Assessment of the lung tissue fibrosis in workers exposed to silica-hazardous dust for a long time

Abstract

Introduction. Silicosis is the most common and severe type of pneumoconiosis caused by inhalation of dust containing more than 10% of crystalline silica in the occupational setting. The chest X-ray plays a decisive role in the diagnosis of the disease.
 The purpose of our work was to establish lung tissue fibrosis in industrial workers suffering from silicosis.
 Materials and methods. In 2015–2022, ten patients with silicosis, employed at a Ural refractory manufacturing plant as press operators (Group 1) for the average of 17.23 ± 4.31 years, were examined at the Occupational Health Clinic of the Yekaterinburg Medical Research Center for Prophylaxis and Health Protection in Industrial Workers. The comparison group (Group 2) included 34 press operators without pneumoconiosis who had worked for more than 10 years in hazardous working conditions. The control group (Group 3) consisted of 32 people of different occupations unexposed to industrial dusts. All the subjects were matched by gender (male) and age (50.7 ± 5.25 years). Lung tissue fibrosis was measured by multislice computed tomography using a GE OPTIMA 660 128 Slice CT Scanner with accessories, GE HealthCare Japan, manufactured in 2012. The data were then analyzed in Statistica for Windows 7.
 Results. We established a decrease in tissue fibrosis in the apexes and inferior lobes of both lungs and an increase in the fibrosis in groups of target lymph nodes (11–14R, 2L, 10L) in the silicosis cases, and an increase in Hounsfield units in target groups of lymph nodes (2R, 4R, 10R, 11–14R, 2L, 11–14L) in the comparison group.
 Limitations. The study includes only workers engaged in refractory manufacturing with over 10 years of exposure to silica. For CT lung densitometry, the limitation is the permissible radiation dose of less than 5 mSv per year.
 Conclusion. The results of CT densitometry of the lungs and targeted groups of lymph nodes demonstrate its high efficiency in the quantitative assessment 
 of dust-related disorders in patients with silicosis and in experienced workers occupationally exposed to crystalline silica.