RESUMEN
The authors analyzed asbestos fibers in lung samples from 20 subjects with pleural plaques discovered on autopsy and compared the findings to their previous analyses of lungs from subjects with little or no asbestos exposure and no plaques. Sixteen of the subjects with plaques had a history of exposure to asbestos. The authors used electron-optical methods and energy-dispersive x-ray spectroscopy to investigate the structure, diffraction patterns, and chemical composition of the asbestos fibers. The subjects with plaques had significantly higher median concentrations than the control subjects for amosite and crocidolite fibers (P less than 0.01) but not for the other fiber types. Minimal microscopic asbestosis was present in the 3 subjects who had the highest amosite concentrations. In the subjects with typical plaques, a history of asbestos exposure, and more fibers than in the control population, the relation of the plaques to asbestos was confirmed; for others, it was uncertain.
Asunto(s)
Amianto/análisis , Pleura/análisis , Adulto , Anciano , Asbestosis/patología , Femenino , Humanos , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Pleura/ultraestructuraRESUMEN
We compared the numbers of asbestos bodies in 2 histologic sections of lung from 25 subjects showing a wide range of total asbestos burden with the numbers of asbestos bodies and fibers (analyzed by electron diffraction and x-ray spectroscopy) extracted from the lung. We also compared the numbers of extracted asbestos bodies with the numbers of fibers in 24 other subjects. Histologic and extracted asbestos bodies were correlated best with total asbestos fibers and with amosite and crocidolite fibers, and not at all with chrysotile fibers. Nevertheless, the total fiber count could not be reliably estimated from the count of either histologic or extracted bodies. Although asbestos bodies appeared to be fairly uniformly distributed in these lungs, detection of early fibrosis or asbestosis required careful examination of all portions of the parenchyma. When we defined asbestos histologically as clusters of 3 or more asbestos bodies adjacent to areas of fibrosis, we found that subjects with asbestosis had more than 240,000 asbestos fibers/g of wet lung. The nature of the disease in lungs showing fibrosis and more than 240,000 fibers/g, but only isolated asbestos bodies, is uncertain.