Caroli's disease misdiagnosed as intraductal papillary neoplasm of the bile duct.

Caroli's disease is a rare autosomal-recessive disorder caused by malformation of the ductal plate during embryonic development. Although it is present at birth, Caroli's disease is typically not diagnosed until between the second and fourth decades of life, as it was in the present patient. Here we report a rare case of Caroli's disease limited to one liver segment, which was initially misdiagnosed as an intraductal papillary neoplasm of the bile duct. The asymptomatic patient was treated with liver segmentectomy.