[Clinical study on asbestos pleurisy and review of literature]

Seven asbestos workers with asbestos pleurisy were investigated in terms of clinical symptoms, findings of pleural biopsies and course of chest roentgenograms. All cases were male and smokers. Duration of asbestos exposure ranged from 3 to 33 years (mean: 20.6 years). Duration between initial exposure and onset of the pleurisy ranged from 22 to 34 years (mean: 28.7 years). Five pleural effusions were aseptic and exudative, and one had sanguineus and eosinophilic effusion. According to the findings of pleural biopsies, our cases were classified into 2 groups. Group A (4 cases) had "basket-weaving formation" on the parietal side and inflammatory changes on the visceral side. No circulating autoantibodies were found in group A. Group B (3 cases) had no "basket-weaving formation" but only intensive inflammatory changes. These 3 cases were respectively complicated with anti-GBM antibody mediated glomerulonephritis, with acute interstitial pneumonia, and with rheumatoid arthritis and acute interstitial pneumonia. They all had circulating autoantibodies. In the course of chest roentgenograms, 6 of the 7 cases finally showed diffuse pleural thickenings which involved obliterations of costo-phrenic angles. Among them, one case developed into progressive pleural fibrosis. It was concluded that asbestos pleurisy can be classified into 2 groups according to the mechanism of occurrence, and immunological changes should be recognized as one of the mechanisms of asbestos pleurisy.