Sputum cytopathological findings in pig farmers

The purpose of this study is to compare the cytological changes in the resp iratory tracts of pig farmers exposed to an environment of swine confinemen t buildings with control, non-exposed subjects living in the same geographi cal area. Spontaneously produced sputum specimens were obtained from 133 pi g farmers and 120 control subjects, all clinically healthy, and grouped acc ording to smoking habits and sex. The findings of siderophages, eosinophils , abnormal columnar cells and respiratory spirals were significantly more f requent in the pig farmers. Siderophages were noted in 25.6% of pig farmers and in 5% of control subjects. By logistic regression analysis, pig farmin g is the single predictive factor for siderophages and eosinophils. For oth er cytological abnormalities, except Creola bodies and granular debris, smo king is the most significant predictive variable, but pig farming, age and male sex also con-elate with smoking. Atypical squamous metaplasia was obse rved in 11.3% of pig farmers and in 5.8% of control subjects. These finding s are in concordance with previous epidemiological and clinical studies and also reveal a new aspect of the harmful effect of pig farming exposure to the vascular and epithelial structures of the respiratory tract. It also de monstrates the usefulness of the simple method of sputum cytological analys is.