Bile duct hamartoma

Bile duct hamartoma or biliary hamartoma, are benign lesions of the intrahepatic bile duct. They are classically associated with polycystic liver disease, as may be seen in the context of polycystic kidney disease, and represent a malformation of the liver plate.

Signs and symptoms
Most patients are asymptomatic. When patients do present with symptoms the most common symptom is abdominal pain. Other symptoms include fever, weight loss, and jaundice.

Causes
Biliary duct hamartomas are defects resulting from the failure of embryonic bile duct involution that affect the small interlobular bile ducts. Patients with polycystic kidney disease and polycystic liver are far more likely to have them.

Diagnosis
Laboratory findings include high transaminase levels, raised gamma-glutamyl transferase or alkaline phosphatase levels, increased C-reactive protein, hypoalbuminemia, and hematologic abnormalities like thrombocytopenia, leukopenia, leukocytosis, and anemia.

At CT scans, bile duct hamartomas appear as small, well-defined hypo- or isoattenuating masses with little or no enhancement after contrast administration. At MRI, they appear hypointense on T1-weighted images, iso- or slightly hyperintense on T2-weighted images, and hypointense after administration of gadolinium based contrast-agent.

Eponym
The eponymous terms (von Meyenburg complex, Meyenburg complex) are named for Hanns von Meyenburg.