Anisakis infestation: a case of acute abdomen mimicking Crohn's disease and eosinophilic gastroenteritis.

Anisakiasis is a rare parasitic disease transmitted to humans by the ingestion of raw fish, which can initially present with acute abdomen. We report the case of a man, a habitual consumer of raw fish, who underwent surgery for acute abdomen, initially attributed to Crohn's disease and then later interpreted as eosinophilic enteritis. Only the subsequent careful histological examination of the surgical specimen, revealing full thickness eosinophilic infiltrate, generally typical of infestation, led to the detection of Anisakis simplex larva. In cases of acute abdomen, in the presence of a positive history of raw fish ingestion, it is therefore reasonable to consider the possibility of anisakiasis.