Table 2. Clinical Characteristics and Outcomes of Patients With Engineered Stone–Associated Silicosis.
| Clinical characteristic (No. with data available) | Overall (n = 52), No. (%) |
|---|---|
| Presenting symptoms (52) | |
| Asymptomatic | 7 (13) |
| Shortness of breath | 45 (87) |
| Cough | 38 (73) |
| Chest/back pain | 25 (48) |
| Weight loss | 18 (35) |
| Fevers | 10 (19) |
| Wheezing | 8 (15) |
| Pneumothorax | 5 (10) |
| Delayed diagnosis (52) | |
| Initial delay in diagnosis | 30 (58) |
| Time to correct diagnosis, median (IQR), mo | 3 (0-8) |
| Alternative initial diagnosis (30) | |
| Pulmonary tuberculosis | 8 (27) |
| Nontuberculous mycobacterial infection | 3 (10) |
| Sarcoidosis | 2 (7) |
| Asthma | 2 (7) |
| Bacterial pneumonia | 9 (30) |
| Other | 6 (20) |
| Tobacco use (52) | |
| Current or former smoker | 18 (36) |
| Pack-years among tobacco users, median (IQR) | 3.5 (1.25-6) |
| Comorbidities (52) | |
| Autoimmune disease | 6 (12) |
| Myositis | 1 (2) |
| Rheumatoid arthritis | 4 (8) |
| Systemic sclerosis or CREST syndrome | 1 (2) |
| Nontuberculous mycobacterial infection | 5 (10) |
| History of active pulmonary TB | 1 (2) |
| Other lung disease (COPD/asthma) | 2 (4) |
| Imaging (52) | |
| Predominant CT pattern | |
| Simple silicosis | 32 (62) |
| Progressive massive fibrosis | 20 (38) |
| Lung zone distribution | |
| Upper | 34 (65) |
| Lower | 5 (10) |
| Diffuse | 13 (25) |
| Lymphadenopathy (52) | |
| None | 6 (12) |
| Hilar only | 4 (8) |
| Mediastinal only | 12 (23) |
| Hilar and mediastinal | 30 (58) |
| Calcified lymphadenopathy (52) | 17 (33) |
| Ground glass opacities (51) | 19 (37) |
| Bronchiectasis (52) | 6 (12) |
| Cavitary lesions (51) | 5 (10) |
| Pleural effusion (52) | 6 (13) |
| Pleural thickening (52) | 4 (8) |
| Emphysema (52) | 2 (4) |
| Cardiomegaly (50) | 3 (6) |
| PFTs (44) | |
| PFT pattern (44) | |
| Normal | 13 (30) |
| Restriction | 24 (55) |
| Mixed | 6 (14) |
| Obstruction | 1 (2) |
| Severity of FEV1 reduction (44) | |
| Normal | 13 (20) |
| Mild | 9 (23) |
| Moderate | 8 (18) |
| Moderate-severe | 1 (2) |
| Severe | 8 (18) |
| Very severe | 5 (11) |
| Severity of DLCO reduction (43) | |
| Normal | 23 (54) |
| Mild | 5 (12) |
| Moderate | 11 (26) |
| Severe | 4 (9) |
| Air trapping (30) | 11 (37) |
| Lung biopsy (34) | |
| Bronchoscopic | |
| Transbronchial | 29 (85) |
| Lymph node | 16 (47) |
| Surgical (video assisted) | 5 (15) |
| Percutaneous needle | 2 (6) |
| Lung explant | 1 (3) |
| Pathologic features | |
| Characteristic findings of silicosis | 26 (76) |
| Birefringent crystals | 19 (58) |
| Granulomas | 14 (41) |
| Dust particles | 15 (46) |
| Fibrotic nodules | 12 (36) |
| Pulmonary alveolar proteinosis | 3 (9) |
| Outcomes (52) | |
| Deceased due to silicosis | 10 (19) |
| Time from diagnosis to death, median (IQR), mo (9) | 35 (19-52) |
| Age at death, median (IQR), years (9) | 46 (38-51) |
| Alive with hypoxia | 6 (12) |
| Alive without hypoxia | 35 (67) |
| Referred for lung transplant | 11 (21) |
| Formally declined | 7 (13) |
| Underwent transplant | 3 (6) |
Abbreviations: COPD, chronic obstructive pulmonary disease; CREST, calcinosis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia; CT, computed tomography; FEV1, forced expiratory volume in 1 second; DLCO, diffusion capacity of the lung for carbon monoxide; PFT, pulmonary function test; TB, tuberculosis.