An assessment of existing risk stratification guidelines for the evaluation of patients with suspected choledocholithiasis

A machine learning-based choledocholithiasis prediction tool to improve ERCP decision making: a proof-of-concept study

BACKGROUND

Previous studies demonstrated limited accuracy of existing guidelines for predicting choledocholithiasis, leading to overutilization of endoscopic retrograde cholangiopancreatography (ERCP). More accurate stratification may improve patient selection for ERCP and allow use of lower-risk modalities.

METHODS

A machine learning model was developed using patient information from two published cohort studies that evaluated performance of guidelines in predicting choledocholithiasis. Prediction models were developed using the gradient boosting model (GBM) machine learning method. GBM performance was evaluated using 10-fold cross-validation and area under the receiver operating characteristic curve (AUC). Important predictors of choledocholithiasis were identified based on relative importance in the GBM.

RESULTS

1378 patients (mean age 43.3 years; 61.2% female) were included in the GBM and 59.4% had choledocholithiasis. Eight variables were identified as predictors of choledocholithiasis. The GBM had accuracy of 71.5% (SD 2.5%) (AUC 0.79 [SD 0.06]) and performed better than the 2019 American Society for Gastrointestinal Endoscopy (ASGE) guidelines (accuracy 62.4% [SD 2.6%]; AUC 0.63 [SD 0.03]) and European Society of Gastrointestinal Endoscopy (ESGE) guidelines (accuracy 62.8% [SD 2.6%]; AUC 0.67 [SD 0.02]). The GBM correctly categorized 22% of patients directed to unnecessary ERCP by ASGE guidelines, and appropriately recommended as the next management step 48% of ERCPs incorrectly rejected by ESGE guidelines.

CONCLUSIONS

A machine learning-based tool was created, providing real-time, personalized, objective probability of choledocholithiasis and ERCP recommendations. This more accurately directed ERCP use than existing ASGE and ESGE guidelines, and has the potential to reduce morbidity associated with ERCP or missed choledocholithiasis.

Endoscopic ultrasound avoids diagnostic ERCP among the ASGE high-risk group - Experience in an Asian population

BACKGROUND

A prediction system for common bile duct (CBD) stones was originally published by the American Society for Gastrointestinal Endoscopy (ASGE) in 2010 and was last revised in 2019. We wanted to investigate its application in an Asian population, who have different etiologies of bile duct stone formation and accessibility to medical service compared to the West.

METHODS

This is a single center retrospective study. Patients who received endoscopic ultrasound (EUS) for suspected CBD stones were collected from our endoscopic record system over a 10-year period. The accuracy of the revised ASGE criteria was estimated according to the results of EUS. A minimum follow-up of 6 months was required to detect false negative results.

RESULTS

142 patients were enrolled, 87 (61%) patients had CBD stones. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the revised ASGE criteria for high-risk patients were 69%, 38%, 64%, 44%, and 57%. 36% of the ASGE-defined high-risk patients negative for CBD stones on EUS. The two significant predictors for CBD stone were CBD dilatation (adjusted OR 3.06, 95% C.I. 1.31-7.17, p = 0.010) and ascending cholangitis (adjusted OR 2.28, 95% C.I. 1.01-5.15, p = 0.047).

CONCLUSION

ASGE recommends that patients defined as high-risk for choledocholithiasis be considered for direct ERCP without prior need for confirmation imaging. However, our findings indicate a high rate (36%) of patients in that group negative for CBD stones on EUS. Hence, EUS is still be suggested first in selective high-risk patients so that diagnostic ERCP can be avoided in our Asian society.

Performance of European and American Societies of Gastrointestinal Endoscopy Guidelines for Prediction of Choledocholithiasis in Patients with Acute Biliary Pancreatitis

Background and Objectives: Up to one-third of patients with acute biliary pancreatitis also present with choledocholithiasis. Guidelines from the European Society of Gastrointestinal Endoscopy (ESGE) and the American Society for Gastrointestinal Endoscopy (ASGE) for investigating suspected choledocholithiasis suggest endoscopic retrograde cholangiopancreatography in patients with high-likelihood (ESGE)/high-probability (ASGE) predictors and endoscopic ultrasound in those with intermediate-likelihood (ESGE)/intermediate-probability (ASGE) predictors. Although both guidelines are similar, they are not identical. Furthermore, these algorithms were mainly developed from cohorts of patients without pancreatitis and are therefore poorly validated in a subset of patients with acute pancreatitis. We aimed to assess the performance of the ESGE and ASGE algorithms for the prediction of choledocholithiasis in patients with acute biliary pancreatitis. Materials and Methods: This was a retrospective analysis of 86 consecutive patients admitted to a tertiary referral centre in the year 2020 due to acute biliary pancreatitis. Results: Choledocholithiasis was confirmed in 29/86 (33.7%) of patients (13 with endoscopic retrograde cholangiopancreatography and 16 with endoscopic ultrasound). All 10/10 (100%) ESGE high-likelihood and 14/19 (73.7%) ASGE high-probability patients had choledocholithiasis. Only 19/71 (26.8%) patients with ESGE intermediate likelihood and 15/67 (22.4%) with ASGE intermediate probability had choledocholithiasis. Only 8/13 (61.5%) patients with the ASGE high-probability predictor of dilated common bile duct plus bilirubin > 68.4 µmol/mL had choledocholithiasis. Since this predictor is not considered high likelihood by ESGE, this resulted in a superior specificity of the European compared to the American guideline (100% vs. 91.2%). Following the American instead of the European guidelines would have resulted in five unnecessary endoscopic retrograde cholangiopancreatographies and five unnecessary endoscopic ultrasound examinations. Conclusions: This retrospective analysis suggests that the European guidelines may perform better than the American guidelines at predicting choledocholithiasis in the setting of acute pancreatitis. This was because dilated common bile duct plus bilirubin > 68.4 µmol/mL was not a reliable predictor for persistent bile duct stones.

Prospective validation of the Israeli Score for the prediction of common bile duct stones in patients with acute calculous cholecystitis

BACKGROUND

Existing guidelines for predicting common bile duct stones (CBDS) are not specific for acute calculous cholecystitis (ACC). This paper is a posthoc analysis of the S.P.Ri.M.A.C.C study aiming to prospectively validate on a large independent cohort of patients the Israeli Score (IS) in predicting CBDS in patients with ACC.

METHODS

The S.P.Ri.M.A.C.C. study is an observational multicenter prospective study endorsed by the World Society of Emergency Surgery (WSES). Between September 1st, 2021, and September 1st, 2022, 1201 participants were included. The Chi-Square test was used to compare categorical data. A Cochran-Armitage test was run to determine whether a linear trend existed between the IS and the presence of CBDS. To assess the accuracy of the prediction model, the receiver operating characteristic (ROC) curve was generated, and the area under the ROC curve (AUC) was calculated. Logistic regression was run to obtain Odds Ratio (OR). A two-tailed p < 0.05 was considered statistically significant.

RESULTS

The rate of CBDS was 1.8% in patients with an IS of 0, 4.2% in patients with an IS of 1, 24.5% in patients with 2 and 56.3% in patients with 3 (p < 0.001). The Cochran-Armitage test of trend showed a statistically significant linear trend, p < 0.001. Patients with an IS of 3 had 64.4 times (95% CI 24.8-166.9) higher odds of having associated CBDS than patients with an IS of 0. The AUC of the ROC curve of IS for the prediction of CBDS was 0.809 (95% CI 0.752-0.865, p < 0.001). By applying the highest cut-off point (3), the specificity reached 99%, while using the lowest cut-off value (0), the sensitivity reached 100%.

CONCLUSION

The IS is a reliable tool to predict CBDS associated with ACC. The algorithm derived from the IS could optimize the management of patients with ACC.

ACR Appropriateness Criteria® Abnormal Liver Function Tests

Liver function tests are commonly obtained in symptomatic and asymptomatic patients. Various overlapping lab patterns can be seen due to derangement of hepatocytes and bile ducts function. Imaging tests are pursued to identify underlying etiology and guide management based on the lab results. Liver function tests may reveal mild, moderate, or severe hepatocellular predominance and can be seen in alcoholic and nonalcoholic liver disease, acute hepatitis, and acute liver injury due to other causes. Cholestatic pattern with elevated alkaline phosphatase with or without elevated γ-glutamyl transpeptidase can be seen with various causes of obstructive biliopathy. Acute or subacute cholestasis with conjugated or unconjugated hyperbilirubinemia can be seen due to prehepatic, intrahepatic, or posthepatic causes. We discuss the initial and complementary imaging modalities to be used in clinical scenarios presenting with abnormal liver function tests. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Performance of the predictive criteria of the American Society for Gastrointestinal Endoscopy in the diagnosis of choledocholithiasis at a secondary care public hospital in the State of Nuevo León, Mexico

INTRODUCTION AND AIMS

Currently there is no ideal diagnostic/therapeutic approach for patients with suspected choledocholithiasis. The primary aim of our study was to evaluate the performance of the criteria for predicting choledocholithiasis proposed by the American Society for Gastrointestinal Endoscopy (ASGE) in 2019.

MATERIALS AND METHODS

A retrospective study was conducted that included 352 patients seen at a secondary care public healthcare institution in Monterrey, Nuevo León, that treats an open population and does not have endoscopic ultrasound or magnetic resonance cholangiopancreatography at its disposal.

RESULTS

The most frequent predictor presented by the patients was abnormal liver function tests (90.63%), and with their use alone, sensitivity was higher than that of all the predictors analyzed (91.41%). In addition, the finding of common bile duct stones on ultrasound imaging was the only predictor independently associated with the confirmatory diagnosis of choledocholithiasis. Regarding the general performance of the 2019 criteria, the high-risk category had 68.75% sensitivity, 52.08% specificity, a positive predictive value of 79.28%, a negative predictive value of 38.46%, diagnostic accuracy of 64.20%, and a confirmatory diagnosis of choledocholithiasis in 79.28% of the patients of that risk category.

CONCLUSIONS

The study corroborated that the presence of choledocholithiasis could be predicted using the choledocholithiasis predictors and risk categories proposed by the ASGE, with acceptable accuracy, in accordance with the standards suggested by those same guidelines.

Dynamic changes in liver function tests do not correctly reclassify patients at risk of choledocholithiasis beyond ASGE 2019 criteria

Introduction

Dynamic changes in liver function tests have been proposed to correctly reclassify the risk of choledocholithiasis; however, information is scarce and insufficient to recommend its use.

Methods

Retrospective cohort of patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) due to moderate and high risk of choledocholithiasis according to the 2019 American Society of Gastrointestinal Endoscopy (ASGE) guidelines. We evaluated whether significant changes in liver function tests (bilirubin, transaminases, or alkaline phosphatase), defined as an increase or a reduction ⩾30 or ⩾50% between two measurements taken with a difference of 24-72 h can correctly reclassify the risk of choledocholithiasis beyond the ASGE guidelines. The net reclassification index (NRI) was calculated for patients with and without choledocholithiasis.

Results

Among 1175 patients who underwent ERCP, 170 patients were included in the analysis (59.4% women, median 59.5 years). Among patients without a diagnosis of choledocholithiasis, the number of patients correctly reclassified by transaminases was slightly higher than those incorrectly reclassified (NRI = 0.24 for aspartate amino transaminase and 0.20 for alanine amino transaminase). However, among patients with a diagnosis of choledocholithiasis, it led to incorrect reclassification in a greater number of cases (NRI = -0.21 and -0.14, respectively). The benefits of reclassification were minimal for bilirubin and alkaline phosphatase, or for value changes >50%. A subgroup analysis showed similar findings in patients without a history of cholecystectomy and in those with normal bile duct.

Conclusion

Dynamic changes in liver function tests do not improve choledocholithiasis risk classification beyond the 2019 ASGE criteria. New criteria should continue to be sought to optimize risk stratification.

Test Performance Characteristics of Dynamic Liver Enzyme Trends in the Prediction of Choledocholithiasis

(1) Background: Various methods to predict the presence or absence of choledocholithiasis (CDL) have been proposed. We aimed to assess the performance characteristics of dynamic liver enzyme trends in the prediction of CDL. (2) Methods: This was a single-center retrospective cohort study. All adult in-patients undergoing endoscopy for suspected CDL between 1 January 2012 and 7 October 2018 were identified, with patients with prior cholecystectomy, prior sphincterotomy, or indwelling biliary prostheses were excluded. Available laboratory parameters within 72 h preceding the procedure were recorded, allowing for the assessment of trends. Dynamic enzyme trends were defined as any increase or decrease by 30% and 50% within 72 h of the index procedure. (3) Results: A total of 878 patients were included. Mean age was 61.8 years, with 58.6% female. Increases in alkaline phosphatase (ALP) of at least 30% or 50% were both specific for the presence of CDL, with specificities of 82.7% (95% CI 69.7–91.8%) and 88.5% (95% CI 76.6–95.6%), respectively. Decreases in bilirubin or ALP of at least 50% were highly specific for the absence of CDL, with specificities of 91.7% (95% CI 85.7–95.8%) and 100.0% (97.2–100.0%), respectively. (4) Conclusions: Several liver enzyme trends appear to be specific for the absence or presence of stones; in particular, significant decreases in total bilirubin or ALP of at least 30–50% over the prior 72 h appear to be especially predictive of an absence of intraductal findings during endoscopy.

A retrospective analysis of magnetic resonance cholangiopancreatography investigating gallstones in a contemporary surgical setting

BACKGROUNDS

The New Zealand Public Health System operates in a resource limited environment. Pre-operative investigation of choledocholithiasis (CDL) is variable. Protocol driven practice has improved patient outcomes and cost-effectiveness. The aim is to explore risk stratification for CDL and specific thresholds for accessing magnetic resonance cholangiopancreatography (MRCP) in this contemporary setting.

METHODS

All adult (16+ years) acute inpatient MRCP requests for gallstone work-up between 1 Jan 2018 and 2031 Dec 2019 at Dunedin Hospital were included. Patients with characteristics not in fitting with an acute symptomatic examination were excluded. Receiver operating characteristic curves were estimated for bilirubin versus MRCP positive by the presence/absence of dilated ducts, indication and American Society of Gastrointestinal Endoscopy (ASGE) risk grouping.

RESULTS

A 106 patients were included. Mean bilirubin at presentation and time of MRCP, 47 versus 28 μmol/L, respectively. MRCP confirmed CDL in 39 (37%) patients. 38 (97%) had biochemical changes with choledocholithiasis. 21 (40%) with CBD dilation had ductal stones versus 18 (34%) with normal ducts. ASGE risk stratification showed 36 (34%), 66 (62%) and 4 (4%) were high, intermediate and low risk, respectively. Of these groups 44%, 35% and 0% had CBD stones on MRCP, respectively. Combination thresholds involving duct size and bilirubin can yield negative predictive values >90%, substantially reducing MRCP load.

CONCLUSIONS

MRCP requests can be triaged to maximize stones detected without overly increasing the rate of missed duct stones whilst protecting the limited MRI and ERCP resources. International thresholds and risk stratification alone may not be applicable in our resource limited environment.

Validation of choledocholithiasis predictors from the "2019 ASGE Guideline for the role of endoscopy in the evaluation and management of choledocholithiasis."

BACKGROUND AND AIMS

Identifying patients likely to have CDL is an important clinical dilemma because endoscopic retrograde cholangiopancreatography (ERCP), carries a 5-7% risk of adverse events. The purpose of this study was to compare the diagnostic test performance of the 2010 and 2019 ASGE criteria used to help risk stratify patients with suspected CDL.

METHODS

Consecutive patients evaluated for possible CDL from 2013 to 2019 were identified from surgical, endoscopic, and radiologic databases at a single academic center. Inclusion criteria included all patients who underwent ERCP and/or cholecystectomy with intraoperative cholangiogram (IOC) for suspected CDL. We calculated the diagnostic test performance of criteria from both guidelines and compared their discrimination using the receiver operator curve. Univariate and multivariate analysis was used to identify the strongest component predictors.

RESULTS

1098 patients [age 57.9 ± 19.0 years, 62.8% (690) F] were included. 66.3% (728) were found to have CDL on ERCP and/or IOC. When using the 2019 guidelines, the sensitivity, specificity, PPV, NPV, and accuracy are 65.8, 78.9, 86.3, 54.1, and 70.4%, respectively. Using the 2010 guidelines, the sensitivity, specificity, PPV, NPV, and accuracy are 50.5, 78.9, 82.5, 44.8, and 60.1%, respectively. The AUC for high-risk criteria using the 2019 guidelines [0.726 (0.695, 0.758)] was greater than for the 2010 guidelines [0.647 (0.614, 0.681)]. The key difference providing the increased discrimination was the inclusion of stones on any imaging modality, which increased the sensitivity to 55.0% from 29.1%. Not including CDL on imaging or cholangitis, a dilated CBD was the strongest individual predictor of CDL on multivariate analysis (OR 3.70, CI 2.80, 4.89).

CONCLUSION

Compared to 2010, the 2019 high-risk criterion improves diagnostic test performance, but still performs suboptimally. Less invasive tests, such as EUS or MRCP, should be considered in patients with suspected CDL prior to ERCP.

Cost-effectiveness analysis of optimal diagnostic strategy for patients with symptomatic cholelithiasis with intermediate probability for choledocholithiasis

BACKGROUND AND AIMS

EUS, MRCP, and intraoperative cholangiogram (IOC) are the recommended diagnostic modalities for patients with intermediate probability for choledocholithiasis (IPC). The relative cost-effectiveness of these modalities in patients with cholelithiasis and IPC is understudied.

METHODS

We developed a decision tree for diagnosing IPC (base-case probability, 50%; range, 10%-70%); patients with a positive test were modeled to undergo therapeutic ERCP. The strategies tested were laparoscopic cholecystectomy with IOC (LC-IOC), MRCP, single-session EUS + ERCP, and separate-session EUS + ERCP. Costs and probabilities were extracted from the published literature. Effectiveness was assessed by assigning utility scores to health states, average proportion of true-positive diagnosis of IPC, and the mean length of stay (LOS) per strategy. Cost-effectiveness was assessed by extrapolating a net-monetary benefit (NMB) and average cost per true-positive diagnosis.

RESULTS

LC-IOC was the most cost-effective strategy to diagnose IPC (base-case probability of 50%) among patients with cholelithiasis in health state-based effectiveness analysis (NMB of $34,612), diagnostic test accuracy-based effectiveness analysis (average cost of $13,260 per true-positive diagnosis), and LOS-based effectiveness analysis (mean LOS of 4.13) compared with strategies 2 (MRCP), 3 (single-session EUS + ERCP), and 4 (separate-session EUS + ERCP). These findings were robust on deterministic and probabilistic sensitivity analyses.

CONCLUSIONS

For patients with cholelithiasis with IPC, LC-IOC is a cost-effective approach that should limit preoperative testing and may shorten hospital LOS. Our findings may be used to design institutional and organizational management protocols.

Systematic review and meta-analysis of the 2010 ASGE non-invasive predictors of choledocholithiasis and comparison to the 2019 ASGE predictors

In 2019, the American Society for Gastrointestinal Endoscopy (ASGE) guideline on the endoscopic management of choledocholithiasis modified the individual predictors of choledocholithiasis proposed in the widely referenced 2010 guideline to improve predictive performance. Nevertheless, the primary literature, especially for the 2019 iteration, is limited. We performed a systematic review with meta-analysis to examine the diagnostic performance of the 2010, and where possible the 2019, predictors. PROSPERO protocol CRD42020194226. A comprehensive literature search from 2001 to 2020 was performed to identify studies on the diagnostic performance of any of the 2010 and 2019 ASGE choledocholithiasis predictors. Identified studies underwent keyword screening, abstract review, and full-text review. The primary outcomes included multivariate odds ratios (ORs) and 95% confidence intervals for each criterion. Secondary outcomes were reported sensitivities, specificities, and positive and negative predictive value. A total of 20 studies met inclusion criteria. Based on reported ORs, of the 2010 guideline “very strong” predictors, ultrasound with stone had the strongest performance. Of the “strong” predictors, CBD > 6 mm demonstrated the strongest performance. “Moderate” predictors had inconsistent and/or weak performance; moreover, all studies reported gallstone pancreatitis as non-predictive of choledocholithiasis. Only one study examined the new predictor (bilirubin > 4 mg/dL and CBD > 6 mm) proposed in the 2019 guideline. Based on this review, aside from CBD stone on ultrasound, there is discordance between the proposed strength of 2010 choledocholithiasis predictors and their published diagnostic performance. The 2019 guideline appears to do away with the weakest 2010 predictors.

Machine learning models compared to existing criteria for noninvasive prediction of endoscopic retrograde cholangiopancreatography-confirmed choledocholithiasis

BACKGROUND AND AIMS

Noninvasive predictors of choledocholithiasis have generally exhibited marginal performance characteristics. We aimed to identify noninvasive independent predictors of endoscopic retrograde cholangiopancreatography (ERCP)-confirmed choledocholithiasis and accordingly developed predictive machine learning models (MLMs).

METHODS

Clinical data of consecutive patients undergoing first-ever ERCP for suspected choledocholithiasis from 2015-2019 were abstracted from a prospectively-maintained database. Multiple logistic regression was used to identify predictors of ERCP-confirmed choledocholithiasis. MLMs were then trained to predict ERCP-confirmed choledocholithiasis using pre-ERCP ultrasound (US) imaging only and separately using all available noninvasive imaging (US/CT/magnetic resonance cholangiopancreatography). The diagnostic performance of American Society for Gastrointestinal Endoscopy (ASGE) "high-likelihood" criteria was compared to MLMs.

RESULTS

We identified 270 patients (mean age 46 years, 62.2% female, 73.7% Hispanic/Latino, 59% with noninvasive imaging positive for choledocholithiasis) with native papilla who underwent ERCP for suspected choledocholithiasis, of whom 230 (85.2%) were found to have ERCP-confirmed choledocholithiasis. Logistic regression identified choledocholithiasis on noninvasive imaging (odds ratio (OR) = 3.045, P = 0.004) and common bile duct (CBD) diameter on noninvasive imaging (OR=1.157, P = 0.011) as predictors of ERCP-confirmed choledocholithiasis. Among the various MLMs trained, the random forest-based MLM performed best; sensitivity was 61.4% and 77.3% and specificity was 100% and 75.0%, using US-only and using all available imaging, respectively. ASGE high-likelihood criteria demonstrated sensitivity of 90.9% and specificity of 25.0%; using cut-points achieving this specificity, MLMs achieved sensitivity up to 97.7%.

CONCLUSIONS

MLMs using age, sex, race, presence of diabetes, fever, body mass index (BMI), total bilirubin, maximum CBD diameter, and choledocholithiasis on pre-ERCP noninvasive imaging predict ERCP-confirmed choledocholithiasis with good sensitivity and specificity and outperform the ASGE criteria for patients with suspected choledocholithiasis.

Role of EUS at high risk for choledocholithiasis without severe cholangitis and visible stone on cross-sectional imaging: A multicenter randomized clinical trial

Background and Objectives:

The prevalence of choledocholithiasis in the high-risk group of choledocholithiasis has been reported to be slightly more than 50% when there is no definite cholangitis. Replacement of diagnostic endoscopic retrograde cholangiography (ERC) with an EUS-first approach may be beneficial in these patients.

Materials and Methods:

In this prospective, multicenter study, patients with dilated common bile duct and serum total bilirubin levels of 1.8–4 mg/dL were randomly allocated to undergo either EUS first, followed by subsequent ERC if necessary (EUS group) or ERC only (ERC group). The primary endpoint was the incidence of negative outcomes associated with a false-negative diagnosis of the choledocholithiasis or the endoscopic procedure. The secondary endpoints were the rate of diagnostic ERC and hospital stay length related to the endoscopic procedure.

Results:

Of 90 patients who were randomly assigned, the final analysis involved 42 in the EUS group and 44 in the ERC group. The negative outcomes were not significantly different between the EUS and ERC groups (2.4% vs. 6.8%; P = 0.62). The rate of diagnostic ERC was significantly lower in the EUS group (2.4% vs. 47.7%; P < 0.001). The hospital stay length related to the endoscopic procedure was significantly shorter in the EUS group (1.8 ± 1.0 vs. 2.5 ± 1.2 days; P = 0.001).

Conclusion:

In selected high-risk choledocholithiasis patients, an EUS-first strategy significantly decreased the rate of diagnostic ERC and hospital stay but did not achieve a significant reduction in negative endoscopic procedure outcomes.

Development of a risk score for choledocholithiasis in pediatric patients

PURPOSE

The prevalence of gallstones in children has increased over the last years. Choledocholithiasis (CD) is present in up to 30% of the cases. There is a scarcity of studies on the management of choledocholithiasis in children. The aim of this study was to develop a score that would allow predicting accurately the risk of CD in children with gallstones and reduce the number of non-therapeutic ERCP.

MATERIALS AND METHODS

We conducted a retrospective study in children with gallstones and suspected CD seen between January 2010 and December 2019. The main outcome was the presence of CD confirmed by at least one of the following diagnostic tests: magnetic resonance cholangiopancreatography (MRCP), endoscopic retrograde cholangiopancreatography (ERCP), and/or intraoperative cholangiography (IOC). We developed a risk score based on the presence or absence of the following risk factors: acute biliary pancreatitis, ascending cholangitis, elevated liver function tests (AST, ALT, total bilirubin [TB, ≥ 2 mg/dl], conjugated bilirubin, gamma-glutamyl transpeptidase, and alkaline phosphatase), CD on ultrasound (US; this was considered predictive but not confirmatory of CD), and dilation of the common bile duct (> 6 mm) by US. The score was divided into three different categories: low risk (no risk factors), intermediate risk (one risk factor present), high risk (≥ 2 risk factors present or ascending cholangitis). Given the main goal of reducing the number of diagnostic ERCPs, a very-high-risk subgroup (3 risk factors present or ascending cholangitis) was identified.

RESULTS

We reviewed 133 patients with gallstones and suspected CD. In 56 (42.1%) patients, the presence of CD was confirmed by one or more of the definitive diagnostic tests (MRCP, ERCP, and IOC). The following variables were found to be the strongest predictors of CD: ascending cholangitis, TB ≥ 2 mg/dl, common bile duct > 6 mm, and the presence of CD by US. The positive predictive value for CD was 7.5% in the low-risk group (OR 0.06, P = < 0.001); 22.9% in the intermediate-risk group (OR 0.31, P = 0.007); 77.6% in the high-risk group (OR 20.14, P = < 0.001); and 95.7% in very-high-risk subgroup (OR 49.18, P = < 0.001).

CONCLUSION

The risk score proposed in this study predicts accurately the presence of CD in children with gallstones. It can serve as a helpful tool to triage the need for costly and complex studies in the workup of CD, particularly in centers with limited resources. Finally, due to its high specificity and positive predictive value (PPV), the use of the very-high-risk criteria would allow for an important decrease in the number of non-therapeutic ERCP.

Choledocholithiasis-a new clinical pathway

The incidence of cholecystectomy in children has increased considerably since the early 1990s. Management of gallbladder disease in children must include an awareness of choledocholithiasis treatment strategies. Both endoscopic retrograde cholangiopancreatography (ERCP) and common bile duct exploration (open or laparoscopic) are accepted management techniques for choledocholithiasis. Laparoscopic cholecystectomy with preoperative or postoperative ERCP is at least a two-procedure process while cholecystectomy with laparoscopic common bile duct exploration (LCBDE) can provide definitive treatment in a single procedure under one anesthetic. Despite this, the trend over the last decade continues towards less LCBDE utilization in favor of ERCP. This trend has resulted in decreased familiarity with LCBDE by adult and pediatric surgeons and their trainees. Access to the necessary tools and education on the technical aspects can allow for successful single-stage treatment of choledocholithiasis by surgeons during laparoscopic cholecystectomy. This may include a pre-defined stepwise algorithm and understanding of all the equipment and resources necessary to perform a LCBDE. Ultimately, increased understanding of the equipment and procedural steps necessary for LCBDE will result in widened adoption of the technique and thus confer advantages to the patient such as decreased length of stay and fewer required anesthetics.

A prospective multicenter analysis from the Pediatric ERCP Database Initiative: predictors of choledocholithiasis at ERCP in pediatric patients

BACKGROUND AND AIMS

The management of suspected choledocholithiasis remains a challenge in pediatric endoscopy. Several recommendations are available for adult patients; however, it is unknown which pediatric patients are most likely to benefit from ERCP for evaluation of choledocholithiasis. The primary aim of this study was to evaluate adult-based criteria in the evaluation of pediatric patients with choledocholithiasis. A secondary aim was to evaluate the role of conjugated (or direct) bilirubin to improve the sensitivity of detecting choledocholithiasis.

METHODS

This was a prospective multicenter study in pediatric patients as part of the Pediatric ERCP Database Initiative (PEDI) with additional post-hoc analysis of updated guidelines. Patients <19 years of age undergoing ERCP for suspected choledocholithiasis or gallstone pancreatitis were enrolled at participating sites.

RESULTS

Ninety-five patients were enrolled (69 with choledocholithiasis confirmed at ERCP and 26 with no stones at ERCP). Adverse event rates were similar in both groups. Specificity ranged from 27% to 91% using adult guidelines, but a sensitivity of only 20% to 69%. The were no significant differences between the 2 groups using preprocedure transabdominal US (P = 1.0). Significant differences between groups were identified using either the total or conjugated bilirubin (P = .02). There was also a significant difference between the stone and no-stone groups when conjugated bilirubin was dichotomized to >2 mg/dL (P = .03).

CONCLUSIONS

Abdominal imaging and laboratory indices may be used to predict pediatric choledocholithiasis with varying sensitivity and specificity. Pediatric-specific guidelines may allow for improved stone prediction compared with existing adult recommendations.

Comparing diagnostic accuracy of current practice guidelines in predicting choledocholithiasis: outcomes from a large healthcare system comprising both academic and community settings

BACKGROUND AND AIMS

The American Society for Gastrointestinal Endoscopy (ASGE) 2010 guidelines for suspected choledocholithiasis were recently updated by proposing more specific criteria for selection of high-risk patients to undergo direct ERCP while advocating the use of additional imaging studies for intermediate- and low-risk individuals. We aim to compare the performance and diagnostic accuracy of 2019 versus 2010 ASGE criteria for suspected choledocholithiasis.

METHODS

We performed a retrospective chart review of a prospectively maintained database (2013-2019) of over 10,000 ERCPs performed by 70 gastroenterologists in our 14-hospital system. We randomly selected 744 ERCPs in which the primary indication was suspected choledocholithiasis. Patients with a history of cholecystectomy or prior sphincterotomy were excluded. The same patient cohort was assigned as low, intermediate, or high risk according to the 2010 and 2019 guideline criteria. Overall accuracy of both guidelines was compared against the presence of stones and/or sludge on ERCP.

RESULTS

Of 744 patients who underwent ERCP, 544 patients (73.1%) had definite stones during ERCP and 696 patients (93.5%) had stones and/or sludge during ERCP. When classified according to the 2019 guidelines, fewer patients were high risk (274/744, 36.8%) compared with 2010 guidelines (449/744, 60.4%; P < .001). Within the high-risk group per both guidelines, definitive stone was found during ERCP more frequently in the 2019 guideline cohort (226/274, 82.5%) compared with the 2010 guideline cohort (342/449, 76.2%; P < .001). In our patient cohort, overall specificity of the 2010 guideline was 46.5%, which improved to 76.0% as per 2019 guideline criteria (P < .001). However, no significant change was noted for either positive predictive value or negative predictive value between 2019 and 2010 guidelines.

CONCLUSIONS

The 2019 ASGE guidelines are more specific for detection of choledocholithiasis during ERCP when compared with the 2010 guidelines. However, a large number of patients are categorized as intermediate risk per 2019 guidelines and will require an additional confirmatory imaging study.

The Role of Transaminases in Predicting Choledocholithiasis. A Novel Predictive Composite Score Development in a Cohort of 1089 Patients Undergoing Laparoscopic Cholecystectomy

BACKGROUND

Optimal use of interventional procedures and diagnostic tests for patients with suspected choledocholithiasis depends on accurate pretest risk estimation. We sought to define sensitivity/specificity of transaminases in identifying choledocholithiasis and to incorporate them into a biochemical marker composite score that could accurately predict choledocholithiasis.

METHODS

All adult patients who underwent laparoscopic cholecystectomy by our Emergency Surgery Service between 2010 and 2018 were reviewed. Admission total bilirubin (TB), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) was captured. Choledocholithiasis was confirmed via intraoperative cholangiogram, endoscopic retrograde cholangiopancreatography, or magnetic resonance cholangiopancreatography. Area under receiver operating characteristic curve (AUC) or C-statistic for AST, ALT, ALP, and TB as a measure of detecting choledocholithiasis was calculated. For score development, our database was randomly dichotomized to derivation and validation cohort and a score was derived. The score was validated by calculating its C-statistic.

RESULTS

1089 patients were included; 210 (20.3%) had confirmed choledocholithiasis. The AUC was .78 for TB, .77 for ALP and AST, and .76 for ALT. 545 and 544 patients were included in the derivation and the validation cohort, respectively. The elements of the derived score were TB, AST, and ALP. The score ranged from 0 to 4. The AUC was .82 in the derivation and .77 in the validation cohort. The probability of choledocholithiasis increased from 8% to 89% at scores 0 to 4, respectively.

CONCLUSIONS

Aspartate aminotransferase predicted choledocholithiasis adequately and should be featured in choledocholithiasis screening algorithms. We developed a biochemical composite score, shown to be accurate in preoperative choledocholithiasis risk assessment in an emergency surgery setting.

Comparison of Endoscopy First and Laparoscopic Cholecystectomy First Strategies for Patients With Gallstone Disease and Intermediate Risk of Choledocholithiasis: Protocol for a Clinical Randomized Controlled Trial

Background

The optimal approach for patients with gallbladder stones and intermediate risk of choledocholithiasis remains undetermined. The use of endoscopic retrograde cholangiopancreatography for diagnosis should be minimized as it carries considerable risk of postprocedural complications, and nowadays, less invasive and safer techniques are available.

Objective

This study compares the two management strategies of endoscopic ultrasound before laparoscopic cholecystectomy and intraoperative cholangiography for patients with symptomatic cholecystolithiasis and intermediate risk of choledocholithiasis.

Methods

This is a randomized, active-controlled, single-center clinical trial enrolling adult patients undergoing laparoscopic cholecystectomy for symptomatic gallbladder stones with intermediate risk of choledocholithiasis. The risk of choledocholithiasis is calculated using an original prognostic score (the Vilnius University Hospital Index). This index in a retrospective evaluation showed better prognostic performance than the score proposed by the American Society for Gastrointestinal Endoscopy in 2010. A total of 106 participants will be included and randomized into two groups. Evaluation of bile ducts using endoscopic ultrasound and endoscopic retrograde cholangiography on demand will be performed before laparoscopic cholecystectomy for one arm (“endoscopy first”). Intraoperative cholangiography during laparoscopic cholecystectomy and postoperative endoscopic retrograde cholangiopancreatography on demand will be performed in another arm (“cholecystectomy first”). Postoperative follow-up is 6 months. The primary endpoint is the length of hospital stay. The secondary endpoints are accuracy of the different management strategies, adverse events of the interventions, duct clearance and technical success of the interventions (intraoperative cholangiography, endoscopic ultrasound, and endoscopic retrograde cholangiography), and cost of treatment.

Results

The trial protocol was approved by the Vilnius Regional Biomedical Research Ethics Committee in December 2017. Enrollment of patients was started in January 2018. As of June 2020, 66 patients have been enrolled.

Conclusions

This trial is planned to determine the superior strategy for patients with intermediate risk of common bile duct stones and to define a simple and safe algorithm for managing choledocholithiasis.

Trial Registration

ClinicalTrials.gov NCT03658863; https://clinicaltrials.gov/ct2/show/NCT03658863.

International Registered Report Identifier (IRRID)

DERR1-10.2196/18837

Artificial intelligence in pancreaticobiliary endoscopy

Artificial intelligence (AI) applications in health care have exponentially increased in recent years, and a few of these are related to pancreatobiliary disorders. AI-based methods were applied to extract information, in prognostication, to guide clinical treatment decisions and in pancreatobiliary endoscopy to characterize lesions. AI applications in endoscopy are expected to reduce inter-operator variability, improve the accuracy of diagnosis, and assist in therapeutic decision-making in real time. AI-based literature must however be interpreted with caution given the limited external validation. A multidisciplinary approach combining clinical and imaging or endoscopy data will better utilize AI-based technologies to further improve patient care.

The Challenges of Implementing Artificial Intelligence into Surgical Practice

BACKGROUND

Artificial intelligence is touted as the future of medicine. Classical algorithms for the detection of common bile duct stones (CBD) have had poor clinical uptake due to low accuracy. This study explores the challenges of developing and implementing a machine-learning model for the prediction of CBD stones in patients presenting with acute biliary disease (ABD).

METHODS

All patients presenting acutely to Christchurch Hospital over a two-year period with ABD were retrospectively identified. Clinical data points including lab test results, demographics and ethnicity were recorded. Several statistical techniques were utilised to develop a machine-learning model. Issues with data collection, quality, interpretation and barriers to implementation were identified and highlighted.

RESULTS

Issues with patient identification, coding accuracy, and implementation were encountered. In total, 1315 patients met inclusion criteria. Incorrect international classification of disease 10 (ICD-10) coding was noted in 36% (137/382) of patients recorded as having CBD stones. Patients with CBD stones were significantly older and had higher aspartate aminotransferase (AST), alanine aminotransferase (ALT), bilirubin and gamma-glutamyl transferase (GGT) levels (p < 0.001). The no information rate was 81% (1070/1315 patients). The optimum model developed was the gradient boosted model with a PPV of 67%, NPV of 87%, sensitivity of 37% and a specificity of 96% for common bile duct stones.

CONCLUSION

This paper highlights the utility of machine learning in predicting CBD stones. Accuracy is limited by current data and issues do exist around both the ethics and practicality of implementation. Regardless, machine learning represents a promising new paradigm for surgical practice.

A validated score predicting common bile duct stone in patients hospitalized with acute calculus cholecystitis: a multi-center retrospective study

BACKGROUND

Concomitant common bile duct (CBD) stone in the setting of acute calculous cholecystitis (ACC) should be suspected once abnormal liver indices are noticed.

AIM

We aimed to identify predictors of CBD stone in patients hospitalized with ACC.

METHODS

We performed a retrospective multi-center, case-controlled, study from 1st of January 2016 until the 31th of December 2018. Inclusion criteria included patients with an established diagnosis of ACC based on clinical, laboratory and radiological criteria and who had an endoscopic ultrasound (EUS) for suspected CBD stone. One-hundred and twelve patients were included, of these fifty-three patients (47.3%) were diagnosed with CBD stone by EUS.

RESULTS

In univariate analysis, Age (OR 1.038, P = 0.001), total bilirubin (mg/dl) (OR 1.429, P = 0.02) and CBD width (mm) by US (OR 1.314, P = 0.01) were statistically significant in predicting CBD stone and remained significant in multivariate regression analysis. We developed a diagnostic score that included these three parameters, with assignment of weights for each variable according to the coefficient estimate. A low cut-off score of 0 was associated with sensitivity of 100% for CBD stone, whereas a high cut-off score of 3 was associated with sensitivity of 10% and specificity of 96.6% with a positive predictive value of 67% (ROC of 0.7558). We validated this score with an independent cohort (ROC of 0.7416) with a sensitivity of 46.6%, a specificity of 91.5% and a PPV of 87.1%.

CONCLUSION

We recommend incorporating this score as an aid for stratifying patients with ACC into low or high probability for concomitant CBD stone.

Predicting common bile duct stones by non-invasive parameters

BACKGROUND

Common bile duct (CBD) stone affect about 10% of patients with symptomatic cholelithiasis. The American Society for Gastrointestinal Endoscopy (ASGE) published a strategy in 2010 for managing patients with suspected choledocholithiasis. This study aimed to assess the performance of different clinical parameters in predicting CBD stones.

METHODS

A total of 344 patients suspected to suffer from CBD stone and referred to endoscopic ultrasound (EUS) were included. Parameters were collected and their prediction power for CBD stones was assessed.

RESULTS

One hundred and sixty-seven patients without CBD stone according to EUS (group A) were compared to 177 patients with CBD stones (group B). Several predictive factors for CBD stone were identified on univariate analysis. In multivariate regression analysis, CBD width by US (OR = 1.224, 95% CI: 1.073-1.359; P = 0.0026), age (OR = 1.023, 95% CI: 1.011-1.035; P = 0.0002) and gamma glutamyl transferase (GGT) level (OR = 1.001, 95% CI: 1.000-1.002; P = 0.0018) were significantly correlated with CBD stone, with receiver operator characteristics (ROC) of 0.7259. We generated a diagnostic equation [age (yr) × 0.1 + CBD width (mm) by US × 1 + GGT (U/L) × 0.005] to predict CBD stone with ROC of 0.7287.

CONCLUSIONS

We suggest this score as a very strong predictor for CBD stones, and to reduce the strength of total bilirubin and transaminases as predictors.

Diagnostic performance of the current risk-stratified approach with computed tomography for suspected choledocholithiasis and its options when negative finding

BACKGROUND

Several studies evaluated the current guideline of the American Society for Gastrointestinal Endoscopy (ASGE) and reported only suboptimal accuracy. This study evaluated the diagnostic performance of the ASGE guideline based on computed tomography (CT) and role of endoscopic ultrasonography (EUS) and magnetic resonance cholangiopancreatography (MRCP) in patients with suspected choledocholithiasis but negative CT finding.

METHODS

Patients with suspected choledocholithiasis undergoing ERCP between January 2016 and January 2017 were retrospectively analyzed. All patients underwent CT to detect choledocholithiasis. EUS or MRCP was performed when the CT scan showed negative findings. Patients were classified into the high and intermediate-risk groups, based on predictors from the ASGE criteria.

RESULTS

Of 583 patients with suspected choledocholithiasis, 340 (58.3%) had stones on ERCP (65.9% in the high-risk group and 40.6% in the intermediate-risk group). The accuracy of ASGE guideline for CT was 63.98% (79.12% sensitivity, 42.80% specificity) and 36.02% (20.88% sensitivity, 57.20% specificity) in the high-risk and intermediate-risk groups, respectively. In 103 patients in the high-risk group underwent both CT and US, the accuracy of CT was higher than that of US for detecting choledocholithiasis (78.64% vs. 53.40%), with a significant difference in area under the curve (AUC) (0.78 vs. 0.59, P < 0.001). Of 339 with negative CT finding, the accuracy of EUS was higher than that of MRCP (90.91% vs. 82.76%), but with no significant difference in AUC (0.91 vs. 0.83, P = 0.347).

CONCLUSIONS

CT-based ASGE guideline showed superior diagnostic performance than US for predicting choledocholithiasis. The diagnostic options, EUS or MRCP, with negative CT finding showed comparable performance. Therefore, the diagnostic modality should be selected based on availability, experience, cost, and contraindications.

ASGE guideline on the role of endoscopy in the evaluation and management of choledocholithiasis

Each year choledocholithiasis results in biliary obstruction, cholangitis, and pancreatitis in a significant number of patients. The primary treatment, ERCP, is minimally invasive but associated with adverse events in 6% to 15%. This American Society for Gastrointestinal Endoscopy (ASGE) Standard of Practice (SOP) Guideline provides evidence-based recommendations for the endoscopic evaluation and treatment of choledocholithiasis. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework was used to rigorously review and synthesize the contemporary literature regarding the following topics: EUS versus MRCP for diagnosis, the role of early ERCP in gallstone pancreatitis, endoscopic papillary dilation after sphincterotomy versus sphincterotomy alone for large bile duct stones, and impact of ERCP-guided intraductal therapy for large and difficult choledocholithiasis. Comprehensive systematic reviews were also performed to assess the following: same-admission cholecystectomy for gallstone pancreatitis, clinical predictors of choledocholithiasis, optimal timing of ERCP vis-à-vis cholecystectomy, management of Mirizzi syndrome and hepatolithiasis, and biliary stent therapy for choledocholithiasis. Core clinical questions were derived using an iterative process by the ASGE SOP Committee. This body developed all recommendations founded on the certainty of the evidence, balance of risks and harms, consideration of stakeholder preferences, resource utilization, and cost-effectiveness.

Dynamic liver test patterns do not predict bile duct stones

BACKGROUND

Numerous models have been developed to predict choledocholithiasis. Recent work has shown that these algorithms perform suboptimally. Identification of clinical predictors with high positive and negative predictive value would minimize adverse events associated with unnecessary diagnostic endoscopic retrograde cholangiopancreatography (ERCP) while limiting the use of expensive tests including magnetic resonance cholangiopancreatography (MRCP) and endoscopic ultrasound (EUS) for indeterminate cases.

METHODS

Consecutive unique inpatients who received their first ERCP at Los Angeles County Medical Center between January 2010 and November 2016 for suspected bile duct stones were reviewed. The primary outcome was the proportion of patients with specific combinations of liver enzyme patterns, transabdominal ultrasound, and clinical features who had stones confirmed on ERCP. As a secondary outcome, we assessed the performance of the American Society for Gastrointestinal Endoscopy (ASGE) risk stratification algorithm in our population.

RESULTS

Of the 604 included patients, bile duct stones were confirmed in 410 (67.9%). Detailed assessment of liver enzyme patterns alone and in combination with clinical features and imaging findings yielded no highly predictive algorithms. Additionally, the ASGE high-risk criterion had a positive predictive value of only 68% for stones. For the 236 patients for whom MRCP was performed, this imaging modality was shown to have highest predictive value for the presence of stones on ERCP.

CONCLUSION

Exhaustive exploration of various threshold values and dynamic patterns of liver enzymes combined with clinical features and basic imaging findings did not reveal an algorithm to accurately predict the presence of stones on ERCP. The ASGE risk stratification criteria were also insensitive in our population. Though desirable, there may be no "perfect" combination of clinical features that correlate with persistent bile duct stones. MRCP or EUS may be considered to avoid unnecessary ERCP and associated complications.

ASGE high-risk criteria for choledocholithiasis - Are they applicable in cholecystectomized patients?

BACKGROUND AND AIMS

The guidelines by the American Society for Gastrointestinal Endoscopy (ASGE) suggest that in patients with gallbladder in situ, endoscopic retrograde cholangiopancreatography (ERCP) should be performed in the presence of high-risk criteria for choledocholithiasis, after biochemical tests and abdominal ultrasound. There are no specific recommendations for cholecystectomized patients. The aim of this study was to evaluate the applicability of ASGE criteria for ERCP in cholecystectomized patients with suspected choledocholithiasis.

METHODS

We conducted a retrospective study that included patients with high-risk ASGE criteria for choledocholithiasis who underwent ERCP from 2013-2016.

RESULTS

We included 327 patients in our analysis - 258 with gallbladder in situ (79%) and 69 with cholecystectomy (21%). We showed that the ASGE criteria true positive rate was similar between patients with and without cholecystectomy - the prevalence of choledocholithiasis on ERCP was 71% in cholecystectomized and 70% in non-cholecystectomized. In addition, both the presence and the diameter of the CBD stone were predictors of positive ERCP in both groups. In contrast, the diameter of the CBD was predictor of positive ERCP only in non-cholecystectomized patients.

CONCLUSIONS

Although dilatation of the CBD was not a predictive factor for choledocholithiasis in cholecystectomized patients, the ASGE criteria true positive rate was similar to that of non-cholecystectomized patients.

Current clinical algorithms for predicting common bile duct stones have only moderate accuracy

BACKGROUND AND AIM

A risk-stratified approach for selecting patients likely to harbor common bile duct (CBD) stones to proceed directly to endoscopic or surgical stone clearance, rather than undergo less invasive testing, has been proposed. We assessed the performance of three clinical algorithms used to predict CBD stones.

METHODS

All patients undergoing first-time endoscopic retrograde cholangiopancreatography (ERCP) in 2011-2012 as a result of suspected CBD stones were enrolled prospectively in a clinical database. Data such as imaging test findings and liver function tests (LFTs) were collected 48 h prior to and on the day of ERCP. Patients were stratified into different risk groups for harboring CBD stones according to three clinical algorithms using imaging and laboratory data. Findings on ERCP were used as gold standard. Performance characteristics of each algorithm were separately calculated for each time point of LFT assessment.

RESULTS

Overall, 186 patients were analyzed, 75% of whom presented CBD stones on ERCP. Proportion of patients categorized as high-risk for harboring CBD stones varied among the three algorithms (67% vs 73% vs 56%). Also, the algorithms showed only moderate, albeit comparable, accuracy for predicting the presence of CBD stones (0.65, 95% confidence interval [CI] 0.62-0.68 vs 0.68, 95% CI 0.63-0.67 vs 0.59, 95% CI 0.57-0.61). Similar results were obtained when performance characteristics were recalculated using LFT from 48 h prior to ERCP (data not shown).

CONCLUSION

Three diagnostic algorithms commonly used for predicting CBD stones have comparable but only moderate accuracy. Further research is warranted to improve risk stratification of patients with suspected CBD stones.

New classification system for indications for endoscopic retrograde cholangiopancreatography predicts diagnoses and adverse events

BACKGROUND

Indications for endoscopic retrograde cholangiopancreatography (ERCP) have received little attention, especially in scientific or objective terms.

AIM

To review the prevailing ERCP indications in the literature, and to propose and evaluate a new ERCP indication system, which relies on more objective pre-procedure parameters.

METHODS

An analysis was conducted on 1758 consecutive ERCP procedures, in which contemporaneous use was made of an a-priori indication system. Indications were based on the objective pre-procedure parameters and divided into primary [cholangitis, clinical evidence of biliary leak, acute (biliary) pancreatitis, abnormal intraoperative cholangiogram (IOC), or change/removal of stent for benign/malignant disease] and secondary [combination of two or three of: pain attributable to biliary disease ('P'), imaging evidence of biliary disease ('I'), and abnormal liver function tests (LFTs) ('L')]. A secondary indication was only used if a primary indication was not present. The relationship between this newly developed classification system and ERCP findings and adverse events was examined.

RESULTS

The indications of cholangitis and positive IOC were predictive of choledocholithiasis at ERCP (101/154 and 74/141 procedures, respectively). With respect to secondary indications, only if all three of 'P', 'I', and 'L' were present there was a statistically significant association with choledocholithiasis (χ²(1) = 35.3, p < .001). Adverse events were associated with an unusual indication leading to greater risk of unplanned hospitalization (χ²(1) = 17.0, p < .001).

CONCLUSIONS

An a-priori-based indication system for ERCP, which relies on pre-ERCP objective parameters, provides a more useful and scientific classification system than is available currently.

Risk assessment of choledocholithiasis prior to laparoscopic cholecystectomy and its management options

Background

Accurate risk evaluation of choledocholithiasis prior to laparoscopic cholecystectomy is essential to determine optimal management strategy.

Objective

Our study aimed to evaluate the accuracy of separate predictors and Vilnius University Hospital Index (VUHI = A/30 + 0.4 × B; A = total bilirubin concentration (µmol/l), B = common bile duct (CBD) diameter (mm) measured by ultrasound) diagnosing choledocholithiasis and to assess different management strategies (cholecystectomy with intraoperative cholangiography and endoscopic retrograde cholangiopancreatography (ERCP)).

Methods

The retrospective study included 350 patients admitted to a tertiary care centre for laparoscopic cholecystectomy for cholecystolithiasis who were investigated for concomitant choledocholithiasis.

Results

Choledocholithiasis was diagnosed in 182 (76.2%) cases in the high-risk group (VUHI value ≥4.7) and 44 (39.6%) in the low, odds ratio is 4.86 (95% CI: 3.00-7.88). Its sensitivity was 80.5%, specificity 54.0%, accuracy 71.1%. Dilated CBD had the highest sensitivity (92.5%) of predictors.ERCP showed better diagnostic performance than intraoperative cholangiography. Complications of ERCP were more frequent for patients without stones. There was no significant difference of outcomes between the two management strategies.

Conclusion

The prognostic index has good diagnostic accuracy but dividing patients into two risk groups is insufficient. The suggested model allows determining an intermediate-risk group, which requires additional investigation. Both management approaches are appropriate.

Accuracy of ASGE high-risk criteria in evaluation of patients with suspected common bile duct stones

BACKGROUND AND AIMS

ERCP is recommended for patients considered high risk for choledocholithiasis after biochemical testing and abdominal US. Our aim was to determine whether the American Society for Gastrointestinal Endoscopy (ASGE) guidelines accurately select patients for whom the risk of ERCP is justified.

METHODS

Consecutive patients hospitalized with suspected choledocholithiasis at Sir Run Run Shaw Hospital who received biochemical testing, abdominal US, and definitive testing for choledocholithiasis (MRCP, EUS, ERCP, intraoperative cholangiogram, and/or common bile duct [CBD] exploration) were identified. Patients with choledocholithiasis on abdominal US, with bilirubin levels >4 mg/dL (normal values <1.2 mg/dL), bilirubin levels ≥1.8 mg/dL plus a dilated CBD and/or clinical cholangitis were considered high risk per ASGE guidelines.

RESULTS

Of 2724 patients with suspected choledocholithiasis, 1171 (43%) met high-risk criteria. Definitive testing (MRCP in 2442 [90%], EUS in 67 [2%], ERCP in 659 [24%], intraoperative cholangiogram in 229 [8%], and CBD exploration in 447 [16%]) revealed choledocholithiasis in 1076 [40%] patients. The specificity of the ASGE high-risk criteria was 74% (95% confidence interval [CI], 72%-77%) and positive predictive value was 64% (95% CI, 61%-67%). Using a more restrictive criteria (choledocholithiasis on abdominal US, bilirubin >4 mg/dL plus dilated CBD) improved the specificity to 94% (95% CI, 93%-95%) and positive predictive value to 85% (95% CI, 82%-88%). Doubling or more of bilirubin to >4 mg/dL and ≥1.8 mg/dL at second testing had specificities of 98% (95% CI, 96%-99%) and 95% (95% CI, 93%-96%), with positive predictive values of 62% (95% CI, 48%-76%) and 54% (95% CI, 44%-65%), respectively.

CONCLUSIONS

Although ASGE high-risk criteria demonstrated >50% probability of the patient having choledocholithiasis, more than a third of the patients would receive diagnostic ERCPs. Criteria with choledocholithiasis on abdominal US and/or bilirubin levels >4 mg/dL plus a dilated CBD showed higher specificity and positive predictive value.