Correct
5. Pulmonary alveolar proteinosis
With the knowledge that the opacities on the chest radiograph are largely unchanged over a 4 month period, the differential diagnostic considerations for these opacities has shifted from a consideration of causes of acute, multifocal or diffuse pulmonary opacities to chronic multifocal or disuse pulmonary opacities. Among the considerations listed above, only pulmonary alveolar proteinosis would be expected to present as multifocal areas of ground-glass opacity and/or consolidation, with a background of linear and reticular opacities, remaining relatively unchanged over a 4 month period. A significant change or evolution in the appearance of the chest radiograph over a 4-month period would be expected for the other entities listed. Other diagnostic considerations for chronic, multifocal pulmonary opacities include several of the idiopathic interstitial pneumonias, chronic eosinophilic pneumonia, diffuse tumor infiltration, lipoid pneumonia, recurrent pulmonary hemorrhage, and recurrent aspiration.
The patient underwent thoracic CT (Figure 3) for further characterization of the abnormalities seen at chest radiography.
Figure 3. Panels A-F: selected static images of the thoracic CT scan. Lower panel: movie of the lung windows of the thoracic CT scan.
Which of the following statements regarding this CT examination is most accurate?