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Local immunotherapy (LIT) with Dermatophagoides extract or placebo were administered to two groups of 11 patients with allergic asthma in a double-blind fashion. All patients received cromolyn sodium (20 rag four times a day) during treatments. Bronchial provocation tests with allergen and methacholine were performed before, 1 week, and 4 weeks after the end of treatments. Symptom score, drug consumption, and peak expiratory flow were monitored daily from 2 weeks before to 4 weeks after treatments. Compared to baseline, early bronchial sensitivity to allergen was significantly reduced both 1 week ( p p

Nonspecific bronchial responsiveness was studied in 23 allergic patients with a history of rhinitis and/or bronchial asthma who underwent fiberoptic bronchoscopy with bronchoalveolar and bronchial lavage (BAL-BL) 4h (Group A) or 24 h (Group B) after an allergen inhalation challenge. In all patients, the dose of methacholine causing an FEV1 fall of 15% (PD15) was determined at baseline, 24 h before allergen challenge. Methacholine bronchial challenge was repeated 1 h before BAL-BL in patients of both groups and again 12 to 14 h after BAL-BL in Group A and 24 h after BAL-BL in Group B. In patients of Group A, the values of methacholine PD15 after BAL-BL were not significantly different from those determined before BAL-BL. This was also the case in patients in whom bronchial responsiveness was increased after allergen challenge. In patients of Group B, methacholine PD15 was significantly decreased after allergen challenge, and this decrease was correlated with the occurrence and the severity of the late asthmatic reaction. Even in patients who showed dual asthmatic reactions and an increased responsiveness after allergen challenge, methacholine PD15 was not further decreased after BAL-BL. These data support the safety of a procedure combining bronchial allergen challenge with BAL-BL, which can be used for studies on the pathophysiology of bronchial asthma.

Bronchial provocation tests with aerosol of birch extract were performed before and after pollen season in 11 sensitized subjects. Changes of methacholine bronchial responsiveness and serum-specific IgE level were also assessed. In five patients who did not take steroids to control their symptoms, both early and late asthmatic responses to inhaled allergen were enhanced after season, whereas IgE serum level, but not methacholine sensitivity, was significantly increased. In six patients who needed steroids, neither responses to allergen nor IgE serum level and methacholine sensitivity were significantly changed after season. For the whole group, the increase in immediate bronchial sensitivity to allergen was positively correlated with the increase in specific IgE antibodies. We conclude that seasonal exposure to pollen has, in sensitized patients, a priming effect on bronchial mucosa that may be blunted by steroid treatment. The increased production of specific IgE antibodies appears to be an important mechanism for this priming effect.

Twelve patients with asthma sensitized to Dermatophagoides pteronyssinus and Parietaria judaica were studied. Patients were challenged before (winter), during (summer), and after (autumn) Parietaria-pollen season. Early asthmatic reaction was positive for both allergens, and the provocative dose causing a 15% decrease of FEV1 was similar in all seasons. The provocative dose of methacholine causing a 15% decrease of FEV1 and specific IgEs for both allergens were also not significantly different throughout the time of study. Late asthmatic reaction (LAR) to Dermatophagoides occurred in eight of 12 patients in winter, in six of nine in summer, and in five of six patients in autumn. The severity of LAR, expressed as the maximum fall of FEV1 3 to 8 hours after challenge, was not significantly different between seasons. LAR to Parietaria occurred in only one of 12 patients in winter, in six of 11 in summer, and in one of six patients in autumn. In summer, LAR to Parietaria was significantly more severe than in winter. In both winter and autumn, but not in summer, LAR to Dermatophagoides was significantly more severe than to Parietaria. We conclude that LAR is allergen specific, and natural exposure has a priming effect on LAR.

Local immunotherapy (LIT) with Dermatophagoides extract or placebo were administered to two groups of 11 patients with allergic asthma in a double-blind fashion. All patients received cromolyn sodium (20 mg four times a day) during treatments. Bronchial provocation tests with allergen and methacholine were performed before, 1 week, and 4 weeks after the end of treatments. Symptom score, drug consumption, and peak expiratory flow were monitored daily from 2 weeks before to 4 weeks after treatments. Compared to baseline, early bronchial sensitivity to allergen was significantly reduced both 1 week (p less than 0.0005) and 4 weeks (p less than 0.01) after LIT but not after placebo administration. Late bronchial reaction to allergen occurred similarly after placebo administration and LIT. However, in the group with LIT, the severity of late reaction was unchanged after treatment in spite of the significantly larger doses of allergen administered to provoke the early asthmatic reaction. Neither symptom score, nor drug consumption, nor peak expiratory flow were significantly different in the two groups before and during the treatment period even though both symptom score and drug consumption tended to be reduced after LIT. We conclude that LIT may be an effective and safe alternative to traditional immunotherapy.

The relationship between airway responsiveness to methacholine and inflammatory cells in bronchoalveolar lavage (BAL) was determined in patients with history of rhinitis and/or mild bronchial asthma either at baseline (10 patients) or 3-4 h after allergen inhalation challenge (11 patients). At baseline, airway responsiveness did not correlate with any BAL cell population. When data obtained after allergen challenge were included in the analysis, 44% of the variability of airway responsiveness was explained by a multiple regression model with BAL eosinophils as a directly correlated (P = 0.002) independent variable and with BAL macrophages as an inversely correlated (P = 0.045) independent variable. Changes in airway responsiveness after allergen challenge were predicted (82% of variance explained) by a model with BAL eosinophils and BAL lymphocytes as directly correlated (P = 0.0002 and P = 0.03, respectively) independent variables. We conclude that, in stable asymptomatic asthma, baseline airway responsiveness does not correlate with the presence in the airways of inflammatory and immunoeffector cells that can be recovered by BAL. Nevertheless the allergen-induced increase in airway responsiveness is associated with an influx of eosinophils and lymphocytes in the bronchial lumen.

This update on treatment of asthma exacerbations in children is the result of an Italian Pediatric Society Task-force, made up of a panel of experts working in 2007–2008. The aim is to give clear indications on the use of the drugs most employed in children, grading the quality of evidence and the strength of recommendations. Suggestions on their limits due to unlicensed and off-label use are reported. The level of evidence and the strength of recommendations for different therapeutic approaches demonstrate that frequently the use of drugs in children is extrapolated from the experience in adults and that more studies are required to endorse the correct use of different drugs in asthmatic children.