Plant-derived foods cause most food allergies in Italian adults. The pollen-food allergy syndrome is the most frequent type of food allergy followed by allergy to LTP whose frequency increases southbound. The pattern of allergy to certain foods is clearly influenced by specific geographic features such as pollen exposure and dietary habits.

Background: Data about food-induced anaphylaxis in Italy are missing. Objective: It was the aim of this study to detect the main foods/food allergens causing anaphylaxis in Italy. Methods: The frequency of anaphylaxis and the relative importance of many offending foods were assessed in 1,110 adult patients with food allergy diagnosed by common criteria at 19 allergy centres scattered throughout Italy from 1 January to 31 December 2007. Results: Fifty-eight of 1,110 (5%) food-allergic patients experienced at least 1 episode of anaphylaxis. On average, they were older than other food-allergic patients (34 vs. 31 years; p < 0.05). The majority of anaphylactic episodes occurred in patients sensitized to lipid transfer protein (LTP; n = 19), followed by shrimp (n = 10), tree nuts (n = 9), legumes other than peanut (n = 4), and seeds (n = 2); peanut, spinach, celery, buckwheat, wheat, avocado, tomato, fish, meat, and Anisakis caused an anaphylactic reaction in single patients. Among LTP-hypersensitive patients, peach caused 13/19 anaphylactic episodes. Shrimp-allergic patients were significantly older than other patients with food-induced anaphylaxis (p < 0.05), whereas patients allergic to LTP experienced their anaphylactic episodes at a younger age (p < 0.001). The frequency of anaphylaxis among patients sensitized to LTP, shrimp or tree nuts did not differ between northern and central/southern Italy. Conclusion: LTP is the most important allergen causing food-induced anaphylaxis in Italy, peach being the most frequently offending food. Peanut-induced anaphylaxis seems very uncommon. Geographic and environmental differences both between Italy and other countries and within Italy seem to play a relevant role in the pattern of sensitization to foods.

Inhaled furosemide has been shown to prevent bronchoconstriction induced by inhalation of ultrasonic nebulization of distilled water (UNDW) in bronchial asthma. To evaluate whether inhaled furosemide also prevents the increase in serum neutrophil chemotactic activity (NCA) observed during UNDW bronchoconstriction, we measured NCA during UNDW challenge without (control) and immediately after inhalation of furosemide (40 mg) or placebo (saline) in 10 asthmatics responsive to UNDW, in a randomized, double-blind study. NCA was assessed by measuring the maximal distance reached by neutrophils in a filter when challenged with the subject serum in a Boyden chamber ("leading front"). UNDW inhalation produced a significant increase in NCA in each subject. Gel filtration chromatography on S400 column indicated that the NCA released were 600 to 700 kD. Saline had no effect on bronchoconstriction nor on NCA increase induced by UNDW in nine patients. Furosemide did not change baseline FEV1, but it prevented bronchoconstriction and NCA increase in nine patients. In the whole group the maximal decrease in FEV1 after UNDW was -31.1%, SEM 4.7 after saline and -7.5%, SEM 5.2 after furosemide, p less than 0.001, the maximal increase in NCA after UNDW was +52.9%, SEM 9.2 after saline and +3.8%, SEM 3.1 after furosemide, p = 0.001. These results indicate that inhaled furosemide prevents both the bronchoconstriction and the NCA increase induced by UNDW inhalation in most asthmatic patients. This finding adds support to the suggestion that furosemide acts on mast cells.

Previous studies on the effect of seasonal exposure to the sensitizing antigen on T-cell cytokine pattern from atopic subjects evaluated T-cell cytokine production by titration in the serum or culture supernatants. The purpose of this study was to determine the seasonal variations of T-cell cytokine pattern from atopic subjects at the single-cell level. We examined the interleukin-4 (IL-4) and interferon-gamma expression in peripheral blood CD4 + and CD8 + T cells from 11 subjects with grass-pollen-sensitive allergy before and during the 1999 grass pollen season using a flow cytometric method of intracellular cytokine detection. Eight healthy volunteers served as the control group. Flow cytometric analysis of peripheral blood lymphocytes showed no seasonal variations of IL-4- and interferon-gamma-producing T cells in atopic subjects. However, there was a decreased percentage of IL-4-producing cells among peripheral blood CD4+ and CD8+ T cells from the atopic subjects both during and outside the pollen season in comparison to the controLs. We did not find seasonal variations of T-cell cytokine pattern in peripheral blood from atopic subjects. However, we observed a decreased percentage of IL-4-producing T cells in peripheral blood from these subjects in comparison to healthy controls. These data add to the view of a continuous migration of T helper 2 (TH2) cells from the blood to the tissues of primary allergen exposure.

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