An alien in the gallbladder. A rare case of biliary ascariasis in an Italian emergency department

Ascariasis is a common infection in many developing countries. The prevalence of ascariasis is related to poverty, poor hygienic and sanitary conditions. The adult form of Ascaris lumbricoides usually resides in the human intestinal lumen (more frequently in the jejunum and middle ileum) and does not cause symptoms. However, it can occasionally cause severe complications such as intestinal obstruction or perforation peritonitis. Its migration into the biliary tract is not uncommon but gallbladder involvement is very rare. Abdominal ultrasonography is essential to detect the presence of this parasite. In this article, we describe the radiologic findings, clinical manifestations and successful medical treatment of a patient with gallbladder ascariasis diagnosed in an emergency setting.