Context: Ascaris lumbricoides is the second most common intestinal parasite world-wide and, although the infection can be asymptomatic, in some cases it can present with complications, such as acute pancreatitis.
Case report: We describe the case of a 37-year-old man, with a history of travelling in Eastern countries who presented with Ascaris lumbricoides-induced acute pancreatitis mimicking a small pancreatic cancer, diagnosed during an upper EUS. The endoscopy revealeda roundworm floating in the duodenum; its endoultrasonographic appearance showed a diffuse inhomogeneous pattern, with hypoechoic echotexture, such as in acute pancreatitis. Microbiological examination of the worm revealed a 20 cm long Ascaris lumbricoides.
Conclusion: In non endemic countries, acute pancreatitis induced by Ascaris lumbricoides is an unusual diagnosis, and should be suspected especially in patients with history of traveling in endemic areas.