Gastrointestinal

Choledocholithiasis and ascending cholangitis: ERCP and antibiotics

Clinical Overview and When to Suspect Choledocholithiasis and Cholangitis

— Present in ~10–20% of patients with symptomatic cholelithiasis

— May be silent, cause biliary colic, obstructive jaundice, gallstone pancreatitis, or progress to cholangitis

— Most common etiology in the US: CBD stone obstruction (~80%); others include malignant strictures (pancreatic head, cholangiocarcinoma), benign strictures, post-ERCP, indwelling stents, parasites (Clonorchis, Ascaris) abroad

— Organisms: E. coli, Klebsiella, Enterobacter, Enterococcus, anaerobes (Bacteroides, Clostridium) particularly with prior biliary instrumentation

— RUQ pain + jaundice + fever (Charcot triad) → cholangitis until proven otherwise

— Add hypotension + altered mental status = Reynolds pentad → severe (suppurative) cholangitis, ICU-level

— Post-cholecystectomy patient with new jaundice, elevated alk phos/GGT, dilated CBD on US → retained or recurrent CBD stone

— Gallstone pancreatitis with persistent cholestasis after 48 hours → suspect impacted CBD stone

— Elderly patient with vague abdominal pain, low-grade fever, and isolated cholestatic LFTs → atypical cholangitis (triad present in only ~50–70%)

Board pearl: In any septic patient with cholestatic LFTs (alk phos and direct bilirubin disproportionately elevated vs AST/ALT), think ascending cholangitis and move toward ERCP within 24–48 hours, urgent (<12 h) if Tokyo Grade III.

Choledocholithiasis = stone(s) in the common bile duct (CBD), most often from migration of gallbladder stones through the cystic duct

Acute (ascending) cholangitis = bacterial infection of an obstructed biliary tree, a surgical/endoscopic emergency

When to suspect on Step 3:

Pathophysiology pearl: stasis + increased intraductal pressure (>20 cm H₂O) allows cholangiovenous and cholangiolymphatic reflux of bacteria → bacteremia and sepsis; biliary drainage is therapeutic, antibiotics alone are insufficient.

Presentation Patterns and Key History

— Full triad in only 50–70% of cases; fever is most common single feature

— Reynolds pentad adds hypotension and confusion → suppurative cholangitis, mortality up to 20–30% without urgent drainage

— Episodic RUQ or epigastric pain radiating to right shoulder/scapula, lasting 30 min to several hours

— Postprandial, often after fatty meal; nausea, vomiting

— Pruritus, dark urine, pale (acholic) stools indicate sustained obstruction

— May be entirely asymptomatic and discovered on imaging

— Prior gallstones, biliary colic, or cholecystectomy (retained vs recurrent stones)

— Prior ERCP, biliary stents (indwelling stents are a major risk for recurrent cholangitis and unusual organisms)

— Recent gallstone pancreatitis

— Weight loss, painless jaundice → think malignant obstruction, not stone

— Travel to East/Southeast Asia → recurrent pyogenic (Oriental) cholangitis, Clonorchis sinensis

— HIV/immunosuppression → AIDS cholangiopathy (CMV, Cryptosporidium)

— Inflammatory bowel disease → primary sclerosing cholangitis with dominant stricture

— Fever >38°C with jaundice

— RUQ pain with rigors

— Confusion, hypotension, oliguria

— Rising bilirubin >4 mg/dL with cholestatic pattern

Key distinction: Biliary colic = pain only, normal labs, no fever. Acute cholecystitis = pain + fever + Murphy sign, usually normal bilirubin. Choledocholithiasis = pain + jaundice, no fever. Cholangitis = pain + jaundice + fever ± sepsis. Differentiating these drives the next step: cholecystectomy alone vs ERCP first vs ERCP urgently.

Step 3 management: Outpatient triage of new painless jaundice with cholestatic LFTs → urgent (not emergent) RUQ ultrasound; if ducts dilated and no stone seen, obtain MRCP and refer to GI; do not start empiric antibiotics without infection signs.

Classic cholangitis triad (Charcot): RUQ pain, fever/chills, jaundice

Choledocholithiasis without infection:

Key history points to elicit (Step 3 ambulatory voice):

Red flags warranting same-day evaluation:

Physical Exam Findings and Hemodynamic Assessment

— Toxic, diaphoretic, rigoring patient = cholangitis until proven otherwise

— Scleral icterus visible when total bilirubin >2.5–3 mg/dL; sublingual jaundice earlier

— Excoriations from pruritus suggest chronic cholestasis

— RUQ tenderness, often without peritoneal signs (cholangitis pain is usually less localized than cholecystitis)

— Murphy sign typically absent in pure choledocholithiasis/cholangitis (gallbladder not inflamed); if positive, consider concurrent cholecystitis

— Courvoisier sign = palpable, nontender, distended gallbladder with jaundice → suggests malignant distal obstruction (pancreatic head cancer, cholangiocarcinoma), not stone disease

— Hepatomegaly mild and tender

— Absence of peritonitis; rebound/guarding should prompt search for perforation, gangrenous cholecystitis, or alternative diagnosis

— Temperature >39°C or rigors → systemic inflammation

— SBP <100 mmHg, MAP <65, or vasopressor requirement → Grade III (severe)

— Heart rate >90, RR >20, leukocytosis or leukopenia → SIRS criteria

— Altered mental status (GCS drop) → Grade III

— Urine output <0.5 mL/kg/hr → renal dysfunction, Grade III

— Cool extremities, mottling, lactate >2 → septic shock

— Jaundice, excoriations, xanthelasma (chronic cholestasis)

— Look for surgical scars (prior cholecystectomy → suspect retained CBD stone or biliary stricture)

CCS pearl: On the CCS case, when the stem mentions fever + jaundice + hypotension, immediately order: two large-bore IVs, IVF bolus (30 mL/kg crystalloid), blood cultures ×2, CBC, CMP, lipase, lactate, coags, type and screen, broad-spectrum IV antibiotics, NPO, urgent GI/ERCP consult, ICU evaluation, and obtain RUQ US while resuscitating. Don't wait for imaging to start antibiotics.

Board pearl: Painless jaundice + palpable gallbladder = think tumor, not stone (Courvoisier law).

General appearance:

Abdominal exam:

Hemodynamic assessment (drives Tokyo severity grading):

Skin/extra-abdominal:

Diagnostic Workup — Initial Labs and Imaging

— CBC: leukocytosis with left shift; leukopenia is an ominous sepsis marker

— CMP/LFTs — cholestatic pattern:

— Alkaline phosphatase elevated (often 2–5× ULN)

— GGT elevated (confirms hepatobiliary origin of alk phos)

— Direct (conjugated) hyperbilirubinemia; total bili often 2–10 mg/dL

— AST/ALT may spike acutely with stone impaction (transaminitis up to 500–1000), then fall as cholestasis predominates ("flip" pattern)

— Lipase: rule out concurrent gallstone pancreatitis

— Coagulation (PT/INR): prolonged with prolonged cholestasis (vitamin K malabsorption) or sepsis-induced coagulopathy

— Lactate, procalcitonin: sepsis severity

— Blood cultures ×2 before antibiotics (positive in 20–40% of cholangitis)

— Type and screen pre-procedure

— High sensitivity for gallstones (>95%) and CBD dilation (>6 mm, or >8–10 mm post-cholecystectomy)

— Sensitivity for CBD stones themselves is only ~25–60% (duodenal gas obscures distal CBD)

— Findings supporting choledocholithiasis: dilated CBD, visible CBD stone, intrahepatic ductal dilation

— Findings of acute cholecystitis (wall >3 mm, pericholecystic fluid, sonographic Murphy) if concurrent

— Abdominal CT (with IV contrast if renal function permits): better for complications (abscess, pneumobilia, emphysematous cholecystitis, malignancy), but only ~75% sensitive for stones (most are radiolucent cholesterol stones)

— Use CT when diagnosis unclear, suspecting tumor or perforation

Step 3 management: A patient with classic Charcot triad and dilated CBD on US does not need MRCP before therapy — proceed to ERCP, which is both diagnostic and therapeutic. MRCP is reserved for intermediate-probability cases to avoid unnecessary ERCP.

Board pearl: Alk phos >3× ULN + dilated CBD on US = high probability of CBD stone per ASGE criteria → go straight to ERCP.

Laboratory panel (order all together):

Right upper quadrant ultrasound — FIRST imaging study:

Plain films and CT:

ECG: in elderly or cardiac patients before procedural sedation/ERCP

Diagnostic Workup — Advanced or Confirmatory Studies

— High probability (any one): CBD stone visualized on US/CT, clinical ascending cholangitis, total bilirubin >4 mg/dL with dilated CBD → proceed directly to ERCP

— Intermediate probability: abnormal LFTs, age >55, or dilated CBD alone → MRCP or EUS before committing to ERCP

— Low probability: normal LFTs and normal CBD diameter → proceed to laparoscopic cholecystectomy ± intraoperative cholangiogram (IOC)

— Noninvasive, no radiation, no contrast (typically)

— Sensitivity ~85–95%, specificity >90% for CBD stones >5 mm

— Misses small (<5 mm) stones and sludge

— Excellent for malignant strictures, anatomic variants, primary sclerosing cholangitis

— Preferred in pregnancy when imaging beyond US is needed

— Highest sensitivity (~95%) for small CBD stones and microlithiasis

— Useful when MRCP equivocal; can be followed by ERCP in same session if stone confirmed

— Preferred over MRCP in obese patients or those with contraindications to MRI

— Performed during cholecystectomy; identifies and can clear CBD stones in one anesthetic

— Increasingly used to avoid pre-op ERCP in intermediate-risk patients

— A. Systemic inflammation: fever/chills or labs (WBC, CRP)

— B. Cholestasis: jaundice or abnormal LFTs

— C. Imaging: biliary dilation or evidence of etiology (stone, stricture, stent)

— Suspected = A + (B or C); Definite = A + B + C

Key distinction: MRCP = noninvasive imaging only; ERCP = invasive, therapeutic (stone extraction, stent, sphincterotomy) but carries 5–10% pancreatitis risk. Never do ERCP for diagnosis alone when MRCP/EUS will answer the question.

Board pearl: In gallstone pancreatitis without cholangitis, early ERCP is not routinely indicated; reserve for persistent obstruction or cholangitis.

ASGE risk stratification for CBD stones (drives next test):

Magnetic resonance cholangiopancreatography (MRCP):

Endoscopic ultrasound (EUS):

Intraoperative cholangiogram (IOC) / laparoscopic CBD exploration:

HIDA scan: not for choledocholithiasis; reserved for acalculous cholecystitis or cystic duct obstruction questions

Tokyo Guidelines (TG18) diagnostic criteria for cholangitis:

Risk Stratification and First-Line Management Logic

— Grade I (mild): responds to initial medical therapy, no organ dysfunction

— Antibiotics + elective ERCP within 24–48 hours

— Grade II (moderate): any 2 of: WBC >12 or <4, fever ≥39°C, age ≥75, total bili ≥5, albumin <0.7× lower limit

— Antibiotics + early biliary drainage within 24 hours

— Grade III (severe): organ dysfunction in any system

— Cardiovascular (pressors needed)

— Neurologic (altered mental status)

— Respiratory (PaO₂/FiO₂ <300)

— Renal (creatinine >2 or oliguria)

— Hepatic (INR >1.5)

— Hematologic (platelets <100k)

— Urgent drainage within 12 hours, ICU admission, vasopressors, source control priority

— IV crystalloid 30 mL/kg for hypotension or lactate ≥4

— Blood cultures ×2 before antibiotics, but do not delay antibiotics >1 hour

— Empiric broad-spectrum IV antibiotics

— Vasopressors (norepinephrine first-line) if MAP <65 after fluids

— Lactate trend, urine output monitoring, mental status checks

— NPO; correct coagulopathy (vitamin K, FFP) before ERCP if INR >1.5

— Reverse antiplatelets/anticoagulants per procedural bleeding risk

— Grade I → ward, IV antibiotics, ERCP next day

— Grade II → step-down or ICU, ERCP within 24 hours

— Grade III → ICU, ERCP <12 hours; if ERCP unavailable or fails → percutaneous transhepatic biliary drainage (PTBD) or surgical decompression

Step 3 management: A hypotensive, confused, jaundiced patient is Grade III cholangitis → resuscitate, broad-spectrum antibiotics, call GI for emergent ERCP, ICU bed. Never send to OR for cholecystectomy first — drain the duct first, remove the gallbladder later (interval cholecystectomy during same admission, after recovery).

Board pearl: Definitive treatment of cholangitis = biliary drainage. Antibiotics buy time; they do not cure obstruction.

Tokyo Guidelines (TG18) severity grading for acute cholangitis — drives timing of drainage:

Initial resuscitation bundle (within first hour, sepsis-style):

Triage decision tree:

Pharmacotherapy — Antibiotic Regimens

— Cover gram-negative enterics (E. coli, Klebsiella, Enterobacter), enterococci, and anaerobes (especially with biliary-enteric anastomosis, indwelling stent, or severe disease)

— Initiate within 1 hour of recognition; de-escalate based on cultures

— Continue for 4–7 days after adequate source control (drainage); longer (10–14 d) if persistent bacteremia, Enterococcus, or incomplete drainage

— Ceftriaxone 1–2 g IV daily + metronidazole 500 mg IV q8h

— Alternative: piperacillin-tazobactam 3.375 g IV q6h (covers enterococci, monotherapy)

— Cipro/levofloxacin + metronidazole in beta-lactam allergy (rising E. coli resistance — verify local antibiogram)

— Piperacillin-tazobactam or cefepime + metronidazole

— Meropenem 1 g IV q8h if ESBL risk, recent broad-spectrum antibiotic exposure, or prior resistant organisms

— Add vancomycin if MRSA risk or known VRE colonization (linezolid/daptomycin for VRE)

— Antifungal (fluconazole or echinocandin) only if Candida grown or high-risk immunosuppressed with persistent sepsis

— Enterococcus: ampicillin, pip-tazo, vancomycin (NOT cephalosporins — cephalosporins have NO enterococcal activity)

— Pseudomonas: pip-tazo, cefepime, meropenem, ciprofloxacin

— Anaerobes: metronidazole, pip-tazo, carbapenems; ceftriaxone alone does NOT cover anaerobes

— Antipyretics (acetaminophen — caution in hepatic dysfunction)

— Analgesia: avoid morphine historically (sphincter of Oddi spasm — clinically minor); use hydromorphone or fentanyl

— Antiemetics: ondansetron

— DVT prophylaxis once bleeding risk acceptable; hold prior to ERCP per endoscopy unit policy

— Vitamin K 10 mg IV/SC if INR elevated from cholestasis

Key distinction: Ceftriaxone covers gram-negatives but NOT enterococci or anaerobes — that's why metronidazole is added, and why pip-tazo is often preferred as monotherapy in sicker patients.

Board pearl: Persistent fever/bacteremia after 48–72 hours of appropriate antibiotics = inadequate source control → re-image, reassess drainage, look for abscess.

Empiric antibiotic principles:

Community-acquired, Grade I–II cholangitis:

Healthcare-associated or Grade III cholangitis, or prior biliary instrumentation/stent:

Specific organism coverage pearls:

Adjuncts:

ERCP and Procedural Management

— Technique:

— Side-viewing duodenoscope to ampulla of Vater

— Cannulate CBD, inject contrast under fluoroscopy

— Endoscopic sphincterotomy (ES) of major papilla

— Balloon or basket extraction of stones

— Mechanical lithotripsy for large/impacted stones

— Plastic or metal biliary stent placement if stones cannot be cleared, to ensure drainage and bridge to definitive therapy

— Cholangiogram confirms duct clearance

— Grade III: <12 hours (emergent)

— Grade II: <24 hours

— Grade I: 24–48 hours (next available)

— Post-ERCP pancreatitis (PEP) — most common, 3–10%; risk factors: young women, SOD, difficult cannulation, prior PEP. Prophylaxis: rectal indomethacin 100 mg pre/post-procedure, aggressive LR hydration, pancreatic duct stent in high-risk

— Bleeding (post-sphincterotomy): 1–2%

— Perforation: <1%, can be retroperitoneal

— Cholangitis: 1% (worsening with incomplete drainage)

— Cardiopulmonary from sedation

— Percutaneous transhepatic biliary drainage (PTBD) — interventional radiology, especially with hilar obstruction, post-Roux-en-Y anatomy, or failed cannulation

— EUS-guided biliary drainage (advanced centers)

— Surgical CBD exploration — last resort in unstable patient with failed endoscopic/percutaneous options

— After stone clearance and recovery, laparoscopic cholecystectomy during the same admission (within 2 weeks) prevents recurrent biliary events

— In poor surgical candidates: leave biliary stent and pursue endoscopic surveillance

— Intraoperative cholangiogram or laparoscopic CBD exploration during cholecystectomy is an alternative single-stage approach in selected patients

CCS pearl: Sequence for cholangitis: resuscitate → antibiotics → ERCP with sphincterotomy/stone extraction → interval cholecystectomy before discharge. Skipping interval cholecystectomy → ~25% recurrent biliary event within 1 year.

Board pearl: Rectal indomethacin reduces post-ERCP pancreatitis; give to high-risk patients unless contraindicated.

ERCP (endoscopic retrograde cholangiopancreatography) — gold standard for both diagnosis and treatment of choledocholithiasis and cholangitis:

Timing by Tokyo grade:

ERCP complications (consent points):

Alternative drainage when ERCP fails or anatomy precludes it:

Definitive treatment of underlying choledocholithiasis:

Special Populations — Elderly and Renal/Hepatic Impairment

— Higher mortality (5–10% vs <3% in younger)

— Atypical presentations: confusion, low-grade fever, isolated hypotension; Charcot triad in <50%

— Lower threshold for ICU and urgent ERCP

— Polypharmacy — reconcile anticoagulants, antiplatelets pre-ERCP per ASGE/AHA guidance

— Warfarin/DOACs: hold; bridge only if very high thromboembolic risk (mechanical mitral valve, recent VTE)

— Aspirin can usually be continued for sphincterotomy

— Clopidogrel/P2Y12 inhibitors: hold 5–7 days if feasible

— Sedation risk: propofol with anesthesia support preferred; avoid benzodiazepine over-sedation

— Address goals of care early — frail nonagenarian with severe cholangitis may favor PTBD/stent over surgery

— Avoid nephrotoxic contrast load: ERCP uses fluoroscopic contrast intrabiliary, minimal systemic absorption — generally safe even in CKD

— Dose-adjust antibiotics:

— Pip-tazo: reduce in CrCl <40

— Cefepime: reduce; neurotoxicity (encephalopathy, myoclonus, seizures) in renal failure — high-yield

— Meropenem: dose-reduce in CrCl <50

— Vancomycin: trough-guided or AUC-guided dosing

— Metronidazole: no renal adjustment but reduce in severe hepatic disease

— Avoid aminoglycosides when possible

— Monitor for AKI from sepsis and contrast (uncommon but possible)

— Higher procedural bleeding risk; correct INR with vitamin K first (cholestasis-related), then FFP/PCC if active bleeding; thrombocytopenia <50k → platelet transfusion before sphincterotomy (or use balloon dilation alternative)

— Adjust drug doses: avoid full-dose metronidazole in severe hepatic failure (reduce by 50%); cefoperazone/ceftriaxone caution

— Pre-existing ascites increases procedural complications

— Differentiate cholangitis from spontaneous bacterial peritonitis in cirrhotic with fever — different sites, different organisms

— MELD-based mortality risk rises sharply with bilirubin and INR; involve hepatology

Step 3 management: Elderly cholangitis patient on warfarin → hold warfarin, give vitamin K 5–10 mg IV, transfuse FFP/PCC if INR >2 and procedure urgent, proceed with ERCP — do NOT delay drainage for elective INR normalization in Grade III disease.

Board pearl: Cefepime neurotoxicity in CKD is a classic Step 3 trap — adjust the dose.

Elderly (≥75, a Tokyo Grade II criterion):

Renal impairment:

Hepatic impairment / cirrhosis:

Special Populations — Pregnancy and Pediatrics

— Cholelithiasis is common (estrogen → cholesterol supersaturation, progesterone → biliary stasis); 1–3% of pregnancies have symptomatic stones

— Choledocholithiasis and cholangitis in pregnancy are uncommon but high-risk: fetal loss up to 10–60% with maternal sepsis

— Imaging:

— RUQ ultrasound first-line (no radiation)

— MRCP without gadolinium is safe in 2nd/3rd trimester for further evaluation

— Avoid CT when possible

— ERCP in pregnancy:

— Indicated for cholangitis or impacted stone causing severe pancreatitis/obstruction

— Performed in 2nd trimester when feasible; in any trimester if life-threatening

— Minimize fluoroscopy: lead shielding over uterus, short fluoro time, no fluoro cholangiogram when possible (use aspiration/bile flow or wire-guided)

— Position in left lateral tilt to avoid IVC compression

— Fetal monitoring per OB

— Antibiotics in pregnancy:

— Safe: ceftriaxone, pip-tazo, cefepime, ampicillin, metronidazole (avoid 1st trimester if possible, though widely used)

— Avoid: fluoroquinolones (cartilage), tetracyclines (teeth/bone), aminoglycosides (ototoxicity)

— Definitive cholecystectomy:

— Best performed in 2nd trimester laparoscopically

— In 3rd trimester, may temporize with biliary stent and defer cholecystectomy postpartum

— OB-MFM co-management mandatory

— Choledocholithiasis is uncommon; consider hemolytic disease (sickle cell — pigment stones), TPN-related cholestasis, cystic fibrosis, choledochal cysts (Caroli, type I cyst), hereditary spherocytosis

— Ultrasound first; MRCP for further evaluation

— Pediatric ERCP at experienced centers; sphincterotomy techniques modified

— Choledochal cyst → surgical excision with hepaticojejunostomy (malignant degeneration risk)

— Antibiotics weight-based; same gram-negative + anaerobic principles

— Cholecystectomy after recovery, ideally same admission

Key distinction: Pregnant patient with cholangitis → don't reflexively defer ERCP. Untreated maternal sepsis kills the fetus faster than properly shielded ERCP.

Board pearl: Child with recurrent cholangitis, abdominal mass, and jaundice → think choledochal cyst (classic triad); diagnose with MRCP, treat surgically.

Pregnancy:

Pediatrics:

Complications and Adverse Outcomes

— Septic shock and multiorgan failure — leading cause of death; mortality 10–30% with delayed drainage

— Hepatic abscess (single or multiple) — fever and leukocytosis persisting after duct clearance; treat with prolonged antibiotics + percutaneous drainage

— Bacteremia with secondary seeding: endocarditis (especially in valve disease), vertebral osteomyelitis, septic emboli — Klebsiella liver abscess syndrome (Asian patients, hypermucoviscous K. pneumoniae → metastatic endophthalmitis, meningitis)

— DIC and acute kidney injury from sepsis

— Acute respiratory distress syndrome

— Acalculous cholecystitis in critically ill patients

— Secondary biliary cirrhosis with prolonged or recurrent obstruction

— Gallstone pancreatitis (concurrent in up to 25%)

— Mirizzi syndrome — stone in cystic duct/Hartmann pouch compressing CHD

— Cholecystoenteric fistula and gallstone ileus — bowel obstruction from large stone eroding into duodenum, lodging at ileocecal valve (Rigler triad on imaging: pneumobilia, SBO, ectopic stone)

— Pancreatitis (PEP): 3–10%; abdominal pain + lipase >3× ULN >24 h post-procedure; treat supportively, IV fluids

— Bleeding post-sphincterotomy: immediate or delayed up to 2 weeks; manage with repeat endoscopy, epinephrine injection, clips, or coiling

— Perforation: retroperitoneal (sphincterotomy-related) or free (scope-related); CT diagnosis; surgical or conservative management depending on grade

— Cholangitis from incomplete drainage or contaminated equipment

— Stent complications: occlusion (recurrent cholangitis), migration, duodenal perforation

— Sedation-related: aspiration, hypoxia, arrhythmia

— Recurrent CBD stones (~10–20% within 5 years, higher with retained gallbladder)

— Papillary stenosis after sphincterotomy

— Increased bacterial colonization of biliary tree post-sphincterotomy (clinically usually silent)

Step 3 management: Patient develops worsening abdominal pain, lipase 1200, 6 hours post-ERCP → post-ERCP pancreatitis; admit (if outpatient ERCP), IV LR, NPO initially then early enteral feeding, analgesia, monitor for severe pancreatitis criteria.

Board pearl: Recurrent cholangitis after stenting → suspect stent occlusion; replace it.

Complications of untreated/severe cholangitis:

Complications of obstruction itself:

Post-ERCP complications:

Long-term:

When to Escalate — ICU, Consult, and Transfer Criteria

— Vasopressor requirement after 30 mL/kg crystalloid

— Altered mental status (GCS <14 attributable to sepsis)

— Lactate >4 mmol/L or persistent >2 after resuscitation

— Respiratory failure (PaO₂/FiO₂ <300 or need for noninvasive/invasive ventilation)

— AKI with creatinine >2 or oliguria <0.5 mL/kg/hr

— DIC, platelets <100k, INR >1.5 from sepsis

— Severe metabolic acidosis

— Need for emergent ERCP under general anesthesia in unstable patient

— Gastroenterology / advanced endoscopist for urgent ERCP

— General/HPB surgery for cholecystectomy planning and as backup if ERCP fails

— Interventional radiology if PTBD may be needed (failed ERCP, hilar obstruction, altered anatomy like Roux-en-Y)

— Anesthesia for procedural support

— Critical care for ICU co-management

— Infectious disease for resistant organisms, persistent bacteremia, or unusual host

— No 24/7 ERCP availability

— Need for PTBD without IR capability

— Altered surgical anatomy (Roux-en-Y, hepaticojejunostomy)

— Suspected malignant obstruction requiring multidisciplinary HPB care

— Failed initial drainage attempt

— Pediatric or pregnant patient at non-specialized center

— Persistent shock or multiorgan failure beyond local capability

— Stabilize first (antibiotics, fluids, pressors); transfer with appropriate level of care

— Off vasopressors >24 h

— Afebrile, declining WBC

— Improving LFTs after drainage

— Stable mental status, adequate urine output, lactate normalized

CCS pearl: On the CCS, after ordering ERCP, immediately also order: ICU bed if Grade III, surgery consult for interval cholecystectomy, daily LFTs, repeat blood cultures if persistently febrile. Move the clock forward only after orders are in place; don't let the patient destabilize between screens.

Board pearl: Failed ERCP cannulation in a sick patient → PTBD by IR is the next step, not repeat ERCP attempts hours later.

ICU admission criteria (Tokyo Grade III or persistent instability):

Consultations to call immediately (parallel, not sequential):

Transfer criteria (community hospital → tertiary center):

De-escalation criteria (ICU → floor):

Key Differentials — Same-Category (Hepatobiliary/Pancreatic) Causes

— RUQ pain, fever, +Murphy sign, leukocytosis

— LFTs usually normal or mildly elevated (bili <4 unless Mirizzi)

— US: gallbladder wall thickening, pericholecystic fluid, sonographic Murphy, gallstones in neck

— Treatment: antibiotics + laparoscopic cholecystectomy within 7 days (ideally <72 h)

— Epigastric pain radiating to back, nausea, vomiting

— Lipase >3× ULN

— LFTs may show transient cholestasis; ALT >150 is 95% specific for biliary etiology

— Treatment: supportive, early enteral feeding; ERCP only if concurrent cholangitis or persistent biliary obstruction; cholecystectomy before discharge for mild pancreatitis

— Impacted stone in cystic duct/gallbladder neck compressing CHD → obstructive jaundice without primary CBD stone

— Can mimic cholangiocarcinoma; MRCP/ERCP diagnose

— Surgical management often more complex (subtotal cholecystectomy, fistula repair)

— Young male with IBD (UC), cholestatic LFTs, MRCP shows "beads on a string" multifocal strictures

— Recurrent cholangitis from dominant strictures

— Risk of cholangiocarcinoma — surveillance with MRCP and CA 19-9

— Treatment of dominant stricture: ERCP with dilation ± stent; ursodeoxycholic acid not proven to alter outcome

— Painless progressive jaundice, weight loss, palpable nontender gallbladder (Courvoisier)

— Elevated CA 19-9, CEA

— Cross-sectional imaging (CT pancreas protocol, MRI/MRCP) for mass and staging

— ERCP for tissue (brushings, intraductal biopsy) and stent for drainage

— Congenital biliary dilation; presents with jaundice, RUQ mass, recurrent cholangitis

— Classic in children/young adults; malignant degeneration risk → surgical resection

— CD4 <100, CMV/Cryptosporidium/Microsporidia

— Papillary stenosis, intrahepatic strictures on ERCP

— Treatment: ART, sphincterotomy for relief; treat underlying organism

Key distinction: Cholecystitis = gallbladder, Murphy +, bili usually normal. Cholangitis = ductal infection, jaundice prominent, no Murphy. Both can coexist.

Board pearl: Young male with UC + cholestatic LFTs → MRCP for PSC, do not assume stones.

Acute cholecystitis:

Gallstone pancreatitis:

Mirizzi syndrome:

Primary sclerosing cholangitis (PSC):

Cholangiocarcinoma / pancreatic head adenocarcinoma:

Choledochal cyst:

AIDS cholangiopathy:

Key Differentials — Other-Category Causes

— Can present with referred RUQ pain, fever, leukocytosis mimicking biliary sepsis

— No jaundice, normal LFTs; CXR clarifies

— Especially in elderly with vague abdominal complaints

— Hepatocellular pattern (AST/ALT in thousands) >> alk phos

— Risk factors: travel, sexual exposure, IVDU, raw shellfish (HAV/HEV)

— No biliary dilation on US

— Bilirubin often elevated but with hepatocellular not cholestatic pattern

— AST:ALT >2:1 in alcoholic hepatitis, both usually <500

— Drugs: amoxicillin-clavulanate (cholestatic), augmentin, anabolic steroids, OCPs, azathioprine

— No ductal dilation; consider liver biopsy when unclear

— Flank > RUQ pain, CVA tenderness, pyuria, hematuria

— No jaundice; LFTs normal

— Fever, RUQ pain, often without jaundice unless near hilum

— Risk factors: diabetes, recent biliary procedure, travel for amebic

— CT shows liver lesion; treat with antibiotics + drainage (amebic — metronidazole usually without drainage)

— Can localize to RUQ

— No cholestatic LFT pattern; CT clarifies

— Hepatic congestion with mild LFT elevation, distended JVP, edema

— "Nutmeg liver" on imaging; treat underlying cardiac disease

— Hepatic vein thrombosis: abdominal pain, ascites, hepatomegaly, transaminitis

— Hypercoagulable workup; Doppler US, MR venography

— Rapid AST/ALT rise into thousands then quickly normalize after resuscitation

— Mild bilirubin rise; no biliary dilation

Step 3 management: Patient with fever, RUQ pain, leukocytosis, but normal LFTs and no ductal dilation → reconsider diagnosis; get CXR (right lower lobe pneumonia) and CT abdomen before committing to ERCP.

Board pearl: AST/ALT in the thousands with mild alk phos = hepatocellular injury (viral, ischemic, toxic) — not biliary obstruction.

Right-sided pneumonia / lower lobe pneumonia:

Acute viral hepatitis:

Alcoholic/drug-induced hepatitis:

Right pyelonephritis / renal colic with hydronephrosis:

Hepatic abscess (pyogenic or amebic):

Acute appendicitis with high-lying appendix or perforated peptic ulcer:

Right-sided heart failure / congestive hepatopathy:

Budd-Chiari syndrome:

Sepsis from non-biliary source with shock liver / ischemic hepatitis:

Secondary Prevention, Discharge Plan, and Long-Term Management

— Laparoscopic cholecystectomy during the same hospital admission after recovery from cholangitis (typically 24–72 h after clinical improvement) is the standard of care

— Reduces recurrent biliary events from ~20–25% to <5%

— In poor surgical candidates: leave permanent biliary stent or perform endoscopic sphincterotomy alone; accept some recurrence risk

— Discuss risk-benefit clearly; document shared decision-making

— Cholangiogram at end of ERCP should confirm clearance

— If incomplete clearance, plan repeat ERCP or surgical CBD exploration before cholecystectomy

— Large/intrahepatic stones may require advanced techniques (cholangioscopy with electrohydraulic or laser lithotripsy)

— Complete antibiotic course (4–7 days total after source control for uncomplicated; 10–14 d if Enterococcus bacteremia or incomplete drainage)

— Analgesia: acetaminophen ± short-course low-dose opioid; avoid chronic opioids

— PPI not routinely indicated unless other indication

— Resume home medications; reconcile anticoagulants

— Low-fat diet not strictly required after cholecystectomy but helps with adaptation

— Weight management; avoid rapid weight loss (precipitates new stones if gallbladder retained)

— Patients with retained gallbladder: discuss elective cholecystectomy timing

— PSC: annual MRCP + CA 19-9, colonoscopy q1–2 years (IBD-CRC risk)

— Choledochal cyst: surgical resection, then surveillance

— Sickle cell with pigment stones: prophylactic cholecystectomy considered

— Recurrent stones despite cholecystectomy: evaluate for retained stone, papillary stenosis, dysmotility; consider ursodeoxycholic acid in select cases

— Pneumococcal, influenza, COVID per age/risk

— Hepatitis A/B if not immune (especially in chronic liver disease)

Step 3 management: Discharging a 60-year-old s/p ERCP for cholangitis without cholecystectomy → arrange outpatient cholecystectomy within 2–6 weeks; if delaying, recurrence risk 15–30%. Coordinate handoff to surgery clinic before discharge.

Board pearl: Same-admission cholecystectomy after ERCP for choledocholithiasis is the right answer on Step 3 unless the patient is unfit for surgery.

Definitive prevention — interval cholecystectomy:

Stone clearance confirmation:

Discharge medications:

Lifestyle and dietary counseling:

Surveillance for high-risk patients:

Vaccinations and general prevention:

Follow-Up, Monitoring, and Counseling

— Vital signs q4h overnight (post-ERCP pancreatitis usually manifests within 6–12 h)

— Repeat LFTs at 12–24 h: should trend down

— Lipase at 6 and 24 h if abdominal pain develops or high PEP risk

— Clear liquids → advance diet as tolerated; early refeeding is safe

— Watch for delayed bleeding (melena, drop in Hgb) up to 2 weeks post-sphincterotomy

— Same-day or next-day discharge for uncomplicated laparoscopic cases

— Resume activity gradually; no heavy lifting >10 lb for 2 weeks

— Wound care; report fever, increasing pain, drainage, jaundice

— Surgery clinic 2 weeks post-cholecystectomy for wound check and pathology review (incidental gallbladder cancer in 1–2% of specimens)

— Primary care follow-up at 2–4 weeks: medication reconciliation, anticoagulant resumption timing, review of labs

— GI follow-up if biliary stent placed — typically remove or exchange within 8–12 weeks (plastic stents occlude); SEMS (self-expanding metal stents) for malignant indications have longer dwell time

— If PSC or other chronic biliary disease, hepatology follow-up

— Return precautions: fever, jaundice, persistent vomiting, melena, severe abdominal pain, confusion → ED immediately

— Importance of stent removal if one was placed (forgotten stents cause cholangitis)

— Discuss post-cholecystectomy syndrome: persistent dyspepsia/pain in 5–15%; evaluate for retained stone, sphincter of Oddi dysfunction, bile leak

— Bile leaks (cystic duct stump) present with pain, fever, fluid collection 3–7 days post-op → ERCP with stent

— LFTs at 2–4 weeks confirm normalization

— CBC if was anemic

— No long-term monitoring needed for uncomplicated case once stones cleared and gallbladder removed

Step 3 management: Patient returns 5 days after laparoscopic cholecystectomy with fever, RUQ pain, mild jaundice → suspect bile leak (cystic duct stump or duct of Luschka); order RUQ US/CT for biloma, HIDA or MRCP to localize, ERCP with biliary stent to decompress; percutaneous drain for collection.

Board pearl: Forgotten biliary stents cause recurrent cholangitis — document removal plan at the time of placement and at every transition of care.

Inpatient monitoring after ERCP:

Post-cholecystectomy recovery:

Outpatient follow-up cadence:

Counseling points:

Lab monitoring:

Ethical, Legal, and Patient Safety Considerations

— Specifically disclose post-ERCP pancreatitis (3–10%), bleeding (1–2%), perforation (<1%), infection, and risks of sedation

— In emergent cholangitis with altered mental status: obtain surrogate consent (next of kin per state hierarchy) or invoke emergency exception (implied consent) if life-threatening and no surrogate available

— Document capacity assessment when patient is septic but technically awake — sepsis often impairs decision-making capacity even without overt delirium

— Translator services (in-person or certified phone interpreter) for non-English speakers — never use family members for medical consent

— A patient with capacity may refuse ERCP even when life-saving; document discussion, alternatives offered (antibiotics alone with palliative intent), and surrogate involvement

— Reassess capacity if mental status changes; sepsis-related delirium is reversible — re-consent after recovery if temporizing measures used

— ED → floor: ensure antibiotic timing, drainage plan, NPO status communicated

— OR/Endoscopy → floor: confirm stent placement, anticoagulant resumption, pathology pending

— Hospital → home: forgotten biliary stent is a sentinel event; standardize stent-tracking registries

— Coordinate same-admission cholecystectomy — missed surgery = future ED bounce-back

— Sepsis 1-hour bundle: cultures, antibiotics, fluids, lactate, vasopressor escalation

— "Time-out" before ERCP: patient ID, indication, allergies, anticoagulation status, antibiotic prophylaxis given

— Closed-loop communication on critical labs (positive cultures, rising bilirubin)

— Suspected child abuse (rare in this disease but Step 3 may layer scenarios): unexplained pediatric pancreatitis with hepatobiliary trauma

— Adverse event reporting for serious procedural complications (perforation, death) per hospital risk management; root cause analysis

— Medical device tracking for stents (FDA UDI)

— Same-admission cholecystectomy reduces 30-day readmissions (a CMS quality metric)

— Antibiotic stewardship: narrow once cultures return; avoid carbapenem overuse

— Avoid unnecessary ERCP (low-probability stone) to reduce iatrogenic pancreatitis — use MRCP/EUS as gatekeeper

Step 3 management: Septic confused patient needs urgent ERCP; spouse available → obtain surrogate informed consent, document discussion, proceed. Do not delay life-saving drainage for legal formalities when surrogate consent is obtainable.

Board pearl: Forgotten biliary stent = preventable harm; build it into discharge checklists.

Informed consent for ERCP:

Refusal of care:

Transitions of care — high-risk handoff points:

Patient safety bundles:

Mandatory reporting and legal:

Health systems / value-based care:

High-Yield Associations and Rapid-Fire Clinical Facts

Board pearl: If the stem says "fever, jaundice, hypotension, confusion" — answer emergent ERCP within 12 hours, not antibiotics alone, not surgery first.

Charcot triad: RUQ pain + fever + jaundice = cholangitis (50–70% sensitivity)

Reynolds pentad: Charcot + hypotension + altered mental status = suppurative cholangitis, ICU

Courvoisier sign: palpable nontender gallbladder + painless jaundice = malignant obstruction (not stones)

5 F's for cholelithiasis: Female, Fat, Forty, Fertile, Fair (mnemonic, not gospel)

ALT >150 in suspected pancreatitis is 95% specific for gallstone etiology

AST:ALT >2:1 suggests alcoholic liver disease, not biliary obstruction

Cholestatic pattern: alk phos >>> AST/ALT, with elevated GGT confirming hepatobiliary source

CBD diameter: normal <6 mm; add 1 mm per decade after 60; post-cholecystectomy may dilate to 10 mm normally

Tokyo Guidelines (TG18): standard for cholangitis diagnosis and severity grading

ASGE high-probability criteria: CBD stone on imaging, cholangitis, bili >4 + dilated CBD → go to ERCP

Most common organism in cholangitis: E. coli (then Klebsiella, Enterococcus, Enterobacter)

Cephalosporins miss Enterococcus — use pip-tazo or add ampicillin if Enterococcus suspected

Rectal indomethacin 100 mg reduces post-ERCP pancreatitis

Same-admission cholecystectomy post-cholangitis prevents recurrence

Hypermucoviscous Klebsiella pneumoniae liver abscess → metastatic endophthalmitis (Asian patients)

Mirizzi syndrome: cystic duct stone compressing CHD → mimics CBD stone

Rigler triad (gallstone ileus): pneumobilia, SBO, ectopic stone

Recurrent pyogenic cholangitis (Oriental cholangiohepatitis): intrahepatic pigment stones, strictures; East Asia, Clonorchis sinensis

PSC + UC + young male → MRCP "beads on a string," cholangiocarcinoma risk

AIDS cholangiopathy: CD4 <100, CMV/Crypto, papillary stenosis

Choledochal cyst: RUQ mass + jaundice + pain in children → surgical excision

Cefepime in renal failure → neurotoxicity (encephalopathy, myoclonus, seizures)

PTBD is the rescue when ERCP fails or anatomy precludes (Roux-en-Y)

Plastic biliary stents occlude in 8–12 weeks → schedule exchange/removal

Vitamin K corrects cholestasis-related INR elevation; FFP/PCC for emergency reversal

Post-cholecystectomy bile leak: pain/fever 3–7 days post-op → ERCP + stent

Board Question Stem Patterns

— "65-year-old woman with RUQ pain, T 39.2, BP 96/58, confused, scleral icterus, bili 6, alk phos 480, WBC 18, US shows dilated CBD with stones."

— Best next step? → Resuscitate + IV broad-spectrum antibiotics + urgent ERCP within 12 hours

— Wrong answers: cholecystectomy first, MRCP, CT abdomen, observe

— "55-year-old with RUQ pain, mild jaundice, bili 2.8, alk phos 280, ALT 90, CBD 8 mm on US, no stone seen, afebrile."

— Best next test? → MRCP (intermediate probability — confirm before ERCP)

— "Lipase 1500, ALT 220, mild RUQ tenderness, no fever, bili 2.0, CBD 6 mm, no stone visualized."

— Management? → Supportive care, IV fluids, cholecystectomy before discharge; ERCP NOT indicated without cholangitis or persistent obstruction

— "Patient s/p successful ERCP with stone extraction yesterday for cholangitis, now afebrile, tolerating diet. Next step?"

— Answer: Laparoscopic cholecystectomy this admission

— "Cholangitis with prior biliary stent and recent hospitalization."

— Answer: Pip-tazo or cefepime + metronidazole (NOT ceftriaxone alone — misses Enterococcus and resistant gram-negatives)

— "6 hours after ERCP, severe epigastric pain radiating to back, lipase 1800."

— Diagnosis: Post-ERCP pancreatitis; treatment: IV fluids, NPO initially with early refeeding, analgesia, monitor

— "ERCP attempted twice, unable to cannulate CBD in patient with cholangitis and shock."

— Next step: Percutaneous transhepatic biliary drainage (PTBD) by IR

— "2nd-trimester pregnant woman with cholangitis."

— Imaging: MRCP without gadolinium if needed; treatment: ERCP with minimized fluoroscopy, ceftriaxone + metronidazole, OB co-management

— "70-year-old, painless jaundice, weight loss, palpable nontender gallbladder, bili 12, alk phos 600."

— Diagnosis: Pancreatic head adenocarcinoma; next step: CT pancreas protocol → ERCP with brushings + stent

— "Young man with UC, fatigue, cholestatic LFTs."

— Test: MRCP showing multifocal strictures; surveillance: CA 19-9, MRCP annually, colonoscopy q1–2 years

Step 3 management: When in doubt on cholangitis stems, the answer pattern is: fluids → antibiotics → ERCP (with urgency dictated by Tokyo grade) → interval cholecystectomy.

Board pearl: "Best next step" in unstable cholangitis = drainage, not more imaging.

Classic cholangitis stem:

Intermediate probability stem:

Gallstone pancreatitis stem:

Same-admission cholecystectomy stem:

Antibiotic choice stem:

Post-ERCP complication stem:

Failed ERCP stem:

Pregnancy stem:

Painless jaundice stem:

PSC stem:

One-Line Recap

Choledocholithiasis presenting as ascending cholangitis is a sepsis emergency treated by aggressive resuscitation, prompt broad-spectrum IV antibiotics targeting gram-negatives plus anaerobes and enterococci, urgent biliary drainage via ERCP (timing dictated by Tokyo severity grade — within 12 hours for Grade III, 24 hours for Grade II, 24–48 hours for Grade I), and same-admission laparoscopic cholecystectomy to prevent recurrence.

Board pearl: On every cholangitis question, the answer hierarchy is resuscitate → antibiotics → ERCP → cholecystectomy — choose the step the patient hasn't received yet.

Diagnose: Charcot triad (RUQ pain + fever + jaundice) or Reynolds pentad (add hypotension + confusion); cholestatic LFTs (alk phos, direct bili) + dilated CBD on US; use ASGE high-probability criteria to skip MRCP and go straight to ERCP

Resuscitate and treat: Sepsis bundle within 1 hour — cultures, IVF 30 mL/kg, lactate, vasopressors as needed; empiric pip-tazo (or ceftriaxone + metronidazole for community Grade I); add carbapenem ± vancomycin if healthcare-associated or Grade III

Drain the duct: ERCP with sphincterotomy + stone extraction is definitive; rectal indomethacin to prevent post-ERCP pancreatitis; PTBD when ERCP fails or anatomy precludes; never substitute antibiotics for drainage

Prevent recurrence: Same-admission laparoscopic cholecystectomy (or stent + endoscopic surveillance if unfit for surgery); track and remove biliary stents; coordinate transitions of care; document informed consent including PEP risk; pursue malignancy workup if Courvoisier sign or painless jaundice with weight loss