Occupational lung diseases, such as pneumoconiosis, are one of the health problems of dental workers that have been receiving increasing interest. Pulmonary amyloidosis is a heterogenous group of diseases and can be classified into primary (idiopathic) and secondary (associated with various inflammatory diseases, hereditary, or neoplastic). To date, the development of pulmonary amyloidosis in dental workers has not been reported. A 58-year-old Japanese female presented with chest discomfort and low-grade fever that has persisted for 2 months. She was a dental technician but did not regularly wear a dust mask in the workplace. Chest X ray and computed tomography revealed multiple well-defined nodules in both lungs and fluorodeoxyglucose (FDG)-positron emission tomography revealed abnormal FDG uptake in the same lesions with a maximal standardised uptake value (SUV [fusion_builder_container hundred_percent=”yes” overflow=”visible”][fusion_builder_row][fusion_builder_column type=”1_1″ background_position=”left top” background_color=”” border_size=”” border_color=”” border_style=”solid” spacing=”yes” background_image=”” background_repeat=”no-repeat” padding=”” margin_top=”0px” margin_bottom=”0px” class=”” id=”” animation_type=”” animation_speed=”0.3″ animation_direction=”left” hide_on_mobile=”no” center_content=”no” min_height=”none”][max]) of 5.6. We next performed thoracoscopic partial resection of the lesions in the right upper and middle lobes. The histological examination of the specimens revealed granuloma formation with foreign body-type giant cells and amyloid deposition that was confirmed by Congo red staining and direct fast scarlet (DFS) staining that produce apple-green birefringence under crossed polarised light. Because there were no other causes underlying the pulmonary amyloidosis, the authors performed electron probe X-ray microanalysis (EPMA) of the specimens and the result showed silica deposition in the lesions. Based on these results, the patient was finally diagnosed with pulmonary granulomas with amyloid deposition caused by chronic silica exposure. Afterward, her symptoms were improved and the disease has not progressed for 2 years since proper measures against additional occupational exposure were implemented. The authors found that this case presented three important clinical insights: First, occupational exposure to silica in a dental workplace could be associated with the development of amyloid deposition in lung. Second, EPMA was useful to reveal the aetiology of amyloid deposition in the lungs. Last, proper protection against silica is important to prevent further progression of the disease. In conclusion, the case suggested that occupational exposure to silica should be considered when amyloid deposition of unknown aetiology is found in the lungs of working or retired adults.
Authors: Hirano T, Numakura T, Moriyama H, Saito R, Shishikura Y, Shiihara J, Sugiura H, Ichinose M. ; Full Source: BMC Pulmonary Medicine. 2018 May 22;18(1):77. doi: 10.1186/s12890-018-0654-0.[/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]