Gastroenterology · Biliary Tract Disease

Choledocholithiasis

USMLE2PANCE
7

Bets

The facts most likely to be tested

1

Choledocholithiasis presents with biliary colic and obstructive jaundice, characterized by elevated direct bilirubin and alkaline phosphatase.

Confidence:
2

The initial diagnostic test of choice for suspected choledocholithiasis is transabdominal ultrasound, which typically shows common bile duct (CBD) dilation.

Confidence:
3

Endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard for both the diagnosis and therapeutic extraction of common bile duct stones.

Confidence:
4

Magnetic resonance cholangiopancreatography (MRCP) is the preferred non-invasive diagnostic modality for patients with an intermediate probability of choledocholithiasis.

Confidence:
5

Charcot's triad of fever, right upper quadrant (RUQ) pain, and jaundice indicates the presence of acute ascending cholangitis.

Confidence:
6

Reynolds' pentad, consisting of Charcot's triad plus hypotension and altered mental status, signifies septic shock and requires emergent biliary decompression.

Confidence:
7

Patients with choledocholithiasis should undergo cholecystectomy after stone extraction to prevent recurrent biliary events.

Confidence:

Vignette unlocked

A 62-year-old female presents to the emergency department with a 2-day history of right upper quadrant pain and dark-colored urine. Physical examination reveals scleral icterus and tenderness in the RUQ without rebound or guarding. Laboratory studies demonstrate a total bilirubin of 4.8 mg/dL, direct bilirubin of 3.5 mg/dL, and an alkaline phosphatase of 320 U/L. An abdominal ultrasound reveals a dilated common bile duct of 12 mm with a shadowing stone.

What is the most appropriate next step in management?

+Reveal answer

Endoscopic retrograde cholangiopancreatography (ERCP)

The patient has confirmed choledocholithiasis with obstructive jaundice; ERCP is the definitive diagnostic and therapeutic procedure to remove the obstructing stone.

Mo

Depth

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High yield triage

Etiology / Epidemiology

Presence of gallstones in the common bile duct. Most common in patients with cholelithiasis.

Clinical Manifestations

Prolonged RUQ pain, jaundice, and Charcot's triad (fever, jaundice, RUQ pain).

Diagnosis

ERCP is the gold standard for both diagnosis and therapeutic intervention.

Treatment

ERCP with stone extraction is first-line; cholecystectomy follows to prevent recurrence.

Prognosis

Risk of ascending cholangitis and gallstone pancreatitis; mortality increases with Reynolds' pentad.

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Epidemiology & Etiology

Occurs in 10-15% of patients with symptomatic cholelithiasis. Primary stones form within the duct, while secondary stones migrate from the gallbladder. Risk factors include advanced age, female sex, and obesity.

Pertinent Anatomy

The common bile duct (CBD) is the distal portion of the biliary tree. Obstruction at the ampulla of Vater prevents bile flow into the duodenum, causing proximal ductal dilation.

Pathophysiology

Stones cause mechanical obstruction of the CBD, leading to cholestasis and elevated conjugated bilirubin. Stasis promotes bacterial overgrowth, potentially progressing to ascending cholangitis. Increased intraductal pressure can also cause reflux into the pancreatic duct, triggering pancreatitis.

Clinical Manifestations

Patients present with persistent RUQ pain and jaundice. Charcot's triad (fever, jaundice, RUQ pain) indicates infection. Reynolds' pentad (Charcot's triad + hypotension + confusion) signals septic shock and is a surgical emergency.

Diagnosis

Initial screening is via transabdominal ultrasound, which may show CBD dilation >6 mm. ERCP is the gold standard for definitive diagnosis and extraction. MRCP is the preferred non-invasive diagnostic modality for high-suspicion cases.

Treatment

ERCP with sphincterotomy and stone extraction is the first-line treatment. Cholecystectomy is mandatory post-ERCP to prevent recurrent stone formation. If ERCP fails, surgical common bile duct exploration is required.

Prognosis

Untreated obstruction leads to ascending cholangitis, liver abscess, or biliary cirrhosis. Patients require monitoring for pancreatitis and recurrent biliary colic.

Differential Diagnosis

Cholecystitis: positive Murphy's sign, no jaundice

Ascending Cholangitis: presence of systemic sepsis/fever

Gallstone Pancreatitis: elevated lipase/amylase

Biliary Colic: pain resolves within 6 hours

Malignancy: painless jaundice, Courvoisier's sign