Horse allergens: An underestimated risk for allergic sensitization in an urban atopic population without occupational exposure

• Published in: Respiratory medicine 2009-03, Vol.103 (3), p.414-420
• Main Authors: Liccardi, Gennaro, Salzillo, Antonello, Dente, Bruno, Piccolo, Amedeo, Lobefalo, Gaetano, Noschese, Paolo, Russo, Maria, Gilder, Jean Ann, D'Amato, Gennaro
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Allergens - blood; Allergens - immunology; Allergic sensitization; Animal Husbandry; Animals; Animals, Domestic - immunology; Biological and medical sciences; Bronchial asthma; Child; Child, Preschool; Chronic obstructive pulmonary disease, asthma; Environmental Exposure; Female; Hobbies; Horse allergens; Horses - immunology; Humans; Hypersensitivity; Hypersensitivity - immunology; Immunoglobulin E - blood; Male; Medical sciences; Middle Aged; Non tumoral diseases; Otorhinolaryngology. Stomatology; Pneumology; Pulmonary/Respiratory; Respiratory allergy; Rhinitis; Risk Factors; Skin Tests - methods; Upper respiratory tract, upper alimentary tract, paranasal sinuses, salivary glands: diseases, semeiology; Urban Population; Young Adult
• ISSN: 0954-6111; 1532-3064
• DOI: 10.1016/j.rmed.2008.09.017

Summary Background Data on allergic sensitization to horse allergen in modern urban areas are scarce. The aim of this study was to investigate the characteristics of allergic sensitization and the modality of exposure to horse allergens in atopic patients living in an urban area and without occupational exposure to horse and/or horse-derived materials. Methods From among 1822 consecutive outpatients, we selected all subjects who had an immediate skin reaction to horse dander. We recorded the patients' clinical history including a meticulous evaluation of the possibility and eventual modality of horse exposure, and the results of skin-prick tests (SPT) and total/specific IgE antibody analyses. Results Of 1201 SPT-positive patients, 35 (3.43%) were sensitized to horse dander. No patient was mono-sensitized. Six individuals reported having direct horse contact, 10 subjects had occasional contact with horse owners (indirect exposure), and 19 denied direct or indirect exposure to horses or horse allergens. Twenty of the 35 horse-sensitized patients reported both nasal and bronchial symptoms, 14 had rhinitis without asthma and one had asthma without rhinitis. Conclusions Our results suggest that allergic sensitization to horse allergens is more frequent than expected in urban-dwelling subjects without direct or occupational exposure to horses. Highly atopic individuals or individuals who are sensitized to common pet dander should undergo SPT and evaluation of serum specific IgE before starting activities involving regular contact with horses such as riding, and before entering environments associated with horses.