Asero R.,Ambulatorio di Allergologia |
Arena A.,Ambulatorio Allergologia |
Cervone M.,Servizio di Allergologia |
Crivellaro M.,University of Padua |
And 11 more authors.
European Annals of Allergy and Clinical Immunology | Year: 2013
Background: The prevalence of IgE reactivity against genuine walnut and hazelnut allergens is poorly defined. Objective: The IgE response to walnut and hazelnut was investigated in Italian patients with primary allergy to these nuts. Methods: Sera from 36 patients allergic to hazelnut and/or walnut, not reactive to PR-10, profilin, and LTP, underwent immunoblot analysis with extracts of both nuts. Results: Most patients had a history of systemic symptoms following the ingestion of the offending food(s). Twelve patients were sensitized to both walnut and hazelnut, and 13 were sensitized to other nuts and seeds (cashew, peanut, sesame, pine nut, almond, Brazil nut, and pistachio). On walnut immunoblot, the 7 sera which scored positive showed much variability in their IgE profile. Two reacted uniquely at 10 kDa, and the others at 35, 40, 45, 50, 67, and > 67 kDa. The profiles obtained under reducing and non-reducing conditions showed several differences. The 7 sera positive on hazelnut immunoblot under reducing conditions recognized sera at 10 kDa and at <10 kDa (n=1), 20 kDa (n=4), at about 22, 24, 30, 40, 43, 58, 60, and 90 kDa, and higher m.w. in other cases. Under non-reducing conditions IgE reactivity at 20, 28, 35, 40, 45, 60, 90, and 100 kDa, was detected. Only two sera scored positive under both conditions and showed an IgE profile that partly changed from one assay to another. Conclusion: The current list of walnut and hazelnut allergens is far from being complete. Both reducing and non-reducing conditions are needed to detect IgE reactivity in individual patients.
Asero R.,Ambulatorio di Allergologia |
Mistrello G.,Lofarma SpA |
Amato S.,Lofarma SpA |
Ariano R.,Ospedale di Bordighera |
And 12 more authors.
International Archives of Allergy and Immunology | Year: 2012
Background: Shrimp is a frequent cause of food allergy worldwide. Besides tropomyosin, several allergens have been described recently. Objective: We investigated which allergens are involved in Italian shrimp-allergic adults. Methods: Sera from 116 shrimp-allergic patients selected in 14 Italian allergy centers were studied. Skin prick tests with house dust mite (HDM) as well as measurements of IgE to Pen a 1 (shrimp tropomyosin) and whole shrimp extract were performed. All sera underwent shrimp immunoblot analysis, and inhibition experiments using HDM extract as inhibitor were carried out on some Pen a 1-negative sera. Results: Immunoblots showed much variability. IgE reactivity at about 30 kDa (tropomyosin) was found in <50% of cases, and reactivity at about 67 kDa and >90 kDa was frequent. Further reactivities at 14-18, 25, 43-50, about 60 and about 80 kDa were detected. Most subjects had a history of shrimp-induced systemic symptoms irrespective of the relevant allergen protein. IgE to Pen a 1 were detected in sera from 46 (41%) patients. Skin reactivity to HDM was found in 43/61 (70%) Pen 1-negative subjects and inhibition studies showed that pre-adsorption of sera with HDM extract induced a marked weakening of the signal at >67 kDa. Conclusions: Several allergens other than tropomyosin are involved in shrimp allergy in adult Italian patients. Some hitherto not described high molecular weight allergens seem particularly relevant in this population and their cross-reactivity with HDM allergens makes them novel potential panallergens of invertebrates. Copyright © 2011 S. Karger AG, Basel.
Macchia D.,UO Allergologia Immunologia Clinica |
Capretti S.,UO Allergologia Immunologia Clinica |
Cecchi L.,Allergologia |
Colombo G.,Unita di Allergologia |
And 15 more authors.
Italian Journal of Allergy and Clinical Immunology | Year: 2011
Food allergy (FA) is an important problem due to its increasing prevalence in general population and to its broad range of clinical manifestations (from mild symptoms to anaphylactic shock, sometimes fatal). The identification of the food responsible for symptoms, using all the available standardized diagnostic methods, must be the main goal. The diagnosis of food allergy should be based on a correct procedure, that starts from a thorough clinical history and proceeds through the performance of in vivo and in vitro diagnostic methods, with a progressive level of complexity. The recent development of molecular biology techniques, that implies the use of molecular allergens, has improved the knowledge of food allergens and designs a component resolved sensitization profile (CRD: Component Resolved Diagnosis) for each patient, with important clinical and therapeutic consequences. However, the increasing use of in vitro routine tests based on molecular allergens runs the risk of possible, potentially serious mistakes. The Specialist in Allergology and Clinical Immunology should manage this complicated matter, after an adequate training. Therefore, a shared and standardized diagnostic pathway is mandatory. The aim of this position statement is to suggest the basic points in the adult food allergy diagnosis.