Silica-dust-exposed mine workers with scleroderma (systemic sclerosis).

The incidence of scleroderma (systemic sclerosis) was found to be increased in a population of black men who were gold miners. Ten men with scleroderma were detected during a five-year period. The annual incidence of the disease in this population in the group aged 33 to 57 years was estimated to be 81.8 per million. All of the men with scleroderma had disturbances of pulmonary function which were not present in a control group of silica-dust-exposed men without scleroderma. Not all of the subjects with scleroderma had silicosis, but all had been occupationally exposed to silica dust. There was a significant increase in the prevalence of tuberculosis in the past in the group with scleroderma, compared with a group of men with silicosis from the same population. The nature of the association of tuberculosis with scleroderma has not been defined.