[Acute silicosis. Clinical, radiologic, functional, and cytologic characteristics of the broncho-alveolar fluids. Observations of 6 cases].

We describe six cases of acute silicosis which were characterised by an intense exposure to pure silica; there was a rapid onset with diffuse abnormalities on the radiological image and severe respiratory abnormalities. The duration of occupational exposure to silica was four to eighteen years. Three patients presented with a cough associated with disabling dyspnoea (stage III and IV). The physical examination showed finger clubbing in three patients and rales and crepitations on auscultation in two patients. There was general debility in four of the cases with weight loss. The chest x-ray showed a rapid progress with confluence of the diffuse nodular opacities. Respiratory function tests showed a restrictive ventilatory defect (mean +/- standard error of mean: TLC 67 +/- 5%, Vital Capacity +/- 7%, FEV1 63.5 +/- 6%) and alteration in the transfer factor for carbon monoxide (DLCO: 49.5 +/- 5%). The initial broncho-alveolar lavage showed a lymphocytosis (23.6 +/- 4.2%) associated with an alveolar neutrophilia (7 +/- 2.5%). A lung biopsy was carried out in three patients and a transbronchial biopsy in one patient confirming the diagnosis of silicosis in three cases and of silicoproteinosis in one case. After a period of eighteen months to 14 years, four patients died either due to cardiopulmonary complications of their disease (two cases) or to intercurrent disorders (two cases). The last two patients are currently stable.