Dog ownership and contact during childhood and later allergy development.

The effect of dog ownership during childhood on the development of allergy has been investigated in few studies with conflicting results. The association between dog contact and indoor endotoxin exposure during infancy and the development of allergic sensitisation and atopic disease up to age 6 yrs was investigated. Two ongoing birth cohorts, the German Infant Nutrition Intervention Programme (GINI; n = 1,962) and the Influences of Lifestyle Related Factors on the Human Immune System and Development of Allergies in Children (LISA; n = 1,193), were analysed. In both studies, information on children's contact with dogs and their allergic symptoms and doctor-diagnosed allergic disease were collected during follow-up using questionnaires. Specific immunoglobulin E to common aeroallergens was measured at age 6 yrs. House dust samples were collected at age 3 months and the amount of endotoxin was determined. Dog ownership in early childhood was associated with a significantly lower rate of mixed pollen and inhalant sensitisation but not with dog sensitisation or allergic symptoms and diseases up to age 6 yrs. Regular contact with dogs, without ownership, during childhood was not associated with those health outcomes. No associations were found between house dust endotoxin exposure during infancy and sensitisation outcomes. In conclusion, dog ownership in early childhood protects against the development of inhalant sensitisation and this effect cannot be attributed to the simultaneous exposure to endotoxin.

The co-seasonal application of anti-IgE after preseasonal specific immunotherapy decreases ocular and nasal symptom scores and rescue medication use in grass pollen allergic children.

BACKGROUND: Specific immunotherapy (SIT) and treatment with anti-immunoglobulin (Ig)E antibody are complementary approaches to treat allergic rhinoconjunctivitis, which may be used for single or combined treatment. OBJECTIVE: A randomized, double-blind, placebo-controlled trial was conducted to compare the efficacy of single and combined treatment with SIT and anti-IgE (Omalizumab) in reducing symptom severity and rescue medication use. METHODS: A total of 221 subjects with birch and grass pollen allergic rhinoconjunctivitis aged 6-17 years were analysed during the grass pollen season. Group A (SITbirch + placebo) served as a reference group obtaining no effective treatment for grass pollen allergy. Group B received anti-IgE monotherapy during grass pollen season, group C SIT grass pollen monotherapy, and group D the combined treatment of SIT and Omalizumab. RESULTS: Preseasonal treatment with grass pollen SIT alone compared with SIT with the nonrelated allergen did not reduce symptoms or rescue medication use. Anti-IgE monotherapy significantly diminished rescue medication use and number of symptomatic days. The combined treatment with SIT and anti-IgE showed superior efficacy on symptom severity compared with anti-IgE alone. CONCLUSIONS: Co-seasonal Omalizumab therapy showed considerable effects in children with seasonal allergic rhinitis. The combination of SIT plus Omalizumab was clinically superior to each treatment alone during the first year of observation.