Silicosis is a progressive, fibrotic, occupational lung disease resulting from inhalation of respirable crystalline silica. This disease is preventable through appropriate workplace practices. We systematically assessed an outbreak of silicosis among patients referred to our center for lung transplant.
This retrospective cohort analysis included all patients with a diagnosis of silicosis who were referred for evaluation to the National Lung Transplantation Program in Israel from January 1997 through December 2010. We also compared the incidence of lung transplantation (LTX) due to silicosis in Israel with that of the International Society for Heart and Lung Transplantation (ISHLT) registry.
During the 14-year study period, 25 patients with silicosis were referred for evaluation, including 10 patients who went on to undergo LTX. All patients were exposed by dry cutting a relatively new, artificial, decorative stone product with high crystalline silica content used primarily for kitchen countertops and bathroom fixtures. The patients had moderate-to-severe restrictive lung disease. Two patients developed progressive massive fibrosis; none manifested acute silicosis (silicoproteinosis). Three patients died during follow-up, without LTX. Based on the ISHLT registry incidence, 0.68 silicosis cases would have been expected instead of the 10 observed (incidence ratio, 14.6; 95% CI, 7.02-26.8).
This silicosis outbreak is important because of the worldwide use of this and similar high-silica-content, artificial stone products. Further cases are likely to occur unless effective preventive measures are undertaken and existing safety practices are enforced.From the Pulmonary Institute (Drs Kramer, Amital, and Rhahman), Rabin Medical Center, Beilinson Campus, Petach Tikva; the Pulmonary Department (Drs Guber and Shitrit), Meir Medical Center, Kfar Saba, affiliated with Sackler Faculty of Medicine, Tel Aviv University; the Institute of Pulmonary and Allergic Diseases (Dr Fireman), National Service for Interstitial Lung Diseases, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel; and the Division of Occupational and Environmental Medicine (Dr Blanc), Department of Medicine, University of California, San Francisco, San Francisco, CA.
Correspondence to: David Shitrit, MD, Pulmonary Department, Meir Medical Center, Kfar Saba 49100, Israel; e-mail: firstname.lastname@example.org
Author contributions: Dr Shitrit is the guarantor of the paper. He had full access to all of the study data and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Dr Kramer: contributed to the study design, data collection, and manuscript review and approval.
Dr Blanc: contributed to the data analysis and manuscript writing and approval.
Dr Fireman: contributed to the data collection and manuscript review and approval.
Dr Amital: contributed to the data collection and manuscript review and approval.
Dr Guber: contributed to the data collection and manuscript review and approval.
Dr Rhahman: contributed to the data collection and manuscript review and approval.
Dr Shitrit: contributed to the study design, data collection, statistical analysis, and manuscript writing.
Financial/nonfinancial disclosures: The authors have reported to CHEST that no potential conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.
Other contributions: The authors thank Faye Schreiber, MS, for editing the manuscript.Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details.Funding/Support: The authors have reported to CHEST that no funding was received for this study.