Combined silicosis and mixed dust pneumoconiosis with rapid progression: A case report and literature review

Figure 1 Serial chest radiographs and computed tomography scans of a 64-year-old man with rapidly progressing pneumoconiosis. A: Radiograph in November 2011 shows poorly-defined small nodules and fibrotic linear opacities in both upper lungs; B: Multiple poorly-defined small nodules were observed in both upper lobes, predominantly in posterior segments, on initial computed tomography (CT) scan obtained in November 2011. Minimal fibrotic linear opacities were also noted; C: Follow-up radiograph in February 2018 demonstrated significant increase in multiple small nodules in both lungs, with new poorly-defined large nodules in both upper lungs (arrows); D: Follow-up CT scan in February 2018 showed increased size and number of small poorly-defined nodules in both upper lobes, with ill-defined mass formation in posterior segments (arrows).

Figure 2 Histopathologic findings of lung biopsy specimen. A: Lung parenchyma was replaced by diffuse infiltration of phagocytic macrophages with focal areas of sclerosis (original magnification, ×100); B: Macrophages contained anthracotic pigment and rare multinucleated giant cells (original magnification, ×400); C: Polarized microscopic examination revealed many birefringent crystals (original magnification, ×400).