Cryptogenic organizing pneumonia

Bilateral ill-defined nodular opacities throughout both lungs with more confluent consolidation in the left upper lobe. Several of the nodules have apparent central lucency which is suspicious for cavitation. The lung volumes are reduced. There is no pleural fluid and the cardiac and mediastinal contours are normal.

COP may explain the reduced lung volumes and more peripheral confluent areas of consolidation, particularly in the left upper lobe. The possibility of cavitating nodules is however not easily explained and in the immunocompromised patient consideration to invasive aspergillosis or other atypical infections should be given.

Multifocal areas of nodular consolidation and ground glass opacity in a predominantly peribronchial and subpleural distribution, slightly worse in the upper lobes demonstrated. No cavitation, intrapulmonary mass or significant collapse seen. 

Tiny bibasal pleural effusions. A few small pretracheal nodes, however no evidence of hilar, mediastinal, supraclavicular or axillary lymphadenopathy.

Heart and pericardium are within normal limits. No pericardial effusion. Visualized upper abdominal organs are unremarkable. 

Conclusion: Multifocal nodular consolidation and ground glass opacity subpleural and peribronchial in distribution are very suggestive of COP. It would be important to correlate with time post-BMT. Other differentials, such as atypical fungal infection such as aspergillosis, are thought less likely.