Monitoring of peak expiratory flow rates in cork workers' occupational asthma

Suberosis is an occupational lung disorder of cork industry workers usually presenting as an extrinsic allergic alveolitis, but airway involvement in some cases makes the diagnostic approach complex. We assessed peak expirato ry flow rates (PEF) in 17 cork workers with asthma symptoms that worsened a t work, comparing three methods of PEF graph analysis. Complete agreement ( three observers) was found in 12 of 17 cases (70.6%) with the visual inspec tion of mean daily values and in II of 17 cases (64.7%) with the minimum, m aximum, and mean daily values (without any consensus in two cases). Accordi ng to the mean PEF graph, there were eight positive readings (47%), five ne gative readings (29%), and four dubious readings (24%); with the other grap hic analysis, two of the dubious cases were reclassified as negative. When we analyzed daily variability greater than or equal to 20%, we found only t hree positive results, one of which was in absolute disagreement with the v isual analysis. Our results suggest that it is possible to demonstrate occu pational asthma in cork work exposure. The visual inspection of PEF monitor ing shows a greater number of positive results than the index of daily vari ability; however, the latter may help to sort out dubious cases.