REVIEW Korean J Intern Med 2021;36:25-31 https://doi.org/10.3904/kjim.2020.537 Gallstone pancreatitis: general clinical approach and the role of endoscopic retrograde cholangiopancreatography Shanker Kundumadam, Evan L. Fogel, and Mark Andrew Gromski Division of Gastroenterology and Gallstones account for majority of acute pancreatitis in the Western world. In- Hepatology, Indiana University crease in number and smaller size of the stones increases the risk for biliary School of Medicine, Indianapolis, IN, USA pancreatitis. In addition to features of acute pancreatitis, these patients also have cholestatic clinical picture. Fluid therapy and enteral nutrition are vital compo- nents in management of any case of acute pancreatitis. During initial evaluation, Received : October 2, 2020 a right upper quadrant ultrasonogram is particularly important. On a case-by- Accepted : November 2, 2020 case basis, further advanced imaging studies such as magnetic resonance chol- angiopancreatography or endoscopic ultrasound may be warranted. Acute man- Correspondence to Mark Andrew Gromski, M.D. agement also involves monitoring for local and systemic complications. Patients Division of Gastroenterology are triaged based on predictors of ongoing biliary obstruction in order to identify and Hepatology, Indiana who would need endoscopic retrograde cholangiopancreatography. Index cho- University School of Medicine, 550 N. University Blvd, Suite 1634, lecystectomy is safe and recommended, with exception of cases with significant Indianapolis, IN 46202, USA local and systemic complications where delayed cholecystectomy may be safer. Tel: +1-317-944-0925 Fax: +1-317-968-1265 Keywords: Pancreatitis; Cholangiopancreatography, endoscopic retrograde; Cho- E-mail: [email protected] https://orcid.org/0000-0002- lecystectomy 9035-2434 INTRODUCTION a primary bile duct stone or secondary gallbladder stone may pass through the ampulla of Vater. Ampullary ob- Acute pancreatitis is a condition characterized by acute struction, local inflammation due to stone passage at inflammation of the pancreas [1]. There are multiple the level of the ampulla of Vater and transient bile reflux risk factors and putative etiologies of acute pancreatitis; into the pancreatic duct are all potential mechanisms to however, gallstones and alcohol are the identified eti- explain gallstone pancreatitis [6]. The risk of gallstone ology in up to 70% of cases [2,3]. In the Western world, pancreatitis increases with smaller gallstones (allowing gallstones are the leading cause of acute pancreatitis, more unrestricted passage into the common bile duct causing up to 40% of cases [4]. For patients who harbor and across the ampulla), and increased number of gall- gallstones, the risk of biliary pancreatitis is up to 7% on stones [7]. long term follow-up [5]. Multiple hypotheses exist to ex- Acute pancreatitis of any etiology is diagnosed if two plain the mechanism by which stones cause pancreatitis. of the following three criteria are filled: (1) upper abdom- Invariably, the stone must exit the gallbladder through inal or back pain consistent with pancreas type pain, (2) the cystic duct and cause acute pancreatitis from being increased pancreatic enzyme levels (lipase or amylase) > lodged at the pancreatobiliary junction or alternatively, 3 times the upper limit of normal, and (3) pancreatic in- Copyright © 2021 The Korean Association of Internal Medicine pISSN 1226-3303 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ eISSN 2005-6648 by-nc/4.0/) which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited4 http://www.kjim.org The Korean Journal of Internal Medicine Vol. 36, No. 1, January 2021 Acute pancreatitis GENERAL APPROACH TO MANAGEMENT Mild Moderate Severe Fluid therapy and nutrition Patients suspected to have acute pancreatitis or diag- No local/systemic Local/systemic Local/systemic nosed with acute pancreatitis should be appropriately complications complications complications triaged and resuscitated. The American College of Gas- Transient organ Persistent organ troenterology guidelines for the management of acute No organ failure failure (< 48 hours) failure (> 48 hours) pancreatitis published in 2013 recommend admission to the intensive care unit for patients who present with Figure 1. Revised Atlanta classification on severity of pan- organ failure or fulfilling SIRS criteria [8]. Fluid therapy creatitis. remains of utmost importance in management of acute pancreatitis. Judicious goal-directed intravenous (IV) fluid therapy with normal saline or Ringer’s lactate has flammation on abdominal imaging (usually computed been recommended by the American Gastroenterologi- tomography [CT] or magnetic resonance imaging) [8,9]. cal Association (AGA) in its guideline published in 2018. The abdominal pain is usually epigastric in location and The titration of fluids to clinical and biochemical tar- radiates to the thoracic back, but may also be solely lo- gets of perfusion such as blood urea nitrogen, hemato- cated in the back or in the left or right upper quadrants. crit, heart rate and mean arterial pressure is appropriate Nausea and emesis are also often predominant symp- [13]. After an initial bolus of IV fluids, we often start IV toms [10]. The revised Atlanta classification is widely hydration with Ringer’s lactate at a rate of 3 cc/kg/hr for used to stratify the severity of acute pancreatitis, based the first 24 hours in adults, with some variability based on the presence or absence of local/systemic complica- on ideal body weight, co-morbidities (for instance re- tions and the presence or absence of concomitant organ nal, cardiac or pulmonary disease) and clinical scenario. failure (Fig. 1) [9]. Due to this wide range in presenta- Overhydration should be avoided as this may increase tion, physical examination findings can vary significant- the risk of acute respiratory distress syndrome (ARDS) ly from patient to patient. In addition to the classically [14,15]. It is also important to initiate early oral feeding described clinical findings of abdominal tenderness, within 24 hours. Enteral feeding with a nasogastric or other clinical signs of ileus (distended, tympanic abdo- nasojejunal tube is appropriate in patients unable to tol- men) and features of systemic inflammatory response erate oral feeding. Prophylactic antibiotics are not rec- syndrome (SIRS) may be encountered. Characteristics ommended in routine cases of acute pancreatitis where of biliary obstruction including dark urine, pale stools, infection is not suspected [13]. icteric sclerae, excoriations from pruritis and jaundice may be valuable clues pointing towards gallstones as the Imaging studies etiological culprit for an episode of acute pancreatitis. An ultrasound (US) of the abdomen is the most appro- The presence of risk factors for gallstones, such as older priate imaging study in the initial evaluation of sus- age, female gender, obesity, rapid weight loss, pregnancy pected gallstone pancreatitis. It has a sensitivity and or hormone therapy with estrogen may also increase the specificity of 84% and 99%, respectively, in identifying level of suspicion for biliary pancreatitis [11]. Elevated gallbladder stones [16]. This also facilitates visualization liver tests at the time of presentation for acute pancre- of the biliary tract to identify bile duct stones or bili- atitis also raises this suspicion. Specifically, an elevated ary dilatation, which increases the suspicion for biliary alanine transaminase level more than three times upper obstruction. The integration of clinical findings (pres- limit of normal (with a greater level than the aspartate ence or absence of jaundice), US findings (presence or aminotransferase) is a relatively specific indication of a absence of gallstones in gallbladder, stones in common biliary etiology under appropriate circumstances [12]. bile duct or biliary dilation), along with laboratory test results (transaminases, alkaline phosphatase, and bili- 26 www.kjim.org https://doi.org/10.3904/kjim.2020.537 Kundumadam S, et al. Gallstone pancreatitis rubin levels) facilitate decision-making on predicting the upper limit of normal), a CT scan is not necessary on the probability of persistent biliary obstruction and the initial evaluation. A CT scan may, at times, identify an need for endoscopic intervention in cases of suspected impacted stone at the level of the ampulla of Vater (Fig. gallstone pancreatitis. If a patient meets the diagnosis 2); however, this is not the most sensitive radiographic for acute pancreatitis without cross-sectional imaging test for detection of biliary stones. If there continues to (having abdominal pain and pancreas enzymes > 3 times be a clinical question after initial work-up for the eti- ology of acute pancreatitis, magnetic resonance cholan- giopancreatography (MRCP) or endoscopic ultrasound (EUS) (Fig. 3) have better performance characteristics for detecting common bile duct stones than CT scan [17]. Monitoring for complications During the management of acute pancreatitis, potential local and systemic complications should be anticipated. Local complications include acute peripancreatic fluid collections, acute necrotic collections indicative of pan- creas necrosis, mesenteric vein thrombosis, and infec- tion. Deteriorating clinical status, persistent abdominal pain,