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Biomedical subjects

G L Piacentini

Publications and source records attributed to G L Piacentini.

At least 19 recordsLinked to original sources

Atopy and house dust mite sensitization as risk factors for asthma in children.

BACKGROUND: Recent evidence suggests that asthma is not invariably related to atopy. The aim of this study was to evaluate the frequency of atopy, asthma and sensitization to eight common allergens in a large group of children with allergic symptoms. METHODS: 1426 children referred to our Paediatric Asthma and Allergy Center because of allergic symptoms were examined. Bronchial asthma, allergic rhino-conjunctivitis, food allergy and atopic dermatitis were diagnosed with standardized methods. Atopy was diagnosed if at least one skin test was positive. RESULTS: Of the 1426 children examined, 629 (44%) were atopic and 769 (56%) were non-atopic. Asthma was diagnosed in the same proportion (i.e., 64%) of atopic and non-atopic children. However, after division into age groups, non-atopic asthma was significantly more prevalent (chi2 = 8.46) in children between 0 and 3 years old (group 1). On the other hand, atopy was significantly associated with asthma only in group 3 (odds ratio 1.85). Furthermore, a significant association with asthma symptoms was found for house dust mite (HDM) in group 3 (odds ratio 4.8). CONCLUSIONS: Asthma is related to atopy in pre-selected children only from the age of 7 years. House dust mite sensitization seems to be an important determinant of asthma in these "older" children.

Age Factors↗

Mite avoidance can reduce air trapping and airway inflammation in allergic asthmatic children.

BACKGROUND: We investigated the effects of prolonged allergen avoidance in 18 house dust mite-sensitized asthmatic children during a prolonged residential period at a high altitude, allergen-free environment. METHODS: Evaluations of residual volume (RV) and exhaled nitric oxide (eNO) were performed (i) at admission to the residential house in September, (ii) in December after 3 months of stay, (iii) in January after 15 days at home, exposed to allergens, and (iv) in June after 9 months of stay. RESULTS: During the study period RV showed a significant decrease in December (from 117.5 +/- 7.7% to 96.5 +/- 3.2%) (P < 0.02) and a following increase in January (126.2 +/- 17.2%), after allergen re-exposure (P < 0.03). RV decreased again in June at the end of the study period (91.1 +/- 6.0%) (P = 0.001). FEV(1), FEF(25-75) and VC values did not present significant variations. ENO showed a significant decrease in December after 3 months at high altitude (from 21.3 +/- 3.9 p.p.b. to 11.9 +/- 1.7 p.p.b.) (P = 0.03), but no further significant change. No correlation was found between lung volumes and eNO, probably reflecting different aspects of asthma. CONCLUSIONS: Results suggest that RV may be more sensitive than other respiratory function parameters in identifying children with air trapping, being influenced significantly as the inflammatory indices by effective allergen avoidance/exposure regimen.

Adolescent↗

Reduction in exhaled nitric oxide immediately after methacholine challenge in asthmatic children.

BACKGROUND: The measurement of exhaled nitric oxide (NO) has recently been proposed as a useful technique for the evaluation of airway inflammation in asthma. The purpose of this study was to determine the effect of methacholine bronchial provocation on the levels of exhaled NO in asthmatic children. METHOD: Exhaled NO was measurement immediately before and after methacholine provocation in 51 children with mild to moderate asthma. RESULTS: A significant decrease occurred in the level of exhaled NO (p<0.0001) after methacholine bronchial provocation which was not correlated with the percentage fall in forced expiratory volume in 1 second (FEV(1)). CONCLUSIONS: The methacholine test should not be used immediately before measurement of exhaled NO in children with asthma.

Adolescent↗

The combination of single-dose montelukast and loratadine on exercise-induced bronchospasm in children.

The aim of the study was to evaluate the protective effect of single-dose, combination treatment comprising montelukast (5 mg) and loratadine (10 mg), on exercise-induced bronchoconstriction in asthmatic children. The combination was compared to placebo, loratadine and montelukast alone. Nineteen children were enrolled in a double-blind randomised, single-dose, crossover study. For each treatment patients undertook two treadmill exercise tests, 2 and 12 h respectively after single-dose administration. No significant differences were seen in the maximum fall in forced expiratory volume in one second (FEV1) 2 h after treatment and placebo. Whereas significant differences in maximum fall in FEV1 were observed between treatment groups 12 h after administration. Loratadine alone did not show any significant protection or any additional effect in comparison with montelukast alone. Single doses of montelukast and montelukast plus loratadine were significantly more effective than loratadine at 12 h. The present study, performed using single-dose treatments, demonstrated that maximal protective effect by montelukast was obtained 12 h after dosing and that montelukast plus loratadine did not result in significant additive bronchoprotective effects on exercise-induced bronchoconstriction.

Acetates↗

Relationship between exhaled air temperature and exhaled nitric oxide in childhood asthma.

Airway inflammation is a characteristic of asthma. Exhaled nitric oxide (eNO) has been demonstrated to be related to actual levels of airway inflammation in asthmatic patients. The purpose of this study was to investigate whether the temperature of exhaled air is related to eNO levels. Temperature of exhaled air and eNO were measured in 52 asthmatic children with a cross-sectional design. A significant relationship was demonstrated between eNO and temperature of peak and plateau exhaled air temperature. The relationship between both the peak and the plateau values and eNO was more evident when it was corrected for environmental temperature. These results suggest a relationship between exhaled nitric oxide and the temperature of exhaled air in asthmatic patients not treated with systemic steroids.

Adolescent↗

Exhaled nitric oxide is reduced after sputum induction in asthmatic children.

Exhaled nitric oxide (ENO) and eosinophil sputum markers are considered noninvasive markers of airway inflammation in asthma. The aim of this study was to evaluate whether the procedure of sputum induction can affect the level of ENO. We measured ENO before and after sputum induction by inhalation of hypertonic saline solution in 22 asthmatic children and 9 healthy controls. The ENO mean (+/- S. E.M.) value in the group of asthmatic children was reduced from a baseline value of 20.8 (+/- 3.0) ppb to 17.4 (+/- 2.4) ppb after sputum induction (P = 0.0012). In the healthy controls, the mean baseline value of ENO was 9.1 (+/- 2.1) ppb and it was reduced to 4. 8 (+/- 1.1) ppb after induction of sputum (P < 0.01). We suggest that measurements of ENO should be performed after the induction of sputum in asthmatic patients whenever both tests are done in sequence.

Adolescent↗

Exhaled nitric oxide in asthmatic children exposed to relevant allergens: effect of flunisolide.

Inhaled corticosteroids are capable of reducing the level of exhaled nitric oxide (expiratory nitric oxide fraction (FE,NO)) in asthmatic patients in a dose-dependent fashion. The aim of this study was to evaluate whether or not treatment with an inhaled steroid can prevent changes in FE,NO after the exposure to relevant allergens, following avoidance, in asthmatic children allergic to house dust mite. Thirty-two house dust mite-allergy asthmatic children were randomly allocated to treatment with inhaled flunisolide (500 microg b.i.d) or placebo and evaluated before and 2 weeks after a period of natural exposure to mite antigens. Lung function and FE,NO were evaluated. FE,NO was increased in the placebo-treated group after antigen exposure. Treatment with inhaled flunisolide prevented such increase in FE,NO (p<0.001). No change was observed in lung function parameters. Inhaled flunisolide is effective in preventing the increase in airway inflammation observed in allergic asthmatic children re-exposed to allergens.

Administration, Inhalation↗

Exhaled nitric oxide, serum ECP and airway responsiveness in mild asthmatic children.

The purpose of the present study was to assess the possible relationships between exhaled nitric oxide (ENO), a circulating marker of eosinophil activation, serum eosinophil cationic protein (SECP), level of airway responsiveness to methacholine and lung function in asthmatic children, as well as to compare these markers between children with and without inhaled steroid therapy. In a cross-sectional study ENO, SECP and bronchial hyperresponsiveness to methacholine were evaluated in a group of 57 asthmatic children (21 without and 36 with regulator inhaled steroid therapy; aged 6-13 yrs). ENO was significantly lower in steroid treated children (p<0.01). No significant differences between steroid treated and untreated children were observed for the provocative concentration of methacholine causing a 20% fall in forced expiratory volume in one second (FEV1; PC20), SECP and FEV1. In the whole study population significant increase correlations were observed between PC20 and SECP (r=-0.329, p=0.013) and between ENO and FEV1% of predicted (r=-0.348, p<0.01). In the group not receiving inhaled steroids the inverse relationship between PC20 and SECP was more evident (r=-0.581, p<0.001). In the steroid-treated group a significant inverse relationship was observed between ENO and FEV1 (r=-0.426, p=0.0011). The level of exhaled nitric oxide and the relationships between lung function, bronchial reactivity and markers of inflammation are different between steroid-treated and untreated asthmatic children. This has implications for the monitoring of asthma in childhood.

Adolescent↗

Snail anaphylaxis during house dust mite immunotherapy.

This study reports a 12-year-old girl who developed an anaphylactic reaction following snail ingestion during house dust mite (HDM) immunotherapy treatment. Radioallergosorbent (RAST) inhibition showed cross-reactivity between the two allergens, leading to consideration of HDM as the sensitizing agent. Children undergoing HDM immunotherapy treatment should be aware of the potential risks of hypersensitivity reactions to invertebrate foods.

Anaphylaxis↗

Exhaled nitric oxide and sputum eosinophil markers of inflammation in asthmatic children.

Exhaled nitric oxide and eosinophil sputum markers are considered noninvasive ways in which to evaluate airway inflammation in asthma. The aim of this study was to evaluate the relationships between these methods of evaluation in asthmatic children. In a cross-sectional study of 25 mild-moderate asthmatic children (aged 6-13 yrs, 10 patients on inhaled steroids) exhaled NO was measured along with induced sputum by inhalation of hypertonic saline solution. The sputum was processed for eosinophil count and eosinophil cationic protein (ECP) determination. Serum ECP and lung function (forced expiratory volume in one second (FEV1)) were also measured. A significant correlation was observed between exhaled NO and sputum eosinophils (r = 0.438, p = 0.032) as well as between sputum eosinophils and sputum ECP (r = 0.532, p<0.01). No correlation was observed among exhaled NO and serum ECP, sputum ECP, FEV1, respectively. Furthermore no correlation was observed between sputum eosinophil (%) and serum ECP and between sputum eosinophils and FEV1. There was no correlation among the investigated parameters in children treated with inhaled steroids. In conclusion, exhaled NO and sputum eosinophil counts are concordant in evaluating the degree of airway inflammation in patients with mild-to-moderate asthma. However, the association between these two noninvasive markers becomes less in steroid treated patients.

Adolescent↗

Mite-antigen avoidance can reduce bronchial epithelial shedding in allergic asthmatic children.

BACKGROUND: Asthma is characterized by bronchial hyperresponsiveness (BHR), bronchial mucosa inflammation and airway epithelial damage. OBJECTIVE: This study was designed to evaluate the effect of mite avoidance on bronchial epithelial shedding in asthmatic children sensitized to Dermatophagoides. METHODS: The percentages of airway epithelial cells and eosinophil have been counted in samples obtained by hypertonic saline-induced sputum before and after a period of antigen avoidance in an Alpine environment (1756 m). The degree of bronchial hyperresponsiveness to methacholine was also evaluated. RESULTS: After avoidance the median (lower, Q1, and upper, Q3, quartile) percentage of epithelial cells in the sputum decreased significantly from 3.50 [0.50;6.98] to 0 [0;0.5] (P=0.012) and eosinophil percentage decreased from 1 [0;5.25] to 0 [0,1.5] (P<0.05). Median (Q1,Q3) PC20 increased significantly from 2.75 [1.53;7.5] to 3.25 [1.65;15.25] mg/ mL (P=0.038). After 3 weeks of re-exposure to mite the epithelial median (Q1,Q3) percentage raised to 3.90 [1.5;6] (P = 0.027), eosinophils to 1.5 [0;3.00] (NS) and PC20 was 5.25 [1.68;14.50] (NS). CONCLUSION: Exposure to house dust mite antigen can induce airway epithelial shedding even in subjects with low eosinophil airway infiltration, thus supporting the idea that epithelial damage in asthmatics sensitized to Dermatophagoides may be due to a proteolytic activity of the mite major antigens.

Adolescent↗

Environmental allergens and childhood asthma.

Exposure to allergens has been shown to lead to sensitization and to the subsequent development of airway hyperresponsiveness in genetically predisposed individuals. Increasing interest is being devoted to mechanisms for the prevention of allergen sensitization and asthma development. Primary prevention (avoiding the sensitization to allergens) requires a large effort as the majority of atopic sensitizations occur in children with no demonstrable risk at the birth. Secondary prevention (deterrence of disease expression despite prior IgE sensitization) requires methods for detecting the population at risk by means of large population screening. Tertiary prevention (minimizing the morbidity for those who already have the disease) may be achieved by allergen avoidance, which has been demonstrated to effectively decrease inflammation in symptomatic patients.

Allergens↗