Biliary ascariasis presenting in the United States.

Infestation of the bile ducts by the adult Ascaris lumbricoides roundworm is a common condition in many parts of the world. The most frequent clinical presentation is as upper abdominal colicky pain with a normal or only slightly raised serum bilirubin. In most cases these worms can be visualized by intravenous cholangiography because of the absence of obstructive jaundice and can therefore be specifically treated by nonsurgical methods. The radiographic appearance is diagnostic. This is the first report of such a case presenting in North America or the United Kingdom, where the importance of biliary ascariasis in endemic areas is not fully appreciated.