A duct stone raises pressure; infection turns pressure into sepsis.
Reference image for orientation, not a diagnostic studyA distal common-bile-duct stone with upstream dilation localizes obstruction and creates cholangitis and pancreatitis risk.Cerevisae / Wikimedia Commons (CC BY-SA 4.0). SourceCC BY-SA 4.0
Separate uncomplicated choledocholithiasis, gallstone pancreatitis, and acute cholangitis.
Use labs, ultrasound, MRCP or EUS, and ERCP according to pretest risk.
Apply Tokyo-style severity logic, prompt antibiotics, and urgent biliary drainage.
Biliary obstruction
Localize the obstruction before choosing the test
The figure links the level of obstruction to infection risk, imaging, and intervention.
Quick check
A 76-year-old man has fever, right upper quadrant pain, jaundice, confusion, and blood pressure 84/50 mm Hg. Alkaline phosphatase and direct bilirubin are elevated, and ultrasound shows a dilated common bile duct.
What is the most appropriate next step?
Reason it through
Which three findings make Charcot triad?Fever, right upper quadrant pain, and jaundice.
What completes Reynolds pentad?Hypotension and altered mental status.
What is the source-control target?The obstructed infected common bile duct.
Shock plus an infected duct is an ERCP emergency after immediate stabilization begins.
Map the obstruction before choosing the intervention
Ultrasound detects backup; MRCP or EUS confirms uncertain stones; ERCP clears high-risk ducts.
Ultrasound is the first imaging study for suspected biliary obstruction, but a distal common duct stone can be missed even when the duct is dilated.
For intermediate-risk choledocholithiasis, MRCP or EUS confirms the stone without exposing the patient to diagnostic ERCP complications.
A stone seen on imaging, ascending cholangitis, or the combination of total bilirubin greater than 4 mg/dL and a dilated common bile duct places a patient in an ASGE high-risk branch that can proceed directly to ERCP.
Place the test on the risk branch.
1Ultrasound
Look for gallstones, common duct dilation, and a visible duct stone.
2MRCP
Noninvasively map the duct when probability is intermediate and the patient is stable.
3EUS
Detect small distal stones or sludge and evaluate the ampulla or pancreas.
4ERCP
Drain infected bile, remove stones, perform sphincterotomy, or place a temporary stent.
5Intraoperative cholangiography
Evaluate and sometimes guide management of the common duct during cholecystectomy.
Follow a stone from migration to organ failure
Cholangitis develops when an obstructed duct can no longer contain bacteria and pressure.
A gallbladder stone migrates through the cystic duct into the common bile duct and may lodge distally near the ampulla.
Obstruction raises intraductal pressure, produces direct hyperbilirubinemia and alkaline phosphatase elevation, and often dilates upstream ducts.
Biliary stasis permits ascending enteric infection; rising pressure promotes bacteremia and systemic inflammation that can progress to shock and organ dysfunction.
Order the clinical progression.
A gallbladder stone enters the common duct.
Bile and sometimes pancreatic outflow are obstructed.
Direct bilirubin and alkaline phosphatase rise and ducts may dilate.
Enteric organisms multiply in stagnant bile.
Pressure and infection drive bacteremia, sepsis, and organ dysfunction.
Separate stone, pancreas, gallbladder, and infected duct
The same migrating stone can create adjacent syndromes with different ERCP timing.
Choledocholithiasis is a stone within the common bile duct and may cause pain, cholestatic labs, jaundice, duct dilation, or no symptoms.
Acute cholangitis adds infection and systemic inflammation to biliary obstruction; gallstone pancreatitis adds pancreatic injury from ampullary obstruction.
Acute cholecystitis is persistent cystic duct obstruction with gallbladder inflammation, not necessarily a common duct infection.
Compare the syndromes.
Common duct stone with obstruction but no systemic biliary infection.
Obstruction plus biliary infection and systemic inflammation.
Ampullary stone passage or impaction causes pancreatic inflammation and lipase elevation.
Persistent cystic duct obstruction inflames the gallbladder wall.
Name the injured compartment before deciding whether ERCP is urgent.
Use the classic signs, then outgrow them
Charcot triad is memorable but not sensitive enough to exclude disease.
Charcot triad is fever, right upper quadrant pain, and jaundice; Reynolds pentad adds hypotension and altered mental status and signals severe disease.
Tokyo-style diagnosis integrates systemic inflammation, cholestasis, and imaging evidence of biliary dilation or an obstructing cause rather than requiring every classic symptom.
Older adults and immunocompromised patients may lack fever or pain, so unexplained sepsis with cholestasis still deserves urgent biliary evaluation.
Select the complete Reynolds pentad.
Grade severity by organ impact, not by pain volume
Tokyo-style grades connect physiologic failure to drainage timing.
Grade III cholangitis is defined by organ dysfunction involving cardiovascular, neurologic, respiratory, renal, hepatic, or hematologic systems and requires urgent support and source control.
Grade II uses a cluster of risk features such as age at least 75 years, high fever, marked leukocytosis or leukopenia, bilirubin at least 5 mg/dL, or low albumin to identify patients needing early drainage even without organ failure.
Grade I lacks Grade II or III features and may respond to initial antibiotics and support, but failure to improve or persistent obstruction still prompts drainage.
Rank drainage urgency.
Antibiotics buy time; drainage controls the source
Treat infection immediately while preparing definitive decompression.
Start IV fluids and antibiotics promptly when cholangitis is suspected. Empiric therapy should cover likely enteric gram-negative organisms and, when clinically appropriate, anaerobes and enterococci, then narrow to cultures and local susceptibility data.
ASGE favors endoscopic over percutaneous drainage when feasible and suggests ERCP within 48 hours for cholangitis, with more urgent intervention when shock or organ dysfunction is present.
At ERCP, combine drainage with sphincterotomy and stone removal when the patient is stable enough; in a severely unstable patient, rapid decompression with a stent or nasobiliary drain may be safer than prolonged complete clearance.
Reveal the treatment decision for each branch.
Proceed to therapeutic ERCP or an accepted surgical duct-clearance strategy.
Avoid an extra diagnostic ERCP step when high-risk criteria are already met.
Confirm with MRCP, EUS, or intraoperative imaging.
Most of these patients do not need a diagnostic ERCP.
Continue antibiotics and arrange definitive source management; drain if response is inadequate.
Clinical response helps define the timing.
Provide early biliary drainage after initial treatment.
Tokyo severity features identify patients who benefit from early source control.
Resuscitate immediately and drain as soon as the patient can safely undergo the procedure.
Organ support and source control proceed together.
Antibiotics treat the bloodstream; drainage treats the reason bacteria reached it.
Stage 1 of 3: Overview
Overview
Choledocholithiasis and Acute Cholangitis
Cholangitis develops when an obstructed duct can no longer contain bacteria and pressure.
Step by step
Follow a stone from migration to organ failure
1Stone migrationA gallbladder stone enters the common duct.
2Distal impactionBile and sometimes pancreatic outflow are obstructed.
3Cholestatic backupDirect bilirubin and alkaline phosphatase rise and ducts may dilate.
4Ascending infectionEnteric organisms multiply in stagnant bile.
5Systemic escapePressure and infection drive bacteremia, sepsis, and organ dysfunction.
Clinical takeaway
Why it mattersBiliary stasis permits ascending enteric infection; rising pressure promotes bacteremia and systemic inflammation that can progress to shock and organ dysfunction.
RememberShock plus an infected duct is an ERCP emergency after immediate stabilization begins.
Obstruction level
Choose the branch that resolves the duct question
Determine the obstruction level and urgency before selecting imaging or intervention.
What is the most appropriate next step?
Key finding. A 76-year-old man has fever, right upper quadrant pain, jaundice, confusion, and blood pressure 84/50 mm Hg. Alkaline phosphatase and direct bilirubin are elevated, and ultrasound shows a dilated common bile duct.
Answer. Resuscitation, broad-spectrum IV antibiotics, and urgent biliary drainage by ERCP
Why. Reynolds pentad with obstructive findings is severe cholangitis requiring immediate sepsis care and source control.
Board rule. Shock plus an infected duct is an ERCP emergency after immediate stabilization begins.
Navigate the biliary cases
Five duct-stone cases test risk stratification, pancreatitis overlap, antibiotics, drainage timing, and how much ERCP to do now.
Cross out the wrong duct location and highlight the obstruction clue. Each case separates diagnosis from urgent decompression.
A 58-year-old woman has jaundice and right upper quadrant pain without fever. Ultrasound directly shows a stone in the common bile duct.
What is the most appropriate next step?
Reason it through
Was the stone inferred or seen?It was directly visualized in the common bile duct.
Which risk branch does that create?High risk for choledocholithiasis.
What is the goal of the next procedure?Clear or reliably drain the common duct.
A seen duct stone is a treatment target, not an imaging debate.
Was the stone inferred or seen?Which risk branch does that create?
Was the stone inferred or seen?It was directly visualized in the common bile duct.
Which risk branch does that create?High risk for choledocholithiasis.
What is the goal of the next procedure?Clear or reliably drain the common duct.
A 63-year-old man has biliary pain, mildly abnormal liver tests, and a 7 mm common bile duct on ultrasound, but no stone and no fever. Total bilirubin is 2.1 mg/dL.
Which diagnostic study should be obtained next?
Reason it through
Is a duct stone visible?No.
Does bilirubin exceed 4 mg/dL with dilation?No, it is 2.1 mg/dL.
Which branch fits?Intermediate risk, so MRCP or EUS should confirm the duct.
Intermediate risk earns MRCP or EUS, not diagnostic ERCP.
Is a duct stone visible?Does bilirubin exceed 4 mg/dL with dilation?
Is a duct stone visible?No.
Does bilirubin exceed 4 mg/dL with dilation?No, it is 2.1 mg/dL.
Which branch fits?Intermediate risk, so MRCP or EUS should confirm the duct.
A 45-year-old woman has acute pancreatitis with gallstones. She has no jaundice, cholangitis, or persistent cholestatic laboratory pattern, and ultrasound shows no common duct dilation.
Which ERCP principle is correct?
Reason it through
What complication is present?Acute gallstone pancreatitis.
What urgent ERCP trigger is absent?There is no cholangitis or persistent common duct obstruction.
What should happen after recovery?Definitive gallbladder management should prevent recurrence.
Pancreatitis alone does not make urgent ERCP automatic.
What complication is present?What urgent ERCP trigger is absent?
What complication is present?Acute gallstone pancreatitis.
What urgent ERCP trigger is absent?There is no cholangitis or persistent common duct obstruction.
What should happen after recovery?Definitive gallbladder management should prevent recurrence.
A 79-year-old woman has fever, jaundice, leukocytosis, bilirubin 6.2 mg/dL, and a dilated common bile duct. Blood pressure and mental status are normal, and there is no renal or respiratory failure.
Which Tokyo-style severity and drainage plan best fit?
Reason it through
Is organ dysfunction present?No, so this is not Grade III.
Which Grade II features are present?Age at least 75 years, bilirubin at least 5 mg/dL, and marked inflammation.
What does Grade II change?It supports early biliary drainage after initial antibiotics and stabilization.
Moderate cholangitis is early-drainage disease even before organs fail.
Is organ dysfunction present?Which Grade II features are present?
Is organ dysfunction present?No, so this is not Grade III.
Which Grade II features are present?Age at least 75 years, bilirubin at least 5 mg/dL, and marked inflammation.
What does Grade II change?It supports early biliary drainage after initial antibiotics and stabilization.
A patient with severe cholangitis is improving after fluids, vasopressors, and antibiotics but remains too unstable for a prolonged ERCP. A large impacted common duct stone is present.
What is the best endoscopic principle?
Reason it through
What is the immediate treatment goal?Lower duct pressure and drain infected bile.
Why not insist on complete extraction now?Procedure length and complexity can be unsafe during severe physiologic instability.
What happens after stabilization?Return for definitive stone clearance and plan gallbladder management.
In the crashing patient, drainage now beats perfect clearance later in the same procedure.
What is the immediate treatment goal?Why not insist on complete extraction now?
What is the immediate treatment goal?Lower duct pressure and drain infected bile.
Why not insist on complete extraction now?Procedure length and complexity can be unsafe during severe physiologic instability.
What happens after stabilization?Return for definitive stone clearance and plan gallbladder management.
Rapid review
Three questions to check
What is the most appropriate next step?
Resuscitation, broad-spectrum IV antibiotics, and urgent biliary drainage by ERCP. Reynolds pentad with obstructive findings is severe cholangitis requiring immediate sepsis care and source control.
Was the stone inferred or seen?
It was directly visualized in the common bile duct.
Resident physician and founding medical reviewer at Bone Wizardry, focused on clinical accuracy, clear diagnostic reasoning, and practical board-oriented teaching across the curriculum.
