The role of intraductal US in the management of idiopathic recurrent pancreatitis without a definite cause on ERCP

Endoscopic Ultrasound to Identify the Actual Cause of Idiopathic Acute Pancreatitis: A Systematic Review

Idiopathic acute pancreatitis (IAP) presents a diagnostic challenge and refers to cases where the cause of acute pancreatitis remains uncertain despite a comprehensive diagnostic evaluation. Endoscopic ultrasound (EUS) has emerged as a valuable tool in the diagnostic workup of IAP. This review explores the pivotal role of EUS in detecting the actual cause of IAP and assessing its accuracy, timing, safety, and future technological improvement. In this review, we investigate the role of EUS in identifying the actual cause of IAP by examining the available literature. We aim to assess possible existing evidence regarding EUS accuracy, timing, and safety and explore potential trends of future technological improvements in EUS for diagnostic purposes. Following PRISMA guidelines, 60 pertinent studies were selected and analysed. EUS emerges as a crucial diagnostic tool, particularly when conventional imaging fails. It can offer intricate visualization of the pancreas, biliary system, and adjacent structures. Microlithiasis, biliary sludge, chronic pancreatitis, and small pancreatic tumors seem to be much more accurately identified with EUS in the setting of IAP. The optimal timing for EUS is post-resolution of the acute phase of the disease. With a low rate of complications, EUS poses minimal safety concerns. EUS-guided interventions, including fine-needle aspiration, collection drainage, and biopsies, aid in the cytological analysis. With high diagnostic accuracy, safety, and therapeutic potential, EUS is able to improve patient outcomes when managing IAP. Further refinement of EUS techniques and cost-effectiveness assessment of EUS-guided approaches need to be explored in multicentre prospective studies. This review underscores EUS as a transformative tool in unraveling IAP's enigma and advancing diagnostic and therapeutic strategies.

Utility of endoscopic ultrasound in idiopathic acute recurrent pancreatitis

Idiopathic acute recurrent pancreatitis (IARP) is defined as at least two episodes of acute pancreatitis with the complete or near-complete resolution of symptoms and signs of pancreatitis between episodes, without an identified cause. There is a paucity of information about the usefulness of endoscopic ultrasound (EUS) in IARP.

Endoscopic ultrasonography can detect a cause in the majority of patients with idiopathic acute pancreatitis: a systematic review and meta-analysis

BACKGROUND

Idiopathic acute pancreatitis (IAP) has a 25 % pancreatitis recurrence rate. Endoscopic ultrasonography (EUS) may diagnose treatable causes of IAP and hence prevent recurrence. The goal of this systematic review with meta-analysis is to determine the diagnostic yield of EUS and its impact on recurrence.

METHODS

PubMed, EMBASE and the Cochrane Library were systematically searched for English studies on EUS in adults with IAP. The primary outcome was diagnostic yield. Secondary outcomes included recurrence. Methodological quality was assessed using the QUADAS-2 score. Meta-analysis was performed to calculate the pooled diagnostic yield and risk ratio with 95 % confidence intervals (CI) using a random-effects model with inverse variance method.

RESULTS

22 studies were included, with 1490 IAP patients who underwent EUS. Overall diagnostic yield was 59 % (874 /1490; 95 %CI 52 % - 66 %). The most common etiologies were biliary (429 /1490; 30 %, 95 %CI 21 % - 41 %) and chronic pancreatitis (271 /1490; 12 %, 95 %CI 8 % - 19 %). In 2 % of patients, neoplasms were detected (45 /1490; 95 %CI 1 % - 4 %). There was no difference in yield between patients with or without recurrent IAP before EUS (risk ratio 0.89, 95 %CI 0.71 - 1.11).

CONCLUSIONS

EUS is able to identify a potential etiology in the majority of patients with IAP, detecting mostly biliary origin or chronic pancreatitis, but also neoplasms in 2 % of patients. EUS may be associated with a reduction of recurrence rate. Future studies should include complete diagnostic work-up and preferably include patients with a first episode of IAP only.

Urgent endoscopic retrograde cholangiopancreatography with sphincterotomy versus conservative treatment in predicted severe acute gallstone pancreatitis (APEC): a multicentre randomised controlled trial

BACKGROUND

It remains unclear whether urgent endoscopic retrograde cholangiopancreatography (ERCP) with biliary sphincterotomy improves the outcome of patients with gallstone pancreatitis without concomitant cholangitis. We did a randomised trial to compare urgent ERCP with sphincterotomy versus conservative treatment in patients with predicted severe acute gallstone pancreatitis.

METHODS

In this multicentre, parallel-group, assessor-masked, randomised controlled superiority trial, patients with predicted severe (Acute Physiology and Chronic Health Evaluation II score ≥8, Imrie score ≥3, or C-reactive protein concentration >150 mg/L) gallstone pancreatitis without cholangitis were assessed for eligibility in 26 hospitals in the Netherlands. Patients were randomly assigned (1:1) by a web-based randomisation module with randomly varying block sizes to urgent ERCP with sphincterotomy (within 24 h after hospital presentation) or conservative treatment. The primary endpoint was a composite of mortality or major complications (new-onset persistent organ failure, cholangitis, bacteraemia, pneumonia, pancreatic necrosis, or pancreatic insufficiency) within 6 months of randomisation. Analysis was by intention to treat. This trial is registered with the ISRCTN registry, ISRCTN97372133.

FINDINGS

Between Feb 28, 2013, and March 1, 2017, 232 patients were randomly assigned to urgent ERCP with sphincterotomy (n=118) or conservative treatment (n=114). One patient from each group was excluded from the final analysis because of cholangitis (urgent ERCP group) and chronic pancreatitis (conservative treatment group) at admission. The primary endpoint occurred in 45 (38%) of 117 patients in the urgent ERCP group and in 50 (44%) of 113 patients in the conservative treatment group (risk ratio [RR] 0·87, 95% CI 0·64-1·18; p=0·37). No relevant differences in the individual components of the primary endpoint were recorded between groups, apart from the occurrence of cholangitis (two [2%] of 117 in the urgent ERCP group vs 11 [10%] of 113 in the conservative treatment group; RR 0·18, 95% CI 0·04-0·78; p=0·010). Adverse events were reported in 87 (74%) of 118 patients in the urgent ERCP group versus 91 (80%) of 114 patients in the conservative treatment group.

INTERPRETATION

In patients with predicted severe gallstone pancreatitis but without cholangitis, urgent ERCP with sphincterotomy did not reduce the composite endpoint of major complications or mortality, compared with conservative treatment. Our findings support a conservative strategy in patients with predicted severe acute gallstone pancreatitis with an ERCP indicated only in patients with cholangitis or persistent cholestasis.

FUNDING

The Netherlands Organization for Health Research and Development, Fonds NutsOhra, and the Dutch Patient Organization for Pancreatic Diseases.

Prospective Comparison of Intraductal Ultrasonography-Guided Transpapillary Biopsy and Conventional Biopsy on Fluoroscopy in Suspected Malignant Biliary Strictures

Background/Aims

In suspected malignant biliary strictures (MBSs), the diagnostic yield of endoscopic retrograde cholangiopancreatography (ERCP)-based tissue sampling is limited. Transpapillary forceps biopsy (TPB) under intraductal ultrasonography (IDUS) guidance is expected to improve the diagnostic accuracy in patients with indeterminate biliary strictures. We evaluated the usefulness of IDUS-guided TPB in patients with suspected MBS.

Methods

Consecutive patients with suspected MBS were prospectively enrolled in the study. ERCP with IDUS was performed in all patients. Both conventional TPB and IDUS-guided TPB on fluoroscopy were performed in each patient. The primary outcome was the diagnostic accuracy of conventional TPB and IDUS-guided TPB.

Results

The technical success rate of IDUS-guided TPB was 97.0% (65/67 patients). Of these 65 patients, the final diagnosis was malignancy in 61 patients (93.8%). On IDUS, the most common finding of IDUS was an intraductal infiltrating lesion in 29 patients (47.5%). The overall diagnostic accuracy was significantly higher using IDUS-guided TPB than that using conventional TPB (90.8% vs 76.9%, p=0.027). According to the subgroup analysis based on the tumor morphology, IDUS-guided TPB had a significantly higher cancer detection rate than conventional TPB for intraductal infiltrating lesions (89.6% vs 65.5%, p=0.028).

Conclusions

IDUS-guided TPB appears to improve the accuracy of histological diagnosis in patients with MBS.

Comparison of EUS with MRCP in idiopathic acute pancreatitis: a systematic review and meta-analysis

BACKGROUND AND AIMS

Idiopathic acute pancreatitis (IAP) poses a diagnostic challenge for gastroenterologists, because confirmation of the disease etiology has important implications for the selection of the best possible treatment and the prevention of possible recurrence or the development of chronic pancreatitis (CP). ERCP, EUS, and MRCP typically are used to diagnose IAP when conventional radiologic methods fail. However, their exact role in the diagnosis of IAP has not yet been determined.

METHODS

We searched the PubMed, EMBASE, OVID, Cochrane Library (including CENTRAL), China National Knowledge Infrastructure (CNKI), and Wanfang databases from inception to April 2017. Studies involving the use of EUS and/or MRCP for the etiologic diagnosis of IAP were included. A meta-analysis was performed by using Review Manager Version 5.2 for comparative studies and R software 3.3.3 to determine diagnostic yield of the studies.

RESULTS

Among the 34 studies that met the inclusion criteria (n = 2338), 7 studies used a combination of EUS and MRCP and totaled 249 patients. The results comparing EUS with MRCP showed a diagnostic yield of 153 of the 239 patients (64%) in the EUS group, which was higher than the yield of 82 of 238 patients (34%) in the MRCP group (P < .001) in the 7 studies, and the diagnostic yield was 60% in the EUS group, 24% in the MRCP group, and 43% in the MRCP after secretin stimulation (S-MRCP) group. In our subgroup analysis of CP and biliary disease, EUS was superior to MRCP (P < .001), but when comparing the efficacy of the modalities in the diagnosis of pancreatic divisum, S-MRCP was obviously superior to MRCP and EUS (12% vs 2% vs 2%).

CONCLUSION

EUS and MRCP should both be used in the diagnostic work-up of IAP as complementary techniques. EUS had a higher diagnostic accuracy than MRCP (64% vs 34%) in the etiologic diagnosis of IAP and should be preferred for establishing a possible biliary disease and CP diagnosis, whereas S-MRCP was superior to EUS and MRCP in diagnosing a possible anatomic alteration in the biliopancreatic duct system, such as pancreatic divisum.

The Role of Endoscopic Biliary Drainage without Sphincterotomy in Gallstone Patients with Cholangitis and Suspected Common Bile Duct Stones Not Detected by Cholangiogram or Intraductal Ultrasonography

Background/Aims

Treatment for cholangitis without common bile duct (CBD) stones has not been established in patients with gallstones. We investigated the usefulness of endoscopic biliary drainage (EBD) without endoscopic sphincterotomy (EST) in patients diagnosed with gallstones and cholangitis without CBD stones by endoscopic retrograde cholangiopancreatography (ERCP) and intraductal ultrasonography (IDUS).

Methods

EBD using 5F plastic stents without EST was performed prospectively in patients with gallstones and cholangitis if CBD stones were not diagnosed by ERCP and IDUS. After ERCP, all patients underwent laparoscopic cholecystectomy. The primary outcomes were clinical and technical success. The secondary outcomes were recurrence rate of biliary events and procedure-related adverse events.

Results

Among 187 patients with gallstones and cholangitis, 27 patients without CBD stones according to ERCP and IDUS received EBD using 5F plastic stents without EST. The stents were maintained in all patients until laparoscopic cholecystectomy, and recurrence of cholangitis was not observed. After cholecystectomy, the stents were removed spontaneously in 12 patients and endoscopically in 15 patients. Recurrence of CBD stones was not detected during the follow-up period (median, 421 days).

Conclusions

EBD using 5F plastic stents without EST may be safe and effective for the management of cholangitis accompanied by gallstones in patients without CBD stones according to ERCP and IDUS.

The role of intraductal ultrasonography in pancreatobiliary diseases

Intraductal ultrasonography (IDUS) provides real-time, cross-sectional imaging of pancreatobiliary ducts and surrounding structures during endoscopic retrograde cholangiopancreatography using a high-frequency ultrasound (US) transducer. Hence, IDUS has been considered a sensitive tool in the evaluation of suspicious choledocholithiasis and neoplasms, to help distinguish between benign and malignant bile duct strictures or wall thickness, and to assess tumor extension and invasion depth. With the rapid development and enriched choices of sensitive diagnostic modalities include but are not limited to endoscopic US, peroral cholangioscopy, and confocal laser endomicroscopy, it is needed to systematically assess the role of IDUS in the investigation of pancreatobiliary diseases. Some new developments and innovative use of IDUS techniques will be discussed in this paper with the review of literature.

Clinical usefulness of intraductal ultrasonography for the management of acute biliary pancreatitis

BACKGROUND AND AIM

Identifying a bile duct (BD) stone in patients with acute biliary pancreatitis (ABP) is important for the management and prevention of recurrent attack of pancreatitis. However, small BD stones may not be detected on endoscopic retrograde cholangiopancreatography (ERCP). The aim of this study was to prospectively evaluate the usefulness of intraductal ultrasonography (IDUS) in patients suspected to have ABP but with no evidence of choledocholithiasis on ERCP.

METHODS

A total 92 patients suspected with ABP without evidence of BD stones on imaging studies including ERCP were enrolled. Wire-guided IDUS was performed during ERCP in all patients. Stones or sludge detected by IDUS were confirmed after endoscopic sphincterotomy (EST) and extraction. If IDUS finding was negative, then we swept the BD with a balloon catheter and/or basket without EST. After endoscopic management, comparison between IDUS and endoscopic finding was carried out to determine the diagnostic accuracy of IDUS.

RESULTS

Among the 92 patients, IDUS revealed BD stones in 33 (35.9%). All 33 patients' stones were confirmed by endoscopic visualization after EST and BD exploration. During the mean follow up of 24 months, recurrent pancreatitis did not occur in 90 of 92 patients (97.9%) with ABP after endoscopic treatment according to the IDUS findings.

CONCLUSIONS

IDUS improves diagnostic accuracy for the detection of clinically occult BD stones in patients suspicious ABP. IDUS-guided endoscopic management for patients with ABP can avoid unnecessary EST and help prevent recurrent pancreatitis.

The role of endoscopic retrograde cholangiopancreatography in patients with pancreatic disease

Given the significant risk of pancreatitis and the advent of high-fidelity diagnostic techniques, ERCP is now reserved as a therapeutic procedure for those with pancreatic disease. Early ERCP benefits those with gallstone pancreatitis who present with or develop cholangitis or biliary obstruction. Among those with idiopathic pancreatitis, ERCP may be used to confirm and treat SOD, microlithiasis, and structural anomalies, including pancreas divisum. Pancreatic endotherapy is a consideration to decrease pain in those with pancreatic duct obstruction, although surgical decompression may be more durable, particularly in those with severe disease. Pancreatic duct leaks may respond to endoscopic drainage, but optimal therapy is achieved if a bridging stent can be placed. Finally, using a wire-guided technique and pancreatic duct stents in high-risk patients, particularly in cases of suspected SOD, may minimize the risk of post-ERCP pancreatitis.