RESUMO
Between 1976-1986 fifty-seven patients with farmer's lung have been diagnosed in Hungary on the basis of data obtained from public institutes for tuberculosis. That are 0.08% of the 744,300 manual workers employed in agriculture and forestry. In the counties of Borsod and Szolnok the rate was 0.5% (referred to 62,900 and 36,000 individuals, respectively). Regional accumulation of the different provoking agent's and variation of disease prevalence seem to be in correlation with geographical, climatic, meteorological, economical and occupational factors, showing a declining tendency in recent years. Antibodies of the Thermoactinomyces vulgaris antigen could be detected most frequently. In the biopsy material of 17 patients obtained by Klassen biopsy were fibrosing and not fibrosing desquamative alveolitis, granulomas similar to sarcoidosis, bronchiolitis with peribronchial fibrosis observed. Mostly focal, rarely subpleural deficiencies were detected by lung-scintigraphy, their dimension in acute cases being greater than the extent of radiological lesions. On the basis of 5 Coombs positive cases authors consider conceivable that sometimes cytotoxic allergic reaction type II participates in the pathogenesis of farmer's lung.