During the next 4 years, he had recurrent acute bronchospasm requiring emergency department visits and three hospitalizations. Physicians should be aware of this possibility when examining patients exposed to such materials. The syndrome is characterized by persistent airway hyperreactivity on nonspecific bronchial challenge testing.
Most cases occur after an accidental chemical spill or use of an improper work practice.
The mechanism by which persistent airway hyperreactivity is induced by irritant exposure is unknown. Persistent pulmonary inflammation may cause hyperresponsiveness1 by influencing bronchial smooth muscle and the response to histamine. Alteration of the irritant threshold of subepithelial irritant receptors in bronchial mucosa could also result in hyperresponsive airways. Another hypothesis involves the development of airway hyperresponsiveness from increased epithelial permeability due to bronchial epithelial damage. Approximately 5 minutes later, he had cough, eye and throat irritation, wheezing, and shortness of breath.