Bilirubin-based decision-making for MRCP use in acute biliary pancreatitis: a retrospective cohort study

Bilirubin-based decision-making for MRCP use in acute biliary pancreatitis: a retrospective cohort study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Bilirubin-based decision-making for MRCP use in acute biliary pancreatitis: a retrospective cohort study Merve Karli, Alpen Yahya Gumusoglu, Hamid Ahmet Kabuli, Mehmet Karabulut, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8581696/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 14 You are reading this latest preprint version Abstract Background Differentiating cholangitis and determining the necessity of biliary drainage in acute biliary pancreatitis accompanied by hyperbilirubinemia remains clinically challenging. Although magnetic resonance cholangiopancreatography (MRCP) is frequently used, standardized bilirubin thresholds guiding its use have not been clearly defined. Methods This retrospective observational cohort study included 158 patients diagnosed with acute biliary pancreatitis and hyperbilirubinemia who underwent MRCP between January 2017 and December 2019. Patients were categorized according to MRCP findings and endoscopic retrograde cholangiopancreatography (ERCP) requirement. Demographic characteristics, pancreatitis severity, laboratory parameters, clinical outcomes, and complications were analyzed. Receiver operating characteristic (ROC) curve analysis and Youden’s J index were used to determine optimal bilirubin cut-off values. Results MRCP demonstrated high diagnostic accuracy, with a sensitivity of 95.45% and specificity of 98.13%. The optimal bilirubin thresholds indicating the need for MRCP were identified as total bilirubin ≥ 3.78 mg/dL and direct bilirubin ≥ 2.80 mg/dL. Conclusion A bilirubin-based clinical decision-making algorithm may optimize MRCP utilization and reduce unnecessary ERCP procedures in patients with acute biliary pancreatitis. Acute biliary pancreatitis Magnetic resonance cholangiopancreatography Hyperbilirubinemia Choledocholithiasis Endoscopic retrograde cholangiopancreatography Clinical decision-making algorithm Figures Figure 1 INTRODUCTION Acute biliary pancreatitis is a common cause of hospital admission and is associated with significant morbidity and mortality (1). Determining the presence of cholangitis and the need for biliary drainage in the setting of mechanical jaundice remains a major clinical challenge. Current guidelines recommend ERCP in patients with cholangitis or persistent biliary obstruction; however, objective criteria guiding MRCP use are lacking (2,3). MRCP accurately evaluates the biliary tree and detects choledocholithiasis while avoiding the risks of invasive procedures such as ERCP (4–6). Nevertheless, the absence of standardized bilirubin thresholds may result in unnecessary imaging or interventions. This study aimed to define bilirubin-based thresholds for MRCP utilization and propose a structured clinical decision-making algorithm for patients with acute biliary pancreatitis and hyperbilirubinemia. MATERIALS AND METHODS Study design and ethical approval This retrospective observational cohort study was conducted in accordance with the principles of the Declaration of Helsinki and Good Clinical Practice guidelines. Ethical approval was obtained from the Ethics Committee of Bakırköy Dr. Sadi Konuk Training and Research Hospital, University of Health Sciences, in February 2020 (protocol number: 2020/41). Patient selection A total of 158 patients diagnosed with acute biliary pancreatitis and hyperbilirubinemia who underwent MRCP between January 2017 and December 2019 were included. Patients with a history of biliopancreatic surgery or contraindications to MRCP were excluded. Clinical assessment The diagnosis and severity of acute pancreatitis were determined according to the 2012 Revised Atlanta Classification. Demographic data, laboratory findings, imaging results, treatment modalities, and clinical outcomes were retrospectively analyzed. Imaging and interventions Patients were divided into two groups based on MRCP findings and subsequent endoscopic evaluation. Group 1 consisted of patients in whom no pathology was detected on MRCP and who did not undergo ERCP, whereas Group 2 consisted of patients in whom biliary pathology was detected on MRCP and subsequently confirmed by ERCP. Statistical analysis ROC curve analysis and Youden’s J index were used to identify optimal bilirubin cut-off values. A p value < 0.05 was considered statistically significant. RESULTS A total of 158 patients diagnosed with acute biliary pancreatitis accompanied by hyperbilirubinemia were included in the study. Among these patients, 105 patients in whom no pathology was detected on MRCP and who did not undergo ERCP were classified as Group 1, whereas 42 patients in whom pathology was detected on MRCP and subsequently confirmed by ERCP were classified as Group 2. The demographic, laboratory, and baseline clinical characteristics of the patients enrolled in the study are summarized in Table 1. Overall, 85 patients (53.8%) were female, and the mean age of the study population was 55.17 ± 18.16 years. Baseline laboratory values and clinical characteristics were comparable between Group 1 and Group 2. The diagnostic efficacy of MRCP in detecting biliary pathology is presented in Table 2. When ERCP findings were used as the reference standard, MRCP demonstrated high diagnostic performance, with a sensitivity of 95.45% and a specificity of 98.13%. Receiver operating characteristic (ROC) curve analysis was performed to determine optimal bilirubin thresholds for predicting biliary pathology on MRCP. The identified bilirubin cut-off values are presented in Table 3. The optimal thresholds were determined as ≥3.78 mg/dL for total bilirubin and ≥2.80 mg/dL for direct bilirubin. The severity of acute pancreatitis according to the 2012 Revised Atlanta Classification, stratified by study groups, is shown in Table 4. The majority of patients in both groups had mild pancreatitis, and no statistically significant difference in pancreatitis severity was observed between Group 1 and Group 2. A comparison of age, body mass index (BMI), Charlson comorbidity index, and length of hospital stay between the two groups is presented in Table 5. No significant differences were identified between Group 1 and Group 2 with respect to these parameters. Based on MRCP findings and the identified bilirubin cut-off values, a bilirubin-based clinical decision-making algorithm for MRCP utilization in patients with acute biliary pancreatitis was developed (Figure 1). DISCUSSION Magnetic resonance cholangiopancreatography (MRCP) is widely accepted as a reliable, non-invasive imaging modality for evaluating the biliary tree in patients with acute biliary pancreatitis. Current international guidelines emphasize the importance of identifying patients who require biliary intervention while avoiding unnecessary invasive procedures such as diagnostic ERCP (1). In this context, MRCP has been shown to accurately detect choledocholithiasis with high sensitivity and specificity, making it a valuable tool in clinical decision-making (2,3). The demographic characteristics of our study population are consistent with previously published epidemiological data on acute biliary pancreatitis. Large population-based and regional studies have reported a predominance of middle-aged patients and a higher incidence among women, reflecting the epidemiology of gallstone disease (4–6). In line with these findings, no significant demographic differences were observed between patients with and without choledocholithiasis in our cohort. Despite broad consensus regarding the role of ERCP in patients with cholangitis or persistent biliary obstruction, the criteria guiding further imaging remain heterogeneous. Landmark randomized trials and guideline documents support early ERCP in selected high-risk patients but do not define objective biochemical thresholds for MRCP utilization (7–10). This lack of standardization may contribute to variability in practice and unnecessary invasive procedures. Our study addresses this gap by identifying specific total and direct bilirubin thresholds associated with bile duct pathology on MRCP. The proposed cut-off values provide objective, clinically applicable criteria that may assist clinicians in selecting patients who are most likely to benefit from MRCP. Similar approaches combining laboratory parameters with imaging findings have been shown to improve diagnostic efficiency and optimize resource utilization (11,12). In patients with negative MRCP findings, the role of endoscopic ultrasound (EUS) remains a subject of debate. Although EUS may detect small bile duct stones missed by MRCP, routine use of EUS in all MRCP-negative patients is not universally recommended (13). In our cohort, the absence of confirmatory ERCP in MRCP-negative patients reflects real-world, guideline-based practice and avoids unnecessary invasive interventions. Beyond stone detection, MRCP may reveal rare but clinically significant conditions such as periampullary tumors or biliary hydatid disease, which can present with obstructive jaundice and acute pancreatitis and require distinct management strategies (14,15). This highlights the broader diagnostic value of MRCP in patients with hyperbilirubinemia. Finally, structured clinical algorithms integrating laboratory thresholds and imaging findings have been shown to improve outcomes and reduce unnecessary interventions in hepatobiliary disease (16,17). The bilirubin-based clinical decision-making algorithm proposed in this study represents a practical tool that reflects real-world practice and may enhance patient selection for MRCP and subsequent biliary interventions. CONCLUSION MRCP should be considered in patients with acute biliary pancreatitis when total bilirubin is ≥3.78 mg/dL and direct bilirubin is ≥2.80 mg/dL. Adoption of this bilirubin-based algorithm may enhance clinical decision-making and optimize biliary intervention strategies. Declarations Consent to Participate Written informed consent was obtained from all participants or their legal representatives. Due to the retrospective nature of the study, the requirement for additional informed consent was waived by the local ethics committee. Funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Reporting guidelines This study was conducted and reported in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines for observational studies. Consent for publication Not Applicable. Availability of Data and Materials The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request. References Tenner S, Baillie J, DeWitt J, Vege SS. American College of Gastroenterology guideline: management of acute pancreatitis. Am J Gastroenterol. 2013;108(9):1400–1416. Moon JH, Cho YD, Cha SW, et al. The role of magnetic resonance cholangiopancreatography in patients with suspected biliary pancreatitis. Am J Gastroenterol. 2005;100(5):1051–1057. Hallal AH, Amortegui JD, Jeroukhimov I, et al. Magnetic resonance cholangiopancreatography accurately detects common bile duct stones in patients with gallstone pancreatitis. J Am Coll Surg. 2005;200(6):869–875. Xiao AY, Tan ML, Wu LM, et al. Global incidence and mortality of pancreatic diseases: a systematic review, meta-analysis, and meta-regression of population-based cohort studies. Lancet Gastroenterol Hepatol. 2016;1(1):45–55. Yıldız H, Yıldız F, Yılmaz H, et al. Evaluation of patients with acute biliary pancreatitis: a single-center retrospective study. Turk J Gastroenterol. 2021;32(2):144–150. Shrestha S, Shrestha R, Shrestha A, et al. Clinical profile of acute biliary pancreatitis in a tertiary care center. JNMA J Nepal Med Assoc. 2019;57(216):219–224. Neoptolemos JP, Carr-Locke DL, London NJ, et al. Controlled trial of urgent endoscopic retrograde cholangiopancreatography and endoscopic sphincterotomy versus conservative treatment for acute pancreatitis due to gallstones. Lancet. 1988;2(8618):979–983. Fölsch UR, Nitsche R, Lüdtke R, et al. Early ERCP and papillotomy compared with conservative treatment for acute biliary pancreatitis. N Engl J Med. 1997;336(4):237–242. Yokoe M, Takada T, Mayumi T, et al. Japanese guidelines for the management of acute pancreatitis: JPN guidelines 2015. J Hepatobiliary Pancreat Sci. 2015;22(6):405–432. Olson E, Perelman S, Birk JW. When to perform ERCP in acute biliary pancreatitis. Postgrad Med J. 2019;95(1124):328–333. Makary MA, Duncan MD, Harmon JW, et al. The role of magnetic resonance cholangiopancreatography in the management of patients with gallstone pancreatitis. Ann Surg. 2005;241(1):119–124. Mofidi R, Duff MD, Wigmore SJ, et al. Association between early systemic inflammatory response, severity of multiorgan dysfunction and death in acute pancreatitis. Pancreatology. 2008;8(1):55–60. Tse F, Yuan Y. Early routine endoscopic ultrasound in acute biliary pancreatitis: a systematic review and meta-analysis. Cochrane Database Syst Rev. 2012;(5):CD009779. Chen WX, Li YM, Yu CH, et al. Periampullary carcinoma presenting as acute pancreatitis: clinical features and imaging findings. Hepatobiliary Pancreat Dis Int. 2008;7(6):649–653. Katsinelos P, Chatzimavroudis G, Zavos C, et al. Biliary hydatid disease presenting as obstructive jaundice and acute pancreatitis: a case report. Cases J. 2009;2:7374. Arguedas MR, Heudebert GR, Stinnett AA, et al. Biliary tract disease in the elderly: algorithmic approach and cost-effectiveness of diagnostic strategies. Am J Gastroenterol. 2001;96(10):2892–2899. Prasanth J, Kumar V, Reddy PK, et al. Implementation of a clinical algorithm improves outcomes in acute pancreatitis: a prospective study. World J Surg. 2022;46(6):1359–1375. Tables Tables 1 to 5 are available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files 4Table1.docx 5Table2.docx 6Table3.docx 7Table4.docx 8Table5.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 27 Apr, 2026 Reviews received at journal 18 Apr, 2026 Reviewers agreed at journal 09 Apr, 2026 Reviewers agreed at journal 28 Mar, 2026 Reviewers agreed at journal 22 Mar, 2026 Reviews received at journal 17 Feb, 2026 Reviews received at journal 14 Feb, 2026 Reviewers agreed at journal 12 Feb, 2026 Reviewers agreed at journal 11 Feb, 2026 Reviewers invited by journal 11 Feb, 2026 Editor assigned by journal 09 Feb, 2026 Editor invited by journal 19 Jan, 2026 Submission checks completed at journal 17 Jan, 2026 First submitted to journal 17 Jan, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8581696","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":591531011,"identity":"69ca3d13-b832-4693-9479-ada60e453b18","order_by":0,"name":"Merve Karli","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4ElEQVRIie3PsQrCMBCA4YSD6xLs2lJ9BKFSKLjUhyl0EhycxMFB0EV3nyRzoZAufYBAB62Ccx0EBQdTN5caN8H8w3HDfZAQYjL9bCkhHUB6UCvraBMEBL8hqE8IotPsH0l/vT07dRFN0MJkdh1HXSRQHWULCYs8dHcyHq4ARdnjsXoYBsG4jcgEAlaDj2CtSpeDIgy9VrI/Q/CoFy8ydflCg0ikJyIzRVDQC880SJHQalPkDYk9ynOmlg9/yQVJb2Lu27YYXO58PrKtZXVqI28Be03d8yZ6++baZDKZ/qYnrQ9AR390x/IAAAAASUVORK5CYII=","orcid":"","institution":"Hisar Hospital Intercontinental","correspondingAuthor":true,"prefix":"","firstName":"Merve","middleName":"","lastName":"Karli","suffix":""},{"id":591531017,"identity":"95ad1fc0-4f0b-483e-ac90-fb4595220020","order_by":1,"name":"Alpen Yahya Gumusoglu","email":"","orcid":"","institution":"Bakırköy Dr.Sadi Konuk Eğitim ve Araştırma Hastanesi","correspondingAuthor":false,"prefix":"","firstName":"Alpen","middleName":"Yahya","lastName":"Gumusoglu","suffix":""},{"id":591531026,"identity":"4fcb2430-9c36-48b7-b112-11f8240a3719","order_by":2,"name":"Hamid Ahmet Kabuli","email":"","orcid":"","institution":"Bakırköy Dr.Sadi Konuk Eğitim ve Araştırma Hastanesi","correspondingAuthor":false,"prefix":"","firstName":"Hamid","middleName":"Ahmet","lastName":"Kabuli","suffix":""},{"id":591531034,"identity":"8e72bad6-0851-4474-9de1-73796425903f","order_by":3,"name":"Mehmet Karabulut","email":"","orcid":"","institution":"Medicana Hospital","correspondingAuthor":false,"prefix":"","firstName":"Mehmet","middleName":"","lastName":"Karabulut","suffix":""},{"id":591531040,"identity":"7ce667be-fe5a-4657-a0d5-c41ac5ff482e","order_by":4,"name":"Kivanc Derya Peker","email":"","orcid":"","institution":"Hisar Hospital Intercontinental","correspondingAuthor":false,"prefix":"","firstName":"Kivanc","middleName":"Derya","lastName":"Peker","suffix":""},{"id":591531046,"identity":"153ef153-840c-4f80-922b-d5dea890dadd","order_by":5,"name":"Ali Kocatas","email":"","orcid":"","institution":"İstanbul Kanuni Sultan Süleyman Eğitim ve Araştırma Hastanesi","correspondingAuthor":false,"prefix":"","firstName":"Ali","middleName":"","lastName":"Kocatas","suffix":""}],"badges":[],"createdAt":"2026-01-12 12:24:02","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8581696/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8581696/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":102807155,"identity":"0d703b97-c54e-429d-8d46-6ae22e127193","added_by":"auto","created_at":"2026-02-17 00:53:58","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":35457,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eBilirubin-based clinical decision-making algorithm for MRCP use in acute biliary pancreatitis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis flow chart illustrates a bilirubin-based clinical decision-making algorithm for patients with acute biliary pancreatitis. Magnetic resonance cholangiopancreatography (MRCP) is performed in patients with total bilirubin levels ≥3.7 mg/dL during hospitalization or follow-up, and subsequent management is guided by MRCP findings and the clinical course of obstructive jaundice.\u003c/p\u003e\n\u003cp\u003ePatients with pathology detected on MRCP and regression of obstructive jaundice undergo early cholecystectomy with intraoperative cholangiography, whereas patients with pathology detected on MRCP and persistent obstructive jaundice are managed with endoscopic retrograde cholangiopancreatography (ERCP). In patients with no pathology detected on MRCP, endoscopic ultrasound (EUS) is performed when obstructive jaundice persists, while early cholecystectomy during the index hospitalization is recommended for patients with regression of obstructive jaundice and mild pancreatitis.\u003c/p\u003e\n\u003cp\u003eThis algorithm is consistent with current international guidelines and provides a structured approach to optimize biliary imaging and intervention while minimizing unnecessary invasive procedures.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8581696/v1/01b11c2991c5621c987bce90.png"},{"id":102807164,"identity":"d2c0a47e-7523-4fa0-ae48-3ce87e164130","added_by":"auto","created_at":"2026-02-17 00:54:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":390985,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8581696/v1/b7540eca-6fa7-4e31-a721-80dc2db78d90.pdf"},{"id":102807147,"identity":"c3ba35ef-3549-46b4-b967-079d60f62ec5","added_by":"auto","created_at":"2026-02-17 00:53:54","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":16742,"visible":true,"origin":"","legend":"","description":"","filename":"4Table1.docx","url":"https://assets-eu.researchsquare.com/files/rs-8581696/v1/a8bdabffa41c390decee649e.docx"},{"id":102807158,"identity":"09c1db50-c5b3-4e09-82c3-8c5e4db4cae5","added_by":"auto","created_at":"2026-02-17 00:53:59","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":17184,"visible":true,"origin":"","legend":"","description":"","filename":"5Table2.docx","url":"https://assets-eu.researchsquare.com/files/rs-8581696/v1/6bf18ca0d6d76bad12380441.docx"},{"id":102807156,"identity":"9c17900e-78c6-4b5b-82f6-a4cb7346aa1a","added_by":"auto","created_at":"2026-02-17 00:53:58","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":15455,"visible":true,"origin":"","legend":"","description":"","filename":"6Table3.docx","url":"https://assets-eu.researchsquare.com/files/rs-8581696/v1/68041ba51a2fa022d2503182.docx"},{"id":102807149,"identity":"baf6d3a8-ee27-4b32-8450-dbb31f16df9a","added_by":"auto","created_at":"2026-02-17 00:53:54","extension":"docx","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":15022,"visible":true,"origin":"","legend":"","description":"","filename":"7Table4.docx","url":"https://assets-eu.researchsquare.com/files/rs-8581696/v1/9be2b8a1777d31db4dc93275.docx"},{"id":102807161,"identity":"4947fbad-a407-4c2a-924c-afcafa153f61","added_by":"auto","created_at":"2026-02-17 00:53:59","extension":"docx","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":15238,"visible":true,"origin":"","legend":"","description":"","filename":"8Table5.docx","url":"https://assets-eu.researchsquare.com/files/rs-8581696/v1/3fee4b39d9bbe033cd2ead21.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Bilirubin-based decision-making for MRCP use in acute biliary pancreatitis: a retrospective cohort study","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eAcute biliary pancreatitis is a common cause of hospital admission and is associated with significant morbidity and mortality (1). Determining the presence of cholangitis and the need for biliary drainage in the setting of mechanical jaundice remains a major clinical challenge. Current guidelines recommend ERCP in patients with cholangitis or persistent biliary obstruction; however, objective criteria guiding MRCP use are lacking (2,3).\u003c/p\u003e \u003cp\u003eMRCP accurately evaluates the biliary tree and detects choledocholithiasis while avoiding the risks of invasive procedures such as ERCP (4\u0026ndash;6). Nevertheless, the absence of standardized bilirubin thresholds may result in unnecessary imaging or interventions. This study aimed to define bilirubin-based thresholds for MRCP utilization and propose a structured clinical decision-making algorithm for patients with acute biliary pancreatitis and hyperbilirubinemia.\u003c/p\u003e"},{"header":"MATERIALS AND METHODS","content":"\u003cp\u003eStudy design and ethical approval\u003c/p\u003e \u003cp\u003e This retrospective observational cohort study was conducted in accordance with the principles of the Declaration of Helsinki and Good Clinical Practice guidelines. Ethical approval was obtained from the Ethics Committee of Bakırk\u0026ouml;y Dr. Sadi Konuk Training and Research Hospital, University of Health Sciences, in February 2020 (protocol number: 2020/41).\u003c/p\u003e \u003cp\u003ePatient selection\u003c/p\u003e \u003cp\u003eA total of 158 patients diagnosed with acute biliary pancreatitis and hyperbilirubinemia who underwent MRCP between January 2017 and December 2019 were included. Patients with a history of biliopancreatic surgery or contraindications to MRCP were excluded.\u003c/p\u003e \u003cp\u003eClinical assessment\u003c/p\u003e \u003cp\u003eThe diagnosis and severity of acute pancreatitis were determined according to the 2012 Revised Atlanta Classification. Demographic data, laboratory findings, imaging results, treatment modalities, and clinical outcomes were retrospectively analyzed.\u003c/p\u003e \u003cp\u003eImaging and interventions\u003c/p\u003e \u003cp\u003ePatients were divided into two groups based on MRCP findings and subsequent endoscopic evaluation. Group 1 consisted of patients in whom no pathology was detected on MRCP and who did not undergo ERCP, whereas Group 2 consisted of patients in whom biliary pathology was detected on MRCP and subsequently confirmed by ERCP.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eROC curve analysis and Youden\u0026rsquo;s J index were used to identify optimal bilirubin cut-off values. A p value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003eA total of 158 patients diagnosed with acute biliary pancreatitis accompanied by hyperbilirubinemia were included in the study. Among these patients, 105 patients in whom no pathology was detected on MRCP and who did not undergo ERCP were classified as Group 1, whereas 42 patients in whom pathology was detected on MRCP and subsequently confirmed by ERCP were classified as Group 2.\u003c/p\u003e\n\u003cp\u003eThe demographic, laboratory, and baseline clinical characteristics of the patients enrolled in the study are summarized in Table 1. Overall, 85 patients (53.8%) were female, and the mean age of the study population was 55.17 \u0026plusmn; 18.16 years. Baseline laboratory values and clinical characteristics were comparable between Group 1 and Group 2.\u003c/p\u003e\n\u003cp\u003eThe diagnostic efficacy of MRCP in detecting biliary pathology is presented in Table 2. When ERCP findings were used as the reference standard, MRCP demonstrated high diagnostic performance, with a sensitivity of 95.45% and a specificity of 98.13%.\u003c/p\u003e\n\u003cp\u003eReceiver operating characteristic (ROC) curve analysis was performed to determine optimal bilirubin thresholds for predicting biliary pathology on MRCP. The identified bilirubin cut-off values are presented in Table 3. The optimal thresholds were determined as \u0026ge;3.78 mg/dL for total bilirubin and \u0026ge;2.80 mg/dL for direct bilirubin.\u003c/p\u003e\n\u003cp\u003eThe severity of acute pancreatitis according to the 2012 Revised Atlanta Classification, stratified by study groups, is shown in Table 4. The majority of patients in both groups had mild pancreatitis, and no statistically significant difference in pancreatitis severity was observed between Group 1 and Group 2.\u003c/p\u003e\n\u003cp\u003eA comparison of age, body mass index (BMI), Charlson comorbidity index, and length of hospital stay between the two groups is presented in Table 5. No significant differences were identified between Group 1 and Group 2 with respect to these parameters.\u003c/p\u003e\n\u003cp\u003eBased on MRCP findings and the identified bilirubin cut-off values, a bilirubin-based clinical decision-making algorithm for MRCP utilization in patients with acute biliary pancreatitis was developed (Figure 1).\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eMagnetic resonance cholangiopancreatography (MRCP) is widely accepted as a reliable, non-invasive imaging modality for evaluating the biliary tree in patients with acute biliary pancreatitis. Current international guidelines emphasize the importance of identifying patients who require biliary intervention while avoiding unnecessary invasive procedures such as diagnostic ERCP (1). In this context, MRCP has been shown to accurately detect choledocholithiasis with high sensitivity and specificity, making it a valuable tool in clinical decision-making (2,3).\u003c/p\u003e\n\u003cp\u003eThe demographic characteristics of our study population are consistent with previously published epidemiological data on acute biliary pancreatitis. Large population-based and regional studies have reported a predominance of middle-aged patients and a higher incidence among women, reflecting the epidemiology of gallstone disease (4\u0026ndash;6). In line with these findings, no significant demographic differences were observed between patients with and without choledocholithiasis in our cohort.\u003c/p\u003e\n\u003cp\u003eDespite broad consensus regarding the role of ERCP in patients with cholangitis or persistent biliary obstruction, the criteria guiding further imaging remain heterogeneous. Landmark randomized trials and guideline documents support early ERCP in selected high-risk patients but do not define objective biochemical thresholds for MRCP utilization (7\u0026ndash;10). This lack of standardization may contribute to variability in practice and unnecessary invasive procedures.\u003c/p\u003e\n\u003cp\u003eOur study addresses this gap by identifying specific total and direct bilirubin thresholds associated with bile duct pathology on MRCP. The proposed cut-off values provide objective, clinically applicable criteria that may assist clinicians in selecting patients who are most likely to benefit from MRCP. Similar approaches combining laboratory parameters with imaging findings have been shown to improve diagnostic efficiency and optimize resource utilization (11,12).\u003c/p\u003e\n\u003cp\u003eIn patients with negative MRCP findings, the role of endoscopic ultrasound (EUS) remains a subject of debate. Although EUS may detect small bile duct stones missed by MRCP, routine use of EUS in all MRCP-negative patients is not universally recommended (13). In our cohort, the absence of confirmatory ERCP in MRCP-negative patients reflects real-world, guideline-based practice and avoids unnecessary invasive interventions.\u003c/p\u003e\n\u003cp\u003eBeyond stone detection, MRCP may reveal rare but clinically significant conditions such as periampullary tumors or biliary hydatid disease, which can present with obstructive jaundice and acute pancreatitis and require distinct management strategies (14,15). This highlights the broader diagnostic value of MRCP in patients with hyperbilirubinemia.\u003c/p\u003e\n\u003cp\u003eFinally, structured clinical algorithms integrating laboratory thresholds and imaging findings have been shown to improve outcomes and reduce unnecessary interventions in hepatobiliary disease (16,17). The bilirubin-based clinical decision-making algorithm proposed in this study represents a practical tool that reflects real-world practice and may enhance patient selection for MRCP and subsequent biliary interventions.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eMRCP should be considered in patients with acute biliary pancreatitis when total bilirubin is \u0026ge;3.78 mg/dL and direct bilirubin is \u0026ge;2.80 mg/dL. Adoption of this bilirubin-based algorithm may enhance clinical decision-making and optimize biliary intervention strategies.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eConsent to Participate\u003c/p\u003e\n\u003cp\u003eWritten informed consent was obtained from all participants or their legal representatives. Due to the retrospective nature of the study, the requirement for additional informed consent was waived by the local ethics committee.\u003c/p\u003e\n\u003cp\u003eFunding\u003c/p\u003e\n\u003cp\u003eThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003eReporting guidelines\u003c/p\u003e\n\u003cp\u003eThis study was conducted and reported in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines for observational studies.\u003c/p\u003e\n\u003cp\u003eConsent for publication\u003c/p\u003e\n\u003cp\u003eNot Applicable.\u003c/p\u003e\n\u003cp\u003eAvailability of Data and Materials\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eTenner S, Baillie J, DeWitt J, Vege SS. American College of Gastroenterology guideline: management of acute pancreatitis. Am J Gastroenterol. 2013;108(9):1400\u0026ndash;1416.\u003c/li\u003e\n\u003cli\u003eMoon JH, Cho YD, Cha SW, et al. The role of magnetic resonance cholangiopancreatography in patients with suspected biliary pancreatitis. Am J Gastroenterol. 2005;100(5):1051\u0026ndash;1057.\u003c/li\u003e\n\u003cli\u003eHallal AH, Amortegui JD, Jeroukhimov I, et al. Magnetic resonance cholangiopancreatography accurately detects common bile duct stones in patients with gallstone pancreatitis. J Am Coll Surg. 2005;200(6):869\u0026ndash;875.\u003c/li\u003e\n\u003cli\u003eXiao AY, Tan ML, Wu LM, et al. Global incidence and mortality of pancreatic diseases: a systematic review, meta-analysis, and meta-regression of population-based cohort studies. Lancet Gastroenterol Hepatol. 2016;1(1):45\u0026ndash;55.\u003c/li\u003e\n\u003cli\u003eYıldız H, Yıldız F, Yılmaz H, et al. Evaluation of patients with acute biliary pancreatitis: a single-center retrospective study. Turk J Gastroenterol. 2021;32(2):144\u0026ndash;150.\u003c/li\u003e\n\u003cli\u003eShrestha S, Shrestha R, Shrestha A, et al. Clinical profile of acute biliary pancreatitis in a tertiary care center. JNMA J Nepal Med Assoc. 2019;57(216):219\u0026ndash;224.\u003c/li\u003e\n\u003cli\u003eNeoptolemos JP, Carr-Locke DL, London NJ, et al. Controlled trial of urgent endoscopic retrograde cholangiopancreatography and endoscopic sphincterotomy versus conservative treatment for acute pancreatitis due to gallstones. Lancet. 1988;2(8618):979\u0026ndash;983.\u003c/li\u003e\n\u003cli\u003eF\u0026ouml;lsch UR, Nitsche R, L\u0026uuml;dtke R, et al. Early ERCP and papillotomy compared with conservative treatment for acute biliary pancreatitis. N Engl J Med. 1997;336(4):237\u0026ndash;242.\u003c/li\u003e\n\u003cli\u003eYokoe M, Takada T, Mayumi T, et al. Japanese guidelines for the management of acute pancreatitis: JPN guidelines 2015. J Hepatobiliary Pancreat Sci. 2015;22(6):405\u0026ndash;432.\u003c/li\u003e\n\u003cli\u003eOlson E, Perelman S, Birk JW. When to perform ERCP in acute biliary pancreatitis. Postgrad Med J. 2019;95(1124):328\u0026ndash;333.\u003c/li\u003e\n\u003cli\u003eMakary MA, Duncan MD, Harmon JW, et al. The role of magnetic resonance cholangiopancreatography in the management of patients with gallstone pancreatitis. Ann Surg. 2005;241(1):119\u0026ndash;124.\u003c/li\u003e\n\u003cli\u003eMofidi R, Duff MD, Wigmore SJ, et al. Association between early systemic inflammatory response, severity of multiorgan dysfunction and death in acute pancreatitis. Pancreatology. 2008;8(1):55\u0026ndash;60.\u003c/li\u003e\n\u003cli\u003eTse F, Yuan Y. Early routine endoscopic ultrasound in acute biliary pancreatitis: a systematic review and meta-analysis. Cochrane Database Syst Rev. 2012;(5):CD009779.\u003c/li\u003e\n\u003cli\u003eChen WX, Li YM, Yu CH, et al. Periampullary carcinoma presenting as acute pancreatitis: clinical features and imaging findings. Hepatobiliary Pancreat Dis Int. 2008;7(6):649\u0026ndash;653.\u003c/li\u003e\n\u003cli\u003eKatsinelos P, Chatzimavroudis G, Zavos C, et al. Biliary hydatid disease presenting as obstructive jaundice and acute pancreatitis: a case report. Cases J. 2009;2:7374.\u003c/li\u003e\n\u003cli\u003eArguedas MR, Heudebert GR, Stinnett AA, et al. Biliary tract disease in the elderly: algorithmic approach and cost-effectiveness of diagnostic strategies. Am J Gastroenterol. 2001;96(10):2892\u0026ndash;2899.\u003c/li\u003e\n\u003cli\u003ePrasanth J, Kumar V, Reddy PK, et al. Implementation of a clinical algorithm improves outcomes in acute pancreatitis: a prospective study. World J Surg. 2022;46(6):1359\u0026ndash;1375.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTables 1 to 5 are available in the Supplementary Files section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-gastroenterology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmge","sideBox":"Learn more about [BMC Gastroenterology](http://bmcgastroenterol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmge/default.aspx","title":"BMC Gastroenterology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Acute biliary pancreatitis, Magnetic resonance cholangiopancreatography, Hyperbilirubinemia, Choledocholithiasis, Endoscopic retrograde cholangiopancreatography, Clinical decision-making algorithm","lastPublishedDoi":"10.21203/rs.3.rs-8581696/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8581696/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eDifferentiating cholangitis and determining the necessity of biliary drainage in acute biliary pancreatitis accompanied by hyperbilirubinemia remains clinically challenging. Although magnetic resonance cholangiopancreatography (MRCP) is frequently used, standardized bilirubin thresholds guiding its use have not been clearly defined.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eThis retrospective observational cohort study included 158 patients diagnosed with acute biliary pancreatitis and hyperbilirubinemia who underwent MRCP between January 2017 and December 2019. Patients were categorized according to MRCP findings and endoscopic retrograde cholangiopancreatography (ERCP) requirement. Demographic characteristics, pancreatitis severity, laboratory parameters, clinical outcomes, and complications were analyzed. Receiver operating characteristic (ROC) curve analysis and Youden\u0026rsquo;s J index were used to determine optimal bilirubin cut-off values.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eMRCP demonstrated high diagnostic accuracy, with a sensitivity of 95.45% and specificity of 98.13%. The optimal bilirubin thresholds indicating the need for MRCP were identified as total bilirubin\u0026thinsp;\u0026ge;\u0026thinsp;3.78 mg/dL and direct bilirubin\u0026thinsp;\u0026ge;\u0026thinsp;2.80 mg/dL.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eA bilirubin-based clinical decision-making algorithm may optimize MRCP utilization and reduce unnecessary ERCP procedures in patients with acute biliary pancreatitis.\u003c/p\u003e","manuscriptTitle":"Bilirubin-based decision-making for MRCP use in acute biliary pancreatitis: a retrospective cohort study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-17 00:53:21","doi":"10.21203/rs.3.rs-8581696/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-27T11:19:45+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-18T10:46:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"50866028454363188504921560375336806400","date":"2026-04-09T11:43:23+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"249486418118834003314378775486679303106","date":"2026-03-28T12:06:19+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"13614025160610904633472623131298456509","date":"2026-03-23T03:39:22+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-17T19:48:42+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-15T04:38:53+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"43917227349847387223592022404482357081","date":"2026-02-12T13:39:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"125864755361816571134610399012723364557","date":"2026-02-11T17:45:48+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-02-11T07:12:11+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-02-10T04:39:46+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-01-19T05:58:40+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-01-17T06:53:37+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Gastroenterology","date":"2026-01-17T06:46:45+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-gastroenterology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmge","sideBox":"Learn more about [BMC Gastroenterology](http://bmcgastroenterol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmge/default.aspx","title":"BMC Gastroenterology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"6867635f-a5d7-4bf2-9fc9-c14c4be92673","owner":[],"postedDate":"February 17th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-13T04:53:17+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-17 00:53:21","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8581696","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8581696","identity":"rs-8581696","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}