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.

Effect of anti-immunoglobulin E on nasal inflammation in patients with seasonal allergic rhinoconjunctivitis.

BACKGROUND: Binding of allergens to IgE on mast cells and basophils causes release of inflammatory mediators in nasal secretions. OBJECTIVE: The combined effect of specific immunotherapy (SIT) and omalizumab, a humanized monoclonal anti-IgE antibody, on release of eosinophilic cationic protein (ECP), tryptase, IL-6, and IL-8 in nasal secretion was evaluated. METHODS: Two hundred and twenty five children (aged 6-17 years) with a history of seasonal allergic rhinoconjunctivitis induced by birch and grass pollen were randomized into four groups: either birch- or grass-pollen SIT in combination with either anti-IgE or placebo. Complete sets of nasal secretion samples before treatment Visit 1 (V1), during birch- (V2) and grass (V3)-pollen season and after the pollen season (V4) were collected from 53 patients. RESULTS: A significant reduction in tryptase only was seen in the anti-IgE-treated group at V2 (P<0.05) and V4 (P<0.05) compared with the placebo group. During the pollen season, patients with placebo showed an increase of ECP compared with baseline (V2: +30.3 microg/L; V3: +134.2 microg/L, P< 0.005; V4: +79.0 microg/L, P< 0.05), and stable levels of tryptase, IL-6 and IL-8. Treatment with anti-IgE resulted in stable ECP values and a significant decrease of tryptase compared with V1 (baseline): V2: -80.0 microg/L (P< 0.05); V3: -56.3 microg/L, which persisted after the pollen season with V4: -71.6 microg/L (P< 0.05). After the pollen season, a decrease of IL-6 was observed in both groups (V4 placebo group: -37.5 ng/L; V4 anti-IgE group: -42.9 ng/L, P< 0.01). CONCLUSION: The combination of SIT and anti-IgE is associated with prevention of nasal ECP increase and decreased tryptase levels in nasal secretions.

Natural history of hay fever and pollen sensitization, and doctors' diagnosis of hay fever and pollen asthma in German schoolchildren.

BACKGROUND: In order to prevent pollen asthma by immunotherapy it is mandatory to know the best time to initiate it. Children with hay fever complaints are at considerable risk of developing pollen asthma. Population-based data on their natural history is urgently needed. METHODS: A longitudinal cohort study was conducted over four years in six rural towns in Baden-Württemberg, Germany. A questionnaire with questions taken from the International Study of Asthma and Allergies in childhood (ISAAC) was filled in every spring and autumn. Hay fever complaints, asthma defining symptoms and new doctors' diagnosis of hay fever and asthma were recorded. Additionally a skin prick test with pollen allergens was performed every autumn. RESULTS: In 1996, 19.7% of 1101 elementary school children (age: 8.1-9.9 years (5-95%)) were found to be sensitized to pollen and 8.7% had already been diagnosed as having hay fever. In a pooled analysis of 2478 children-summers, children with positive pollen sensitization had a significantly higher risk of developing hay fever symptoms (2.63; 2.17-3.10 odds ratio (OR); 95% confidence interval (CI)) and of being diagnosed as suffering from hay fever (7.88; 4.70-13.20). Furthermore, although their OR for the development of asthma symptoms during the pollen season was 3.88 (2.48-6.07 CI), it was only 0.69 (0.24-2.01 CI) for doctors' diagnosis of pollen asthma. CONCLUSION: Children of elementary school age with pollen sensitization and a history of hay fever are at considerable risk of getting pollen asthma, but they are not quickly diagnosed as such. Specific immunotherapy might be a means of preventing asthma completely in such a situation. Our data helps to estimate the sample size for intervention studies of this kind.

Association of allergy-related symptoms with sensitisation to common allergens in an adult European population.

BACKGROUND: Atopy is an important risk factor for asthma and allergic diseases. However, the relationship between atopy and allergic symptoms is not fully understood, and may not be the same for different allergy related symptoms and in differing environmental conditions. OBJECTIVE: To study the differences in the association of allergy-related symptoms and atopy, in an adult population from five European countries. METHODS: A prospective, multi-national study was conducted. Centres included Isle of Wight (UK), Vienna (Austria), Freiburg (Germany), Athens (Greece), and Kaunas (Lithuania). We used five questions derived from the ISAAC (International Study of Asthma and Allergy in Children) and other validated questionnaire, to evaluate the presence of allergic symptoms in a selected adult population. Atopy was assessed by SPT or IgE measurement to 3 core allergens (dust mite, cat and grass pollen) in all centres and 1-2 additional allergens relevant to each area (parietaria, olive, birch pollen, tree pollen mix, dog). RESULTS: Of 3985 subjects, 2478 (62%) responded positively to one or more core ISAAC questions. Sensitisation rate was high in Austria and UK and relatively low in Greece. Dust mite and cat were important allergens for asthma, odds ratio (OR): 2.24, 95% confidence interval (CI): 1.63-3.08 and OR: 2.31, CI: 1.69-3.14, respectively. Grass pollen was strongly associated with hay fever in all centres (OR: 3.62 CI: 2.81-4.66) and with birch pollen in Austria (OR: 3.57, CI: 2.09-6.09) and with parietaria in Greece (4.61 (2.99-7.12). In the comparative analysis, using UK as a reference, Lithuanians had a 10-20-fold reduced risk of asthma and hay fever, but were twice more likely to report chronic itching. The risk of dust mite allergy was 3- and 10-fold lower in Lithuania and Greece, respectively, whereas the risk of cat and grass pollen allergy was one and half times higher in Austria. CONCLUSION: The risk of allergic symptoms and sensitisation and their association vary widely in different European countries.

The most common phenotypes of sensitization to inhalant allergens in childhood.

BACKGROUND: Atopic individuals are frequently sensitized to a limited number of certain allergens, although most of them are exposed to multiple inhalant allergens in daily life. OBJECTIVE: We investigated the hypothesis that observed common patterns of sensitization might occur with similar frequency within two independent study populations of school-children. METHODS: The results were derived from skin-prick tests conducted on two large samples of children (study 1: n = 583; study 2: n = 1099) examined with the same panel of six inhalant allergens. RESULTS: In order to ensure that the comparison was uniform, the younger subpopulation of study 1 (n = 147) was compared with the sample of study 2 (n = 374). The highest frequency for monosensitization was found for sensitization to Dermatophagoides pteronyssinus (study 1: 18.4%, study 2: 20.3%), followed by monosensitization to grass pollens (study 1: 12.2%; study 2: 8.8%). Using multiple logistic regression for each specific sensitization, a significantly increased relative risk of sensitization to hazel pollens (study 1 OR 5.9; study 2 OR: 24.3) appeared to be associated with sensitization to birch pollens. The same applied to dog dander (study 1 OR: 7.3; study 2 OR: 2.6), which showed an association with sensitization to cat dander. CONCLUSION: In summary, our data suggest that certain clusters of monosensitization and polysensitization to common inhalant allergens exist among a given population. This may well be a reflection of diversity in disposition to specific sensitization and/or antigen crossreactivity. From a practical point of view the data also might help in counselling parents of allergic children.