Actinomycosis of the intrahepatic bile duct concomitant with intrahepatic duct stones

Actinomycosis is a chronic, suppurative, granulomatous disease caused by Actinomyces species, a filamentous, Gram-positive anaerobic bacterium and a normal inhabitant of the oral cavity and gastrointestinal tract characterized by sulfur granule formation. Primary bile duct actinomycosis is very rare in Korea and the pathogenesis of this infection is poorly understood. We report a case of actinomycosis of the intrahepatic bile duct, concomitant with common bile duct and intrahepatic duct stones presenting as intermittent right upper quadrant abdominal pain without fever as the chief complaint in a 50-year-old woman. The radiologic findings revealed multiple intrahepatic duct and common bile duct stones. On performing a left lobectomy of the liver and endoscopic retrograde cholangiopancreatography, marked dilatation of the intrahepatic bile duct and many brown pigment stones in the intrahepatic duct and common bile duct were observed. Primary bile duct actinomycosis was confirmed by identifying sulfur granules with neutrophilic infiltration in the intrahepatic duct. (Korean J Med 77:343-348, 2009)