Nonsensitizing causes of occupational asthma

Two forms of occupational asthma can be distinguished by whether they appear after a latency period (the usual type) or after single or multiple exposures-to an irritant material, called irritant-induced asthma or reactive airways dysfunction syndrome (resulting from a single exposure). In the last case, asthma-like symptoms occur within minutes or hours after exposure; Subjects may be left with permanent airway obstruction or hyperresponsiveness. Although there are several case reports of this condition, prospective epidemiologic, pathologic, and pathophysiologic data are scarce. The influence of treatment on the characteristics of the condition is still unknown.