Prevalence of asthma, allergic rhinoconjunctivitis and allergic sensitization in Mongolia

BACKGROUND: Studies in countries, such as Mongolia, which are in transition from farming to industrial society permit evaluation of the impact of environmental change on atopic diseases. METHODS: In the screening study, questionnaire data were obtained from 9453 subjects aged 10-60 years. In the clinical study, a subsample of 869 subjects (participation rate 50.0%) was examined. A questionnaire-based interview, clinical examination, skin prick tests, spirometry and bronchodilation test or methacholine challenge test were used to define the clinical diagnoses. The prevalences of atopic diseases were evaluated at the population level using two-phase data and sampling weights. RESULTS: The prevalences of asthma, allergic rhinoconjunctivitis and allergic sensitization with 95% confidence intervals were 1.1% (0.3-2.0%), 9.3% (4.0-14.6%) and 13.6% (7.4-19.9%) in Mongolian villages, 2.4% (1.4-3.5%), 12.9% (8.2-17.7%) and 25.3% (17.1-33.6%) in rural towns and 2.1% (1.3-3.0%), 18.4% (13.3-23.4%) and 31.0% (24.5-37.5%) in Ulaanbaatar city, respectively. The prevalence of allergic rhinoconjunctivitis (P = 0.02) and allergic sensitization (P = 0.003) increased significantly with increasing urbanization. CONCLUSIONS: The prevalences of atopic diseases were low in rural Mongolia and increased with increasing urbanization suggesting that rural living environment protects against atopy.     

A Comparative Study of Dexchlorpheniramine Maleate Sustained Release Tablets and Budesonide Nasal Spray in Seasonal Allergic Rhinitis

It was the aim of the study to compare the efficacy and side effects of oral antihistamine and nasal glucocorticoid therapy in seasonal allergic, rhinitis. In a double blind, double-dummy, group-comparative study, 61 adult grass pollen allergic patients were either treated with dexchlorpheniramine maleate sustained release tablets (6 mg b.d.), or with budesonide nasal spray (200 micrograms b.d.). After a 1-week run-in period, treatment was given for 3 weeks in the grass pollen season. Patients treated with budesonide showed significantly less nasal blockage than those who received dexchlorpheniramine (P less than 0.05), but there was no difference in the number of sneezes and nose blowings. Patients treated with budesonide and a larger quantity of antihistamine-vasoconstrictor eye drops (P less than 0.01). Drowsiness occurred in the group that was treated with dexchlorpheniramine, but mainly during the first week of treatment. The side effects caused by the budesonide spray were few and insignificant. The patients' overall assessment of the treatment favoured the glucocorticoid spray (P = 0.06).     

Sinus CT scans and mediator release in nasal secretions after nasal challenge with cypress pollens

BACKGROUND: Involvement of paranasal sinuses has been suggested in allergic rhinitis but not clearly demonstrated. AIMS: To investigate the relationship between intermittent allergic rhinitis and computerized tomography (CT). METHODS: Twenty patients with intermittent rhinitis and sensitized to cypress pollens underwent unilateral nasal provocation tests (NPTs) using increasing concentrations of cypress pollens out of the pollen season. Sinus CT-scans were carried out just before a NPT and 24 h later. Nasal lavage was carried out just before a NPT, 30 min after a positive challenge and again 24 h later. Leucotriene C4/D4, intracellular adhesion molecule-1 and eosinophil cationic protein were measured in nasal secretions. RESULTS: Thirteen patients (65%) showed an alteration in their CT-scans after allergen challenge. Ten of them showed sinus changes controlateral to their allergenic provocation. Radiological changes mainly affected the osteomeatal complex and the ethmoid sinuses. Pre-existing abnormalities (13 of 20 cases) mainly concerned the maxillary sinuses. There was no correlation between CT-scan abnormalities and levels of mediators released in nasal secretions. CONCLUSIONS: We have shown that nasal allergen challenge can produce radiological changes in the paranasal sinuses. This mainly concerned the ethmoid sinuses.     

Allergen-reactive antibodies are found in nasal fluids from patients with birch pollen-induced intermittent allergic rhinitis,but not in healthy controls

BACKGROUND: Increased levels of allergen-reactive immunoglobulins (Igs) have been reported in nasal fluids from patients with intermittent allergic rhinitis (IAR) sensitive to ragweed and grass. The aims of this study were to make a detailed characterization of nasal fluid Igs in birch pollen-induced IAR. METHODS: Nasal fluids were obtained from 23 patients with birch pollen-induced IAR during and after the birch pollen season, and from 20 healthy controls. Nasal fluid total and Bet v 1-reactive (IgA), IgE and IgG as well as albumin were analyzed by immunoassays. The integrity of IgA and IgG, and the molecular form of IgA were assessed by Western blotting and column fractionation, respectively. RESULTS: Nasal fluid total IgE and IgG, but not IgA, were higher in patients compared with controls. Western blotting indicated no significant degradation of IgA (including S-IgA) and IgG. Most of the IgA, including Bet v 1-reactive antibodies, was of the secretory form and of the IgA1 subclass. Bet v 1-reactive IgA and IgG were present in all patients, but was mostly nondetectable in controls. No significant differences in the levels of Bet v 1-reactive IgA and IgG were found in patients during the birch pollen season compared with off season. Both Bet v 1 and Bet v 2-reactive IgE were nondetectable in most samples. CONCLUSIONS: Nasal fluid Bet v 1-reactive IgA and IgG were found in all patients with birch pollen-induced IAR, but not in controls. However, no significant differences were found between patients during and after the birch pollen season.     

Intranasal and inhaled fluticasone propionate for pollen-induced rhinitis and asthma

BACKGROUND: Studies suggest that nasal treatment might influence lower airway symptoms and function in patients with comorbid rhinitis and asthma. We investigated the effect of intranasal, inhaled corticosteroid or the combination of both in patients with both pollen-induced rhinitis and asthma. METHODS: A total of 262 patients were randomized to 6 weeks' treatment with intranasal fluticasone propionate (INFP) 200 microg o.d., inhaled fluticasone propionate (IHFP) 250 microg b.i.d., their combination, or intranasal or inhaled placebo, in a multicentre, double-blind, parallel-group study. Treatment was started 2 weeks prior to the pollen season and patients recorded their nasal and bronchial symptoms twice daily. Before and after 4 and 6 weeks' treatment, the patients were assessed for lung function, methacholine responsiveness, and induced sputum cell counts. RESULTS: Intranasal fluticasone propionate significantly increased the percentages of patients reporting no nasal blockage, sneezing, or rhinorrhoea during the pollen season, compared with IHFP or intranasal or inhaled placebo. In contrast, only IHFP significantly improved morning peak-flow, forced expiratory volume in 1 second (FEV1) and methacholine PD20, and the seasonal increase in the sputum eosinophils and methacholine responsiveness. CONCLUSIONS: In patients with pollen-induced rhinitis and asthma, the combination of intranasal and IHFP is needed to control the seasonal increase in nasal and asthmatic symptoms.     

Rhinoconjunctivitis,bronchial responsiveness,and atopy as determinants for incident non-work-related asthma symptoms in apprentices exposed to high-molecular-weight allergens

OBJECTIVE: The aim of this study was to explore the role of rhinoconjunctivitis (RC), taking into account atopy and the level of bronchial responsiveness to methacholine, on the incidence of respiratory symptoms and in the development and/or worsening of asthma. METHODS: We examined data from a prospective study in 769 students starting exposure to high-molecular-weight occupational allergens and who were serially followed for up to 44 months. RESULTS: The presence of RC symptoms at baseline was significantly associated with an increased risk of developing shortness of breath and wheezing in atopic subjects regardless of PC20 level and in subjects with a PC20 相似文献   

Environmental priming influences allergen-specific nasal reactivity

Background Preceding mucosal response to one allergen leads to the priming of the nasal mucosal response to another allergen. This study aimed t o determine whether environmental allergens, especially ubiquitous animal dander, can induce nasal priming.
Methods We investigated 26 grass-pollen-allergic subjects with additional sensitization to other aeroallergens. We performed continuous allergen challenge for 2 h with 1500 Dactylis glomerata pollen/m³ in the Vienna challenge chamber. The nasal flow at 150 Pa was examined, and subjective scores were obtained every 15 min. Statistical analysis was calculated from the area under curve of nasal flow reduction by Student's f-test and the Mann-Whitney U-test. Alpha was 0.05.
Results In subjects with positive cat-dander RAST (class of ≥ 3), besides grass-pollen allergy, the specific nasal allergic reaction to Dactylis challenge was significantly pronounced (P <0.01). and an earlier onset of reaction was evident. TTie same results were obtained with additional sensitization to dog dander (P<0.05). Concomitant sensitization to mugwort also led to escalating symptoms (P<0.05).
Conclusions These results indicate that a specific nasal allergic reaction is augmented by environmental priming caused by ubiquitous animal dander and possibly is influenced by the daily use of spices.