[Extrinsic allergic alveolitis of occupational origin: apropos of 2 cases]

Extrinsic Allergic Alveolitis (E.A.A.) is an immunological disorder caused by inhalation of various etiological agents (vegetable and animal dusts, fungi, organic simple chemicals) mostly present in work environment. Intensive and prolonged occupational exposure to antigens dimensionally able to reach peripheral airways, where they bring about their immunological effects, allows to consider hypersensitivity pneumonitis as a typical work-related disease. The wide range of pathological findings and evolution of E.A.A. often imply difficulty in diagnosis inspite of availability of diagnostic consolidated criteria. The integrated assessment of history and physical findings, radiological features, pulmonary functions tests, and specific and aspecific immunological data, often allows to make diagnostical conclusion without use of invasive methods (BAL and lung biopsy). In this note we refer two cases of E.A.A. occurred respectively in agricultural and industrial environment, whom etiological and evolutive features suggest an occupational pathogenesis. The first one is a typical "farmer's lung", the second one a hypersensitivity pneumonitis in a cheese washer. The diagnosis was performed by means of historical, clinical, radiological and pulmonary functional outcomes. In the first case specific serum precipitins against M. Faeni were present, in the second one the immunological pathogenesis of the pneumonitis was demonstrated by means of bronchial lavage cytological data and serum IgG dosage. In both cases the removal from specific antigen exposure and the prolonged steroid treatment induced symptomatological regression and complete recovery of functional tests.