[Male-type scleroderma: the role of occupational exposure]

A number of occupational exposure risks have been suspected as potential causes of scleroderma (systemic sclerosis), particularly in males. These include silica dust and numerous organic chemicals. With particular reference to the type of employment, we have reviewed the charts of male scleroderma patients receiving treatment in our Rheumatology Department since 1976. Of 39 patients, 25 could be included in the present study. Among these, 14 (56%) had an occupational activity which put them at risk: 11 were exposed to silica dust, one to organic chemicals and two to both silica dust and chemicals. Mean exposure time was 14.5 years (range 4-33 years); and the interval between the beginning of exposure and the onset of scleroderma averaged 24.4 years (range 4-45 years). Considering these 14 cases as silica- or chemically-induced scleroderma, we found that, except for the absence of muscular involvement, the clinical features and prognosis were similar to those of "idiopathic" scleroderma patients. Antinuclear antibodies and autoantibodies directed against Scl-70 were also found in both occupationally induced and idiopathic scleroderma. Our results emphasize the unusually high frequency of occupational exposure in scleroderma in males. Hence, a detailed professional history should be taken for all scleroderma patients. Our results also suggest that, in certain cases, scleroderma should be classified as an occupational disease.