40 years old man complain from shortness of breath::
Correct Answer: Eosinophilic granuloma
Eosinophilic granuloma, also known as pulmonary histiocytosis X (PHX) or pulmonary Langerhans cell histiocytosis X (PLCH), is an uncommon interstitial lung disease that is epidemiologically related to tobacco smoking. It chiefly affects young adults, primarily occurring in the third or fourth decades of life.
Radiographic Features:
Nodular (1-15 mm) or reticulonodular pattern on chest radiograph with a middle and upper lung predominance
Subsequent necrosis and cavitation of the nodules is best visualized with CT, and later becomes the dominant finding
Irregular cystic airspaces (typically 1- 2 cm, up to 5 cm)
The resultant increase in lung volumes with disease progression
Adenopathy and pleural effusions are rare
Spontaneous pneumothoraces (6-25%)
Differential Diagnosis:
Differential depends on whether the nodular or cystic change is the dominant feature.
Early in the disease, when nodules are the dominant feature, consider:
granulomatous disease
granulomatosis with polyangiitis
sarcoidosis
metastases
miliary tuberculosis
Later in the disease, when cysts are prominent, consider:
