Differential Diagnosis for a Distended Gallbladder

The presence of a distended gallbladder can be indicative of several conditions, each with varying degrees of urgency and potential impact on patient health. The differential diagnoses can be categorized as follows:

• Single Most Likely Diagnosis

  • Courvoisier's Law: This suggests that a distended gallbladder is more likely to be associated with a malignant obstruction of the bile duct, such as pancreatic cancer, rather than a stone. This is because stones typically cause chronic inflammation and scarring, leading to a fibrotic, non-distensible gallbladder.

• Other Likely Diagnoses

  • Choledocholithiasis: Stones in the common bile duct can cause obstruction, leading to gallbladder distension. This condition may present with jaundice and abdominal pain.
  • Cholecystitis: Inflammation of the gallbladder, often due to gallstones, can cause distension, especially if there is an obstruction of the cystic duct.
  • Biliary dyskinesia: A motility disorder of the gallbladder and biliary tree can lead to distension due to impaired emptying.

• Do Not Miss Diagnoses

  • Mirizzi's Syndrome: A rare condition where a gallstone becomes impacted in the cystic duct, causing obstruction of the common bile duct, which can lead to severe consequences if not promptly diagnosed and treated.
  • Ascending Cholangitis: An infection of the bile duct, which can be life-threatening if not treated promptly. It often presents with fever, jaundice, and abdominal pain (Charcot's triad).
  • Gallbladder rupture: Although less common, a distended gallbladder can rupture, leading to peritonitis, which is a surgical emergency.

• Rare Diagnoses

  • AIDS-related cholangiopathy: In patients with advanced AIDS, opportunistic infections can cause biliary tract disease, including a distended gallbladder.
  • Primary sclerosing cholangitis: A chronic liver disease characterized by inflammation and scarring of the bile ducts inside and outside the liver, which can lead to gallbladder distension among other symptoms.
  • Gallbladder hydrops: A condition where the gallbladder becomes distended with bile, often due to a benign obstruction of the cystic duct, and can be associated with systemic diseases like Kawasaki disease in children.