A series of nine infants, 2-8 months of age, with a history of animal or vegetable fat intake within 10 days after birth, is presented. The infants developed respiratory problems and failure to thrive. Plain films and computed tomography showed areas of consolidation in the medial-posterior parts of the lungs. The areas of consolidation showed three types of changes at computed tomography. Attenuation measurements did not reveal fat. To establish the diagnosis, fine needle aspiration biopsy, tru-cut biopsy and/or open lung biopsy was done in eight infants and bronchopulmonary lavage in one patient. The pathological findings were an intense lymphocytic infiltration with scattered granulomas which contained lipid deposit.