Langerhans cell histiocytosis. Hand Schueller Christian: Chronic disseminated form, multifocal.

20 year old boy with diabetes insipidus, cough, fever, shortness of breath.

Conventional  CT reveals multiple small nodules thin-walled, irregular cysts predominantly in the upper 1/3 of the lungs.

Lytic defect of the parietal, frontal and maxillary bones in the skull.

Other lytic lesions in the femur (no image)

Etiology: Uncertain; Inflammatory ~ neoplastic

Epidemiology:  Affects 4 per 1 million                                                             

 Gender: M:F = 2:1