DIAGNÓSTICO DE LOS PACIENTES CON ALERGIA A GAMBA

Abstract

Background: Shellfish allergy is one of the main causes of food allergy in adults, and often causes anaphylaxis. It is estimated a global prevalence of 5.4%. Tropomyosin is the major allergen in shrimp and it is considered a cross-reactive panallergen, responsible of reactivity between crustaceans and mites. Exposure to mites can modify the divers allergenic profile to shrimp. Currently, shrimp allergy diagnosis include skin prick tests, specific IgE determinations and oral food challenge. _x000D_ _x000D_ Objectives: The main aim of this study was to evaluate the presence of cross-reactivity between shrimp and house dust mites in our population._x000D_ _x000D_ Methods: Patients with positive skin prick test to shrimp were recruited and classified into groups according to the clinics. Different allergenic extracts were prepared from shrimp and house dust mites, and its protein content was achieved. Skin prick tests and specific IgE to shrimp and Pen a 1 was measured. The allergenic profile was studied by means of SDS-PAGE and Western blot. Cross-reactivity was analysed by competition ELISA and Western blot. _x000D_ _x000D_ Results: 117 patients were enrolled, and 99 (84.6%) were classified as allergic to shrimp. The most reported symptoms were urticaria/angioedema (42.4%) and anaphylaxis (34.4%). 73.7% were also allergic to house dust mites. The newly prepared extracts had some proteins in common: tropomyosin, paramyosin, arginine kinase, triose phosphate isomerase and heat shock protein. Specific IgE to shrimp, to Pen a 1, and to the newly extracts did not showed statistical differences between allergic and non-allergic shrimp patients. Cross reactivity between shrimp and mites was demonstrated, with mites acting as a primary sensitizer. _x000D_ _x000D_ Conclusion: This is the first study performed in Barcelona that demonstrate the cross-reactivity between house dust mites and shrimp allergens. The primary sensitization was due to house dust mites. Cross reactivity could be explained because of the common proteins included in both extracts. Intraepidermal cutaneous test to these extracts, and specific IgE determinations to shrimp and to Pen a 1, fail to discern between shrimp allergic and non-allergic patients.

Date of Award	12 Mar 2019
Original language	Spanish
Supervisor	Antonio Luis Valero Santiago (Director)