[Occupational interstitial lung diseases].

Pneumoconioses are induced by the inhalation of mineral or metallic dust. The incidence has decreased in the industrialized countries, but these diseases still exist. Diseases diagnosed nowadays may result from exposures that date back several decades. Besides, industry continuously creates new types of exposure and produces novel materials and alloys. Unusual exposures, sometimes in small workshops or in independent workers, may still cause severe diseases. In case of exposure to some metals, like beryllium, diseases may occur in susceptible subjects even at low levels of exposure. Medical and social consequences of misdiagnosis may be important. The diagnostic contribution of high resolution computed tomography (HRCT) scan is very important, as this technique is sensitive and specific. Pathological, mineralogical, and immunological techniques are useful in the differential diagnosis. Hypersensitivity pneumonitis is a granulomatous interstitial disease of the lungs due to immune reactions following chronic inhalation of antigens, to which the subject has been previously sensitised. Diagnosis is based on associated clinical and paraclinical signs which are not specific. Clinical approach is essential. It allows to suspect the diagnosis in view of respiratory symptoms, inspiratory crackles and the identification of a hazardous environment. Serological tests, bronchoalveolar lavage and HRCT scan are required to confirm diagnosis. Early removal of exposure prevents the occurrence of chronic respiratory failure. Corticosteroids can be used in severe forms during few weeks.