[Exogenous fibrosing alveolitis due to the condensation aerosol (smoke) of zinc oxide].
Nyckelord
Abstrakt
Clinical-and-biological, biochemical, immunological, histomorphological; X-ray and functional examinations of workers of an electric-melting shop manufacturing brass alloys, who had contacts with condensation aerosol with a high zinc oxide concentrations, were used to detect in them pneumoconiosis with the exogenous fibrosing alveolitis (ZEFA). Some workers had acute conditions, i.e. "foundry fever" speaking in clinical terms, which was followed by a period of "visible improvement" lasting on the average for 8.6 +/- 0.8 years. The latter was described by the autoimmune activation of B-lymphocytes accompanied by an intensified formation of circulating immune complexes with a sharp reduction of the DR-cell content. The disease onset is gradual with the below signs: increasing dyspnea, cough and cyanosis of the lips due to the developing hypoxemia with decreasing PO2 (below 80 mm Hg); it can also be displayed through a mixed type of respiratory insufficiency with a lower PO2 and a higher PCO2 (above 40 mm Hg)-X-ray showed reticular changes in the pulmonary pattern. Generation of a high-above-norm quantity of active forms of oxygen and nitrogen by alveolar macrophages and neutrophils in their contacts with cellular membranes is the key mechanism triggering the pathological process like it happens in all cases of pneumoconiosis. Transformation of the mentioned products of free-radical oxygenation into hydroxyl radicals in the catalytic centers of the dust-particle borders containing zinc (which is, like iron, a metal with transient valence) is ZEFA specificity. The factor draws together ZEFA with pathological processes caused by asbestos-fiber dust, which have iron ions in their catalytic centers.