Feet at age 32 years. Digital cyanosis and sclerosis developed at approximately age 41 years.

Feet at age 32 years. Digital cyanosis and sclerosis developed at approximately age 41 years. The patient was diagnosed with systemic sclerosis at age 48 years. Case 2 is a 52-year-old man who worked in crystal processing for various jewelry-processing companies for 7 years, since the age of 23 years. He first showed signs of cyanosis in the third and fourth digits of both hands at age 32 years, was diagnosed with Raynaud’s syndrome at age 37 years, and was diagnosed with systemic sclerosis at age 38 years. Crystal processing is a detailed process that involves slabbing and trimming the selected amethyst and quartz crystals, which requires close proximity of the worker’s face with the target area. In the 1980s and 1990s, the working hours were 12 h per day, and the working environment involved 15 workers crowded into a small, 70-m2 space with poor ventilation. Conclusion: Two workers who processed crystals with a maximum crystalline silica content of 56.66 developed systemic sclerosis. Considering the epidemiological and DS5565 biological activity experimental evidence, exposure to crystalline silica dust was an important risk factor for systemic sclerosis. An active intervention is necessary to reduce exposure in similar exposure groups in the field of jewelry processing. Keywords: Crystalline silica, Jewelry, Systemic sclerosis, Occupational exposure, KoreaBackground Silica exists in crystalline and non-crystalline forms. The most common natural form of crystalline silica is quartz. Quartz is a colorless, odorless, non-combustible solid that widely exists in rocks, sand, and soil. Quartz causes silicosis via occupational respiratory exposure to the* Correspondence: [email protected] 1 Department of Occupational and Environmental Medicine, School of Medicine, Chosun University, 558 Pilmun-daero Dong-gu, Gwangju 61453, Republic of Korea Full list of author information is available at the end of the articlemineral dust form [1]. Miners, sandblasters, foundry workers, tunnel drillers, quarry workers, stone carvers, ceramic workers, and silica flour production workers are at a potential risk of exposure to crystalline silica [2]. When silicosis occurs simultaneously with scleroderma, it is called Erasmus syndrome. When silicosis and rheumatoid arthritis coexist, it is called Caplan’s syndrome. As such, research shows that exposure to crystalline silica is not limited to the lungs but is also related to systemic autoimmune disease [3]. A recent review on?The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/25962748 waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Kim et al. Annals of Occupational and Environmental Medicine (2017) 29:Page 2 ofenvironmental factors that affect autoimmune disease reported epidemiological evidence that exposure to crystalline silica contributes to the occurrence of diseases such as rheumatoid arthritis, systemic sclerosis, systemic lupus erythematosus, and antineutrophil cytoplasmic antibody-related vasculitis [4]. Systemic sclerosis is a connective t.