CLINICAL GUIDELINES405CMEACG Clinical Guideline:Diagnosis and Management ofBiliary StricturesB.Joseph Elmunzer,MD,MSc',Jennifer L.Maranki,MD,MSc2,Victoria Gomez,MD,Anna Tavakkoli,MD,MSc45,Bryan G.Sauer,MD,MSc,FACG,Berkeley N.Limketkai,MD,PhD,FACG7,Emily A.Brennan,MLIS,Elaine M.Attridge,MLS9,Tara J.Brigham,MLIS,AHIP10 and Andrew Y.Wang.MDA biliary stricture is an abnormal narrowing in the ductal drainage system of the liver thatcan result in clinically andphysiologically relevant obstruction to the flow of bile.The most common and ominous etiology is malignancy,underscoringthe importance of a high index of suspicion in the evaluation of this condition.The goals of care in patients with a biliarystricture are confirmingorexcluding malignancy(diagnosis)and reestablishing flow of bile to the duodenum(drainage);theapproach to diagnosis and drainage varies according to anatomic location (extrahepatic vs perihilar).For extrahepaticstrictures,endoscopic ultrasound-guided tissue acquisition is highly accurate and has become the diagnostic mainstay.Incontrast,the diagnosis of perihilar strictures remains a challenge.Similarly,the drainage of extrahepatic strictures tends tobe more straightforward and safer and less controversial than that of perihilar strictures.Recent evidence has providedsome clarity in multiple important areas pertaining to biliary strictures,whereas several remaining controversies requireadditional research.The goal of this guideline is to provide practicing clinicians with the most evidence-based guidance onthe approach to patients with extrahepatic and perihilar strictures,focusing on diagnosis and drainage.KEYWORDS:biliary strictures:obstructive jaundice:extrahepatic strictures:perihiliar strictures:endoscopic ultrasound:guidelineAm J Gastroenterol 2023;118:405-426.https//doiorg/10.14309/ajg.0000000000002190:published online January 17,2023INTRODUCTIONstrictures related to primary sclerosing cholangitis (PSC)is cov-A biliary stricture is an abnomal narrowing in the ductal drainageered in a separate American College of Gastroenterology(ACG)system of theliver.Theseoften result in clinically and physiologicallyguideline dedicated to this condition (1).Finally,we do not ad-relevant obstruction to the flow of bile but may not cause symptomsdress surgical or oncological care of malignant strictures,exceptor abnomal liver tests early in their course.There are many etiol-where there are endoscopic implications.ogies of biliary stricture,the most common and ominous of which isRecognizing the potential influence of commercial and in-malignancy,either primary or metastatic.The 2 principal manage-tellectual conflict of interest on the guideline development pro-ment priorities in the patient with a biliary stricture are diagnosis andcess,recommendations in this document were made by a diversedrainage-specifically,the confimmation or exclusion of malignancygroup of authors using a systematic process that involved struc-and the restoration of flow
