Laura C. Martinati

Antigen avoidance in a mountain environment: Influence on basophil releasability in children with allergic asthma

BACKGROUND The influence of natural antigen avoidance in an environment free of relevant allergens (Istituto Pio XII, Misurina, Italian Alps, 1756 m) and of antigen exposure (sea level) on basophil releasability, as well as on bronchial hyperreactivity (BHR) and specific IgE serum level, were investigated in a group of children with asthma who were allergic to Dermatophagoides pteronyssinus. METHODS Twenty allergic children with asthma participated in the study. Spontaneous and antigen-induced histamine release, BHR, and serum IgE were investigated at the time of admission, after 40 and 80 days of antigen avoidance, and after 15 days of exposure at sea level. RESULTS Significant drops in antigen-induced basophil histamine release, BHR, and specific IgE serum level but not in spontaneous basophil histamine release were observed after 40 days of antigen avoidance and were confirmed at a further evaluation after 40 more days. After 15 days of antigen exposure at sea level, specific antigen-induced basophil histamine release, BHR, and serum IgE but not spontaneous basophil histamine release increased promptly, even if not significantly. CONCLUSION In children with allergic asthma, antigen-induced basophil releasability, BHR, and specific IgE serum levels appear to be modifiable by periods of antigen avoidance or exposure.

Influence of allergen avoidance on the eosinophil phase of airway inflammation in children with allergic asthma

BACKGROUND Exposure to relevant allergens causes an increase in bronchial hyperresponsiveness, as well as an inflammatory reaction at the site of the bronchial mucosa in patients with asthma. OBJECTIVE The purpose of this study was to determine whether antigen avoidance can exert an antiinflammatory effect on the eosinophil phase of airway inflammation in children with asthma. METHODS The level of bronchial hyperreactivity and the percentage of eosinophils in sputum samples obtained by inhalation of hypertonic saline solution, were evaluated in a group of asthmatic children allergic to house dust mite before and after a period of antigen avoidance in an Alpine environment (1756 m). RESULTS At the end of the avoidance period PC20 increased from a median value (lower and upper quartile: Q1, Q3) of 1.17 (0.74, 4.75) to 3.5 (1.18, 8.87) mg/ml (p = 0.02), and eosinophil percentage in the sputum decreased from a median value (Q1, Q3) of 14.02 (3.34, 28.24) to 2.08 (0, 7.4) (p less than 0.01). CONCLUSION A 3-month period of antigen avoidance can significantly reduce the eosinophil phase of airway inflammation, along with bronchial hyperresponsiveness, in patients with asthma.

Association of a Lymphotoxin alpha gene polymorphism and atopy in Italian families.

Tumour necrosis factor (TNF) is a proinflammatory cytokine that increases human airway tissue responsiveness and is considered a candidate gene for asthma. Two common polymorphisms (LTαNcoI and TNFα-308) in the TNF gene complex were studied in 600 subjects from 131 Italian families with atopic asthmatic children. Skin prick test (SPT), total IgE levels, atopy (defined as increased IgE levels or SPT positivity or both), bronchial hyperresponsiveness, and clinical asthma were investigated. The observed distribution of the identical by descent alleles at the LTαNcoI locus was different from expected for SPT and atopy (p=0.015). The LTαNcoI genotype distribution for increased IgE levels was different between males and females (p=0.0011), and an association of the 2.2 genotype with increased IgE levels was observed in females (p=0.0032). The results indicate that the LTα gene, or a closely linked locus, is associated with atopy, and suggest a sex difference in the effect of the gene.

Linkage to atopy on chromosome 19 in north-eastern Italian families with allergic asthma

Background Allergic asthma is a multifactorial disease for which there is a widely assessed, although poorly understood, genetic involvement. Genome‐wide screens reported evidence for linkage of allergic asthma‐related phenotypes to several chromosomal locations. Markers on chromosome 19 have been linked to allergic asthma phenotypes in different populations in independent studies.

The efficacy and tolerability of fluticasone propionate aqueous nasal spray in children with seasonal allergic rhinitis

Fluticasone propionate aqueous nasal spray (FPANS) contains fluticasone propionate, which is a new topically active glucocorticoid with approximately twice the potency of beclomethasone dipropionate. In this European multicentre study, 143 children with seasonal allergic rhinitis were recruited: 47 received FPANS 100 jag once a day (od), 46 received FPANS 200 μg od, and 50 patients received placebo od, for 4 weeks. Treatment efficacy was assessed using diary card nasal symptom scores for sneezing, rhinorrhoea, blockage and itching, and eye watering/irritation. Patients receiving FPANS 100 μg or FPANS 200 μg demonstrated statistically significant improvements in median nasal symptom scores in all the symptoms recorded, when compared with placebo. There were no statistically significant differences between the FPANS 100 μg and FPANS 200 μg groups in improvement in nasal symptom scores. There was no effect on eye watering/irritation symptoms which could be attributed to either FPANS 100 μg or FPANS 200 μg when compared with placebo. Use of rescue antihistamine medication was significantly reduced in the FPANS 100 μg group when compared with placebo. The adverse events profile was similar in all three treatment groups, and the events reported were generally mild and related to the patients’ rhinitis.

Double-blind trial of house-dust mite immunotherapy in asthmatic children resident at high altitude.

Twenty‐three Dermatophagoides pteronyssinus (Dpt)‐sensitive asthmatic children aged 7–14 years entered a double‐blind, placebo‐controlled trial of standardized immunotherapy (IT) (Alpare) while resident at high altitude. Dpt sensitivity was evaluated by skin prick tests at different allergen concentrations at the enrollment and after 6 and 12 months of treatment. Bronchial hyperreactivity was evaluated at the same time points, and on each occasion, histamine challenge and, the following day, Dpt bronchial challenge were performed. All patients, irrespective of active treatment, improved clinically and in lung function with increased PC20 and Dpt‐PD20. Alpare‐treated patients had a significantly decreased sensitivity on Dpt skin testing (P ≤0.009) and felt that their asthma had improved (P ≤0.001) compared with placebo‐treated subjects, but there was no difference between the treatment groups in lung function or bronchial challenge response. IT neither increased nor decreased bronchial histamine sensitivity. Our results indicate that Dpt IT benefits asthmatic children, but improvement by allergen avoidance at high altitude is even greater.

Association of the FcepsilonRIbeta gene with bronchial hyper-responsiveness in an Italian population.

A study of two DNA polymorphisms (i2 RsaI, E237G) in the gene for the beta subunit of the IgE high affinity receptor (FcepsilonRIbeta) was performed in 168 Italian families with atopic asthmatic children. The prevalence of the E237G allele in the Italian population was 4%, so this polymorphism was unsuitable for this study. The i2 RsaI polymorphism minor allele frequency was 44%, and it had a PIC value of 0.37. Linkage analysis indicated a significant allele sharing in affected sib pairs for bronchial hyper-responsiveness (BHR, p=0.048), but not for allergic asthma. These data indicate an association of bronchial hyper-responsiveness with the FcepsilonRIbeta gene.

Nebulized flunisolide in infants and young children with asthma: a pilot study.

The role of nebulized flunisolide solution in controlling recurrent respiratory symptoms was assessed in a double‐blind placebo‐controlled parallel study on 23 infants and small children (mean age, 14 2 months) with bronchial asthma. Five of the 12 children in the placebo group and 1 of the 11 patients on active treatment had to be withdrawn from the study. Flunisolide significantly improved symptom scores of wheezing and cough. The rescue treatments with salbutamol did not differ between the two groups during the study. Parents considered the active treatment effective in all the patients, while the placebo was considered useful in 4 of 7 children. No side effects were detected with either treatments. This study indicates that nebulized flunisolide may be an effective treatment for infants with recurrent wheezing and cough. Pediatr Pulmonol. 1996; 21:310–315.

Optimum Treatment of Allergic Rhinitis in Children

SummaryAllergic rhinitis is a very common disease, occurring in 10% of children and up to 20% of adolescents. The effects of the disease are frequently underestimated and not regarded as a serious health problem. However, if not properly treated, the disease is associated with harmful sequelae and poor quality of life.The treatment of allergic rhinitis in children depends on 3 therapeutic approaches: avoidance of provoking factors, pharmacological therapy and immunotherapy. Environmental control measures should be directed against allergens as well as against nonspecific irritating factors such as tobacco smoke. Conventional therapy depends on the appropriate selection and combination of antihistamines, mast cell stabilisers, decongestants and topical corticosteroids. Immunotherapy must not be used indiscriminately and should be prescribed only when clearly indicated. Compliance with the treatment regimen is an essential element of therapeutic success.