Wheat dust-associated respiratory disease in a farming community.

Sixty-six volunteers who considered themselves to have wheat dust-related respiratory disease, were reviewed from a farming community. A spectrum of disease was described ranging from a mild allergic rhinitis limited to periods of wheat dust exposure through to perennial asthma in which wheat dust was but one of several precipitating factors. Approximately half of those with asthma had symptoms limited to times of wheat dust exposure. Results of a limited survey of farmers showed patterns of symptoms similar to those in the volunteer group. Most subjects were atopic with elevated IgE levels, and had positive skin prick tests to environmental allergens. All but one of 65 subjects tested had a positive RAST test to wheat dust antigen. It is concluded that wheat dust associated respiratory tract disease is a significant problem in Australian farming communities, that a particular pattern of asthma can be described, and that IgE mediated reactions contribute to this disease pattern.