IgE-Mediated Sensitization to Galactose-α-1,3- Galactose (α-Gal) in Urticaria and Anaphylaxis in Spain: Geographical Variations and Risk Factors
Mateo-Borrega MB1, Garcia B2, Larramendi CH3, Azofra J4, González-Mancebo E5, Alvarado MI6, Alonso Díaz de Durana MD7, Núñez-Orjales R8, Diéguez MC9, Guilarte M10, Soriano-Galarraga AM11, Sosa G12, Ferrer A13, García-Moral A14, Beristain AM15, Bartra J16
1GAI Guadalajara, Department of Allergy, Hospital Universitario de Guadalajara, Guadalajara, Spain
2Department of Allergy, Complejo Hospitalario de Navarra, Pamplona, Spain
3Allergy Section, Hospital Marina Baixa, Villajoyosa, Spain
4Department of Allergy, Hospital Universitario Central de Asturias, Oviedo, Spain
5Department of Allergy, Hospital Universitario de Fuenlabrada, Madrid, Spain
6Department of Allergy, Hospital Virgen del Puerto, Plasencia, Spain
7Department of Allergy, Hospital Universitario Fundación de Alcorcón, Madrid, Spain
8Department of Allergy, Hospital Universitario Lucus Augusti, Lugo, Spain
9Department of Allergy, Research Institute Hospital 12 de Octubre (i+12), Madrid, Spain
10Department of Allergy, Hospital Universitari de la Vall d’Hebron, Barcelona, Spain
11Department of Allergy, Hospital de Basurto, Bilbao, Spain
12Department of Allergy, Hospital La Zarzuela, Madrid, Spain
13Department of Allergy, Hospital Vega Baja, Orihuela, Spain
14Department of Allergy, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
15Department of Allergy, Hospital Universitario Central de Asturias, Oviedo, Spain
16Allergy Unit, Pneumology Department, Hospital Clinic, Barcelona, Spain
J Investig Allergol Clin Immunol 2019; Vol 29(6)
Background: The objectives of this study were to investigate the prevalence of sIgE to galactose-α-1,3-galactose (α-gal) in individuals with acute urticaria or anaphylaxis from different geographical areas of Spain and to evaluate the relevance of demographics and lifestyle as risk factors for this immune response.
Methods: Participants were recruited from allergy departments at 14 Spanish hospitals. Patients aged 18 years or older presenting with urticaria or anaphylaxis were enrolled into one of 2 arms: cases and controls. An interviewer-administered questionnaire collecting demographic data, lifestyle habits, and the presence of cofactors was obtained from each participant. sIgE to α-gal and total IgE were determined using ImmunoCAP. sIgE levels ≥0.35 kU/L were considered a positive result.
Results: The study population comprised 160 cases and 126 controls. The median age was 44 years. The overall prevalence of a positive result of sIgE to α-gal was 15.7%; this was higher in cases (26.3%) than in controls (2.4%). The sIgE anti–α-gal positivity rate ranged from 37.68% (rural) to 15.38% (semiurban), and 7.85% (urban). The rates of positivity were 46.32%, (Northern), 0.72% (Center), and 0% (Mediterranean). A positive result for sIgE to α-gal was associated with a history of tick bites, participation in outdoor activities, pet ownership, and ingestion of mammalian meats or innards before the onset of symptoms. Only alcohol consumption could be implicated as a cofactor.
Conclusion: Sensitization to α-gal in patients with urticaria or anaphylaxis differs considerably between the 3 geographical areas studied and is related to tick bites.
Key words: α-Gal, Risk factors, Epidemiology, Outdoor activities, Tick bites, Cofactors