The week in GI, filtered to what is worth knowing.

DIAGNOSIS: Use fecal calprotectin (cutoff >50-100 μg/g) to differentiate inflammatory from noninflammatory disease OF THE COLON (strong, moderate). Ileocolonoscopy with biopsies for suspected CD; biopsy uninvolved mucosa to define histologic extent; small bowel imaging is part of the initial workup (key concepts, ungraded). CT enterography is comparable to MR enterography for small bowel detection; MRE should be used PREFERENTIALLY in patients younger than 35 years and where serial examinations are likely, because of radiation avoidance, MRE is not a blanket first choice. Intestinal ultrasound is a radiation-free ADJUNCT to diagnosis and to monitoring treatment response (key concept, ungraded, not a graded recommendation). Perform routine endoscopic CRC surveillance in Crohn's colitis (strong, moderate). MILD-TO-MODERATE / LOWER PROGRESSION RISK: Recommend AGAINST oral mesalamine for induction or maintenance (strong, moderate); sulfasalazine should be considered ONLY for symptomatic mild COLONIC CD (key concept). Controlled ileal-release budesonide 9 mg daily for induction of symptomatic remission in mildly-to-moderately active ileocecal CD (strong, moderate), but recommend AGAINST ileal-release budesonide for MAINTENANCE (strong, low). MODERATE-TO-SEVERE / HIGHER RISK: SUGGEST AGAINST requiring failure of conventional therapy before initiating advanced therapy (conditional, LOW, a permission to skip step-up, not a mandate to start advanced therapy upfront). Oral corticosteroids for short-term induction only (strong, low). Recommend AGAINST azathioprine 1.5-2.5 mg/kg/d and 6-mercaptopurine 0.75-1.5 mg/kg/d for INDUCTION (strong, moderate), but SUGGEST the same agents and doses for MAINTENANCE after corticosteroid-induced remission (conditional, low). Check TPMT before starting azathioprine/6-MP (strong, low); measure NUDT15 variants in patients of East Asian ancestry and TPMT variants in all patients prior to thiopurine initiation (strong, moderate). Methotrexate up to 25 mg weekly IM/SC for maintenance after corticosteroid induction (conditional, low). Anti-TNF agents (IV infliximab, SC adalimumab, SC certolizumab pegol) for induction and maintenance (strong, moderate). Recommend COMBINATION IV infliximab + thiopurine over either agent alone in patients naive to both (strong, moderate). Vedolizumab IV for induction and maintenance of symptomatic remission (strong, moderate). Ustekinumab (strong, moderate); risankizumab (strong, moderate), and risankizumab over ustekinumab in prior anti-TNF exposure (conditional, low); mirikizumab (strong, moderate); guselkumab IV-then-SC or all-SC (strong, moderate). Upadacitinib for induction and maintenance in patients PREVIOUSLY EXPOSED TO ANTI-TNF (strong, moderate), the ACG does not endorse it as a first-line biologic-naive option. SC infliximab and SC vedolizumab are maintenance options in responders to IV induction (strong, moderate). PERIANAL FISTULIZING: infliximab for induction (strong, moderate); adalimumab (conditional, low); antibiotics added to infliximab or adalimumab (conditional, very low); vedolizumab, ustekinumab, upadacitinib each (conditional, VERY LOW). Drain perianal abscesses and place setons before escalating advanced therapy (key concept). POST-OPERATIVE: endoscopic assessment at 6-12 months after surgically induced remission over no monitoring (conditional, moderate); in LOW post-op recurrence risk, continued observation rather than immediate medical therapy (conditional, very low); imidazole antibiotics (metronidazole) 1-2 g/d after small intestinal resection (conditional, low); in HIGH-risk CD, anti-TNF to prevent endoscopic recurrence (STRONG, moderate) and vedolizumab (CONDITIONAL, low), these two are not co-equal. SURGERY/ABSCESS: intra-abdominal abscess >2 cm should be treated with antibiotics plus a drainage procedure, and immunosuppression HELD until drainage is achieved (conditional, low). DISEASE MODIFIERS: counsel active smokers to quit; use NSAIDs with caution; assess stress, depression and anxiety as part of comprehensive care (key concepts).

DIAGNOSIS: Use fecal calprotectin (cutoff >50-100 μg/g) to differentiate inflammatory from noninflammatory disease OF THE COLON (strong, moderate). Ileocolonoscopy with biopsies for suspected CD; biopsy uninvolved mucosa to define histologic extent; small bowel imaging is part of the initial workup (key concepts, ungraded). CT enterography is comparable to MR enterography for small bowel detection; MRE should be used PREFERENTIALLY in patients younger than 35 years and where serial examinations are likely, because of radiation avoidance, MRE is not a blanket first choice. Intestinal ultrasound is a radiation-free ADJUNCT to diagnosis and to monitoring treatment response (key concept, ungraded, not a graded recommendation). Perform routine endoscopic CRC surveillance in Crohn's colitis (strong, moderate). MILD-TO-MODERATE / LOWER PROGRESSION RISK: Recommend AGAINST oral mesalamine for induction or maintenance (strong, moderate); sulfasalazine should be considered ONLY for symptomatic mild COLONIC CD (key concept). Controlled ileal-release budesonide 9 mg daily for induction of symptomatic remission in mildly-to-moderately active ileocecal CD (strong, moderate), but recommend AGAINST ileal-release budesonide for MAINTENANCE (strong, low). MODERATE-TO-SEVERE / HIGHER RISK: SUGGEST AGAINST requiring failure of conventional therapy before initiating advanced therapy (conditional, LOW, a permission to skip step-up, not a mandate to start advanced therapy upfront). Oral corticosteroids for short-term induction only (strong, low). Recommend AGAINST azathioprine 1.5-2.5 mg/kg/d and 6-mercaptopurine 0.75-1.5 mg/kg/d for INDUCTION (strong, moderate), but SUGGEST the same agents and doses for MAINTENANCE after corticosteroid-induced remission (conditional, low). Check TPMT before starting azathioprine/6-MP (strong, low); measure NUDT15 variants in patients of East Asian ancestry and TPMT variants in all patients prior to thiopurine initiation (strong, moderate). Methotrexate up to 25 mg weekly IM/SC for maintenance after corticosteroid induction (conditional, low). Anti-TNF agents (IV infliximab, SC adalimumab, SC certolizumab pegol) for induction and maintenance (strong, moderate). Recommend COMBINATION IV infliximab + thiopurine over either agent alone in patients naive to both (strong, moderate). Vedolizumab IV for induction and maintenance of symptomatic remission (strong, moderate). Ustekinumab (strong, moderate); risankizumab (strong, moderate), and risankizumab over ustekinumab in prior anti-TNF exposure (conditional, low); mirikizumab (strong, moderate); guselkumab IV-then-SC or all-SC (strong, moderate). Upadacitinib for induction and maintenance in patients PREVIOUSLY EXPOSED TO ANTI-TNF (strong, moderate), the ACG does not endorse it as a first-line biologic-naive option. SC infliximab and SC vedolizumab are maintenance options in responders to IV induction (strong, moderate). PERIANAL FISTULIZING: infliximab for induction (strong, moderate); adalimumab (conditional, low); antibiotics added to infliximab or adalimumab (conditional, very low); vedolizumab, ustekinumab, upadacitinib each (conditional, VERY LOW). Drain perianal abscesses and place setons before escalating advanced therapy (key concept). POST-OPERATIVE: endoscopic assessment at 6-12 months after surgically induced remission over no monitoring (conditional, moderate); in LOW post-op recurrence risk, continued observation rather than immediate medical therapy (conditional, very low); imidazole antibiotics (metronidazole) 1-2 g/d after small intestinal resection (conditional, low); in HIGH-risk CD, anti-TNF to prevent endoscopic recurrence (STRONG, moderate) and vedolizumab (CONDITIONAL, low), these two are not co-equal. SURGERY/ABSCESS: intra-abdominal abscess >2 cm should be treated with antibiotics plus a drainage procedure, and immunosuppression HELD until drainage is achieved (conditional, low). DISEASE MODIFIERS: counsel active smokers to quit; use NSAIDs with caution; assess stress, depression and anxiety as part of comprehensive care (key concepts).

DIAGNOSIS: Use fecal calprotectin (cutoff >50-100 μg/g) to differentiate inflammatory from noninflammatory disease OF THE COLON (strong, moderate). Ileocolonoscopy with biopsies for suspected CD; biopsy uninvolved mucosa to define histologic extent; small bowel imaging is part of the initial workup (key concepts, ungraded). CT enterography is comparable to MR enterography for small bowel detection; MRE should be used PREFERENTIALLY in patients younger than 35 years and where serial examinations are likely, because of radiation avoidance, MRE is not a blanket first choice. Intestinal ultrasound is a radiation-free ADJUNCT to diagnosis and to monitoring treatment response (key concept, ungraded, not a graded recommendation). Perform routine endoscopic CRC surveillance in Crohn's colitis (strong, moderate). MILD-TO-MODERATE / LOWER PROGRESSION RISK: Recommend AGAINST oral mesalamine for induction or maintenance (strong, moderate); sulfasalazine should be considered ONLY for symptomatic mild COLONIC CD (key concept). Controlled ileal-release budesonide 9 mg daily for induction of symptomatic remission in mildly-to-moderately active ileocecal CD (strong, moderate), but recommend AGAINST ileal-release budesonide for MAINTENANCE (strong, low). MODERATE-TO-SEVERE / HIGHER RISK: SUGGEST AGAINST requiring failure of conventional therapy before initiating advanced therapy (conditional, LOW, a permission to skip step-up, not a mandate to start advanced therapy upfront). Oral corticosteroids for short-term induction only (strong, low). Recommend AGAINST azathioprine 1.5-2.5 mg/kg/d and 6-mercaptopurine 0.75-1.5 mg/kg/d for INDUCTION (strong, moderate), but SUGGEST the same agents and doses for MAINTENANCE after corticosteroid-induced remission (conditional, low). Check TPMT before starting azathioprine/6-MP (strong, low); measure NUDT15 variants in patients of East Asian ancestry and TPMT variants in all patients prior to thiopurine initiation (strong, moderate). Methotrexate up to 25 mg weekly IM/SC for maintenance after corticosteroid induction (conditional, low). Anti-TNF agents (IV infliximab, SC adalimumab, SC certolizumab pegol) for induction and maintenance (strong, moderate). Recommend COMBINATION IV infliximab + thiopurine over either agent alone in patients naive to both (strong, moderate). Vedolizumab IV for induction and maintenance of symptomatic remission (strong, moderate). Ustekinumab (strong, moderate); risankizumab (strong, moderate), and risankizumab over ustekinumab in prior anti-TNF exposure (conditional, low); mirikizumab (strong, moderate); guselkumab IV-then-SC or all-SC (strong, moderate). Upadacitinib for induction and maintenance in patients PREVIOUSLY EXPOSED TO ANTI-TNF (strong, moderate), the ACG does not endorse it as a first-line biologic-naive option. SC infliximab and SC vedolizumab are maintenance options in responders to IV induction (strong, moderate). PERIANAL FISTULIZING: infliximab for induction (strong, moderate); adalimumab (conditional, low); antibiotics added to infliximab or adalimumab (conditional, very low); vedolizumab, ustekinumab, upadacitinib each (conditional, VERY LOW). Drain perianal abscesses and place setons before escalating advanced therapy (key concept). POST-OPERATIVE: endoscopic assessment at 6-12 months after surgically induced remission over no monitoring (conditional, moderate); in LOW post-op recurrence risk, continued observation rather than immediate medical therapy (conditional, very low); imidazole antibiotics (metronidazole) 1-2 g/d after small intestinal resection (conditional, low); in HIGH-risk CD, anti-TNF to prevent endoscopic recurrence (STRONG, moderate) and vedolizumab (CONDITIONAL, low), these two are not co-equal. SURGERY/ABSCESS: intra-abdominal abscess >2 cm should be treated with antibiotics plus a drainage procedure, and immunosuppression HELD until drainage is achieved (conditional, low). DISEASE MODIFIERS: counsel active smokers to quit; use NSAIDs with caution; assess stress, depression and anxiety as part of comprehensive care (key concepts).

Diagnose MASLD by hepatic steatosis on imaging (or biopsy) plus at least one cardiometabolic criterion and exclusion of competing etiologies (significant alcohol use, other liver disease), then risk-stratify fibrosis using a sequential non-invasive approach: FIB-4 first, followed by a second-line imaging-based test (VCTE, MRE, or ELF) for indeterminate/high-risk FIB-4, with liver biopsy reserved for discordant or unclear cases. Lifestyle modification (≥7-10% weight loss, Mediterranean diet, exercise) remains the foundation for all patients. For adults with MASH and F2-F3 fibrosis identified by non-invasive tests (VCTE 8-15 kPa, MRE 3.1-4.4 kPa, or ELF 9.2-10.5) rather than biopsy, AASLD now gives dedicated, updated practice guidance on both FDA-approved pharmacotherapies: resmetirom (Oct 2024 update) and semaglutide 2.4mg/week subcutaneous (Nov 2025 update, following August 2025 accelerated FDA approval based on ESSENCE trial data: 62.9% vs 34.3% MASH resolution without fibrosis worsening; 36.8% vs 22.4% ≥1-stage fibrosis improvement). Pioglitazone or vitamin E remain options per the 2023 base guidance. Manage cardiometabolic risk with statins for ASCVD reduction plus glycemic and blood-pressure control; for semaglutide specifically, routine hepatic panels are recommended only as clinically indicated (no discontinuations for LFT elevation in ESSENCE), with monitoring for GI adverse effects and rare risks (AKI, gallbladder disease, pancreatitis, thyroid C-cell tumors, retinopathy progression, lean mass loss). HCC surveillance with ultrasound and AFP every 6 months remains indicated only if cirrhosis is present.

Diagnose MASLD by hepatic steatosis on imaging (or biopsy) plus at least one cardiometabolic criterion and exclusion of competing etiologies (significant alcohol use, other liver disease), then risk-stratify fibrosis using a sequential non-invasive approach: FIB-4 first, followed by a second-line imaging-based test (VCTE, MRE, or ELF) for indeterminate/high-risk FIB-4, with liver biopsy reserved for discordant or unclear cases. Lifestyle modification (≥7-10% weight loss, Mediterranean diet, exercise) remains the foundation for all patients. For adults with MASH and F2-F3 fibrosis identified by non-invasive tests (VCTE 8-15 kPa, MRE 3.1-4.4 kPa, or ELF 9.2-10.5) rather than biopsy, AASLD now gives dedicated, updated practice guidance on both FDA-approved pharmacotherapies: resmetirom (Oct 2024 update) and semaglutide 2.4mg/week subcutaneous (Nov 2025 update, following August 2025 accelerated FDA approval based on ESSENCE trial data: 62.9% vs 34.3% MASH resolution without fibrosis worsening; 36.8% vs 22.4% ≥1-stage fibrosis improvement). Pioglitazone or vitamin E remain options per the 2023 base guidance. Manage cardiometabolic risk with statins for ASCVD reduction plus glycemic and blood-pressure control; for semaglutide specifically, routine hepatic panels are recommended only as clinically indicated (no discontinuations for LFT elevation in ESSENCE), with monitoring for GI adverse effects and rare risks (AKI, gallbladder disease, pancreatitis, thyroid C-cell tumors, retinopathy progression, lean mass loss). HCC surveillance with ultrasound and AFP every 6 months remains indicated only if cirrhosis is present.

Diagnose MASLD by hepatic steatosis on imaging (or biopsy) plus at least one cardiometabolic criterion and exclusion of competing etiologies (significant alcohol use, other liver disease), then risk-stratify fibrosis using a sequential non-invasive approach: FIB-4 first, followed by a second-line imaging-based test (VCTE, MRE, or ELF) for indeterminate/high-risk FIB-4, with liver biopsy reserved for discordant or unclear cases. Lifestyle modification (≥7-10% weight loss, Mediterranean diet, exercise) remains the foundation for all patients. For adults with MASH and F2-F3 fibrosis identified by non-invasive tests (VCTE 8-15 kPa, MRE 3.1-4.4 kPa, or ELF 9.2-10.5) rather than biopsy, AASLD now gives dedicated, updated practice guidance on both FDA-approved pharmacotherapies: resmetirom (Oct 2024 update) and semaglutide 2.4mg/week subcutaneous (Nov 2025 update, following August 2025 accelerated FDA approval based on ESSENCE trial data: 62.9% vs 34.3% MASH resolution without fibrosis worsening; 36.8% vs 22.4% ≥1-stage fibrosis improvement). Pioglitazone or vitamin E remain options per the 2023 base guidance. Manage cardiometabolic risk with statins for ASCVD reduction plus glycemic and blood-pressure control; for semaglutide specifically, routine hepatic panels are recommended only as clinically indicated (no discontinuations for LFT elevation in ESSENCE), with monitoring for GI adverse effects and rare risks (AKI, gallbladder disease, pancreatitis, thyroid C-cell tumors, retinopathy progression, lean mass loss). HCC surveillance with ultrasound and AFP every 6 months remains indicated only if cirrhosis is present.

Per the 2024 ADQI-ICA joint consensus (which updates the 2015 ICA-AKI criteria referenced in AASLD 2021), in a patient with cirrhosis and ascites: DIAGNOSE HRS-AKI when all of (a) cirrhosis with ascites; (b) AKI by KDIGO/ICA criteria, serum creatinine rise ≥0.3 mg/dL (26.5 µmol/L) within 48h or ≥50% from a baseline known or presumed within the prior 7 days, and/or urine output ≤0.5 mL/kg/h for ≥6h (strong recommendation, grade A); (c) absence of improvement in serum creatinine and/or urine output within 24h following adequate volume resuscitation WHEN CLINICALLY INDICATED, the consensus recommends AGAINST systematic 48h albumin administration as a diagnostic requisite (strong recommendation, grade D), and only where volume status is equivocal is a single fluid challenge (250-500 mL crystalloid, or 1-1.5 g/kg of 20-25% albumin) assessed within 24h; and (d) absence of strong evidence for an alternative primary cause of AKI (e.g., septic shock requiring vasopressors, acute glomerular injury, obstruction, or nephrotoxin-induced AKI) (not graded). HRS-AKI is a phenotype specific to advanced cirrhosis and ascites: coexisting CKD, tubular injury or proteinuria do NOT exclude it, and it may coexist with, or be superimposed on, other AKI etiologies rather than requiring pure exclusion. TREAT: immediately on diagnosis start a vasoconstrictor plus 20-25% albumin (strong recommendation, grade A). Terlipressin is first-line, continuous IV infusion 2-12 mg/day, titrated up by ≥2 mg/day every 24h to a maximum 12 mg/day if serum creatinine has not fallen ≥25%; or IV bolus 1-2 mg every 6h, escalated from 1 mg to 2 mg every 6h on that same ≥25% serum-creatinine response threshold, with the 12 mg/day maximum applying only to continuous infusion and not to bolus dosing. If terlipressin is unavailable or contraindicated, norepinephrine (continuous infusion 0.5-3 mg/h, up-titrated 0.5 mg/h every 4h to raise MAP ≥10 mmHg; requires ICU care and a central line) may be more appropriate. Midodrine 7.5-15 mg PO every 8h plus octreotide 100-200 µg SC every 8h with albumin is third-line, considered only if terlipressin is contraindicated AND transfer to ICU for norepinephrine is not possible. Give 20-25% albumin 20-40 g/day with any vasoconstrictor, adjusted daily to volume status and withheld for fluid overload/pulmonary edema. Discontinue vasoconstrictors when serum creatinine returns to within 0.3 mg/dL of baseline, for a severe adverse reaction, if kidney function does not improve after 48h at maximum tolerated dose, if RRT is indicated, or at a maximum of 14 days of therapy (strong recommendation, grade B). Initiation of RRT should be individualized to clinical context and anticipated or observed life-threatening AKI-related complications (best-practice statement) rather than framed strictly as a transplant-bridge measure. Recommend expedited evaluation for liver transplantation following an episode of AKI (best-practice statement); LT in selected patients is the definitive treatment for HRS-AKI regardless of vasoconstrictor response (strong recommendation, grade A), with vasoconstrictors serving as a bridge to transplantation or renal recovery rather than a cure.

Diagnose acute pancreatitis (AP) by the Atlanta criteria (2 of 3: characteristic epigastric/LUQ pain, lipase or amylase >3x ULN [lipase preferred for specificity/duration], or characteristic imaging). ACG 2024 stratifies severity risk using SIRS on admission plus bedside risk factors, rising/elevated BUN, rising/elevated hematocrit (>44), obesity (BMI>30), extrapancreatic fluid collections/pleural effusion/infiltrates, altered mental status, and older age/comorbidities, rather than mandating a formal BISAP or APACHE II composite score. Give moderately aggressive lactated Ringer's, most important in the first 6-12 hours, reassessing volume status/BUN/HCT at 6 hours (further aggressive hydration has little added benefit after 24-48h). Start oral low-fat solid food within 24-48h as tolerated in mild disease; if enteral feeding is needed for moderately severe/severe disease, prefer nasogastric over nasojejunal with small-peptide/medium-chain-triglyceride formula and continuous (not bolus/cyclic) feeding; avoid parenteral nutrition if possible. Do not give prophylactic antibiotics, even in severe disease or sterile necrosis; reserve antibiotics for suspected infected necrosis (typically arising 10-14 days in), and choose agents that penetrate pancreatic necrosis while together covering both gut-derived gram-negative enterics and anaerobes, a carbapenem supplies this as monotherapy, whereas a fluoroquinolone or a third-or-higher-generation cephalosporin must be combined with metronidazole; metronidazole alone (anaerobic cover only), or a cephalosporin or a quinolone alone, does not adequately treat infected necrosis. Perform cholecystectomy preferably before discharge for mild acute biliary pancreatitis, and after a second unexplained AP episode even without identified gallstones; reserve ERCP within 24h for AP complicated by cholangitis, with rectal indomethacin +/- pancreatic duct stent and periprocedural hydration to reduce post-ERCP pancreatitis risk. Check triglycerides when gallstones/alcohol are absent (>1000 mg/dL supports a hypertriglyceridemia etiology). For stable pancreatic necrosis, defer surgical, radiological, or endoscopic intervention 4-6 weeks to allow walling-off (step-up approach).

Perform individual gastric risk assessment and staging of precancerous conditions at first-time gastroscopy, irrespective of the patient's country of origin. Use high quality endoscopy with virtual chromoendoscopy (VCE), after proper training, for screening, diagnosis and staging of atrophy and intestinal metaplasia and after endoscopic therapy; VCE guides the biopsy site, with random biopsies taken only when there are no endoscopically suspected changes. Take biopsies from at least two topographic sites, 2 from the antrum/incisura and 2 from the corpus, VCE-guided, in two separate, clearly labeled vials; an additional incisura biopsy is optional, not required. Stage with validated endoscopic classifications of atrophy (e.g. Kimura-Takemoto) or intestinal metaplasia (e.g. EGGIM) to stratify gastric cancer risk (suggestion, weaker than the biopsy recommendation). Follow up patients with extensive endoscopic changes (Kimura C3+ or EGGIM 5+) OR an advanced histological stage that reaches OLGA/OLGIM III/IV, severe atrophy or intestinal metaplasia and/or significant changes in both antrum and corpus rising to stage III/IV, not any intestinal metaplasia or any antrum-plus-corpus involvement on its own, with high quality endoscopy every 3 years, irrespective of country of origin (strong recommendation, moderate quality). Propose NO surveillance for patients with mild to moderate atrophy or intestinal metaplasia restricted to the antrum, in the absence of endoscopic signs of extensive lesions or other risk factors (family history of gastric cancer, incomplete intestinal metaplasia, persistent H. pylori infection), the guideline states this group constitutes most individuals found in clinical practice. Eradicate H. pylori in all patients with precancerous conditions and after endoscopic or surgical therapy. Discontinue or do not start gastric cancer screening or surveillance in asymptomatic individuals over 80, and weigh comorbidities when planning treatment of superficial lesions. Advise smoking cessation; low-dose daily aspirin may be considered for gastric cancer prevention only in selected individuals already at high cardiovascular risk. For visible neoplasia, use ESD for differentiated lesions clinically staged as dysplastic (low or high grade) or intramucosal carcinoma (any size if not ulcerated, or ≤30 mm if ulcerated), with EMR an alternative for Paris 0-IIa lesions ≤10 mm with low likelihood of malignancy. At the population level, endoscopic screening is suggested every 2-3 years in high-risk regions (age-standardized rate >20 per 100,000 person-years), every 5 years in intermediate-risk regions (ASR 10-20) only if cost-effectiveness has been proven, and not at all in low-risk regions (ASR <10).

Distinguish benign from malignant biliary strictures using cross-sectional imaging (MRI/MRCP preferred over contrast-enhanced CT) plus laboratory tests, interpreting CA19-9 after biliary decompression and never relying on tumor markers alone; check serum IgG4 when IgG4-related sclerosing cholangitis is suspected (HISORt criteria). Per the ESGE 2024 diagnostic work-up guideline, tissue-acquisition strategy now branches by stricture location rather than following one linear sequence: for DISTAL extrahepatic strictures with jaundice and no pancreatic mass, combined same-session EUS-guided tissue acquisition (EUS-TA, end-cutting FNB needle) plus ERCP-based tissue acquisition (standard brush cytology plus fluoroscopy-guided biopsy) is the strongly preferred first-line approach; for PERIHILAR strictures, obtain brush cytology plus fluoroscopy-guided biopsy at index ERCP, escalate indeterminate strictures to cholangioscopy-guided biopsy (with intraductal ultrasound/confocal laser endomicroscopy selectively), and reserve EUS-TA for cases where ERCP-based sampling is insufficient and curative resection is not feasible and/or extraluminal disease is accessible; escalate any positive or indeterminate feature to multidisciplinary tumor board. Manage benign anastomotic and chronic-pancreatitis strictures with a fully-covered self-expanding metal stent for 6-12 months (multiple plastic stents when FCSEMS is contraindicated, hepaticojejunostomy if refractory). Treat cholangitis with biliary obstruction as an indication for urgent biliary drainage, but do not instrument every obstructed sector: for hilar or multisegmental strictures (Bismuth II-IV), ESGE suggests draining ≥50% of the liver volume and avoiding opacification of biliary ducts that will not be drained (weak recommendation, low-quality evidence), because post-ERCP cholangitis frequently complicates injection of obstructed ducts that are not subsequently drained, whereas drainage of >50% of liver volume is associated with less cholangitis and longer survival; ESGE suggests antibiotic prophylaxis before biliary stenting in selected patients (e.g., immunocompromised patients, expected incomplete biliary drainage; weak recommendation, moderate-quality evidence), with a full antibiotic course if adequate drainage is not achieved during the procedure. Direct etiology-specific care for Strasberg bile-duct injuries, post-transplant strictures (ASGE 2023: ERCP preferred over PTBD, covered SEMS preferred over multiple plastic stents), IgG4-sclerosing cholangitis, Mirizzi syndrome, and choledochal cysts.

Address the specific underlying cause of persistent or new post-cholecystectomy symptoms after narrowing the heterogeneous differential (retained/CBD stone, sphincter of Oddi dysfunction, bile leak/duct injury, bile acid diarrhea, functional dyspepsia/IBS, GERD). First exclude time-sensitive early postoperative complications, bile leak/duct injury, obstructing retained/CBD stone, biliary obstruction or cholangitis, and treat red-flag features (jaundice, fever, sepsis, or early-onset/worsening pain) as warranting prompt evaluation rather than reassurance; only then reassure that most symptoms settle within 6-12 months, avoid empiric reoperation, and obtain multidisciplinary GI + HPB surgery input for refractory or atypical cases.