High prevalence of Anisakis simplex hypersensitivity and allergy in Sicily, Italy

Background: Anisakis simplex can elicit allergie reactions when ingested in raw or marinateci fìsh. The prevalence of A simplex hypersensitivity and allergy in Sicily {ltaly), an area where the consumption of raw or marinateci fìsh is very common, has not been investigateci thus far. Objective: To investigate the prevalence of A simplex sensitization and its clinica! relevance in a large group of unselected patients. Methods: Ali consecutive patients referred to the authors' allergy clinic during a 22 month-period were included in the study, evaluated for sensitization to A simplex and other allergens depending on their clinica! history, and investigateci for allergie symptoms after the ingestion of raw or marinateci fìs h. Results: Of 3.419 patients screened, 527 {15.4%) were sensitized to A simplex and 29 of these {5.5% of sensitized patients) had a history of A simplex allergy. Approximately 30% of patients had mono-sensitization to A simplex. Co-sensitization to house dust mites or molds yielded an odds ratio of 1.98 or 3.18, respectively, for allergy to A simplex. Conclusion: A high prevalence of A simplex sensitization in a large proportion of patients with monosensitization was found, confìrming that eating habits influence sensitization to this nematode. Allergie symptoms from A simplex ingestion in raw or marinateci fì sh were quite frequent, with symptoms ranging from ora! allergy syndrome to anaphylaxis. Patients sensitized to A simplex were more prone to have allergie symptoms when they had co-sensitization to house dust mites or molds, suggesting possible cross- reactive but clinically relevant allergens between these allergenic sources.