silicon and Bronchitis

To evaluate the possibility of quantifying alveolar dust burden in conditions of exposure to silica, four groups of subjects were submitted to bronchoalveolar lavage (BAL): 10 healthy control subjects and 39 patients affected by diffuse interstitial lung disease (DILD) never exposed to dust, 23 silicotic patients and 12 chronic bronchitis patients with a history of occupational exposure to silica dust. Five to ten million BAL recovered cells were analysed with an energy-dispersive X-ray microanalysis (EDXA) system to determine the silicon content, expressed in a semi-quantitative way as silicon to sulphur (Si/S) ratio. The results were independent of smoking habit. The Si/S median values (interquartile range in brackets) for the four groups were 0.53 (0.5-0.65), 0.60 (0.41-0.8), 1.23 (1.06-1.39), 1.31 (1.11-1.97), respectively. Silicotics and simply exposed individuals did not show a significant discrepancy, but they were both significantly different in comparison with normal and DILD patients without history of exposure (p less than 0.001). 14.3% false negative cases were found, and 4.1% false positive cases (none among normal subjects). We did not see any significant relationships between the amount of silicon and the duration of exposure or the degree of chest X-ray involvement. A study of cytocentrifuge slides from the same subjects by polarizing light microscopy revealed a lower sensitivity (34% false negative cases).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Bronchitis; Bronchoalveolar Lavage Fluid; Electron Probe Microanalysis; Female; Humans; Male; Microscopy, Polarization; Middle Aged; Occupational Exposure; Pulmonary Fibrosis; Silicon; Silicosis; Smoking; Time Factors

Topics: Anabolic Agents; Bronchitis; Chronic Disease; Drug Evaluation; Drug Therapy, Combination; Estrenes; Female; Humans; Male; Middle Aged; Molsidomine; Pulmonary Heart Disease; Silicon; Trimethylsilyl Compounds

Topics: Aged; Autopsy; Bronchitis; Coal Mining; Collagen; Dust; Dyspnea; Humans; Lung; Male; Organ Size; Pneumoconiosis; Pulmonary Emphysema; Pulmonary Heart Disease; Radiography; Silicon