≤2, 2.58; 95% CI 1.05-6.35), extension to the pelvis (OR 3.63; 95% CI 1.57-8.43), nonuse of a lumen-apposing metal stent (OR 2.88; 95% CI 1.10-7.54), and percutaneous drainage (OR 3.73; 95% CI 1.27-10.9). Patients with pseudocysts extending to the paracolic gutter and the need for more than two endoscopic/percutaneous procedures had ORs for clinical failure of 5.28 (95% CI 1.10-25.3) and 5.52 (95% CI 1.61-18.9), respectively. Pseudocysts requiring the multigateway approach were associated with a high risk of recurrence (HR 4.00; 95% CI 1.11-11.6).

CONCLUSION

The adverse outcomes at various phases of EUS-guided PFC treatment may be predictable based on clinical parameters. Further research is warranted to optimize treatment strategies for high-risk patients.

Inverse association of hospital volume with in-hospital mortality rate of patients receiving EUS-guided interventions for pancreatic fluid collections

BACKGROUND AND AIMS

EUS-guided interventions currently serve as first-line treatment for symptomatic pancreatic fluid collections (PFCs) but require high-level expertise and multidisciplinary care. Hospital caseload has not been fully examined in relation to clinical outcomes of patients with endoscopically managed PFCs.

METHODS

Using the Diagnosis Procedure Combination database (a Japanese nationwide inpatient database), we identified 4053 patients receiving EUS-guided treatment of PFCs at 486 hospitals between 2010 and 2020 and examined an association of hospital volume (average annual number of cases at a hospital) with in-hospital mortality. Associations with bleeding, length of stay, and total costs were examined as secondary analyses. Multivariable logistic regression analysis was conducted with adjustment for potential confounders.

RESULTS

The hospital volume was inversely associated with the risk of in-hospital mortality (Ptrend < .001). The adjusted odds ratio for in-hospital mortality comparing the extreme quintiles of hospital volume was .17 (95% confidence interval, .09-.33). A restricted cubic spline analysis yielded no statistically significant evidence on the nonlinear relationship (Pnonlinearity = .19). The types of stents (plastic vs lumen-apposing metal stent) seemed to have no effect modification on the volume-mortality relationship (Pinteraction = .58). Higher hospital volume was also associated with lower risk of bleeding, shorter length of stay, and lower medical costs of inpatient care.

CONCLUSIONS

Higher hospital volume was associated with a lower risk of in-hospital mortality of patients receiving EUS-guided treatment of PFCs. A further investigation is warranted to justify the volume-based selective referral of the patients.

Time to think prime times for treatment of necrotizing pancreatitis: Pendulum conundrum

Pancreatic fluid collections (PFCs) typically develop as local complications of acute pancreatitis and complicate the clinical course of patients with acute pancreatitis and potentially fatal clinical outcomes. Interventions are required in cases of symptomatic walled-off necrosis (WON) (matured PFCs with necrosis) and pancreatic pseudocysts (matured PFCs without necrosis). In the management of necrotizing pancreatitis and WON, endoscopic ultrasound-guided transluminal drainage combined with on-demand endoscopic necrosectomy (i.e. the step-up approach) is increasingly used as a less invasive treatment modality compared with a surgical or percutaneous approach. Through the substantial research efforts and development of specific devices and stents (e.g. lumen-apposing metal stents), endoscopic techniques of PFC management have been standardized to some extent. However, there has been no consensus about timing of carrying out each treatment step; for instance, it is uncertain when direct endoscopic necrosectomy should be initiated and finished and when a plastic or metal stent should be removed following clinical treatment success. Despite emerging evidence for the effectiveness of noninterventional supportive treatment (e.g. antibiotics, nutritional support, irrigation of the cavity), there has been only limited data on the timing of starting and stopping the treatment. Large studies are required to optimize the timing of those treatment options and improve clinical outcomes of patients with PFCs. In this review, we summarize the current available evidence on the indications and timing of interventional and supportive treatment modalities for this patient population and discussed clinical unmet needs that should be addressed in future research.

Endoscopic treatment of pancreatic necrosis: Still searching for perfection!

Over last few years, there has been a paradigm shift in the management of infected pancreatic necrosis with endoscopic and minimally invasive "step-up" management approach replacing open surgical necrosectomy. Because of being associated with reduced occurrence of new onset multi-organ failure, external pancreatic fistulae, shorter hospital stay, lower costs, and better quality of life compared with minimally invasive surgical approach, endoscopic "step-up" management approach is the preferred intervention for endoscopically accessible pancreatic necrotic collections at expert centers with endoscopic expertise. Development of lumen apposing metal stents and improvised accessories for interventional endoscopic ultrasound has revolutionized the endoscopic management of pancreatic necrosis making it more effective and safer. Despite these promising developments, endoscopic transluminal necrosectomy (ETN) remains the Achilles heel. Lack of dedicated endoscopic accessories, poor endoscopic visualization within the necrotic cavity, limited diameter of the instrument channel of the endoscope that is a significant impediment to remove large amount of necrotic material, and uncertain ability to avoid vessels and vital structures in the necrotic cavity are important limitations during endoscopic necrosectomy. Recent devices and solutions including use of cap assisted necrosectomy, over the scope grasper and powered endoscopic debridement device are welcome steps in our pursuit for an ideal, safer, and efficacious ETN device. This review will discuss recent advances as well as challenges in the endoscopic management of pancreatic necrosis.

WONDER-01: immediate necrosectomy vs. drainage-oriented step-up approach after endoscopic ultrasound-guided drainage of walled-off necrosis-study protocol for a multicentre randomised controlled trial

BACKGROUND

With the increasing popularity of endoscopic ultrasound (EUS)-guided transmural interventions, walled-off necrosis (WON) of the pancreas is increasingly managed via non-surgical endoscopic interventions. However, there has been an ongoing debate over the appropriate treatment strategy following the initial EUS-guided drainage. Direct endoscopic necrosectomy (DEN) removes intracavity necrotic tissue, potentially facilitating early resolution of the WON, but may associate with a high rate of adverse events. Given the increasing safety of DEN, we hypothesised that immediate DEN following EUS-guided drainage of WON might shorten the time to WON resolution compared to the drainage-oriented step-up approach.

METHODS

The WONDER-01 trial is a multicentre, open-label, superiority, randomised controlled trial, which will enrol WON patients aged ≥ 18 years requiring EUS-guided treatment in 23 centres in Japan. This trial plans to enrol 70 patients who will be randomised at a 1:1 ratio to receive either the immediate DEN or drainage-oriented step-up approach (35 patients per arm). In the immediate DEN group, DEN will be initiated during (or within 72 h of) the EUS-guided drainage session. In the step-up approach group, drainage-based step-up treatment with on-demand DEN will be considered after 72-96 h observation. The primary endpoint is time to clinical success, which is defined as a decrease in a WON size to ≤ 3 cm and an improvement of inflammatory markers (i.e. body temperature, white blood cell count, and C-reactive protein). Secondary endpoints include technical success, adverse events including mortality, and recurrence of the WON.

DISCUSSION

The WONDER-01 trial will investigate the efficacy and safety of immediate DEN compared to the step-up approach for WON patients receiving EUS-guided treatment. The findings will help us to establish new treatment standards for patients with symptomatic WON.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05451901, registered on 11 July 2022. UMIN000048310, registered on 7 July 2022. jRCT1032220055, registered on 1 May 2022.

Endoscopic transluminal drainage and necrosectomy for infected necrotizing pancreatitis: Progress and challenges

Infected necrotizing pancreatitis (INP) represents a severe condition in patients with acute pancreatitis. Invasive interventions are recommended in symptomatic INP. Growing evidence has suggested interventional strategies of INP evolving from traditional surgery to minimally invasive step-up endoscopic procedures. However, there is still no standardized protocol for endoscopic interventions. Recently, various studies have been published about the endoscopic management of INP. This article reviews published articles and guidelines to present the progress and challenges of endoscopic transluminal drainage and necrosectomy in INP.

Efficacy and safety of endoscopic ultrasound guided drainage of pseudocysts and walled-off necrosis after failure of percutaneous drainage

BACKGROUND

Endoscopic Ultrasound (EUS) represents the gold standard for initial drainage of pancreatic fluid collections (PFC) due to various etiologies. However, data concerning salvage EUS drainage after initial percutaneous drainage are limited. The purpose of our study was to evaluate the clinical outcomes and safety of EUS-guided drainage of pancreatic collections after failure of percutaneous drainage.

METHODS

This retrospective study was conducted in a single, tertiary university center from August 2013 to January 2020. Indication was pancreatic collection after acute pancreatitis with PFC requiring EUS-guided drainage after failure of percutaneous drainage.

RESULTS

Twenty-two patients with PFC after acute pancreatitis were included (mean age 64.1 ± 11.3 years) of which 4/22 (18.2%) had pancreatic pseudocyst and 18/22 (81.8%) presented with a walled-off necrosis. Seventy-six interventions were performed among the 22 patients. Lumen-Apposing Metal Stent (LAMS) were used in 5/22 (22.7%) and double pigtail plastic stents in 17/22 (77.3%) of interventions with a median number intervention of 3 per patient (range 1 to 7). Technical success rate was 98.7% (75/76) with an overall clinical success of 81.8% (18/22). Procedure related adverse events rate was 9.1% (2/22) including one bleeding and one pancreatic fistula. Two non-procedure related deaths were observed.

CONCLUSION

EUS-guided pancreatic collection drainage is clinically effective and safe after clinical/technical failure of radiological percutaneous management.

Early versus delayed interventions for necrotizing pancreatitis: A systematic review and meta-analysis

Objectives

Interventions for necrotizing pancreatitis are generally postponed until 4 weeks after the onset of acute pancreatitis, but there remains controversy about whether we should always wait >4 weeks or can intervene early when necessary. This meta‐analysis was conducted to evaluate treatment outcomes of necrotizing pancreatitis according to the cut‐off defined in the revised Atlanta classification (≤4 vs. >4 weeks).

Methods

Using PubMed, Web of Science, and the Cochrane database, we identified clinical studies published until March 2022 with data comparing outcomes of early and delayed interventions of necrotizing pancreatitis. We pooled data on adverse events, mortality, technical and clinical success rates, and needs for necrosectomy and open surgery, using the random‐effects model.

Results

We identified 11 retrospective studies, including 775 patients with early interventions and 725 patients with delayed interventions. Patients with early interventions tended to be complicated by organ failure. The rate of adverse events was comparable (OR 1.41, 95% CI 0.66–3.01; p = 0.38) but the rate of mortality was significantly higher (OR 1.70, 95% CI 1.21–2.40; p < 0.01) in early interventions. Technical success rates were similarly high but clinical success rates tended to be low (OR 0.39, 95% CI 0.15–1.00; p = 0.05) in early interventions, though not statistically significant. Pooled ORs for necrosectomy and open surgery were 2.14 and 1.23, respectively.

Conclusions

Early interventions for necrotizing pancreatitis were associated with higher mortality rates and did not reduce adverse events or improve clinical success. However, our results should be confirmed in prospective studies.

Predicting success of direct endoscopic necrosectomy with lumen-apposing metal stents for pancreatic walled-off necrosis

BACKGROUND AND AIMS

Direct endoscopic necrosectomy (DEN) with lumen-apposing metal stents (LAMSs) is increasingly used in the management of pancreatic walled-off necrosis (WON). However, it still remains unknown which patients will fail to respond to DEN with LAMSs and require additional surgical intervention. Therefore, the aim of our study was to explore predictors of successful DEN with LAMSs for pancreatic WON.

METHODS

This is a retrospective analysis of a prospectively collected database. All consecutive patients who underwent DEN with LAMSs for pancreatic WON were included. Collected data were demographics, disease severity, morphologic features, and procedure characteristics. Potential factors affecting DEN outcome were predefined and analyzed.

RESULTS

One hundred one consecutive patients undergoing DEN with LAMSs for WON were identified, among whom 4 patients were excluded for technical failure (n = 1) and previous debridement without LAMSs (n = 3). In the 97 included patients, clinical success was achieved in 79 patients (81.4%). In logistic multivariable regression, 3 independent factors were negatively associated with success of DEN with LAMSs: increasing Acute Physiology and Chronic Health Evaluation II score (odds ratio [OR], .70; 95% confidence interval [CI], .55-.90; P = .005), >50% pancreatic necrosis (OR, .16; 95% CI, .03-.77; P = .022), and paracolic gutter extension (OR, .08; 95% CI, .02-.42; P = .003). A receiver-operating characteristic curve of the prediction model with these 3 factors demonstrated an area under the curve of .926.

CONCLUSIONS

Paracolic gutter extension, increasing Acute Physiology and Chronic Health Evaluation II score, and >50% gland necrosis are negative predictors for success of DEN with LAMSs in WON. This prediction model with nomogram may be helpful in clinical decision-making and prognostication.

Disconnected pancreatic duct syndrome and outcomes of endoscopic ultrasound-guided treatment of pancreatic fluid collections: Systematic review and meta-analysis

BACKGROUND

Disconnected pancreatic duct syndrome (DPDS) frequently occurs in patients with acute necrotizing pancreatitis and resultant pancreatic fluid collection (PFC). We performed a systematic review and meta-analysis to evaluate outcomes of endoscopic ultrasound-guided treatment of PFCs according to the presence of DPDS.

METHODS

Using PubMed, Embase, and the Cochrane database, we identified clinical studies published until January 2021 with data comparing outcomes of endoscopic ultrasound-guided drainage of PFCs between DPDS and non-DPDS patients. We pooled data on technical and clinical success rates, PFC recurrence, and adverse events using the random-effects model.

RESULTS

We identified five eligible articles including 941 PFC patients treated with endoscopic ultrasound-guided interventions. Clinical success, defined as resolution of the PFC and symptoms, was achieved in a majority of the cases irrespective of DPDS (pooled odds ratio [OR] comparing DPDS to non-DPDS patients, 0.77; 95% confidence interval [CI] 0.33-1.81). Compared to patients without DPDS, patients with DPDS were more likely to undergo PFC recurrence (pooled OR 6.72; 95% CI 2.72-16.6) after clinical resolution of PFC. Prolonged plastic stent placement following the clinical resolution was more frequently performed in DPDS patients than in non-DPDS patients (pooled OR 15.9; 95% CI 2.76-91.9). No statistically significant difference was observed between the groups in terms of the rate of technical success, adverse events, or mortality.

CONCLUSION

Disconnected pancreatic duct syndrome was associated with higher rate of PFC recurrence after successful endoscopic treatment of PFCs. Future studies should evaluate effectiveness and optimal duration of long-term placement of transmural plastic stents for PFCs with DPDS.

A Novel Strategy for Transmural Stent Removal in Necrotizing Pancreatitis Undergoing Endoscopic Transmural Necrosectomy

BACKGROUND

Although metal stents have been widely used in the endoscopic step-up approach for necrotizing pancreatitis, the exact timing of transmural stent removal has not been well studied. Here, we report a novel strategy for stent removal and compare it with the conventional strategy.

MATERIALS AND METHODS

This retrospective, nested, case-control study analyzed all adult necrotizing pancreatitis patients who underwent endoscopic transmural necrosectomy (ETN). Clinical outcomes were compared between case group (a novel strategy in which the stents were removed during the last necrosectomy when the ETN endpoint was achieved) and 1:1 necrosis extent matched control group (the conventional strategy).

RESULTS

Baseline characteristics was comparable between case group (n=37) and control group (n=37). Three (8.1%) patients in case group and 1 (2.7%) patient in control group needed additional ETN after stent removal (P>0.05). Nearly all patients (case: 97.3%; control: 94.6%) achieved clinical success. There was no difference in disease-related (case: 40.5%; control: 37.8%) or stent-related (case: 27.0%; control: 16.2%) complications. Case group had a trend of shorter length of stent placement (median: 20.0 vs. 29.5 d, P>0.05).

CONCLUSIONS

The novel strategy of transmural stent removal during last necrosectomy might be feasible which needed further validation. Compared with the convention strategy, the novel strategy avoids one endoscopy procedure and should be considered in clinical practice.

Early endoscopic treatment of symptomatic pancreatic necrotic collections

EUS-guided transmural endoscopic drainage is commonly used in the treatment of WOPN in the late phase of ANP. The role of endoscopic intervention remains unclear in the early phase of ANP. This study aimed to prospectively evaluate early endoscopic treatment of ANCs compared with endoscopic drainage of WOPN. Overall, 71 patients with ANP who underwent transmural endoscopic drainage for necrotic collections were included. Endoscopic intervention was performed within the first four weeks of ANP in 25 (35.21%) patients with ANC (Group 1) and in 46 (64.79%) patients after four weeks since the onset of ANP with WOPN (Group 2). The overall mean age of patients was 49.9 (22–79) years and 59 of them were males. The mean time of active drainage and duration of total endoscopic treatment was 26.8 and 16.9 days (P = 0.0001) and 270.8 and 164.2 days (P = 0.0001) in Groups 1 and 2, respectively. The average total number of endoscopic interventions was 9.5 and 4.5 in Groups 1 and 2, respectively (P = 0.0001). The clinical success rate, frequency of complications of endoscopic interventions, long-term success rate, and recurrence rate were not significantly different between the groups (P > 0.05 for each). Transmural endoscopic drainage is effective method of treatment of early ANCs within the first four weeks of ANP. However, compared with endoscopic intervention in WOPN, more interventions and longer duration of drainage are required.

Effectiveness and Safety of a Single 7-French Plastic Stent for Endoscopic Ultrasound-guided Pancreatic Pseudocyst Drainage and Long-term Follow-up Outcomes

Background

Endoscopic ultrasound (EUS)-guided cystogastrostomy with a single 7-French (Fr) double-pigtail stent (DPS) is less popular due to the concern of stent patency. We aimed to assess the effectiveness, complications, and long-term outcomes of a single 7-Fr DPS in the endoscopic drainage of uncomplicated pseudocysts, containing no or minimal (<10%) debris.

Methods

A retrospective review of patients with pancreatic pseudocysts, who underwent EUS-guided cystogastrostomy during 2010-2018, and a systematic review of the literature were conducted.

Results

Of 45 patients, 14 patients underwent endoscopic drainage of uncomplicated pseudocysts using a single 7-Fr × 5 cm DPS. The mean cyst size was 10.2 ± 3.5 cm. Stent placement had a 100% technical and clinical success, defined as complete resolution of symptoms and regression of the cyst size by more than 50% at 8 weeks after drainage. The median follow-up was 42.4 months (range, 10-103). The pseudocysts resolved without recurrence in 92.8%. Spontaneous stent dislodgment was noted in 70% at a mean follow-up of 18 months. Additional interventions were required in 14% of cases due to stent occlusion and migration. A systematic review of literature related to EUS-guided cystogastrostomy using single and multiple plastic stents included 9 of 333 studies (222 patients). The analysis showed the pooled clinical success of 89% (95% confidence interval [CI], 82.0-94.2) and complication rate of 13% (95% CI, 5.7-21.8).

Conclusion

Selected uncomplicated pseudocysts can be treated effectively with a single 7-Fr DPS as it provides comparable clinical success and long-term outcomes as using larger or multiple stents.

Usefulness of Routine Plain CT the Day After an Interventional EUS Procedure

BACKGROUND

Interventional endoscopic ultrasound-guided procedures (I-EUS) are widely accepted as salvage procedures in ERCP-failed cases, and to drain fluid collected in the abdominal cavity. Although I-EUS has a relatively high incidence of complications and is severe/fatal in some cases, no follow-up strategy has been established. In our institution, plain computed tomography (P-CT) is performed routinely the day after I-EUS. In this study, we evaluated the usefulness of routine P-CT the day after I-EUS, as a follow-up method, and propose an algorithm.

METHODS

We retrospectively reviewed 81 patients who underwent I-EUS and evaluated the usefulness of P-CT, abdominal X-ray, laboratory data, and symptoms as a follow-up method. An adverse event (AE) was defined as an event requiring any treatment.

RESULTS

Technical success, clinical success, and AE rates were 96.3%, 90.1%, and 18.9%, respectively. In total, 30 patients had abnormal findings among the follow-up methods: 6 cases underwent additional procedures, 8 underwent medical treatments, and 16 were observed. The sensitivity, specificity, and accuracy for detecting AEs were assessed based on P-CT (85.7%, 100%, and 97.5%), X-ray (7.1%, 100%, and 83.5%), laboratory data (71.4%, 83.0%, and 81.0%), and symptoms (92.9%, 86.2%, and 87.3%). The sensitivity and accuracy of the latter two items were as high as those for X-ray, but specificity was lower than those for X-ray and P-CT.

CONCLUSIONS

Routine P-CT the day after I-EUS was useful for detecting complications and deciding to perform an invasive salvage procedure. Symptoms and laboratory data were useful to supplement routine P-CT.

Long-term Outcomes of Direct Endoscopic Necrosectomy for Complicated or Symptomatic Walled-Off Necrosis: A Korean Multicenter Study

Background/Aims

The endoscopic step-up approach is accepted as the preferred treatment for complicated or symptomatic walled-off necrosis (WON). Direct endoscopic necrosectomy (DEN) is an effective therapeutic option, but few reports describe long-term follow-up in this patient population. Thus, we aim to assess the long-term outcomes of DEN following severe necrotizing pancreatitis.

Methods

The data of all acute pancreatitis patients who underwent DEN following endoscopic transmural drainage from six referral centers between 2007 and 2017 were retrospectively collected.

Results

Sixty patients (76.7% male, mean age 48.3 years) underwent a median of 4 sessions of DEN starting at a median of 45.5 days after the onset of acute pancreatitis. Clinical success was achieved in 51 patients (85%), with a 35% complication rate and a 5% mortality rate. Using multivariate analysis, the risk factor associated with DEN failure or major DEN complications requiring intervention or surgery was an identified bacterial/fungal WON infection (odds ratio, 19.3; 95% confidence interval, 1.5 to 261.7). During the median follow-up period of 27 months, complicated WON recurrence was observed in 5.3% of patients, and long-term complications occurred in 24.6% of patients (four exocrine insufficiency, nine newly developed diabetes mellitus, one recurrent small bowel obstruction, one chylous ascites).

Conclusions

Considering that long-term complications are similar to those observed after pancreatectomy, DEN should be performed meticulously while minimizing damage to the viable pancreatic parenchyma with adequate antibiotic escalation.

Endoscopic management of walled-off pancreatic necrosis

Walled-off pancreatic necrosis (WON) can develop in the late phase of necrotizing pancreatitis. When the WON is accompanied by an infection in the necrotic bed, it becomes a life-threatening complication. Open necrosectomy with drainage has been the standard treatment; however, it is associated with a significant morbidity and high mortality. Therefore, minimally invasive therapeutic alternatives are in demand. Recently, a new treatment algorithm for necrotizing pancreatitis, known as the step-up approach, has been proposed. The initial report on it consisted of percutaneous drainage followed by, if necessary, a minimally invasive retroperitoneal necrosectomy. However, the endoscopic step-up approach, which consists of EUS-guided transluminal drainage followed by, if necessary, endoscopic necrosectomy, was later introduced. Recent studies have suggested that an endoscopic step-up approach might be more advantageous than a minimally invasive surgical step-up approach. A lumen apposing metal stent (LAMS) with a cautery-enhanced delivery system is currently preferred over the conventional plastic stents for endoscopic interventions, because it decreases the technical difficulty of the procedure and may obviate the need for an adjunctive debridement procedure. However, some recent findings suggest that LAMS could be associated with a higher risk of stent-related complications than conventional plastic stents, especially in patients with long-term placement. Therefore, early removal of LAMS at 3 weeks post-intervention is proposed if the WON is resolved on CT examination. Thus, endoscopic interventions have emerged as a key player in the management of WON. However, multidisciplinary treatment approaches should be considered because the endoscopic approach has limitations in treating complicated WON.

Antireflux metal stent for biliary obstruction: Any benefits?

Endoscopic retrograde cholangiopancreatography with stent placement has been utilized as standard palliative management of distal malignant biliary obstruction (MBO). Compared to plastic stents, metal stents can provide longer-term relief of symptoms. When a large-bore metal stent is placed across the ampulla, patients are predisposed to the risk of cholangitis or stent dysfunction due to reflux of duodenal contents. To mitigate the risk of adverse events associated with the duodenobiliary reflux, efforts have been directed to development of antireflux metal stents (ARMSs). The antireflux property has been introduced through adding of an antireflux valve to the duodenal stent end. Evidence from clinical studies indicates that ARMSs may not only reduce the risk of ascending cholangitis during follow-up but also prolong stent patency time. However, the results of clinical studies testing ARMSs are inconsistent owing to heterogeneous designs of antireflux valves and stent bodies. Metal stents are increasingly indicated for benign biliary strictures and MBO in the setting of neoadjuvant chemotherapy, and therefore, research is warranted to evaluate ARMSs for those indications. Given that endoscopic ultrasound (EUS)-guided transmural biliary drainage has gained popularity, the optimal timing of placing an ARMS in relation to EUS-guided and percutaneous drainage should be investigated. Development and evaluation of ARMSs require an integrative approach utilizing phantom and animal models, measurements of stent mechanical properties, and in vivo functional study after stent placement. In this review article, we summarize updated evidence on ARMSs for MBO and discuss issues that should be addressed in future studies.

When Should We Perform Endoscopic Drainage and Necrosectomy for Walled-Off Necrosis?

Endoscopic drainage and necrosectomy are now accepted treatment approaches for patients with symptomatic walled-off pancreatic necrosis (WON). The current recommendations advocate step-up approaches for the treatment of symptomatic WON. Previous recommendations stipulated that endoscopic intervention should be delayed until more than four weeks after the onset. Recent data on early drainage have been increasing and this option might be considered in well-encapsulated cases, but the percutaneous route is preferred if the drainage is performed within two weeks after onset or in nonencapsulated cases. Recently, additional drainage methods, such as the multiple gateway technique and multiple stent placement, have been developed to open up multiple dead spaces in the WON cavity. Endoscopic necrosectomy could be performed via the transluminal route or percutaneous route after failed initial and additional drainage procedures. The use of novel lumen-apposing stents is a promising treatment option that could reduce the number of steps, the procedure time, and the overall number of necrosectomies.

Role of pancreatography in the endoscopic management of encapsulated pancreatic collections – review and new proposed classification

Pancreatic fluids collections are local complications related to acute or chronic pancreatitis and may require intervention when symptomatic and/or complicated. Within the last decade, endoscopic management of these collections via endoscopic ultrasound-guided transmural drainage has become the gold standard treatment for encapsulated pancreatic collections with high clinical success and lower morbidity compared to traditional surgery and percutaneous drainage. Proper understanding of anatomic landmarks, including assessment of the main pancreatic duct and any associated lesions – such as disruptions and strictures – are key to achieving clinical success, reducing the need for reintervention or recurrence, especially in cases with suspected disconnected pancreatic duct syndrome. Additionally, proper review of imaging and anatomic landmarks, including collection location, are pivotal to determine type and size of pancreatic stenting as well as approach using long-term transmural indwelling plastic stents. Pancreatography to adequately assess the main pancreatic duct may be performed by two methods: Either non-invasively using magnetic resonance cholangiopancreatography or endoscopically via retrograde cholangiopan-creatography. Despite the critical need to understand anatomy via pancrea-tography and assess the main pancreatic duct, a standardized approach or uniform assessment strategy has not been described in the literature. Therefore, the aim of this review was to clarify the role of pancreatography in the endoscopic management of encapsulated pancreatic collections and to propose a new classification system to aid in proper assessment and endoscopic treatment.

The Effect of an Invasive Strategy for Treating Pancreatic Necrosis on Mortality: a Retrospective Multicenter Cohort Study

BACKGROUND

Infected acute necrotic collections (ANC) and walled-off necrosis (WON) of the pancreas are associated with high mortality. The difference in mortality between open necrosectomy and minimally invasive therapies in these patients remains unclear.

METHODS

This retrospective multicenter cohort study was conducted among 44 institutions in Japan from 2009 to 2013. Patients who had undergone invasive treatment for suspected infected ANC/WON were enrolled and classified into open necrosectomy and minimally invasive treatment (laparoscopic, percutaneous, and endoscopic) groups. The association of each treatment with mortality was evaluated and compared.

RESULTS

Of 1159 patients with severe acute pancreatitis, 122 with suspected infected ANC or WON underwent the following treatments: open necrosectomy (33) and minimally invasive treatment (89), (laparoscopic three, percutaneous 49, endoscopic 37). Although the open necrosectomy group had a significantly higher mortality on univariate analysis (p = 0.047), multivariate analysis showed no significant associations between open necrosectomy or Charlson index and mortality (p = 0.29, p = 0.19, respectively). However, age (for each additional 10 years, p = 0.012, odds ratio [OR] 1.50, 95% confidence interval [CI] 1.09-2.06) and revised Atlanta criteria-severe (p = 0.001, OR 7.84, 95% CI 2.40-25.6) were significantly associated with mortality.

CONCLUSIONS

In patients with acute pancreatitis and infected ANC/WON, age and revised Atlanta criteria-severe classification are significantly associated with mortality whereas open necrosectomy is not. The mortality risk for patients undergoing open necrosectomy and minimally invasive treatment does not differ significantly. Although minimally invasive surgery is generally preferred for patients with infected ANC/WON, open necrosectomy may be considered if clinically indicated.

Impact of prior antibiotics on infected pancreatic necrosis microbiology in ICU patients: a retrospective cohort study

Background

Recent guidelines advise against prophylactic antibiotics in patients with necrotizing pancreatitis, advocating instead a step-up drainage and necrosectomy strategy with antibiotics as dictated by microbiological findings. However, prompt antibiotic therapy is recommended in patients with sepsis or septic shock, a possible presentation of infected pancreatic necrosis (IPN). Consequently, in many critically ill patients with IPN, pancreatic samples are collected only after broad-spectrum antibiotic therapy initiation. Whether this prior antibiotic exposure alters the microbiological findings is unknown. The main objective was to determine whether prior antibiotic exposure sterilized the samples collected during procedures for suspected IPN in patients admitted to the intensive care unit (ICU) for acute pancreatitis with suspected IPN. We retrospectively studied 56 consecutive ICU patients admitted with suspected IPN. We collected details on the microbiological samples and antimicrobials used. A definite diagnosis of IPN was given when bacteria were identified in pancreatic samples.

Results

In all, 137 pancreatic samples were collected, including 91 (66.4%) after antibiotic therapy initiation. IPN was confirmed in 48 (86%) patients. The proportion of positive samples was 74 (81.3%) in antibiotic-exposed patients and 32/46 (69.5%) in unexposed patients (p = 0.58). Of the 74 positive samples from exposed patients, 62 (84%) had organisms susceptible to the antibiotics used. One-third of samples contained more than one organism. Among patients with IPN, 37.5% had positive blood cultures. Multidrug- or extensively drug-resistant bacteria were identified at some point in half the patients. Enterobacter cloacae complex was more frequent in the exposed group (p = 0.02), as were Gram-negative anaerobic bacteria (p = 0.03).

Conclusion

Antibiotic exposure before sampling did not seem to affect culture positivity of pancreatic samples to confirm IPN, but may affect microbiological findings. Our results suggest that, in patients with sepsis and suspected IPN, antibiotics should be started immediately and pancreatic samples obtained as soon as possible thereafter. In other situations, antibiotics can be withheld until the microbiological results of pancreatic samples are available, to ensure accurate targeting of the spectrum to bacterial susceptibility patterns.

ClinicalTrials.gov number NCT03253861

Endoscopic Transmural Necrosectomy: Timing, Indications, and Methods

Walled-off necrosis is considered one of the most severe complications after an episode of severe acute pancreatitis. Traditionally, percutaneous drainage is selected as the first treatment step, while open surgery can be planned as a secondary option if necrosectomy is required. In recent years, endoscopic necrosectomy has evolved as a more favorable approach. To date, a step-up treatment strategy is recommended, particularly when a plastic stent is selected as the drainage device. Multi-gateway endoscopic therapy may be used in a step-up fashion if only one stent fails to clear debris. Over many years, there has been an evolution in stent selection, from plastic to metallic stents. Within a few years of its clinical usage, lumen-apposing stents are gaining more popularity as they offer direct endoscopic necrosectomy and only require a few sessions.

Complications of Long-Term Indwelling Transmural Double Pigtail Stent Placement for Symptomatic Peripancreatic Fluid Collections

BACKGROUND

Endoscopic transmural drainage is performed for symptomatic peripancreatic fluid collections (PPFCs). Long-term transmural double-pigtail stent (DPS) placement is useful in preventing recurrences. There are few reports on the long-term safety of DPS placement. Thus, this study aimed to examine the complications of long-term indwelling DPS for PPFCs.

METHODS

Among 53 patients who underwent endoscopic ultrasound-guided transmural drainage for symptomatic PPFCs between April 2006 and March 2017, those followed up for over one year were included. Complications of long-term indwelling DPS were examined retrospectively.

RESULTS

This study enrolled 36 patients [30 men, median age 54 years (range 22-82)]. Walled-off necrosis was present in 22 cases (including 9 disconnected pancreatic duct syndrome cases) and pancreatic pseudocysts, in 14 cases. The median stenting period was 20.9 (range 0.8-142.3) months, and median observation period was 56.2 (range 12.4-147.1) months. Colon perforation due to DPS occurred in 3 cases (8.3%), at 5.8, 17.1, and 33.7 months after indwelling DPS placement; 2 cases developed perforation from the serosal side. In 1 case, the patient was treated surgically, and in 2 cases, the patients underwent endoscopic removal of the stent and showed improvement with conservative treatment.

CONCLUSION

Long-term indwelling transmural DPS for symptomatic PPFCs poses a risk of intestinal perforation. Thus, if possible, it may be better to avoid long-term placement.

An endoscopic or minimally invasive surgical approach for infected necrotizing pancreatitis: a systematic review and meta-analysis

BACKGROUND AND AIM

the incidence of acute pancreatitis is rising across the world, thus further increasing the burden on healthcare services. Approximately 10% of patients with acute pancreatitis will develop infected necrotizing pancreatitis (INP), which is the leading cause of high mortality in the late phase. There is currently no consensus with regard to the use of endoscopic or minimally invasive surgery as the first-line therapy of choice for INP. However, more clinical research with regard to the superiority of an endoscopic approach has been recently published. Therefore, we conducted a systematic review and meta-analysis to determine which of the two treatments leads to a better prognosis.

METHODS

four databases (Medline, SINOMED, EMBASE and Cochrane Library) were searched for eligible studies from 1980 to 2018, comparing endoscopic and minimally invasive surgery for INP.

RESULTS

two randomized controlled trials (RCTs) and seven clinical cohort studies were included. After the analysis of data amenable to polling, significant advantages were found in favor of the endoscopic approach in terms of pancreatic fistulas (OR = 0.10, 95% CI 0.04-0.30, p < 0.001) and the length of hospital stay (weighted mean difference [WMD] = -24.72, 95% CI = -33.87 to -15.57, p < 0.001). No marked differences were found in terms of mortality, multiple organ failure, intra-abdominal bleeding, enterocutaneous fistula, recurrence of pseudocysts, and length of stay (LOS) in the Intensive Care Unit (ICU), endocrine insufficiency and exocrine insufficiency.

CONCLUSION

compared with minimally invasive surgery, an endoscopic approach evidently improved short-term outcomes for infected necrotizing pancreatitis, including pancreatic fistula and the length of hospital stay. Furthermore, relevant multicenter RCTs are eager to validate these findings.

An overview of walled-off pancreatic necrosis for clinicians

Walled of pancreatic necrosis (WOPN) is a new term coined for encapsulated fluid collection developing after acute necrotising pancreatitis (ANP). It is a heterogeneous collection containing varying amount of liquid as well as solid necrotic material. The literature on its natural history as well as appropriate management is gradually expanding thereby improving treatment outcomes of this enigmatic disease. Areas covered: This review discusses currently available literature on etiology, frequency, natural history, and imaging features WOPN. Also, updated treatment options including endoscopic, radiological and surgical drainage are discussed. Expert opinion: WOPN is alocal complication of ANP occurring in the delayed phase of ANP and may be asymptomatic (50%) or present with pain, fever, jaundice, or gastric outlet obstruction. Natural courses of asymptomatic WOPN have been infrequently studied, and it appears that the majority remain asymptomatic and resolve spontaneously. Magnetic resonance imaging and endoscopic ultrasound are the best imaging modalities to evaluate solid necrotic debris. Symptomatic WOPN usually needs immediate drainage, this can be done endoscopically, radiologically, or surgically. Current evidence suggests that endoscopic transluminal drainage is the preferred drainage technique as it is effective and associated with lower mortality, risk of organ failure, adverse effects, and length of hospital stay.

Comparison of early and delayed EUS-guided drainage of pancreatic fluid collection

Background and study aims  While endoscopic ultrasound (EUS)-guided drainage of pancreatic fluid collection (PFC) is recommended to be performed ≥ 4 weeks after onset of acute pancreatitis (AP), early (< 4 weeks) interventions are needed in some symptomatic cases. Despite feasibility of early percutaneous drainage, there have been few studies about early EUS-guided drainage of PFC. Patients and methods  Consecutive patients who received EUS-guided drainage (EUS-PCD) of infected or symptomatic PFC at the University of Tokyo were retrospectively studied. Contraindications for EUS-PCD are lack of encapsulation or adhesion to the gastrointestinal tract. Safety and effectiveness of early vs delayed (≥ 4 weeks) EUS-PCD were compared. Results  A total of 35 patients underwent EUS-PCD (12 early and 23 delayed) using 19 large-bore fully-covered metallic stent and 16 plastic stents. The median diameter of PFC was 110 mm (40 - 180) and 122 mm (17 - 250) in the early and delayed drainage groups, respectively. Median time from onset of AP to drainage was 23 and 85 days for early and delayed drainage, respectively. The technical success rate of EUS-guided drainage was 100 %. Endoscopic necrosectomy was performed in six early and 16 cases of delayed drainage. The adverse event rate was 25 % (3 bleeding) and 13 % (2 perforations and 1 CO ₂ retention) in the early and delayed drainage groups, respectively. Two patients died (1 early and 1 delayed) due to multiorgan failure. Conclusion  Endoscopic drainage and subsequent necrosectomy of symptomatic PFC within 4 weeks after onset of acute pancreatitis was feasible, given that the collection was encapsulated and attached to the gastrointestinal tract.

Duration of antibiotic treatment after endoscopic ultrasound-guided drainage of walled-off pancreatic necrosis not affecting outcomes

BACKGROUND AND AIM

Although society guidelines recommend a short course of antibiotics after drainage of walled-off necrosis (WON), the exact duration is unclear.

METHODS

This is a retrospective review of patients with no prior antibiotic exposure who underwent dual-modality drainage (DMD) for sterile WON from 2008 to 2017. Patients were grouped into short duration (SD, ≤5 days) versus long duration (LD, >5 days). The main outcome was the frequency of recurrent infections.

RESULTS

Sixty-one patients (25 in the SD group and 36 in the LD group) were included. Patients in the two groups had comparable age, comorbidities, and severity of disease (P = 0.89). Patients in the SD group were treated with antibiotics for a median of 3 days compared with 8.5 days in the LD group. There were no differences in recurrent febrile episodes within 30 days of procedure-44% of SD group versus 39% of LD (P = 0.69). There was also no difference in time to resolution of WON (64 days for both groups, P = 0.72) or duration of hospitalization post-DMD (SD 7.7 days versus LD 7.5 days, P = 0.42). Three cases of Clostridium difficile colitis were observed in the LD group.

CONCLUSIONS

Longer course of antibiotics seems to have similar outcomes compared with shorter courses in patients with WON treated with DMD. Prolonged-course therapy may predispose to secondary infections like C. difficile colitis. A randomized controlled trial is needed to evaluate the role and duration of peri-procedural antibiotics after drainage of sterile WON.

International study of endoscopic management of distal malignant biliary obstruction combined with duodenal obstruction

OBJECTIVE

Endoscopic transpapillary or endoscopic ultrasound (EUS)-guided stent placement is used for nonresectable distal malignant biliary obstruction. We conducted a retrospective study to evaluate endoscopic biliary drainage in patients with duodenal obstruction.

METHODS

We included consecutive patients who underwent endoscopic biliary drainage combined with a duodenal stent at 16 referral centers in four Asian countries. The primary outcome was time to recurrent biliary obstruction (TRBO). We assessed TRBO according to the sequence of biliary and duodenal obstruction (group 1/2/3, biliary obstruction first/concurrent/duodenal obstruction first, respectively) or the location of duodenal obstruction (type I/II/III, proximal to/affecting/distal to the ampulla, respectively). We also evaluated functional success and adverse events.

RESULTS

We included 110 patients (group1/2/3, 67/29/14 patients; type I/II/III, 45/46/19 patients; endoscopic retrograde cholangiopancreatography [ERCP]/EUS-guided choledocoduodenostomy/EUS-guided hepaticogastrostomy, 90/10/10 patients, respectively). The median TRBO of all cases was 450 days (interquartile range, 212-666 days) and functional success was achieved in 105 cases (95%). The TRBO did not differ significantly by the timing or location of duodenal obstruction (p = .30 and .79, respectively). The TRBO of metal stents (n = 96) tended to be longer compared with plastic stents (n = 14, p = .083). Compared with ERCP, EUS-guided biliary drainage was associated with a higher rate of adverse events.

CONCLUSION

Transpapillary or transmural endoscopic biliary drainage with a duodenal stent was effective, irrespective of the timing or location of duodenal obstruction. A prospective study is required considering the tradeoff of technical success rate, stent patency, and adverse events (ClinicalTrials.gov number, NCT02376907).

Update: Role of surgery in acute necrotizing pancreatitis

Acute necrotizing pancreatitis is a prevalent disease with high morbidity and mortality. The development of radiologic and endoscopic techniques to manage pancreatic necrosis commands a multidisciplinary approach, which has considerably decreased the need for laparotomy. The objective of this update is to define the role of surgery in the multidisciplinary approach to management of necrotizing acute pancreatitis.

Endoscopic ultrasonography-guided drainage of pancreatic fluid collections

Endoscopic ultrasound (EUS)-guided drainage is now firmly established as the best option for drainage of walled-off pancreatic fluid collections (PFC). It has high clinical efficacy, similar to surgical and percutaneous approaches, but with lower morbidity and costs. It is superior to non-EUS-guided approaches because even collections without endoluminal bulging can be successfully drained. Transmural drainage alone is sufficient for pseudocysts, but in the context of walled-off pancreatic necrosis (WON), adjunctive direct endoscopic necrosectomy (DEN) may be required. Traditionally, double pigtail plastic stents (PS) were used for transmural drainage, but, recently, fully covered self-expandable metallic stents (FCSEMS) customized for PFC drainage have become available and are increasingly used, especially in the management of WON, because the larger-diameter stent facilitates drainage and insertion of an endoscope into the WON cavity for DEN. The present review will discuss the evidence for EUS-guided drainage and DEN, the technical problems involved, and the roles of PS and FCSEMS in PFC drainage.