Bronchial lability in children suffering from some diseases of the bronchi.

The authors studied bronchial reactivity in children with cystic fibrosis and with 
deformative bronchitis. The reaction of the bronchi was studied both by 
inhalatory and exercise provocation. Inhalatory tests were monitored by means of 
a whole body plethysmograph. Free- range run was used for the 
exercise test, and the peak expiratory flow rate was measured. The 
described technique of inhalatory tests was accurate, safe, and not tiring 
for the patient. No distinct difference in bronchial reaction between the 
two groups of patients could be stated. The bronchial reaction to 
the inhalatory and exercise tests was stronger in both groups than 
in normals but not as strong as in asthmatics. The nature 
of bronchial hyperreactivity in those patients is still unknown. The inhalatory 
test seems to be more sensitive than the exercise test in 
detecting that hyperreactivity. 