Demographics, occupational exposures and clinical features of cases
| Total (n=8 unless stated otherwise) | |
| Median age (range) | 34 years (27–56) |
| Country of birth | |
| UK | 2 (25%) |
| Outside UK | 6 (75%) |
| Smoking | |
| Current smoker | 4 (50%) |
| Ex-smoker | 3 (38%) |
| Never smoked | 1 (12%) |
| Median exposure history (range) | |
| All stone exposure | 12.5 years (4–40) |
| Artificial stone exposure | 6 years (4–10) |
| CT appearances | |
| Simple silicosis (nodules ≤10 mm diameter) | 4 (50%) |
| Complicated silicosis (nodules >10 mm diameter) | 3 (38%) |
| Acute silicoproteinosis | 1 (12%) |
| FEV1 range (% predicted) | 0.95 L (23%) to 3.62 L (99%) |
| FVC range (% predicted) | 1.40 L (28%) to 4.57 L (117%) |
| TLC range (% predicted) (n=7) | 25%–114% |
| DLCO range (% predicted) (n=6) | 41%–129% |
| Histology* (n=6) | |
| Non-caseating granulomata | 5/6 (83%) |
| Birefringent crystals under polarised light | 3/6 (50%) |
| Bloods | |
| Lymphopenia | 5/7 (71%) |
| Elevated serum ACE | 4/7 (57%) |
| Positive ANA† | 3/5 (60%) |
| NTM infection | 2 (25%) |
| Current situation | |
| Lost to follow-up | 1 (12%) |
| Deceased | 1 (12%) |
| Not working | 2 (25%) |
| Working unexposed to AS | 1 (25%) |
| Working exposed to AS | 3 (38%) |
*Endobronchial biopsy of mediastinal lymph node taken in six cases.
†Antinuclear antibodies (n=1: positive anti-ro and anti-la antibodies; n=1: positive ANA with coarse speckled pattern (titre 1:640) and positive anti U1RNP and anti RNP70 antibodies; n=1: positive ANA with fine speckled pattern (titre 1:160) with positive anti-ro 52 and anti-SS-A antibodies).
AS, artificial stone; DLCO, diffusing capacity of the lungs for carbon monoxide; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; NTM, non-tuberculosis mycobacterium; TLC, total lung capacity.