Ascariasis of the alimentary tract, liver, pancreas and biliary system: its diagnosis by ultrasonography

BACKGROUND/AIMS: The purpose of this study was to describe the echographic features of Ascaris lumbricoides invasion of the alimentary tract, biliary system, liver and pancreas. METHODOLOGY: We studied 38 patients with roundworm heavy infection whose diagnosis were primarily supported by ultrasonographic examination. RESULTS: Thirty-seven patients were admitted with the following clinical complications: bowel obstruction, intra and extrahepatic dilatation, acute cholecystitis, intrahepatic abscess, acute appendicitis, subphrenic collection and acute pancreatitis. Ultrasound scanning was able to recognize in 30 cases the echogenic, nonshadowing images of the worms as single or multiple strips; in 8 cases, coiled structures and amorphous material were detected. The "inner tube" sign was considered as the most specific one. In two cases the roundworms were displayed within the stomach, a curious finding, up to now never reported in medical literature. CONCLUSIONS: Real-time sonography represents an efficient, reliable and non-invasive diagnostic approach for hepatobiliary, enteric and pancreatic ascariasis.