Sodium cromoglycate-induced changes in the dose-response curve of inhaled methacholine and histamine in asthmatic children.

The effect of inhalation of 2 per cent solution of sodium cromoglycate compared to that of saline on the bronchial response to methacholine and histamine was studied in 30 asthmatic children. Seven of 17 children challenged with methacholine showed decreased sensitivity after pretreatment with sodium cromoglycate. In 4 of 13 children, sodium cromoglycate attenuated the response to inhaled histamine.

The significance of bronchial and nasal provocation tests in making the diagnosis of allergy in children.

The relationship between positive skin tests and positive provocation tests at the affected organ level was studied in children with rhinitis and bronchial asthma. Of 357 positive skin reactions against pollens only 49% were positive in rhinometry, while of non pollen allergens only 31% of 59 challenges were positive. Of 778 challenges with pollens 40% gave a positive bronchial response, while only 27% of 848 challenges with non pollens were positive.

Bronchial hyperreactivity in cystic fibrosis and asthma.

We studied 113 patients with CF and compared their responsiveness to inhaled methacholine to that of 50 asthmatic children and 26 normal children. Positive responses to MCh occurred in 51% of the patients with CF and 98% of those with asthma. There was a significant correlation between a positive response to MCh in CF and poor pulmonary function.

Bronchial hyperreactivity to histamine and methacholine in asthmatic children after inhalation of SCH 1000 and chlorpheniramine maleate.

Nine asthmatic patients with a mean age of 14 yr received bronchial challenges with histamine and methacholine. The challenges were repeated after inhalation of 80 microgram of SCH 1000 (ipratropium bromide) and 5 mg of chlorpheniramine maleate. The provocation doses which produced a 20% fall in forced expiratory volume in 1 sec (FEV1) and the slopes of the dose-response curves were analyzed.