Response to bronchial provocation and exercise in children with cystic fibrosis.

Ten of fifteen cystic fibrosis children with positive skin prick tests to 
common antigens gave an immediate bronchial reaction to the antigen inhaled, 
five of them also gave a late reaction; however only one 
gave a history of asthma. The antigen most commonly eliciting a 
positive skin reaction in cystic fibrosis patients is Aspergillus fumigatus. In 
six children tested to this antigen the bronchial response varied, two 
were negative, one gave an immediate reaction and three gave a 
dual (immediate and late) reaction. None of the children showed the 
characteristic pattern of response to exercise seen in asthmatic patients, an 
initial rise in Peak Expiratory Flow Rate followed by a fall 
of greater than 14% below the resting level. Two patients showed 
an abnormal rise in Peak Expiratory Flow Rate during exercise, a 
pattern described previously in cystic fibrosis. The results suggest that bronchial 
allergy, immediate or late does completely explain susceptibility to asthma, and 
that other factors including perhaps the type of bronchial reactivity shown 
by bronchoconstriction after exercise may be required. However the majority of 
the children tested had bronchial allergy and anti- allergy therapy such 
as inhaled sodium cromoglycate may have a place in the management 
of selected patients with cystic fibrosis. 