Computed tomographic appearance of pulmonary alveolar proteinosis in adults

Two cases of adult pulmonary alveolar proteinosis are presented with emphasis on the computed tomographic findings in both cases. Each patient demonstrated a pattern of diffusely increased lung density on both standard radiographic and computed tomographic examinations of the lung. There was no evidence of adenopathy, pleural effusion, or cardiomegaly in either patient. The diagnosis of pulmonary alveolar proteinosis was established in both patients by open lung biopsy. The optical microscopy and electron microscopy examinations of the biopsy material in each instance demonstrated marked filling of the alveoli with periodic-acid-Schiff-positive material and intraalveolar lamellar bodies. The diagnosis of sarcoid was entertained prior to the open lung biopsy in one patient, a young adult black male. Although the computed tomographic appearance was similar in each case and of no value in the diagnosis of pulmonary alveolar proteinosis, it was helpful in assessing the extent of the disease within the lung.