Cholangitis with Normal Pancreatic Enzymes
A 30-year-old man presents with 8 hours of right upper quadrant pain after a year of recurrent milder attacks. Temperature is 37.9 °C and heart rate 110 beats/min. He is jaundiced with right hypochondrial tenderness. White cells are 16 × 10⁹/L, direct bilirubin 15 µmol/L, alkaline phosphatase 400 IU/L and amylase 115 IU/L. Ultrasound shows an 11 mm common bile duct with intrahepatic dilatation. Which diagnosis is most likely?
- A.Acute pancreatitis
- B.Acute cholecystitis
- C.Acute hepatitis
- D.Acute cholangitisCorrect
Explanation
All three elements of Charcot triad are present, namely right upper quadrant pain, fever with leukocytosis and jaundice, making acute ascending cholangitis the diagnosis. The biochemistry is cholestatic, with a direct hyperbilirubinaemia and an alkaline phosphatase several times the upper limit, which points to impaired bile flow rather than hepatocyte necrosis. Ultrasound confirms the obstruction, since a common bile duct of 11 mm is far above the normal 6 to 7 mm, and the associated intrahepatic duct dilatation shows the block lies distally so that bile backs up throughout the liver. His year of recurrent milder attacks is typical of intermittent stone impaction that has now progressed to infected obstructed bile. Acute pancreatitis is excluded because the amylase is within the reference range, and diagnosis requires enzyme elevation above three times normal or characteristic cross sectional imaging. Acute cholecystitis is excluded because the gallbladder is not the site of the problem; cystic duct obstruction does not cause jaundice or dilate the common duct, since bile can still drain from liver to duodenum. Hepatitis would show transaminase predominant derangement and would not dilate the biliary tree. Definitive treatment is endoscopic biliary drainage after antibiotics and resuscitation.
Why each option
- A.
- Pancreatitis is ruled out by a normal amylase of 115 IU/L; diagnosis requires enzymes above three times the upper limit or typical imaging findings.
- B.
- Cholecystitis follows cystic duct obstruction and characteristically spares the common bile duct, so it does not produce jaundice with intrahepatic dilatation.
- C.
- Hepatitis gives a hepatocellular enzyme pattern and never dilates the biliary tree; this patient has cholestatic labs with clear ductal dilatation.
- D.
- Correct. Pain, fever with leukocytosis and jaundice together with a dilated obstructed common bile duct define acute ascending cholangitis.
Reference: Sabiston Textbook of Surgery, 21st ed., 2022, Choledocholithiasis and Cholangitis
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