Fluticasone propionate and bronchial hyperresponsiveness in childhood asthma.

Bronchial asthma is now agreed as being a chronic inflammatory disease of the airways. Inhaled steroids are widely accepted as a preventive medication in asthmatic patients of all ages and severity. However, the optimal use of inhaled steroids and the important issue of safety and efficacy still remain of concern, particularly in children. Recently, fluticasone propionate (FP) has been developed for use as an inhaled preparation for the treatment of asthma. Because of its high topical potency and increased lipophilicity, it is claimed that FP has an improved risk/benefit compared with other inhaled steroids. In order to evaluate the use of FP in children, we have studied the efficacy of high dose FP (500 microg/day) in asthmatic children. Thirteen children (9 boys and 4 girls), aged 7-17 years (10.8 +/- 2.6), were instructed to use a pressurized metered-dose inhaler connected to a Volumetric spacer. The standard methacholine bronchial challenge test was used as a principal outcome parameter. The PD20, a cumulative dose of methacholine inducing a 20% decrease in FEV1, was measured pre- and post-treatment with inhaled FP. After 4 weeks of FP, PD20 significantly increased from 21.6 +/- 14.3 inhalation unit to 106.6 +/- 78.5 inhalation unit (4.9 fold, p = 0.004) reflecting the improvement of airway reactivity. All subjects improved clinically. These results demonstrate that the anti-inflammatory action of FP 500 microg a day for four weeks can markedly reduce bronchial hyperresponsiveness, the basic physiologic abnormality in bronchial asthma.

Protective effects of different doses of inhaled fenoterol on methacholine-induced bronchoconstriction in asthmatic children

Objective: To evaluate the protective effect of different doses of inhaled fenoterol (F) on bronchoconstriction induced by methacholine (M). Design: randomized double-blind study. Setting: Referrence center. Participants: 9 children (aged from 7 to 15 years old), with mild or moderate asthma and allergic to D. pteronyssinus. Intervention: On the first day, the M concentration necessary to induce a 20 per cent fall in the forced expiratory volume in the first second (FEV(1); PC(20)FEV(1)) was determined using closed circuit inhalation (De Vilbiss 646). On subsequent days, the children inhaled a dose of F (25 or 50 or 100 or 220 mug) through the same circuit and, after 15 minutes the FEV(1), was measured, becoming the basal value. Bronchoprovocation was then initiated using the concentration prior to the PC(20)FEV(1) of the first day and continuing until there was a 20 per cent fall in the FEV(1). This concentration was the "new" PC(20)FEV(1). Results. F in a dose of 25 mug protected 2 of the 9 children, in a dose of 50 mg protected 4 of the 9 and in doses of 100 and 200 mug protected all children. We did not observe any relationship between the magnitude of the bronchodilation and bronchoprotection induced by the inhalation of F. Conclusions: Our results suggest that a dose of 100 mug of F is capable of inducing bronchoprotection in children with mild/moderate asthma.

Correlación entre atopia e hiperreactividad bronquial inespecífica en niños asmáticos / Correlation between atopy and nonespecific bronquial hyperresponsiveness in asthmatic children

Hiperreactividad bronquial (HRB) y atopia se asocian a menudo en el asma bronquial de la infancia y es cada vez mayor el número de estudios que así lo sugieren. Con la finalidad de cuantificar esa asociación, se estudiaron 35 niños asmáticos atópicos, entre 7 y 16 años, divididos en tres grupos de acuerdo con la severidad clínica-leve, moderada y severa. Material y métodos: Se determinó el grado de reactividad bronquial por inhalación de metacolina (PC20 VEF1 en mg/ml), pruebas cutáneas con aeroalergenos por método escarificación e IgE sérica total (en Ul/ml) por radioinmunoanálisis (RIA). Como parámetro principal de atopia se establecieron dos puntajes de pruebas cutáneas (PPC): PPc1: número de antígenos positivos (pápula igual o mayor de 3mm) y PPC2: suma de los diámetros (mm) de las pápulas generadas por los antígenos positivos. Resultados: Se observaron diferencias significativas para cada una de las variables estudiadas según el grado de severidad clínica del asma (para PC20 VEF1 p < 0,001; PPC1 p < 0,001; PPC2 p < 0,001 e IgE sérica total p < 0,001). Existió una correlación significativa entre PPC1 y PPC2 y el grado de reactividad bronquial medida por el log (PC20 VEF1) (r=0,61, p < 0,001 y r=0,65, p < 0,001 respectivamente). Lo mismo surgió de correlacionar IgE sérica y log (PC20 VEF1) (r=0,78, p < 0,001). Conclusiones: Creemos que la sensibilización con aeroalergenos es un factor relevante en la génesis del asma de la infancia; este estudio mostró que los parámetros de atopia considerados se asociaron en forma cuantitativa con el grado de severidad clínica del asma y de reactividad bronquial a la metacolina