Silica-induced scleroderma

Scleroderma and occupational exposure

“…Our study tends to confirm a possible association between scleroderma and occupational exposure to silica dust among men. Taking into account the very low incidence of scleroderma among men, it is worth noting that both this study and the one by SluisCremes et a1 (7), as well as several other case reports (3)(4)(5)(6), are consistent with the hypothesis that silica exposure may represent an important risk factor in the etiopathogenesis of scleroderma. The fact that we were able to find an excess risk for silica exposure in this study is due to the relatively high prevalence of occupational categories engaged in rock drilling and in the stone industry in the study area.…”

“…Namely, the relation of scleroderma to occupational exposure is restricted to case reports (3,5,6,9,11,12). The only case-referent study was published by Sluis-Cremes et a1 (7) in 1985, who reported an association between progressive systemic sclerosis and the intensity of exposure to silica among white South African gold miners.…”

“…The etiology of scleroderma is still relatively unknown, although an association with occupational exposure to various chemicals and physical agents has been suggested in a number of case reports. Rather consistently, silica exposure has been reported in several cases of scleroderma in various countries, particularly among miners who, in many instances, have also been exposed to hand-arm vibration (3)(4)(5)(6). Exposure to silica has also been found to be associated with scleroderma in the only nested case-referent study which has been published on the subject (7).…”

Immunological Effects of Silica and Related Dysregulation of Autoimmunity

“…However, the roles and alterations of Th17 in silica-exposed patients are unknown and should be clarified through further research in order to obtain a better understanding of the immunological effects of silica on the human immune system. Many issues remain to be resolved, such as delineating the complications of SSc in SILs (Barnadas, 1986;Cowie, 1987Haustein, 1990Haustein & Anderegg, 1998;Sluis-Cremer, 1985), or those complications associated with malignant tumors such as mesothelioma and lung cancer in patients exposed to the mineral silicate asbestos (Greillier, 2008;Toyokuni, 2009;Miura, 2008). Regarding the relationship between tumor immunity and Treg function, it may be that Treg enhances cell numbers or function to reduce tumor immunity (Chattopadhyay, 2005;Danese & Rutella, 2007;Kretschmer, 2006).…”

“…Lung cancer is also considered to be associated with silicosis and the International Agency for Research on Cancer (IARC) categorized crystalline silica as a causative of lung cancer (Cocco, 2007;IARC, 1997;Pelucchi, 2006). In addition, it is well known that silicosis patients (SILs) often experience complications due to autoimmune diseases (Shanklin & Smalley, 1998;Steenland & Goldsmith, 1995;Uber & McReynolds, 1982) such as rheumatoid arthritis (known as Caplan syndrome) (Caplan, 1959(Caplan, , 1962, systemic lupus erythematosus (SLE) (Bartsch, 1980;Yamazaki 2007), systemic scleroderma (SSc) (Barnadas, 1986;Cowie, 1987Haustein, 1990Haustein & Anderegg, 1998;Sluis-Cremer, 1985) and antineutrophil cytoplasmic autoantibody (ANCA)-related vasculitis/nephritis (Bartůnková, 2006;Mulloy, 2003;Tervaert, 1998). Silica-induced dysregulation of autoimmunity has been thought to be caused by the adjuvant effect of silica (Cooper, 2008;Davis, 2001, Parks, 1999.…”