Pulmonary Langerhans cell histiocytosis: the many faces of presentation at initial CT scan

Insights into Imaging

Table 1 Lesion presentation patterns: diseases to differentiate from PLCH

Nodules/micronodules	Cavitating nodules	Cysts
Lung metastasis Tuberculosis/infectious nodules Sarcoidosis, silicosis Wegener disease/vasculitis nodules ^aRB-ILD	Wegener disease/vasculitis nodules Lung metastasis Septic emboli Cavitated P. jiroveci lesions	Lymphangioleiomyomatosis Centrilobular emphysema UIP Lung metastasis LIP^a,b, HP^a,b, DIP^a,b Cystic fibrohistiocytic tumour Birt Hogg Dubé syndrome Light-chain disease Amyloidosis Pneumatocoeles

^aRB-ILD respiratory bronchiolitis interstitial lung disease, DIP desquamative interstitial pneumonia, LIP lymphocytic interstitial pneumonia, HP hypersensitivity pneumonitis
^bUsually in association with ground-glass opacities and pulmonary changes that may suggest the disease