Persistent peripheral airway obstruction in children with severe asthma.

We reviewed pulmonary function data on 447 children with the diagnosis of asthma, who were studied in our laboratory over a 6-year interval. We found 19 with evidence of consistent airway obstruction. Two patients who had obvious causes for persistent obstruction were excluded. Seven of the remaining 17 patients consented to further studies. In six of the seven patients studied, flow rates at low lung volumes were severely depressed and remained unchanged after 2 weeks of vigorous "inpatient" therapy. No clinical benefit was apparent. One patient had relentlessly worse disease and died of his asthma. The autopsy revealed changes characteristic of asthma. We conclude that some children with severe asthma have persistent and severe peripheral airway obstruction. These findings challenge the current paradigm that asthma in children is a completely "reversible" illness. Long-term follow-up of children with persistent chronic obstruction may clarify the question of childhood origin of adult lung disease.