Anisakiasis: The Importance of Prevention and the Role of Diet Therapy in Allergic Patients.

INTRODUCTION: Anisakiasis is a zoonosis of parasitic origin whose diffusion seems to be continuously increasing. OBJECTIVE: The aim of this study was to evaluate the benefits of a fish-free diet in patients allergic to Anisakis simplex as well as underlining the importance of awareness and prevention. Furthermore, we aimed to investigate the critical issues related to the spread of anisakiasis in relation to eating habits. METHODS: Patients were assessed by means of skin prick tests (SPTs) and targeted laboratory testing, with an 18-month-long fish-free diet being recommended in cases of severe sensitization. The degree of awareness about anisakiasis was evaluated from interviews. Patients were subjected to follow-up visits after 18 months. RESULTS: A total of 70 cases of sensitization to A. simplex were evaluated. The Interview answers highlighted a general state of misinformation among patients and healthy subjects along with a remarkable underestimation of anisakiasis-related risks. An overall lack of care regarding eating habits and diet plans also emerged. In 21 patients affected by severe sensitization, clinical and laboratory evaluations were repeated after 18 months of the subjects being on a fish-free diet. There was a remarkable improvement in serum IgE levels and clinical symptoms. CONCLUSION: Data analysis proved the need to implement new and more effective awareness-raising and prevention campaigns in order to reduce the incidence of anisakiasis. It is crucial to establish an adequate diet therapy for sensitized patients. Evaluation of cytokine patterns suggests how a polyphenol-rich regime can activate regulatory T cell function and possibly reduce the allergic and inflammatory components of the disease.

Anisakiasis, an underestimated infection: effect on intestinal permeability of Anisakis simplex-sensitized patients.

Anisakis simplex is a parasite that, if present in uncooked and contaminated saltwater fish, can invade the human gut. Two different clinical situations are recognized: the first, known as a gastrointestinal disease, varying from an asymptomatic episode to vomiting and diarrhea, and the second, classified as an adverse reaction to food, characterized by a wide spectrum of allergic reactions like rhinitis, conjunctivitis, or even anaphylaxis causing hypotension and/or shock. The intestinal epithelium, the major defense system against external molecules, represents an open gate for toxins and allergens if its protective function is compromised. Previous data have demonstrated a strict relationship between an altered intestinal permeability (I.P.) and worsening of the clinical manifestations in patients with adverse reactions to the food. In this article we evaluated the sensitization to A. simplex among patients who referred clinical symptoms of allergy. All subjects underwent commonly used alimentary skin prick test for food allergens, to which Ani s1, an A. simplex allergen, was added. In addition, in A. simplex-sensitized subjects, I.P. was determined upon their enrolment to the study (time 0) and after 6 months of consuming a raw fish-free diet (time 6). Five hundred and forty subjects were screened, and 170 had a positive skin prick test, 87 (51.2%) of whom were positive to Ani s1. Increased I.P. was evidenced in A. simplex-sensitized subjects with worse clinical symptoms, which receded after 6 months' elimination of raw seafood. With our data we demonstrated that the alimentary habit to eat raw fish represents a high risk for the integrity of the intestinal mucosa, and we suggest that this pathological situation may constitute an ideal, under-estimated, open gate for molecules that predispose to other, more important pathologies.

Specific and total IgE in patients with recurrent, acute urticaria caused by Anisakis simplex.

Titres of parasite-specific IgE were investigated in 19 patients thought to have recurrent, acute urticaria caused by sensitization to Anisakis simplex (Dujardin, 1845), before and after they were placed on a fish-free diet. Patients with other allergic disease and those being treated with corticosteroids or antihistaminics were excluded. Skin-prick tests were carried out with A. simplex extract, and blue- and white-fish extracts. The CAP system (Pharmacia), a commercial test kit developed for the assay of food-specific IgE, was used to monitor serum concentrations of total IgE and antigen-specific IgE against Anisakis, Ascaris, Echinococcus, Toxocara, tuna, salmon, shrimp, mussel and cod. Before going on a fish-free diet, the 19 patients had CAP scores against A. simplex of 5 (three cases), 3 (seven) or 2 (nine). After a mean of 120 days on the diet, the scores against A. simplex were unchanged in 15 of the cases, reduced in three [from 5 to 4 (one case) or from 2 to 0 (two cases)] and increased in one (from 2 to 3). Most (16) of the patients no longer had any urticaria and the others reported significant reductions in the intensity and frequency of their symptoms.