Human anisakiasis in Italy: a report of eleven new cases

The authors report on eleven new human cases of anisakiasis occurring in Italy, and emphasize the importance of the infection in clinical medicine, histopathology and public health. For ten of these cases, the diagnosis was based on histological findings: an eosinophilic granuloma associated with a larva of Anisakis sp. For one of them, the larva was removed from the stomach by endoscopy. Nine of the subjects were from Apulia and two from Molise (regions of southern and central Italy, respectively). Ten of them were surgically treated, and in one case the endoscopical extraction of the parasite resolved the situation. In two cases, the gastric wall was affected, in three the intestinal wall, in a further three the omentum, in one the spleen, and in the final two the mesentery and the epiploic appendix. In all the cases, the parasite was discovered unexpectedly during surgical treatment of the patients for supposed illnesses, which had originally been misdiagnosed. In three cases, the patients were also affected by cancer. Human anisakiasis must be taken into account in the differential diagnosis of acute, abdominal synddromes in subjects who have ingested raw fish or squid a few hours to a few days before the onset of symptoms. Histopathologists should consider the possibility of this parasitic infection when confronted with an eosinophilic granuloma of the digestive tract, mesentery or peritoneum. The incidence of anisakiasis in Italy is probably higher than reported, as some cases might not be diagnosed and others might heal spontaneously.