[Immunologic and respiratory findings in workers on a pig farm]

The prevalence of respiratory symptoms and ventilatory capacity in relation to immunological status were studied in 32 swine workers and in 39 controls. A large number of swine workers reacted to antigen of swine hair (34%) and to swine confinement antigen (28%) but also to other antigens such as animal food (78%), and corn flour (37%). Control workers showed comparable prevalence in their reaction to these antigens (17%, 25%, 51%, 25%). Increased IgE serum level was determined in three swine workers (9.4%) and in one control worker (2.6%). Swine workers with positive skin tests demonstrated significantly larger acute reductions in FEF50 and FEF25 than those with negative skin tests (P less than 0.01). The ventilatory capacity data measured before shift in swine workers with positive skin tests were significantly lower than the predicted normal values. Swine confinement antigen caused a dose-related contraction of guinea pig smooth muscle in vitro. Our data indicate that non-immunological reactions may be partly responsible for the acute and/or chronic changes in respiratory function.