[en] The purpose of the present report was to assess the high-resolution computed tomography (HRCT) findings in a group of patients diagnosed as having hypersensitivity penumonitis. HRCT was performed in 10 patients (6 women and 4 men) aged 19 to 56 years (mean: 36.5 years) who presented acute-subacute symptoms of hypersensitivity pneumonitis. Thin-section (1.5 mm) HRCT was carried out at the time of diagnosis all 10 patients, and 6 underwent follow-up HRCT studies. Plain chest X-ray was normal in the three cases. The most relevant HRCT findings were the presence of a nodular pattern (n=9) and ground-glass opacity (n=8). Focal areas of decreased density were observed in 4 cases. Mediastinal adenopathy was detected in 4 patients. The HRCT findings characteristic of hypersensitivity pneumonitis are centrilobular nodules and ground-glass opacity. (Author) 10 refs