[Two patients with summer-type hypersensitivity pneumonitis in Nagano Prefecture].

We encountered two patients with summer-type hypersensitivity pneumonitis that developed in Nagano Prefecture. Patient 1 was a 61-year-old man who had worked in warm and humid environments as painter. He was referred to our hospital because of fever, coughing and exertional dyspnea. Respiratory symptoms developed during work but were gone within in few weeks. Patient 2 was a 50-year-old housewife who was admitted to our hospital because of persistent coughing and a low-grade fever. In both patients, chest roentgenograms and computed tomograms showed bilateral, small, nodular and reticular shadows. Examination of a specimen obtained from patient 2 by transbronchial lung biopsy revealed alveolitis. In both patients, bronchoalveolar lavage fluid had low CD4/8 ratios, but in patient 1 the lymphocyte fraction was high and in patient 2 the neutrophil fraction was high. A steroid drug was given to patient 1 because of the patients symptoms and prolonged abnormal roentgenographic findings. Patient 2 reacted positively on a provocation test when returned to her house. Serum from both patients contained antibodies to Trichosporon mucoides and T. asahii. We know of no previous reports of summer-type hypersensitivity pneumonitis that developed in Nagano prefecture.