Histiocystosis X,”Abnormal proliferation of histiocytes, usually in smokersLocalized in lung or bone = eosinophilic granulomaTwo systemic forms = Letterer-Siwe disease, Hand-Schuller-Christian syndrome CXR has honeycomb appearance

Histiocystosis X,”Abnormal proliferation of histiocytes, usually in smokersLocalized in lung or bone = eosinophilic granulomaTwo systemic forms = Letterer-Siwe disease, Hand-Schuller-Christian syndrome CXR has honeycomb appearance

cysts on CT”