Coseasonal sublingual immunotherapy reduces the development of asthma in children with allergic rhinoconjunctivitis.

BACKGROUND: We wondered whether short-term coseasonal sublingual immunotherapy (SLIT) can reduce the development of asthma in children with hay fever in an open randomized study. OBJECTIVE: We sought to determine whether SLIT is as effective as subcutaneous immunotherapy in reducing hay fever symptoms and the development of asthma in children with hay fever. METHODS: One hundred thirteen children aged 5 to 14 years (mean age, 7.7 years) with hay fever limited to grass pollen and no other clinically important allergies were randomized in an open study involving 6 Italian pediatric allergy centers to receive specific SLIT for 3 years or standard symptomatic therapy. All of the subjects had hay fever symptoms, but at the time of study entry, none reported seasonal asthma with more than 3 episodes per season. Symptomatic treatment was limited to cetirizine, loratadine, nasal budesonide, and salbutamol on demand. The hay fever and asthma symptoms were quantified clinically. RESULTS: The actively treated children used less medication in the second and third years of therapy, and their symptom scores tended to be lower. From the second year of immunotherapy, subjective evaluation of overall allergy symptoms was favorable in the actively treated children. Development of asthma after 3 years was 3.8 times more frequent (95% confidence limits, 1.5-10.0) in the control subjects. CONCLUSIONS: Three years of coseasonal SLIT improves seasonal allergic rhinitis symptoms and reduces the development of seasonal asthma in children with hay fever.

Safety of sublingual immunotherapy in children with asthma.

INTRODUCTION: Two previously published studies on sublingual immunotherapy (SLIT) did not report any serious adverse event associated with the local therapy; however, adverse events were observed in greatly variable percentages. The aim of the study was to evaluate the tolerability profile of sublingual swallow and spit immunotherapy in a large number of children treated for allergic asthma. METHODS: Adverse effects related to sublingual administration of allergen vaccines were evaluated in 354 children with allergic asthma. Each patient was followed for at least 37 months and received a monthly dose of major allergens (extract) in the range of 1.5-14.8mug, equivalent to 3-20 times the amount contained in the usual monthly maintenance injections via the subcutaneous routes. RESULTS: No adverse event was observed in 90.4% of the children. We observed 0.155 mild to moderate reactions per 1000 administrations. Dosage adjustment was required in 15 patients. In five children, immunotherapy was stopped as a precaution - one patient developed rhino-conjunctivitis, two patients developed urticaria, and two children developed wheezing. None of the reactions were due to dosage errors. No anaphylactic reaction or multiple-organ life-threatening events occurred. CONCLUSIONS: The results of our study showed an incidence of mild to moderate unwanted effects of 9.6%, lower than that previously reported, and no life-threatening adverse effects. Nevertheless, asthma, urticaria, and rhinoconjunctivitis can occur. SLIT is quite a safe therapy for the treatment of allergic children with asthma; however, careful evaluation of the single patient is necessary since SLIT is self-administered and a cumulative monthly dose higher than that normally administered as an injection is usually attainable.

Skin reactivity to histamine and to allergens in unselected 9-year-old children living in Poland and Italy.

Several studies have shown a higher prevalence of positive skin-prick tests to airborne allergens in Western than in Eastern European countries. We have recently reported that skin histamine reactivity significantly increased in Italy over the past 15 years. Population differences in skin histamine reactivity could, at least in part, explain the reported differences in positive allergen skin tests. To test this hypothesis we compared histamine skin reactivity and the prevalence of allergen positive skin-prick tests in a sample of Italian and Polish schoolchildren. A total of 336 unselected 9-year-old-schoolchildren (198 in Italy and 138 in Poland) underwent skin-prick tests with three different histamine concentrations (10, 1 and 0.2 mg/ml) and with a panel of common airborne allergens according to the ISAAC protocol, phase two. Mean wheals elicited by skin-prick tests with the three serial concentrations of histamine were significantly larger (p < 0.001) and shifted more toward higher values (p < 0.001) in Italian than in Polish children. The differences were greater for the intermediate histamine concentration tested (1 mg/ml) than for the highest concentration (10 mg/ml). Skin-prick tests for airborne allergens were more frequently positive in Italian children: wheals >or= 3 mm induced by any allergen [odds ratio (OR) 1.69; confidence interval (CI) 0.98-2.92] by Dermatophagoides pteronyssinus (OR 1.92; CI 0.97-3.80) and by D. farinae (OR 3.15; CI 1.16-8.63). Labeling as positive allergen wheal reactions half the size of the 10 mg/ml histamine wheal or larger reduced but did not abolish the Italian-Polish differences. The significantly higher skin histamine reactivity observed in Italian children could help to explain why allergen skin-test reactions differ in the East and West European populations. Moreover, differences in nonallergen-specific factors among populations should be considered in the interpretation of skin test results (e.g. cut-off points). To obtain meaningful results, epidemiological studies of allergies should include serial histamine dilutions.

Changes in inflammatory and clinical parameters and in bronchial hyperreactivity asthmatic children sensitized to house dust mites following sublingual immunotherapy.

UNLABELLED: In allergic patients with rhinoconjunctivitis (RNC), sublingual immunotherapy (SLIT) is effective in reducing both clinical symptoms and immuno-mediated local inflammatory responses. The study evaluates whether SLIT could reduce upper airway inflammation and improve clinical parameters also in children with rhinoconjunctivitis and asthma from house dust mite sensitization. Ten children with mild to intermittent asthma, monosensitized to house dust mites, received SLIT (Der p 1 monthly dose = 48 microg) for 2 years, in addition to "as needed" pharmacologic treatment. Before (T0) and after treatment (T2), changes were evaluated in (1) nasal eosinophilia, (2) intercellular adhesion molecule (ICAM)-1 expression by nasal epithelial cells, (3) RNC, asthma, and drug-intake scores, assessed by diary card, (4) pulmonary function parameters, and (5) bronchial reactivity to methacholine (MCh). RESULTS: All children completed the study without side or adverse effects. After the treatment period, we found no modification in nasal eosinophil values in mean fluorescence channel percentages, but a significant downregulation in ICAM-1 expression by nasal epithelial cells [mean (mfc): T0: 13.5 +/- 3.8 mfc; T2:4.6 +/- 0.5 mfc; p = 0.04]. These changes were associated with a reduction in RNC score [median values: T0: 3.4 (1.4-6.2); T2: 1.1 (0.6-2.4) p = 0.012], asthma score [median values: T0: 0.5 (0.4-1.0); T2: 0.3 (0.1-0.5); p = 0.005] and drug-intake score [median values: T0: 4.2 (3.1-5.3); T2: 1.1 (0-3.0); p = 0.005]. These clinical effects were not associated with changes in pulmonary function parameters (p > 0.05), but with improvement in bronchial reactivity to MCh [mean values: T0: 338.8 (91.5-1255.5); T2: 1698.2 (1,110.5-2,597.1); p = 0.02]. To what extent these observations may be related to the natural improvement of respiratory allergy symptoms with age remains to be determined.

Efficacy of dry-cleaning in removing Fel d 1 allergen from wool fabric exposed to cats.

BACKGROUND: The main cat allergen (Fel d 1) is ubiquitous, having been found even in indoor environments and public places where a cat has never been kept. Clothes of cat owners constitute a carrier for the distribution of Fel d 1 allergen in these environments. Schools, for example, may be a site of indirect exposure to cat allergens. OBJECTIVE: Our goal was to investigate the efficacy of commercial dry-cleaning in removing cat allergens from wool fabrics that had been exposed to cats to evaluate a possible preventive procedure. METHODS: Twenty-six identical wool "squares" (80 x 100 cm) were put in cat baskets for 1 week. In our laboratory, the squares were cut in half (40 x 50 cm), and one half was subjected to high-volume sampling for 5 minutes in a cat-free room. The other half was subjected to commercial dry-cleaning and then the high-volume sampling. Five wool squares not exposed to cats served as controls. Dust was collected from the wool squares with a high-volume air sampler. Particulate material was harvested onto glass fiber filters (AP 20 Millipore, Milan, Italy) with 25-mm diameter and 2-microm pore size. Each dust sample was assayed by affinity-purified monoclonal antibody against purified Fel d 1. The results were expressed as micrograms per filter. Statistical analysis was done by using the paired t test. RESULTS: Before dry-cleaning, Fel d 1 allergen was detected on all cat-exposed wool squares. No appreciable cat allergen was detected on control materials. After commercial dry-cleaning, the amounts of Fel d 1 extracted from cat-exposed squares were significantly reduced (t = 14.63; P < 0.001) but not abolished. Three of the five control squares were contaminated by Fel d 1. CONCLUSIONS: Commercial dry-cleaning effectively removes large amounts of cat allergen from wool materials exposed to cats but does not completely abolish this protein. Further, low Fel d 1 contamination may occur during this procedure.