Prediction of therapy in primary endoscopic retrograde cholangiopancreatography

Development of a Predictive Model for Common Bile Duct Stones in Patients With Clinical Suspicion of Choledocholithiasis: A Cohort Study

BACKGROUND

Current choledocholithiasis guidelines heavily focus on patients with low or no risk, they may be inappropriate for populations with high rates of choledocholithiasis. We aimed to develop a predictive scoring model for choledocholithiasis in patients with relevant clinical manifestations.

METHODS

A multivariable predictive model development study based on a retrospective cohort of patients with clinical suspicion of choledocholithiasis was used in this study. The setting was a 700-bed public tertiary hospital. Participants were patients who had completed three reference tests (endoscopic retrograde cholangiography, magnetic resonance cholangiopancreatography, and intraoperative cholangiography) from January 2019 to June 2021. The model was developed using logistic regression analysis. Predictor selection was conducted using a backward stepwise approach. Three risk groups were considered. Model performance was evaluated by area under the receiver operating characteristic curve, calibration, classification measures, and decision curve analyses.

RESULTS

Six hundred twenty-one patients were included; the choledocholithiasis prevalence was 59.9%. The predictors were age > 55 years, pancreatitis, cholangitis, cirrhosis, alkaline phosphatase level of 125 - 250 or > 250 U/L, total bilirubin level > 4 mg/dL, common bile duct size > 6 mm, and common bile duct stone detection. Pancreatitis and cirrhosis each had a negative score. The sum of scores was -4.5 to 28.5. Patients were categorized into three risk groups: low-intermediate (score ≤ 5), intermediate (score 5.5 - 14.5), and high (score ≥ 15). Positive likelihood ratios were 0.16 and 3.47 in the low-intermediate and high-risk groups, respectively. The model had an area under the receiver operating characteristic curve of 0.80 (95% confidence interval: 0.76, 0.83) and was well-calibrated; it exhibited better statistical suitability to the high-prevalence population, compared to current guidelines.

CONCLUSIONS

Our scoring model had good predictive ability for choledocholithiasis in patients with relevant clinical manifestations. Consideration of other factors is necessary for clinical application, particularly regarding the availability of expert physicians and specialized equipment.

How to measure quality in endoscopic retrograde cholangiopancreatography (ERCP)

Endoscopic retrograde cholangiopancreatography (ERCP) is invasive therapeutic procedure demanding specific individual approach for learning and mastering. It is associated with greater morbidity and mortality than any other procedure in gastroenterology. The risk for complications and harm for patient inevitably require strict guidelines to be followed regarding training, certification and proficiency. In an attempt to reduce the risk of complications, various endoscopic societies worldwide have established so called "Quality measures" which proved to be the back bone for safety and quality in ERCP. Recently developed ERCP quality network allowing data comparison between endoscopist is the key of reducing complications and creating a state of the art teaching program for beginner endoscopist. Further research is required regarding quality measures improvement and information exchange in the global ERCP quality network.

Updated guideline on the management of common bile duct stones (CBDS)

Common bile duct stones (CBDS) are estimated to be present in 10-20% of individuals with symptomatic gallstones. They can result in a number of health problems, including pain, jaundice, infection and acute pancreatitis. A variety of imaging modalities can be employed to identify the condition, while management of confirmed cases of CBDS may involve endoscopic retrograde cholangiopancreatography, surgery and radiological methods of stone extraction. Clinicians are therefore confronted with a number of potentially valid options to diagnose and treat individuals with suspected CBDS. The British Society of Gastroenterology first published a guideline on the management of CBDS in 2008. Since then a number of developments in management have occurred along with further systematic reviews of the available evidence. The following recommendations reflect these changes and provide updated guidance to healthcare professionals who are involved in the care of adult patients with suspected or proven CBDS. It is not a protocol and the recommendations contained within should not replace individual clinical judgement.

Serology and ultrasound for diagnosis of choledocholithiasis

INTRODUCTION

Magnetic resonance cholangiopancreatography (MRCP) is not a routine investigation to exclude choledocholithiasis unless there is clinical or biochemical suspicion of common bile duct (CBD) stones. This study attempted to determine which radiological or serological parameters best predicted CBD stones.

METHODS

All patients undergoing MRCP from 2005 to 2011 were selected. Patients with pancreatitis were excluded. Liver function tests (LFTs) at admission and prior to MRCP were recorded, as was abdominal ultrasonography and MRCP results. Parameters measured routinely on LFTs included alkaline phosphatase (ALP), alanine transaminase (ALT) and bilirubin. Receiver operating characteristic curve area analysis (area under the curve [AUC]) and chi-squared analysis were undertaken.

RESULTS

Overall, 195 patients were identified, 71 of whom had CBD stones on MRCP. Raised ALP levels on admission demonstrated a correlation with CBD stones (AUC: 0.619, odds ratio [OR]: 3.16, p=0.06). At ultrasonography, a dilated CBD (OR: 3.76, p<0.001) and intrahepatic duct dilation (OR: 5.56, p<0.001) were highly significant predictors. However, only 37% of patients had a dilated CBD on ultrasonography. Ongoing elevation of LFT parameters, particularly ALP (AUC: 0.707, OR: 4.64, p<0.001) and ALT (AUC: 0.646, OR: 5.40, p<0.001), displayed a significant correlation with CBD stones.

CONCLUSIONS

Ongoing (even if minor) elevations of liver function test parameters should prompt the need to exclude CBD stones even in the presence of a normal CBD diameter on ultrasonography.

Appropriate patient selection in the management of common bile duct stones: when not to do ERCP

Background. Magnetic resonance cholangiopancreatography (MRCP) is noninvasive and accurate for diagnosing intra common bile duct stones (ICSs). However, given limited access, routine utilisation for investigating all patients with gallstone disease is neither practical nor cost-effective. Conversely, many individuals proceed directly to endoscopic retrograde cholangiopancreatography (ERCP), an invasive test with appreciable complications. Aim. Identify factors associated with ICS in order to improve risk-stratification for MRCP/ERCP. Methods. All patients having undergone cholecystectomy between November 2007 and October 2008 were reviewed. High-risk features for ICS were predefined, and their true presence confirmed by ERCP or intraoperative cholangiogram. Multivariate logistic regression was performed on candidate risk features. Results. Of 231 patients, 10.4% had ICS. Defining a high-risk group with "both" biochemical and ultrasound risk factors predicted ICS with 92% specificity and also bore strong association (OR 8.88). However, isolated hyperbilirubinaemia, ultrasound impression of CBD stones, and clinical risk factors did not (OR 1.10, 0.97, and 1.26). Normal liver biochemistry and normal ultrasound had a NPV of 99.5% for ICS. Conclusions. Ultrasound impression of CBD calculi without ductal dilatation is not predictive of ICS. Patients with normal liver biochemistry and normal CBD diameter on ultrasound are unlikely to have ICS and should not proceed to ERCP.

Biliary, pancreatic, and hepatic imaging for the general surgeon

Technologic advancements have allowed imaging modalities to become more useful in the diagnosis of hepatobiliary and pancreatic disorders. Computed tomography scanners now use multidetector row technology with contrast-delayed imaging for quicker and more accurate imaging. Magnetic resonance imaging with cholangiopancreatography can more clearly delineate liver lesions and the biliary and pancreatic ducts, and can diagnose pathologic conditions early in their course. Newer technologies, such as single-operator cholangioscopy and endoscopic ultrasonography, have sometimes shown superiority to traditional modalities. This article addresses the literature regarding available imaging techniques in the diagnosis and treatment of common surgical hepatobiliary and pancreatic diseases.

pERCePtions on ERCP utilization in the United States

Endoscopic retrograde cholangiopancreatography (ERCP), once a popular modality for diagnosing biliary tract and pancreatic disease, has passed its peak utilization. In the current issue of AJG, Jamal and colleagues summarize the trends in ERCP utilization in the United States from 1988 to 2002. While ERCP utilization had increased among certain ethnic groups, its overall use has dropped considerably since 1996. In particular, they report that the use of ERCP as a diagnostic tool and in the outpatient setting has declined. The introduction of less invasive pancreaticobiliary imaging tools, namely, endoscopic ultrasound (EUS) and magnetic resonance cholangiopancreatography (MRCP), is likely responsible for this trend. However, ERCP is still used widely and appropriately in the therapy of pancreaticobiliary disorders. The complementary nature of alternative diagnostic tools such as EUS suggests that ERCP use will continue at its current rate, rather than fall out of favor.