[Anisakiasis: an infestation to be known by surgeons]

Anisakis infestation is related to the consumption of raw or undercooked fish. It can cause allergic reactions, or abdominal pain when the gastrointestinal tube is involved. Its incidence is rising in Europe.

To analyze a group of patients complaining of right iliac fossa pain with ileitis or colitis and establish its relationship with Anisakis spp. infection.

During a 3-months period, 28 patients with abdominal pain were referred to the hospital with a diagnosis of ileitis or colitis by imaging, endoscopy or surgery. Specific serology for Anisakis was performed in all of them.

At imaging study, 14 patients had ileitis or colitis, three intestinal obstruction and one acute appendicitis. Fourteen patients were operated on and 7 of them underwent resection; histopathologic diagnosis were eosinophilic ileitis (2 cases) or colitis (3 cases), non specific ileitis (1 case) and Crohn's disease (1 case). Another patient had an endoscopic biopsy that concluded eosinophilic colitis. Anisakis serology was positive in 25 (89%), negative in two and unknown in one. All patients were discharged uneventfully.

Digestive anisakiasis may present as acute abdomen. Surgeons should know and consider this diagnosis in patients with ileitis or colitis, moreover if an antecedent of raw or undercooked fish ingestion is present. A conservative approach is best performed but the clinical picture can require an emergent laparotomy.