Ultrasonographic diagnosis of hepatobiliary ascariasis

Eight cases of hepatobiliary invasion of Ascaris lumbricoides into the hepatobiliary tract are presented. In the presence of nonspecific symptoms and biochemical test results, the diagnosis was made in seven patients by sonography. In the remaining patient, in whom the adult roundworm was not visible on sonography owing to the presence of aerobilia, the diagnosis was made at ERCP. Sonography revealed typical tubular, echogenic, filling defects along the long axis of a dilated common bile duct, sometimes exhibiting slow movements and containing a central sonolucent line. Repeated sonographic examinations accurately predicted treatment success.