Bronchial Challenge Testing in Asthma

Three of 7 positive challenges to Endo dust, which showed a negative skin reaction, may have been due to an irritant effect of the antigen rather than an allergic reaction. With the equipment at the time of the study, not only was the use of spirometry extremely labor intensive for patients and physicians, but also the methodology rapidly resulted in exhaustion for the children, and it was obvious that this would not enable the study to be completed with a significant number of patients.