[Farmer's lung. Report of a case (author's transl)].

Asthenia, anorexia, fever, weight loss, dyspnea and cough developed insidiously over 3 months in a patient working in a farm and exposed to moldy organic dusts (hay and alfalfa). Complete recovery occurred when exposure was stopped, but symptoms reappeared when the patient took the same job again. Pulmonary function tests showed reduced compliance and diffusion of gases. The demonstration of precipitating antibodies to moldy hay extracts confirmed the diagnosis of farmer's lung. Eight months after discontinuance of exposure and on steroid therapy the patient was asymptomatic with spirometric values within normal limits. Chest roentgenogram showed a residual finely reticular pattern in the superior lobules. The importance of an early diagnosis and subsequent change of job in order to avoid irreversible pulmonary fibrosis is stressed.