Silica exposure also is associated with an increased risk for TB. Silica and silicosis are risk factors for developing mycobacterial lung infections. According to Shukla and colleagues, patients with silicosis have a 10- to 30-fold increased incidence of TB. Fundamental research suggests that pulmonary macrophages damaged by silica may be unable to fight off the mycobacteria. Clinicians should closely investigate mycobacterial lung infections in workers with high silica exposures, to not miss the possible diagnosis of silicosis.
Silicosis is associated with an increased risk of developing autoimmune diseases and lung cancer.Specific autoantibodies have not been identified, but studies have demonstrated an association between silica exposure and systemic sclerosis, rheumatoid arthritis, antineutrophil cytoplasmic antibody-related vasculitis, and systemic lupus erythematosus. Silica dust is believed to promote or accelerate disease development, break immune tolerance, initiate autoimmunity, or magnify autoimmune vulnerability.
Respirable crystalline silica was recognized as early as 1997 by the International Agency for Research on Cancer as a human carcinogen, and its carcinogenicity was reconfirmed in a 2009 report.
Clinicians need to understand that silicosis can be more than a chronic disease that presents after many years of exposure to silica. Cases of acute and accelerated silicosis are increasing and need to be recognized as potential diagnoses in young workers with pulmonary complaints.
No cure exists for any form of silicosis, and lung transplantation is the only lifesaving treatment. Primary care clinicians must understand when patients are at risk for developing silicosis and not assume that a short time of exposure precludes the development of silicosis.