A twenty-month-old boy with congenital cystic adenomatoid malformation is presented. He had a two-month history of unresolving pulmonary infiltration following a respiratory infection. Chest X-ray after bronchographic examination showed multiple lucent lesions occupying most of the right middle and lower lung fields, with contralateral shift of the mediastinum. At thoracotomy, multicystic lesion involving the right lower lobe was found. A lobectomy was performed and the histologic diagnosis was cystic adenomatoid malformation.
